Heart Failure

It remained an open question in 2018, on the unveiling of the COAPT trial’s 2-year primary results, whether the striking reductions in mortality and heart-failure (HF) hospitalization observed for transcatheter edge-to-edge repair (TEER) with the MitraClip (Abbott) would be durable with longer follow-up.

The trial had enrolled an especially sick population of symptomatic patients with mitral regurgitation (MR) secondary to HF.

As it turns out, the therapy’s benefits at 2 years were indeed durable, at least out to 5 years, investigators reported March 5 at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. The results were simultaneously published in the New England Journal of Medicine.

Patients who received the MitraClip on top of intensive medical therapy, compared with a group assigned to medical management alone, benefited significantly at 5 years with risk reductions of 51% for HF hospitalization, 28% for death from any cause, and 47% for the composite of the two events.

Still, mortality at 5 years among the 614 randomized patients was steep at 57.3% in the MitraClip group and 67.2% for those assigned to meds only, underscoring the need for early identification of patients appropriate for the device therapy, Gregg W. Stone, MD, said during his presentation.

Dr. Stone, of the Icahn School of Medicine at Mount Sinai, New York, is a COAPT co-principal investigator and lead author of the 5-year outcomes publication.

Exclusions based on LV dimension

The COAPT trial included 614 patients with HF and symptomatic MR despite guideline-directed medical therapy. They were required to have moderate to severe (3+) or severe (4+) MR confirmed by an echocardiographic core laboratory and a left ventricular ejection fraction (LVEF) of 20%-50%.

Among the exclusion criteria were an LV end-systolic diameter greater than 70 mm, severe pulmonary hypertension, and moderate to severe symptomatic right ventricular failure.

The systolic LV dimension exclusion helped address the persistent question of whether “severe mitral regurgitation is a marker of a bad left ventricle or ... contributes to the pathophysiology” of MR and its poor outcomes, Dr. Stone said.

The 51% reduction in risk for time-to-first HF hospitalization among patients assigned to TEER “accrued very early,” Dr. Stone pointed out. “You can see the curves start to separate almost immediately after you reduce left atrial pressure and volume overload with the MitraClip.”

The curves stopped diverging after about 3 years because of crossover from the control group, he said. Still, “we had shown a substantial absolute 17% reduction in mortality at 2 years” with MitraClip. “That has continued out to 5 years, with a statistically significant 28% relative reduction,” he continued, and the absolute risk reduction reaching 10%.

Patients in the control group who crossed over “basically assumed the death and heart failure hospitalization rate of the MitraClip group,” Dr. Stone said. That wasn’t surprising “because most of the patients enrolled in the trial originally had chronic heart failure.” It’s “confirmation of the principal results of the trial.”
 

Comparison With MITRA-FR

“We know that MITRA-FR was a negative trial,” observed Wayne B. Batchelor, MD, an invited discussant following Dr. Stone’s presentation, referring to an earlier similar trial that showed no advantage for MitraClip. Compared with MITRA-FR, COAPT “has created an entirely different story.”

The marked reductions in mortality and risk for adverse events and low number-needed-to-treat with MitraClip are “really remarkable,” said Dr. Batchelor, who is with the Inova Heart and Vascular Institute, Falls Church, Va.

But the high absolute mortality for patients in the COAPT control group “speaks volumes to me and tells us that we’ve got to identify our patients well early,” he agreed, and to “implement transcatheter edge-to-edge therapy in properly selected patients on guideline-directed medical therapy in order to avoid that.”

The trial findings “suggest that we’re reducing HF hospitalization,” he said, “so this is an extremely potent therapy, potentially.

“The dramatic difference between the treated arm and the medical therapy arm in this trial makes me feel that this therapy is here to stay,” Dr. Batchelor concluded. “We just have to figure out how to deploy it properly in the right patients.”

The COAPT trial presents “a practice-changing paradigm,” said Suzanne J. Baron, MD, of Lahey Hospital & Medical Center, Burlington, Mass., another invited discussant.

The crossover data “really jumped out,” she added. “Waiting to treat patients with TEER may be harmful, so if we’re going to consider treating earlier, how do we identify the right patient?” Dr. Baron asked, especially given the negative MITRA-FR results.

MITRA-FR didn’t follow patients beyond 2 years, Dr. Stone noted. Still, “we do think that the main difference was that COAPT enrolled a patient population with more severe MR and slightly less LV dysfunction, at least in terms of the LV not being as dilated, so they didn’t have end-stage LV disease. Whereas in MITRA-FR, more of the patients had only moderate mitral regurgitation.” And big dilated left ventricles “are less likely to benefit.”

There were also differences between the studies in technique and background medical therapies, he added.

The Food and Drug Administration has approved – and payers are paying – for the treatment of patients who meet the COAPT criteria, “in whom we can be very confident they have a benefit,” Dr. Stone said.

“The real question is: Where are the edges where we should consider this? LVEF slightly less than 20% or slightly greater than 50%? Or primary atrial functional mitral regurgitation? There are registry data to suggest that they would benefit,” he said, but “we need more data.”

COAPT was supported by Abbott. Dr. Stone disclosed receiving speaker honoraria from Abbott and consulting fees or equity from Neovasc, Ancora, Valfix, and Cardiac Success; and that Mount Sinai receives research funding from Abbott. Disclosures for the other authors are available at nejm.org. Dr. Batchelor has disclosed receiving consultant fees or honoraria from Abbott, Boston Scientific, Idorsia, and V-Wave Medical, and having other ties with Medtronic. Dr. Baron has disclosed receiving consultant fees or honoraria from Abiomed, Biotronik, Boston Scientific, Edwards Lifesciences, Medtronic, Shockwave, and Zoll Medical, and conducting research or receiving research grants from Abiomed and Boston Scientific.
 

A version of this article originally appeared on Medscape.com.

It remained an open question in 2018, on the unveiling of the COAPT trial’s 2-year primary results, whether the striking reductions in mortality and heart-failure (HF) hospitalization observed for transcatheter edge-to-edge repair (TEER) with the MitraClip (Abbott) would be durable with longer follow-up.

The trial had enrolled an especially sick population of symptomatic patients with mitral regurgitation (MR) secondary to HF.

As it turns out, the therapy’s benefits at 2 years were indeed durable, at least out to 5 years, investigators reported March 5 at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. The results were simultaneously published in the New England Journal of Medicine.

Patients who received the MitraClip on top of intensive medical therapy, compared with a group assigned to medical management alone, benefited significantly at 5 years with risk reductions of 51% for HF hospitalization, 28% for death from any cause, and 47% for the composite of the two events.

Still, mortality at 5 years among the 614 randomized patients was steep at 57.3% in the MitraClip group and 67.2% for those assigned to meds only, underscoring the need for early identification of patients appropriate for the device therapy, Gregg W. Stone, MD, said during his presentation.

Dr. Stone, of the Icahn School of Medicine at Mount Sinai, New York, is a COAPT co-principal investigator and lead author of the 5-year outcomes publication.

Exclusions based on LV dimension

The COAPT trial included 614 patients with HF and symptomatic MR despite guideline-directed medical therapy. They were required to have moderate to severe (3+) or severe (4+) MR confirmed by an echocardiographic core laboratory and a left ventricular ejection fraction (LVEF) of 20%-50%.

Among the exclusion criteria were an LV end-systolic diameter greater than 70 mm, severe pulmonary hypertension, and moderate to severe symptomatic right ventricular failure.

The systolic LV dimension exclusion helped address the persistent question of whether “severe mitral regurgitation is a marker of a bad left ventricle or ... contributes to the pathophysiology” of MR and its poor outcomes, Dr. Stone said.

The 51% reduction in risk for time-to-first HF hospitalization among patients assigned to TEER “accrued very early,” Dr. Stone pointed out. “You can see the curves start to separate almost immediately after you reduce left atrial pressure and volume overload with the MitraClip.”

The curves stopped diverging after about 3 years because of crossover from the control group, he said. Still, “we had shown a substantial absolute 17% reduction in mortality at 2 years” with MitraClip. “That has continued out to 5 years, with a statistically significant 28% relative reduction,” he continued, and the absolute risk reduction reaching 10%.

Patients in the control group who crossed over “basically assumed the death and heart failure hospitalization rate of the MitraClip group,” Dr. Stone said. That wasn’t surprising “because most of the patients enrolled in the trial originally had chronic heart failure.” It’s “confirmation of the principal results of the trial.”
 

Comparison With MITRA-FR

“We know that MITRA-FR was a negative trial,” observed Wayne B. Batchelor, MD, an invited discussant following Dr. Stone’s presentation, referring to an earlier similar trial that showed no advantage for MitraClip. Compared with MITRA-FR, COAPT “has created an entirely different story.”

The marked reductions in mortality and risk for adverse events and low number-needed-to-treat with MitraClip are “really remarkable,” said Dr. Batchelor, who is with the Inova Heart and Vascular Institute, Falls Church, Va.

But the high absolute mortality for patients in the COAPT control group “speaks volumes to me and tells us that we’ve got to identify our patients well early,” he agreed, and to “implement transcatheter edge-to-edge therapy in properly selected patients on guideline-directed medical therapy in order to avoid that.”

The trial findings “suggest that we’re reducing HF hospitalization,” he said, “so this is an extremely potent therapy, potentially.

“The dramatic difference between the treated arm and the medical therapy arm in this trial makes me feel that this therapy is here to stay,” Dr. Batchelor concluded. “We just have to figure out how to deploy it properly in the right patients.”

The COAPT trial presents “a practice-changing paradigm,” said Suzanne J. Baron, MD, of Lahey Hospital & Medical Center, Burlington, Mass., another invited discussant.

The crossover data “really jumped out,” she added. “Waiting to treat patients with TEER may be harmful, so if we’re going to consider treating earlier, how do we identify the right patient?” Dr. Baron asked, especially given the negative MITRA-FR results.

MITRA-FR didn’t follow patients beyond 2 years, Dr. Stone noted. Still, “we do think that the main difference was that COAPT enrolled a patient population with more severe MR and slightly less LV dysfunction, at least in terms of the LV not being as dilated, so they didn’t have end-stage LV disease. Whereas in MITRA-FR, more of the patients had only moderate mitral regurgitation.” And big dilated left ventricles “are less likely to benefit.”

There were also differences between the studies in technique and background medical therapies, he added.

The Food and Drug Administration has approved – and payers are paying – for the treatment of patients who meet the COAPT criteria, “in whom we can be very confident they have a benefit,” Dr. Stone said.

“The real question is: Where are the edges where we should consider this? LVEF slightly less than 20% or slightly greater than 50%? Or primary atrial functional mitral regurgitation? There are registry data to suggest that they would benefit,” he said, but “we need more data.”

COAPT was supported by Abbott. Dr. Stone disclosed receiving speaker honoraria from Abbott and consulting fees or equity from Neovasc, Ancora, Valfix, and Cardiac Success; and that Mount Sinai receives research funding from Abbott. Disclosures for the other authors are available at nejm.org. Dr. Batchelor has disclosed receiving consultant fees or honoraria from Abbott, Boston Scientific, Idorsia, and V-Wave Medical, and having other ties with Medtronic. Dr. Baron has disclosed receiving consultant fees or honoraria from Abiomed, Biotronik, Boston Scientific, Edwards Lifesciences, Medtronic, Shockwave, and Zoll Medical, and conducting research or receiving research grants from Abiomed and Boston Scientific.
 

A version of this article originally appeared on Medscape.com.

It remained an open question in 2018, on the unveiling of the COAPT trial’s 2-year primary results, whether the striking reductions in mortality and heart-failure (HF) hospitalization observed for transcatheter edge-to-edge repair (TEER) with the MitraClip (Abbott) would be durable with longer follow-up.

The trial had enrolled an especially sick population of symptomatic patients with mitral regurgitation (MR) secondary to HF.

As it turns out, the therapy’s benefits at 2 years were indeed durable, at least out to 5 years, investigators reported March 5 at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. The results were simultaneously published in the New England Journal of Medicine.

Patients who received the MitraClip on top of intensive medical therapy, compared with a group assigned to medical management alone, benefited significantly at 5 years with risk reductions of 51% for HF hospitalization, 28% for death from any cause, and 47% for the composite of the two events.

Still, mortality at 5 years among the 614 randomized patients was steep at 57.3% in the MitraClip group and 67.2% for those assigned to meds only, underscoring the need for early identification of patients appropriate for the device therapy, Gregg W. Stone, MD, said during his presentation.

Dr. Stone, of the Icahn School of Medicine at Mount Sinai, New York, is a COAPT co-principal investigator and lead author of the 5-year outcomes publication.

Exclusions based on LV dimension

The COAPT trial included 614 patients with HF and symptomatic MR despite guideline-directed medical therapy. They were required to have moderate to severe (3+) or severe (4+) MR confirmed by an echocardiographic core laboratory and a left ventricular ejection fraction (LVEF) of 20%-50%.

Among the exclusion criteria were an LV end-systolic diameter greater than 70 mm, severe pulmonary hypertension, and moderate to severe symptomatic right ventricular failure.

The systolic LV dimension exclusion helped address the persistent question of whether “severe mitral regurgitation is a marker of a bad left ventricle or ... contributes to the pathophysiology” of MR and its poor outcomes, Dr. Stone said.

The 51% reduction in risk for time-to-first HF hospitalization among patients assigned to TEER “accrued very early,” Dr. Stone pointed out. “You can see the curves start to separate almost immediately after you reduce left atrial pressure and volume overload with the MitraClip.”

The curves stopped diverging after about 3 years because of crossover from the control group, he said. Still, “we had shown a substantial absolute 17% reduction in mortality at 2 years” with MitraClip. “That has continued out to 5 years, with a statistically significant 28% relative reduction,” he continued, and the absolute risk reduction reaching 10%.

Patients in the control group who crossed over “basically assumed the death and heart failure hospitalization rate of the MitraClip group,” Dr. Stone said. That wasn’t surprising “because most of the patients enrolled in the trial originally had chronic heart failure.” It’s “confirmation of the principal results of the trial.”
 

Comparison With MITRA-FR

“We know that MITRA-FR was a negative trial,” observed Wayne B. Batchelor, MD, an invited discussant following Dr. Stone’s presentation, referring to an earlier similar trial that showed no advantage for MitraClip. Compared with MITRA-FR, COAPT “has created an entirely different story.”

The marked reductions in mortality and risk for adverse events and low number-needed-to-treat with MitraClip are “really remarkable,” said Dr. Batchelor, who is with the Inova Heart and Vascular Institute, Falls Church, Va.

But the high absolute mortality for patients in the COAPT control group “speaks volumes to me and tells us that we’ve got to identify our patients well early,” he agreed, and to “implement transcatheter edge-to-edge therapy in properly selected patients on guideline-directed medical therapy in order to avoid that.”

The trial findings “suggest that we’re reducing HF hospitalization,” he said, “so this is an extremely potent therapy, potentially.

“The dramatic difference between the treated arm and the medical therapy arm in this trial makes me feel that this therapy is here to stay,” Dr. Batchelor concluded. “We just have to figure out how to deploy it properly in the right patients.”

The COAPT trial presents “a practice-changing paradigm,” said Suzanne J. Baron, MD, of Lahey Hospital & Medical Center, Burlington, Mass., another invited discussant.

The crossover data “really jumped out,” she added. “Waiting to treat patients with TEER may be harmful, so if we’re going to consider treating earlier, how do we identify the right patient?” Dr. Baron asked, especially given the negative MITRA-FR results.

MITRA-FR didn’t follow patients beyond 2 years, Dr. Stone noted. Still, “we do think that the main difference was that COAPT enrolled a patient population with more severe MR and slightly less LV dysfunction, at least in terms of the LV not being as dilated, so they didn’t have end-stage LV disease. Whereas in MITRA-FR, more of the patients had only moderate mitral regurgitation.” And big dilated left ventricles “are less likely to benefit.”

There were also differences between the studies in technique and background medical therapies, he added.

The Food and Drug Administration has approved – and payers are paying – for the treatment of patients who meet the COAPT criteria, “in whom we can be very confident they have a benefit,” Dr. Stone said.

“The real question is: Where are the edges where we should consider this? LVEF slightly less than 20% or slightly greater than 50%? Or primary atrial functional mitral regurgitation? There are registry data to suggest that they would benefit,” he said, but “we need more data.”

COAPT was supported by Abbott. Dr. Stone disclosed receiving speaker honoraria from Abbott and consulting fees or equity from Neovasc, Ancora, Valfix, and Cardiac Success; and that Mount Sinai receives research funding from Abbott. Disclosures for the other authors are available at nejm.org. Dr. Batchelor has disclosed receiving consultant fees or honoraria from Abbott, Boston Scientific, Idorsia, and V-Wave Medical, and having other ties with Medtronic. Dr. Baron has disclosed receiving consultant fees or honoraria from Abiomed, Biotronik, Boston Scientific, Edwards Lifesciences, Medtronic, Shockwave, and Zoll Medical, and conducting research or receiving research grants from Abiomed and Boston Scientific.
 

A version of this article originally appeared on Medscape.com.

The relatively recent innovation of heart transplantation after circulatory death of the donor is increasing the number of donor hearts available and leading to many more lives on the heart transplant waiting list being saved. Experts agree it’s a major and very welcome advance in medicine.

However, some of the processes involved in one approach to donation after circulatory death has raised ethical concerns and questions about whether they violate the “dead donor rule” – a principle that requires patients be declared dead before removal of life-sustaining organs for transplant.  

Rasi Bhadramani/iStock/Getty Images

Experts in the fields of transplantation and medical ethics have yet to reach consensus, causing problems for the transplant community, who worry that this could cause a loss of confidence in the entire transplant process.
 

A new pathway for heart transplantation

The traditional approach to transplantation is to retrieve organs from a donor who has been declared brain dead, known as “donation after brain death (DBD).” These patients have usually suffered a catastrophic brain injury but survived to get to intensive care.

As the brain swells because of injury, it becomes evident that all brain function is lost, and the patient is declared brain dead. However, breathing is maintained by the ventilator and the heart is still beating. Because the organs are being oxygenated, there is no immediate rush to retrieve the organs and the heart can be evaluated for its suitability for transplant in a calm and methodical way before it is removed.  

However, there is a massive shortage of organs, especially hearts, partially because of the limited number of donors who are declared brain dead in that setting.

In recent years, another pathway for organ transplantation has become available: “donation after circulatory death (DCD).” These patients also have suffered a catastrophic brain injury considered to be nonsurvivable, but unlike the DBD situation, the brain still has some function, so the patient does not meet the criteria for brain death. 

Still, because the patient is considered to have no chance of a meaningful recovery, the family often recognizes the futility of treatment and agrees to the withdrawal of life support. When this happens, the heart normally stops beating after a period of time. There is then a “stand-off time” – normally 5 minutes – after which death is declared and the organs can be removed. 

The difficulty with this approach, however, is that because the heart has been stopped, it has been deprived of oxygen, potentially causing injury. While DCD has been practiced for several years to retrieve organs such as the kidney, liver, lungs, and pancreas, the heart is more difficult as it is more susceptible to oxygen deprivation. And for the heart to be assessed for transplant suitability, it should ideally be beating, so it has to be reperfused and restarted quickly after death has been declared.

For many years it was thought the oxygen deprivation that occurs after circulatory death would be too much to provide a functional organ. But researchers in the United Kingdom and Australia developed techniques to overcome this problem, and early DCD heart transplants took place in 2014 in Australia, and in 2015 in the United Kingdom.

Heart transplantation after circulatory death has now become a routine part of the transplant program in many countries, including the United States, Spain, Belgium, the Netherlands, and Austria.

In the United States, 348 DCD heart transplants were performed in 2022, with numbers expected to reach 700 to 800 this year as more centers come online.

It is expected that most countries with heart transplant programs will follow suit and the number of donor hearts will increase by up to 30% worldwide because of DCD.  

Currently, there are about 8,000 heart transplants worldwide each year and with DCD this could rise to about 10,000, potentially an extra 2,000 lives saved each year, experts estimate.  

Two different approaches to DCD heart transplantation have been developed.
 

The direct procurement approach

The Australian group, based at St. Vincent’s Hospital in Sydney, developed a technique referred to as “direct procurement”: after the standoff period and declaration of circulatory death, the chest is opened, and the heart is removed. New technology, the Organ Care System (OCS) heart box (Transmedics), is then used to reperfuse and restart the heart outside the body so its suitability for transplant can be assessed.

The heart is kept perfused and beating in the OCS box while it is being transported to the recipient. This has enabled longer transit times than the traditional way of transporting the nonbeating heart on ice.

Peter MacDonald, MD, PhD, from the St Vincent’s group that developed this approach, said, “Most people thought a heart from a DCD donor would not survive transport – that the injury to the heart from the combination of life support withdrawal, stand-off time, and cold storage would be too much. But we modeled the process in the lab and were able to show that we were able to get the heart beating again after withdrawal of life support.”

Dr. McDonald noted that “the recipient of their first human DCD heart transplant using this machine in 2014 is still alive and well.” The Australian group has now done 85 of these DCD heart transplants, and they have increased the number of heart transplant procedures at St. Vincent’s Hospital by 25%.
 

Normothermic regional perfusion (NRP)  

The U.K. group, based at the Royal Papworth Hospital in Cambridge, England, developed a different approach to DCD: After the standoff period and the declaration of circulatory death, the donor is connected to a heart/lung machine using extracorporeal membrane oxygenation (ECMO) so that the heart is perfused and starts beating again inside the body. This approach is known as normothermic regional perfusion (NRP).

Marius Berman, MD, surgical lead for Transplantation and Mechanical Circulatory Support at Papworth, explained that the NRP approach allows the heart to be perfused and restarted faster than direct procurement, resulting in a shorter ischemic time. The heart can be evaluated thoroughly for suitability for transplantation in situ before committing to transplantation, and because the heart is less damaged, it can be transported on ice without use of the OCS box.

“DCD is more complicated than DBD, because the heart has stopped and has to be restarted. Retrieval teams have to be very experienced,” Dr. Berman noted. “This is more of an issue for the direct procurement approach, where the chest has to be opened and the heart retrieved as fast as possible. It is a rush. The longer time without the heart being perfused correlates to an increased incidence of primary graft dysfunction. With NRP, we can get the heart started again more quickly, which is crucial.”

Stephen Large, MBBS, another cardiothoracic surgeon with the Papworth team, added that they have reduced ischemic time to about 15 minutes. “That’s considerably shorter than reperfusing the heart outside the body,” he said. “This results in a healthier organ for the recipient.” 

The NRP approach is also less expensive than direct procurement as one OCS box costs about $75,000.

He pointed out that the NRP approach can also be used for heart transplants in children and even small babies, while currently the direct procurement technique is not typically suitable for children because the OCS box was not designed for small hearts. 

DCD, using either technique, has increased the heart transplant rate by 40% at Papworth, and is being used at all seven transplant centers in the United Kingdom, “a world first,” noted Dr. Large.

The Papworth team recently published its 5-year experience with 25 NRP transplants and 85 direct procurement transplants. Survival in recipients was no different, although there was some suggestion that the NRP hearts may have been in slightly better condition, possibly being more resistant to immunological rejection.
 

Ethical concerns about NRP

Restarting the circulation during the NRP process has raised ethical concerns.

When the NRP technique was first used in the United States, these ethical questions were raised by several groups, including the American College of Physicians (ACP).

Harry Peled, MD, Providence St. Jude Medical Center, Fullerton, Calif., coauthor of a recent Viewpoint on the issue, is board-certified in both cardiology and critical care, and said he is a supporter of DCD using direct procurement, but he does not believe that NRP is ethical at present. He is not part of the ACP, but said his views align with those of the organization.

There are two ethical problems with NRP, he said. The first is whether by restarting the circulation, the NRP process violates the U.S. definition of death, and retrieval of organs would therefore violate the dead donor rule. 

“American law states that death is the irreversible cessation of brain function or of circulatory function. But with NRP, the circulation is artificially restored, so the cessation of circulatory function is not irreversible,” Dr. Peled pointed out.

“I have no problem with DCD using direct procurement as we are not restarting the circulation. But NRP is restarting the circulation and that is a problem for me,” Dr. Peled said. “I would argue that by performing NRP, we are resuscitating the patient.”

The second ethical problem with NRP is concern about whether, during the process, there would be any circulation to the brain, and if so, would this be enough to restore some brain function? Before NRP is started, the main arch vessel arteries to the head are clamped to prevent flow to the brain, but there are worries that some blood flow may still be possible through small collateral vessels.

“We have established that these patients do not have enough brain function for a meaningful life, which is why a decision has been made to remove life support, but they have not been declared brain dead,” Dr. Peled said.

With direct procurement, the circulation is not restarted so there is no chance that any brain function will be restored, he said. “But with NRP, because the arch vessels have to be clamped to prevent brain circulation, that is admitting there is concern that brain function may be restored if circulation to the brain is reestablished, and brain function is compatible with life. As we do not know whether there is any meaningful circulation to the brain via the small collaterals, there is, in effect, a risk of bringing the patient back to life.”

The other major concern for some is whether even a very small amount of circulation to the brain would be enough to support consciousness, and “we don’t know that for certain,” Dr. Peled said.
 

The argument for NRP

Nader Moazami, MD, professor of cardiovascular surgery, NYU Langone Health, New York, is one of the more vocal proponents of NRP for DCD heart transplantation in the United States, and has coauthored responses to these ethical concerns.

“People are confusing many issues to produce an argument against NRP,” he said.

“Our position is that death has already been declared based on the lack of circulatory function for over 5 minutes and this has been with the full agreement of the family, knowing that the patient has no chance of a meaningful life. No one is thinking of trying to resuscitate the patient. It has already been established that any future efforts to resuscitate are futile. In this case, we are not resuscitating the patient by restarting the circulation. It is just regional perfusion of the organs.”

Dr. Moazami pointed out this concept was accepted for the practice of abdominal DCD when it first started in the United States in the 1990s where cold perfusion was used to preserve the abdominal organs before they were retrieved from the body.

“The new approach of using NRP is similar except that it involves circulating warm blood, which will preserve organs better and result in higher quality organs for the recipient.”

On the issue of concern about possible circulation to the brain, Dr. Moazami said: “The ethical critics of NRP are questioning whether the brain may not be dead. We are arguing that the patient has already been declared dead as they have had a circulatory death. You cannot die twice.”

He maintained that the clamping of the arch vessels to the head will ensure that when the circulation is restarted “the natural process of circulatory death leading to brain death will continue to progress.” 

On the concerns about possible collateral flow to the brain, Dr. Moazami said there is no evidence that this occurs. “Prominent neurologists have said it is impossible for collaterals to provide any meaningful blood flow to the brain in this situation. And even if there is small amount of blood flow to the brain, this would be insufficient to maintain any meaningful brain function.”

But Dr. Peled argues that this has not been proved. “Even though we don’t think there is enough circulation to the brain for any function with NRP, we don’t know that with 100% certainty,” he said. “In my view, if there is a possibility of even the smallest amount of brain flow, we are going against the dead donor rule. We are rewriting the rules of death.”

Dr. Moazami countered: “Nothing in life is 100%, particularly in medicine. With that argument can you also prove with 100% certainty to me that there is absolutely no brain function with regular direct procurement DCD?  We know that brain death has started, but the question is: Has it been completed? We don’t know the answer to this question with 100% certainty, but that is the case for regular direct procurement DCD as well, and that has been accepted by almost everyone.

“The whole issue revolves around when are we comfortable that death has occurred,” he said. “Those against NRP are concerned that organs are being taken before the patient is dead. But the key point is that the patient has already been declared dead.”

Since there is some concern over the ethics of NRP, why not just stick to DCD with direct procurement?

Dr. Moazami argued that NRP results in healthier organs. “NRP allows more successful heart transplants, liver transplants, lung transplants. It preserves all the organs better,” he said. “This will have a big impact on recipients – they would obviously much prefer a healthier organ. In addition, the process is easier and cheaper, so more centers will be able to do it, therefore more transplants will get done and more lives will be saved if NRP is used.”

He added: “I am a physician taking care of sick patients. I believe I have to respect the wishes of the donor and the donor family; make sure I’m not doing any harm to the donor; and ensure the best quality possible of the organ I am retrieving to best serve the recipient. I am happy I am doing this by using NRP for DCD heart transplantation.”

But Dr. Peled argued that while NRP may have some possible advantages over direct procurement, that does not justify allowing a process to go ahead that is unethical.

“The fact that NRP may result in some benefits doesn’t justify violating the dead donor rule or the possibility, however small, of causing pain to the donor. If it’s unethical, it’s unethical. Full stop,” he said.

“I feel that NRP is not respecting the rights of our patients and that the process does not have adequate transparency. We took it to our local ethics committee, and they decided not to approve NRP in our health care system. I agree with this decision,” Dr. Peled said.  

“The trouble is different experts and different countries are not in agreement about this,” he added. “Reasonable, well-informed people are in disagreement. I do not believe we can have a standard of care where there is not consensus.”
 

Cautious nod

In a 2022 consensus statement, the International Society for Heart and Lung Transplantation (ISHLT) gave a cautious nod toward DCD and NRP, dependent on local recommendations.

The ISHLT conclusion reads: “With appropriate consideration of the ethical principles involved in organ donation, DCD can be undertaken in a morally permissible manner. In all cases, the introduction of DCD programs should be in accordance with local legal regulations. Countries lacking a DCD pathway should be encouraged to develop national ethical, professional, and legal frameworks to address both public and professional concerns.”

The author of a recent editorial on the subject, Ulrich P. Jorde, MD, head of the heart transplant program at Montefiore Medical Center, New York, said, “DCD is a great step forward. People regularly die on the heart transplant waiting list. DCD will increase the supply of donor hearts by 20% to 30%.”

However, he noted that while most societies have agreed on a protocol for organ donation based on brain death, the situation is more complicated with circulatory death.

“Different countries have different definitions of circulatory death. How long do we have to wait after the heart has stopped beating before the patient is declared dead? Most countries have agreed on 5 minutes, but other countries have imposed different periods and as such, different definitions of death.

“The ISHLT statement says that restarting the circulation is acceptable if death has been certified according to prevailing law and surgical interventions are undertaken to preclude any restoration of cerebral circulation. But our problem is that different regional societies have different definitions of circulatory, death which makes the situation confusing.”

Dr. Jorde added: “We also have to weigh the wishes of the donor and their family. If family, advocating what are presumed to be the donor’s wishes, have decided that DCD would be acceptable and they understand the concept and wish to donate the organs after circulatory death, this should be strongly considered under the concept of self-determination, a basic human right.”
 

Variations in practice around the world 

This ethical debate has led to large variations in practice around the world, with some countries, such as Spain, allowing both methods of DCD, while Australia allows direct procurement but not NRP, and Germany currently does not allow DCD at all.

In the United States, things are even more complicated, with some states allowing NRP while others don’t. Even within states, some hospitals and transplant organizations allow NRP, and others don’t. 

David A. D’Alessandro, MD, cardiac surgeon at Massachusetts General Hospital, Boston, uses only the direct procurement approach as his region does not allow NRP.

“The direct procurement approach is not controversial and to me that’s a big advantage. I believe we need to agree on the ethics first, and then get into a debate about which technique is better,” he told this news organization.

Dr. D’Alessandro and his group recently published the results of their study, with direct procurement DCD heart transplantation showing similar short-term clinical outcomes to DBD.

“We are only doing direct procurement and we are seeing good results that appear to be comparable to DBD. That is good enough for me,” he said.

Dr. D’Alessandro estimates that in the United States both types of DCD procedures are currently being done about equally.

“Anything we can do to increase the amount of hearts available for transplantation is a big deal,” he said. “At the moment, only the very sickest patients get a heart transplant, and many patients die on the transplant waiting list. Very sadly, many young people die every year from a circulatory death after having life support withdrawn. Before DCD, these beautiful functional organs were not able to be used. Now we have a way of saving lives with these organs.”

Dr. D’Alessandro noted that more and more centers in the United States are starting to perform DCD heart transplants. 

“Not every transplant center may join in as the DCD procedures are very resource-intensive and time-consuming. For low-volume transplant centers, it may not be worth the expense and anguish to do DCD heart transplants. But bigger centers will need to engage in DCD to remain competitive. My guess is that 50%-70% of U.S. transplant centers will do DCD in future.”

He said he thinks it is a “medical shortcoming” that agreement cannot be reached on the ethics of NRP. “In an ideal world everyone would be on the same page. It makes me a bit uncomfortable that some people think it’s okay and some people don’t.”

Adam DeVore, MD, a cardiologist at Duke University Medical Center, Durham, N.C., the first U.S. center to perform an adult DCD heart transplant, reported that his institution uses both methods, with the choice sometimes depending on how far the heart must travel.

“If the recipient is near, NRP may be chosen as the heart is transported on ice, but if it needs to go further away we are more likely to choose direct procurement and use of the OCS box,” he said. 

“I am really proud of what we’ve been able to do, helping to introduce DCD in the U.S.,” Dr. DeVore said. “This is having a massive benefit in increasing the number of hearts for donation with great outcomes.”  

But he acknowledged that the whole concept of DCD is somewhat controversial.  

“The idea of brain death really came about for the purpose of heart donation. The two things are very intricately tied. Trying to do heart donation without brain death having been declared is foreign to people. Also, in DCD there is the issue of [this]: When life support is removed, how long do we wait before death can be declared? That could be in conflict with how long the organ needs to remain viable. We are going through the process now of looking at these questions. There is a lot of variation in the U.S. about the withdrawal of care and the declaration of death, which is not completely standardized.

“But the concept of circulatory death itself is accepted after the withdrawal of life support. I think it’s the rush to take the organs out that makes it more difficult.”

Dr. DeVore said the field is moving forward now. “As the process has become more common, people have become more comfortable, probably because of the big difference it will make to saving lives. But we do need to try and standardize best practices.”

A recent Canadian review of the ethics of DCD concluded that the direct procurement approach would be in alignment with current medical guidelines, but that further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.

In the United Kingdom, the definition of death is brain-based, and brain death is defined on a neurological basis.

Dr. Stephen Large from Papworth explained that this recognizes the presence of brain-stem death through brain stem reflex testing after the withdrawal of life support, cardiorespiratory arrest and 5 further minutes of ischemia. As long as NRP does not restore intracranial (brainstem) perfusion after death has been confirmed, then it is consistent with laws for death determination and therefore both direct procurement and NRP are permissible.

However, the question over possible collateral flow to the brain has led the United Kingdom to pause the NRP technique as routine practice while this is investigated further. So, at the present time, the vast majority of DCD heart transplants are being conducted using the direct procurement approach.

But the United Kingdom is facing the bigger challenge: national funding that will soon end. “The DCD program in the U.K. has been extremely successful, increasing heart transplant rates by up to 28%,” Dr. Berman said. “Everybody wants it to continue. But at present the DCD program only has national funding in the U.K. until March 2023. We don’t know what will happen after that.”

The current model in the United Kingdom consists of three specialized DCD heart retrieval teams, a national protocol of direct organ procurement and delivery of DCD hearts to all seven transplant programs, both adult and pediatric.

If the national funding is not extended, “we will go back to individual hospitals trying to fund their own programs. That will be a serious threat to the program and could result in a large reduction in heart transplants,” said Dr. Berman.
 

Definition of death  

The crux of the issue with regard to NRP seems to be variations in how death is defined and the interpretation of those definitions.  

DCD donors will have had many tests indicating severe brain damage, a neurologist will have declared the prognosis is futile, and relatives will have agreed to withdraw life support, Dr. Jorde said. “The heart stops beating, and the stand-off time means that blood flow to the brain ceases completely for at least 5 minutes before circulatory death is declared. This is enough on its own to stop brain function.”

Dr. Large made the point that by the time the circulation is reestablished with NRP, more time has elapsed, and the brain will have been without perfusion for much longer than 5 minutes, so it would be “physiologically almost impossible” for there to be any blood flow to the brain.

“Because these brains are already very damaged before life support was removed, the intracranial pressure is high, which will further discourage blood flow to the brain,” he said. Then the donor goes through a period of anoxic heart arrest, up to 16 minutes at a minimum of no blood supply, enough on its own to stop meaningful brain function. 

“It’s asking an awful lot to believe that there might be any brain function left,” he said. “And if, on reestablishing the circulation with NRP, there is any blood in the collaterals, the pressure of such flow is so low it won’t enter the brain.”

Dr. Large also pointed out that the fact that the United Kingdom requires a neurologic definition for brain-stem death makes the process easier. 

In Australia, St. Vincent’s cardiologist Dr. MacDonald noted that death is defined as the irreversible cessation of circulation, so the NRP procedure is not allowed.

“With NRP, there is an ethical dilemma over whether the patient has legally died or not. Different countries have different ways of defining death. Perhaps society will have to review of the definition of death,” he suggested. Death is a process, “but for organ donation, we have to choose a moment in time of that process that satisfies everyone – when there is no prospect of recovery of the donor but the organs can still be utilized without harming the donor.” 

Dr. MacDonald said the field is in transition. “I don’t want to argue that one technique is better than the other; I think it’s good to have access to both techniques. Anything that will increase the number of transplants we can do is a good thing.”
 

Collaborative decision

Everyone seems to agree that there should be an effort to try to define death in a uniform way worldwide, and that international, national and local regulations are aligned with each other.

Dr. Jorde said: “It is of critical importance that local guidelines are streamlined, firstly in any one given country and then globally, and these things must be discussed transparently within society with all stakeholders – doctors, patients, citizens.”

Dr. Peled, from Providence St. Jude in California, concurred: “There is the possibility that we could change the definition of death, but that cannot be a decision based solely on transplant organizations. It has to be a collaborative decision with a large input from groups who do not have an interest in the procurement of organs.”

He added: “The dialogue so far has been civil, and everybody is trying to do the right thing. My hope is that as a civilized society we will figure out a way forward. At present, there is significant controversy about NRP, and families need to know that. My main concern is that if there is any lack of transparency in getting informed consent, then this risks people losing trust in the donation system.” 

Dr. Moazami, from NYU Langone, said the controversy has cast a cloud over the practice of NRP throughout the world. “We need to get it sorted out.”

He said he believes the way forward is to settle the question of whether there is any meaningful blood flow to the brain with the NRP technique.

“This is where the research has to focus. I believe this concern is hypothetical, but I am happy to do the studies to confirm that. Then, the issue should come to a rest. I think that is the right way forward – to do the studies rather than enforcing a moratorium on the practice because of a hypothetical concern.”

These studies on blood flow to the brain are now getting started in both the United Kingdom and the United States.

The U.K. study is being run by Antonio Rubino, MD, consultant in cardiothoracic anesthesia and intensive care at Papworth Hospital NHS Foundation and clinical lead, organ donation. Dr. Rubino explained that the study will assess cerebral blood flow using CT angiography of the brain. “We hypothesize that this will provide evidence to indicate that brain blood flow is not present during NRP and promote trust in the use of NRP in routine practice,” he said.

Dr. Large said: “Rather than having these tortured arguments, we will do the measurements. For the sake of society in this situation, I think it’s good to stop and take a breath. We must measure this, and we are doing just that.”

If there is any blood flow at all, Dr. Large said they will then have to seek expert guidance. “Say we find there is 50 mL of blood flow and normal blood flow is 1,500 mL/min. We will need expert guidance on whether it is remotely possible to be sentient on that. I would say it would be extraordinarily unlikely.”  

Dr. Berman summarized the situation: “DCD is increasing the availability of hearts for transplant. This is saving lives, reducing the number of patients on the waiting list, and reducing hospital stays for patients unable to leave the hospital without a transplant. It is definitely here to stay. It is crucial that it gets funded properly, and it is also crucial that we resolve the NRP ethical issues as soon as possible.”

He is hopeful that some of these issues will be resolved this year.

Dr. MacDonald reported he has received “in-kind” support from Transmedics through provision of research modules for preclinical research studies. Dr. D’Alessandro reported he is on the speakers bureau for Abiomed, not relevant to this article. No other relevant disclosures were reported.
 

A version of this article first appeared on Medscape.com.

The relatively recent innovation of heart transplantation after circulatory death of the donor is increasing the number of donor hearts available and leading to many more lives on the heart transplant waiting list being saved. Experts agree it’s a major and very welcome advance in medicine.

However, some of the processes involved in one approach to donation after circulatory death has raised ethical concerns and questions about whether they violate the “dead donor rule” – a principle that requires patients be declared dead before removal of life-sustaining organs for transplant.  

Rasi Bhadramani/iStock/Getty Images

Experts in the fields of transplantation and medical ethics have yet to reach consensus, causing problems for the transplant community, who worry that this could cause a loss of confidence in the entire transplant process.
 

A new pathway for heart transplantation

The traditional approach to transplantation is to retrieve organs from a donor who has been declared brain dead, known as “donation after brain death (DBD).” These patients have usually suffered a catastrophic brain injury but survived to get to intensive care.

As the brain swells because of injury, it becomes evident that all brain function is lost, and the patient is declared brain dead. However, breathing is maintained by the ventilator and the heart is still beating. Because the organs are being oxygenated, there is no immediate rush to retrieve the organs and the heart can be evaluated for its suitability for transplant in a calm and methodical way before it is removed.  

However, there is a massive shortage of organs, especially hearts, partially because of the limited number of donors who are declared brain dead in that setting.

In recent years, another pathway for organ transplantation has become available: “donation after circulatory death (DCD).” These patients also have suffered a catastrophic brain injury considered to be nonsurvivable, but unlike the DBD situation, the brain still has some function, so the patient does not meet the criteria for brain death. 

Still, because the patient is considered to have no chance of a meaningful recovery, the family often recognizes the futility of treatment and agrees to the withdrawal of life support. When this happens, the heart normally stops beating after a period of time. There is then a “stand-off time” – normally 5 minutes – after which death is declared and the organs can be removed. 

The difficulty with this approach, however, is that because the heart has been stopped, it has been deprived of oxygen, potentially causing injury. While DCD has been practiced for several years to retrieve organs such as the kidney, liver, lungs, and pancreas, the heart is more difficult as it is more susceptible to oxygen deprivation. And for the heart to be assessed for transplant suitability, it should ideally be beating, so it has to be reperfused and restarted quickly after death has been declared.

For many years it was thought the oxygen deprivation that occurs after circulatory death would be too much to provide a functional organ. But researchers in the United Kingdom and Australia developed techniques to overcome this problem, and early DCD heart transplants took place in 2014 in Australia, and in 2015 in the United Kingdom.

Heart transplantation after circulatory death has now become a routine part of the transplant program in many countries, including the United States, Spain, Belgium, the Netherlands, and Austria.

In the United States, 348 DCD heart transplants were performed in 2022, with numbers expected to reach 700 to 800 this year as more centers come online.

It is expected that most countries with heart transplant programs will follow suit and the number of donor hearts will increase by up to 30% worldwide because of DCD.  

Currently, there are about 8,000 heart transplants worldwide each year and with DCD this could rise to about 10,000, potentially an extra 2,000 lives saved each year, experts estimate.  

Two different approaches to DCD heart transplantation have been developed.
 

The direct procurement approach

The Australian group, based at St. Vincent’s Hospital in Sydney, developed a technique referred to as “direct procurement”: after the standoff period and declaration of circulatory death, the chest is opened, and the heart is removed. New technology, the Organ Care System (OCS) heart box (Transmedics), is then used to reperfuse and restart the heart outside the body so its suitability for transplant can be assessed.

The heart is kept perfused and beating in the OCS box while it is being transported to the recipient. This has enabled longer transit times than the traditional way of transporting the nonbeating heart on ice.

Peter MacDonald, MD, PhD, from the St Vincent’s group that developed this approach, said, “Most people thought a heart from a DCD donor would not survive transport – that the injury to the heart from the combination of life support withdrawal, stand-off time, and cold storage would be too much. But we modeled the process in the lab and were able to show that we were able to get the heart beating again after withdrawal of life support.”

Dr. McDonald noted that “the recipient of their first human DCD heart transplant using this machine in 2014 is still alive and well.” The Australian group has now done 85 of these DCD heart transplants, and they have increased the number of heart transplant procedures at St. Vincent’s Hospital by 25%.
 

Normothermic regional perfusion (NRP)  

The U.K. group, based at the Royal Papworth Hospital in Cambridge, England, developed a different approach to DCD: After the standoff period and the declaration of circulatory death, the donor is connected to a heart/lung machine using extracorporeal membrane oxygenation (ECMO) so that the heart is perfused and starts beating again inside the body. This approach is known as normothermic regional perfusion (NRP).

Marius Berman, MD, surgical lead for Transplantation and Mechanical Circulatory Support at Papworth, explained that the NRP approach allows the heart to be perfused and restarted faster than direct procurement, resulting in a shorter ischemic time. The heart can be evaluated thoroughly for suitability for transplantation in situ before committing to transplantation, and because the heart is less damaged, it can be transported on ice without use of the OCS box.

“DCD is more complicated than DBD, because the heart has stopped and has to be restarted. Retrieval teams have to be very experienced,” Dr. Berman noted. “This is more of an issue for the direct procurement approach, where the chest has to be opened and the heart retrieved as fast as possible. It is a rush. The longer time without the heart being perfused correlates to an increased incidence of primary graft dysfunction. With NRP, we can get the heart started again more quickly, which is crucial.”

Stephen Large, MBBS, another cardiothoracic surgeon with the Papworth team, added that they have reduced ischemic time to about 15 minutes. “That’s considerably shorter than reperfusing the heart outside the body,” he said. “This results in a healthier organ for the recipient.” 

The NRP approach is also less expensive than direct procurement as one OCS box costs about $75,000.

He pointed out that the NRP approach can also be used for heart transplants in children and even small babies, while currently the direct procurement technique is not typically suitable for children because the OCS box was not designed for small hearts. 

DCD, using either technique, has increased the heart transplant rate by 40% at Papworth, and is being used at all seven transplant centers in the United Kingdom, “a world first,” noted Dr. Large.

The Papworth team recently published its 5-year experience with 25 NRP transplants and 85 direct procurement transplants. Survival in recipients was no different, although there was some suggestion that the NRP hearts may have been in slightly better condition, possibly being more resistant to immunological rejection.
 

Ethical concerns about NRP

Restarting the circulation during the NRP process has raised ethical concerns.

When the NRP technique was first used in the United States, these ethical questions were raised by several groups, including the American College of Physicians (ACP).

Harry Peled, MD, Providence St. Jude Medical Center, Fullerton, Calif., coauthor of a recent Viewpoint on the issue, is board-certified in both cardiology and critical care, and said he is a supporter of DCD using direct procurement, but he does not believe that NRP is ethical at present. He is not part of the ACP, but said his views align with those of the organization.

There are two ethical problems with NRP, he said. The first is whether by restarting the circulation, the NRP process violates the U.S. definition of death, and retrieval of organs would therefore violate the dead donor rule. 

“American law states that death is the irreversible cessation of brain function or of circulatory function. But with NRP, the circulation is artificially restored, so the cessation of circulatory function is not irreversible,” Dr. Peled pointed out.

“I have no problem with DCD using direct procurement as we are not restarting the circulation. But NRP is restarting the circulation and that is a problem for me,” Dr. Peled said. “I would argue that by performing NRP, we are resuscitating the patient.”

The second ethical problem with NRP is concern about whether, during the process, there would be any circulation to the brain, and if so, would this be enough to restore some brain function? Before NRP is started, the main arch vessel arteries to the head are clamped to prevent flow to the brain, but there are worries that some blood flow may still be possible through small collateral vessels.

“We have established that these patients do not have enough brain function for a meaningful life, which is why a decision has been made to remove life support, but they have not been declared brain dead,” Dr. Peled said.

With direct procurement, the circulation is not restarted so there is no chance that any brain function will be restored, he said. “But with NRP, because the arch vessels have to be clamped to prevent brain circulation, that is admitting there is concern that brain function may be restored if circulation to the brain is reestablished, and brain function is compatible with life. As we do not know whether there is any meaningful circulation to the brain via the small collaterals, there is, in effect, a risk of bringing the patient back to life.”

The other major concern for some is whether even a very small amount of circulation to the brain would be enough to support consciousness, and “we don’t know that for certain,” Dr. Peled said.
 

The argument for NRP

Nader Moazami, MD, professor of cardiovascular surgery, NYU Langone Health, New York, is one of the more vocal proponents of NRP for DCD heart transplantation in the United States, and has coauthored responses to these ethical concerns.

“People are confusing many issues to produce an argument against NRP,” he said.

“Our position is that death has already been declared based on the lack of circulatory function for over 5 minutes and this has been with the full agreement of the family, knowing that the patient has no chance of a meaningful life. No one is thinking of trying to resuscitate the patient. It has already been established that any future efforts to resuscitate are futile. In this case, we are not resuscitating the patient by restarting the circulation. It is just regional perfusion of the organs.”

Dr. Moazami pointed out this concept was accepted for the practice of abdominal DCD when it first started in the United States in the 1990s where cold perfusion was used to preserve the abdominal organs before they were retrieved from the body.

“The new approach of using NRP is similar except that it involves circulating warm blood, which will preserve organs better and result in higher quality organs for the recipient.”

On the issue of concern about possible circulation to the brain, Dr. Moazami said: “The ethical critics of NRP are questioning whether the brain may not be dead. We are arguing that the patient has already been declared dead as they have had a circulatory death. You cannot die twice.”

He maintained that the clamping of the arch vessels to the head will ensure that when the circulation is restarted “the natural process of circulatory death leading to brain death will continue to progress.” 

On the concerns about possible collateral flow to the brain, Dr. Moazami said there is no evidence that this occurs. “Prominent neurologists have said it is impossible for collaterals to provide any meaningful blood flow to the brain in this situation. And even if there is small amount of blood flow to the brain, this would be insufficient to maintain any meaningful brain function.”

But Dr. Peled argues that this has not been proved. “Even though we don’t think there is enough circulation to the brain for any function with NRP, we don’t know that with 100% certainty,” he said. “In my view, if there is a possibility of even the smallest amount of brain flow, we are going against the dead donor rule. We are rewriting the rules of death.”

Dr. Moazami countered: “Nothing in life is 100%, particularly in medicine. With that argument can you also prove with 100% certainty to me that there is absolutely no brain function with regular direct procurement DCD?  We know that brain death has started, but the question is: Has it been completed? We don’t know the answer to this question with 100% certainty, but that is the case for regular direct procurement DCD as well, and that has been accepted by almost everyone.

“The whole issue revolves around when are we comfortable that death has occurred,” he said. “Those against NRP are concerned that organs are being taken before the patient is dead. But the key point is that the patient has already been declared dead.”

Since there is some concern over the ethics of NRP, why not just stick to DCD with direct procurement?

Dr. Moazami argued that NRP results in healthier organs. “NRP allows more successful heart transplants, liver transplants, lung transplants. It preserves all the organs better,” he said. “This will have a big impact on recipients – they would obviously much prefer a healthier organ. In addition, the process is easier and cheaper, so more centers will be able to do it, therefore more transplants will get done and more lives will be saved if NRP is used.”

He added: “I am a physician taking care of sick patients. I believe I have to respect the wishes of the donor and the donor family; make sure I’m not doing any harm to the donor; and ensure the best quality possible of the organ I am retrieving to best serve the recipient. I am happy I am doing this by using NRP for DCD heart transplantation.”

But Dr. Peled argued that while NRP may have some possible advantages over direct procurement, that does not justify allowing a process to go ahead that is unethical.

“The fact that NRP may result in some benefits doesn’t justify violating the dead donor rule or the possibility, however small, of causing pain to the donor. If it’s unethical, it’s unethical. Full stop,” he said.

“I feel that NRP is not respecting the rights of our patients and that the process does not have adequate transparency. We took it to our local ethics committee, and they decided not to approve NRP in our health care system. I agree with this decision,” Dr. Peled said.  

“The trouble is different experts and different countries are not in agreement about this,” he added. “Reasonable, well-informed people are in disagreement. I do not believe we can have a standard of care where there is not consensus.”
 

Cautious nod

In a 2022 consensus statement, the International Society for Heart and Lung Transplantation (ISHLT) gave a cautious nod toward DCD and NRP, dependent on local recommendations.

The ISHLT conclusion reads: “With appropriate consideration of the ethical principles involved in organ donation, DCD can be undertaken in a morally permissible manner. In all cases, the introduction of DCD programs should be in accordance with local legal regulations. Countries lacking a DCD pathway should be encouraged to develop national ethical, professional, and legal frameworks to address both public and professional concerns.”

The author of a recent editorial on the subject, Ulrich P. Jorde, MD, head of the heart transplant program at Montefiore Medical Center, New York, said, “DCD is a great step forward. People regularly die on the heart transplant waiting list. DCD will increase the supply of donor hearts by 20% to 30%.”

However, he noted that while most societies have agreed on a protocol for organ donation based on brain death, the situation is more complicated with circulatory death.

“Different countries have different definitions of circulatory death. How long do we have to wait after the heart has stopped beating before the patient is declared dead? Most countries have agreed on 5 minutes, but other countries have imposed different periods and as such, different definitions of death.

“The ISHLT statement says that restarting the circulation is acceptable if death has been certified according to prevailing law and surgical interventions are undertaken to preclude any restoration of cerebral circulation. But our problem is that different regional societies have different definitions of circulatory, death which makes the situation confusing.”

Dr. Jorde added: “We also have to weigh the wishes of the donor and their family. If family, advocating what are presumed to be the donor’s wishes, have decided that DCD would be acceptable and they understand the concept and wish to donate the organs after circulatory death, this should be strongly considered under the concept of self-determination, a basic human right.”
 

Variations in practice around the world 

This ethical debate has led to large variations in practice around the world, with some countries, such as Spain, allowing both methods of DCD, while Australia allows direct procurement but not NRP, and Germany currently does not allow DCD at all.

In the United States, things are even more complicated, with some states allowing NRP while others don’t. Even within states, some hospitals and transplant organizations allow NRP, and others don’t. 

David A. D’Alessandro, MD, cardiac surgeon at Massachusetts General Hospital, Boston, uses only the direct procurement approach as his region does not allow NRP.

“The direct procurement approach is not controversial and to me that’s a big advantage. I believe we need to agree on the ethics first, and then get into a debate about which technique is better,” he told this news organization.

Dr. D’Alessandro and his group recently published the results of their study, with direct procurement DCD heart transplantation showing similar short-term clinical outcomes to DBD.

“We are only doing direct procurement and we are seeing good results that appear to be comparable to DBD. That is good enough for me,” he said.

Dr. D’Alessandro estimates that in the United States both types of DCD procedures are currently being done about equally.

“Anything we can do to increase the amount of hearts available for transplantation is a big deal,” he said. “At the moment, only the very sickest patients get a heart transplant, and many patients die on the transplant waiting list. Very sadly, many young people die every year from a circulatory death after having life support withdrawn. Before DCD, these beautiful functional organs were not able to be used. Now we have a way of saving lives with these organs.”

Dr. D’Alessandro noted that more and more centers in the United States are starting to perform DCD heart transplants. 

“Not every transplant center may join in as the DCD procedures are very resource-intensive and time-consuming. For low-volume transplant centers, it may not be worth the expense and anguish to do DCD heart transplants. But bigger centers will need to engage in DCD to remain competitive. My guess is that 50%-70% of U.S. transplant centers will do DCD in future.”

He said he thinks it is a “medical shortcoming” that agreement cannot be reached on the ethics of NRP. “In an ideal world everyone would be on the same page. It makes me a bit uncomfortable that some people think it’s okay and some people don’t.”

Adam DeVore, MD, a cardiologist at Duke University Medical Center, Durham, N.C., the first U.S. center to perform an adult DCD heart transplant, reported that his institution uses both methods, with the choice sometimes depending on how far the heart must travel.

“If the recipient is near, NRP may be chosen as the heart is transported on ice, but if it needs to go further away we are more likely to choose direct procurement and use of the OCS box,” he said. 

“I am really proud of what we’ve been able to do, helping to introduce DCD in the U.S.,” Dr. DeVore said. “This is having a massive benefit in increasing the number of hearts for donation with great outcomes.”  

But he acknowledged that the whole concept of DCD is somewhat controversial.  

“The idea of brain death really came about for the purpose of heart donation. The two things are very intricately tied. Trying to do heart donation without brain death having been declared is foreign to people. Also, in DCD there is the issue of [this]: When life support is removed, how long do we wait before death can be declared? That could be in conflict with how long the organ needs to remain viable. We are going through the process now of looking at these questions. There is a lot of variation in the U.S. about the withdrawal of care and the declaration of death, which is not completely standardized.

“But the concept of circulatory death itself is accepted after the withdrawal of life support. I think it’s the rush to take the organs out that makes it more difficult.”

Dr. DeVore said the field is moving forward now. “As the process has become more common, people have become more comfortable, probably because of the big difference it will make to saving lives. But we do need to try and standardize best practices.”

A recent Canadian review of the ethics of DCD concluded that the direct procurement approach would be in alignment with current medical guidelines, but that further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.

In the United Kingdom, the definition of death is brain-based, and brain death is defined on a neurological basis.

Dr. Stephen Large from Papworth explained that this recognizes the presence of brain-stem death through brain stem reflex testing after the withdrawal of life support, cardiorespiratory arrest and 5 further minutes of ischemia. As long as NRP does not restore intracranial (brainstem) perfusion after death has been confirmed, then it is consistent with laws for death determination and therefore both direct procurement and NRP are permissible.

However, the question over possible collateral flow to the brain has led the United Kingdom to pause the NRP technique as routine practice while this is investigated further. So, at the present time, the vast majority of DCD heart transplants are being conducted using the direct procurement approach.

But the United Kingdom is facing the bigger challenge: national funding that will soon end. “The DCD program in the U.K. has been extremely successful, increasing heart transplant rates by up to 28%,” Dr. Berman said. “Everybody wants it to continue. But at present the DCD program only has national funding in the U.K. until March 2023. We don’t know what will happen after that.”

The current model in the United Kingdom consists of three specialized DCD heart retrieval teams, a national protocol of direct organ procurement and delivery of DCD hearts to all seven transplant programs, both adult and pediatric.

If the national funding is not extended, “we will go back to individual hospitals trying to fund their own programs. That will be a serious threat to the program and could result in a large reduction in heart transplants,” said Dr. Berman.
 

Definition of death  

The crux of the issue with regard to NRP seems to be variations in how death is defined and the interpretation of those definitions.  

DCD donors will have had many tests indicating severe brain damage, a neurologist will have declared the prognosis is futile, and relatives will have agreed to withdraw life support, Dr. Jorde said. “The heart stops beating, and the stand-off time means that blood flow to the brain ceases completely for at least 5 minutes before circulatory death is declared. This is enough on its own to stop brain function.”

Dr. Large made the point that by the time the circulation is reestablished with NRP, more time has elapsed, and the brain will have been without perfusion for much longer than 5 minutes, so it would be “physiologically almost impossible” for there to be any blood flow to the brain.

“Because these brains are already very damaged before life support was removed, the intracranial pressure is high, which will further discourage blood flow to the brain,” he said. Then the donor goes through a period of anoxic heart arrest, up to 16 minutes at a minimum of no blood supply, enough on its own to stop meaningful brain function. 

“It’s asking an awful lot to believe that there might be any brain function left,” he said. “And if, on reestablishing the circulation with NRP, there is any blood in the collaterals, the pressure of such flow is so low it won’t enter the brain.”

Dr. Large also pointed out that the fact that the United Kingdom requires a neurologic definition for brain-stem death makes the process easier. 

In Australia, St. Vincent’s cardiologist Dr. MacDonald noted that death is defined as the irreversible cessation of circulation, so the NRP procedure is not allowed.

“With NRP, there is an ethical dilemma over whether the patient has legally died or not. Different countries have different ways of defining death. Perhaps society will have to review of the definition of death,” he suggested. Death is a process, “but for organ donation, we have to choose a moment in time of that process that satisfies everyone – when there is no prospect of recovery of the donor but the organs can still be utilized without harming the donor.” 

Dr. MacDonald said the field is in transition. “I don’t want to argue that one technique is better than the other; I think it’s good to have access to both techniques. Anything that will increase the number of transplants we can do is a good thing.”
 

Collaborative decision

Everyone seems to agree that there should be an effort to try to define death in a uniform way worldwide, and that international, national and local regulations are aligned with each other.

Dr. Jorde said: “It is of critical importance that local guidelines are streamlined, firstly in any one given country and then globally, and these things must be discussed transparently within society with all stakeholders – doctors, patients, citizens.”

Dr. Peled, from Providence St. Jude in California, concurred: “There is the possibility that we could change the definition of death, but that cannot be a decision based solely on transplant organizations. It has to be a collaborative decision with a large input from groups who do not have an interest in the procurement of organs.”

He added: “The dialogue so far has been civil, and everybody is trying to do the right thing. My hope is that as a civilized society we will figure out a way forward. At present, there is significant controversy about NRP, and families need to know that. My main concern is that if there is any lack of transparency in getting informed consent, then this risks people losing trust in the donation system.” 

Dr. Moazami, from NYU Langone, said the controversy has cast a cloud over the practice of NRP throughout the world. “We need to get it sorted out.”

He said he believes the way forward is to settle the question of whether there is any meaningful blood flow to the brain with the NRP technique.

“This is where the research has to focus. I believe this concern is hypothetical, but I am happy to do the studies to confirm that. Then, the issue should come to a rest. I think that is the right way forward – to do the studies rather than enforcing a moratorium on the practice because of a hypothetical concern.”

These studies on blood flow to the brain are now getting started in both the United Kingdom and the United States.

The U.K. study is being run by Antonio Rubino, MD, consultant in cardiothoracic anesthesia and intensive care at Papworth Hospital NHS Foundation and clinical lead, organ donation. Dr. Rubino explained that the study will assess cerebral blood flow using CT angiography of the brain. “We hypothesize that this will provide evidence to indicate that brain blood flow is not present during NRP and promote trust in the use of NRP in routine practice,” he said.

Dr. Large said: “Rather than having these tortured arguments, we will do the measurements. For the sake of society in this situation, I think it’s good to stop and take a breath. We must measure this, and we are doing just that.”

If there is any blood flow at all, Dr. Large said they will then have to seek expert guidance. “Say we find there is 50 mL of blood flow and normal blood flow is 1,500 mL/min. We will need expert guidance on whether it is remotely possible to be sentient on that. I would say it would be extraordinarily unlikely.”  

Dr. Berman summarized the situation: “DCD is increasing the availability of hearts for transplant. This is saving lives, reducing the number of patients on the waiting list, and reducing hospital stays for patients unable to leave the hospital without a transplant. It is definitely here to stay. It is crucial that it gets funded properly, and it is also crucial that we resolve the NRP ethical issues as soon as possible.”

He is hopeful that some of these issues will be resolved this year.

Dr. MacDonald reported he has received “in-kind” support from Transmedics through provision of research modules for preclinical research studies. Dr. D’Alessandro reported he is on the speakers bureau for Abiomed, not relevant to this article. No other relevant disclosures were reported.
 

A version of this article first appeared on Medscape.com.

The relatively recent innovation of heart transplantation after circulatory death of the donor is increasing the number of donor hearts available and leading to many more lives on the heart transplant waiting list being saved. Experts agree it’s a major and very welcome advance in medicine.

However, some of the processes involved in one approach to donation after circulatory death has raised ethical concerns and questions about whether they violate the “dead donor rule” – a principle that requires patients be declared dead before removal of life-sustaining organs for transplant.  

Rasi Bhadramani/iStock/Getty Images

Experts in the fields of transplantation and medical ethics have yet to reach consensus, causing problems for the transplant community, who worry that this could cause a loss of confidence in the entire transplant process.
 

A new pathway for heart transplantation

The traditional approach to transplantation is to retrieve organs from a donor who has been declared brain dead, known as “donation after brain death (DBD).” These patients have usually suffered a catastrophic brain injury but survived to get to intensive care.

As the brain swells because of injury, it becomes evident that all brain function is lost, and the patient is declared brain dead. However, breathing is maintained by the ventilator and the heart is still beating. Because the organs are being oxygenated, there is no immediate rush to retrieve the organs and the heart can be evaluated for its suitability for transplant in a calm and methodical way before it is removed.  

However, there is a massive shortage of organs, especially hearts, partially because of the limited number of donors who are declared brain dead in that setting.

In recent years, another pathway for organ transplantation has become available: “donation after circulatory death (DCD).” These patients also have suffered a catastrophic brain injury considered to be nonsurvivable, but unlike the DBD situation, the brain still has some function, so the patient does not meet the criteria for brain death. 

Still, because the patient is considered to have no chance of a meaningful recovery, the family often recognizes the futility of treatment and agrees to the withdrawal of life support. When this happens, the heart normally stops beating after a period of time. There is then a “stand-off time” – normally 5 minutes – after which death is declared and the organs can be removed. 

The difficulty with this approach, however, is that because the heart has been stopped, it has been deprived of oxygen, potentially causing injury. While DCD has been practiced for several years to retrieve organs such as the kidney, liver, lungs, and pancreas, the heart is more difficult as it is more susceptible to oxygen deprivation. And for the heart to be assessed for transplant suitability, it should ideally be beating, so it has to be reperfused and restarted quickly after death has been declared.

For many years it was thought the oxygen deprivation that occurs after circulatory death would be too much to provide a functional organ. But researchers in the United Kingdom and Australia developed techniques to overcome this problem, and early DCD heart transplants took place in 2014 in Australia, and in 2015 in the United Kingdom.

Heart transplantation after circulatory death has now become a routine part of the transplant program in many countries, including the United States, Spain, Belgium, the Netherlands, and Austria.

In the United States, 348 DCD heart transplants were performed in 2022, with numbers expected to reach 700 to 800 this year as more centers come online.

It is expected that most countries with heart transplant programs will follow suit and the number of donor hearts will increase by up to 30% worldwide because of DCD.  

Currently, there are about 8,000 heart transplants worldwide each year and with DCD this could rise to about 10,000, potentially an extra 2,000 lives saved each year, experts estimate.  

Two different approaches to DCD heart transplantation have been developed.
 

The direct procurement approach

The Australian group, based at St. Vincent’s Hospital in Sydney, developed a technique referred to as “direct procurement”: after the standoff period and declaration of circulatory death, the chest is opened, and the heart is removed. New technology, the Organ Care System (OCS) heart box (Transmedics), is then used to reperfuse and restart the heart outside the body so its suitability for transplant can be assessed.

The heart is kept perfused and beating in the OCS box while it is being transported to the recipient. This has enabled longer transit times than the traditional way of transporting the nonbeating heart on ice.

Peter MacDonald, MD, PhD, from the St Vincent’s group that developed this approach, said, “Most people thought a heart from a DCD donor would not survive transport – that the injury to the heart from the combination of life support withdrawal, stand-off time, and cold storage would be too much. But we modeled the process in the lab and were able to show that we were able to get the heart beating again after withdrawal of life support.”

Dr. McDonald noted that “the recipient of their first human DCD heart transplant using this machine in 2014 is still alive and well.” The Australian group has now done 85 of these DCD heart transplants, and they have increased the number of heart transplant procedures at St. Vincent’s Hospital by 25%.
 

Normothermic regional perfusion (NRP)  

The U.K. group, based at the Royal Papworth Hospital in Cambridge, England, developed a different approach to DCD: After the standoff period and the declaration of circulatory death, the donor is connected to a heart/lung machine using extracorporeal membrane oxygenation (ECMO) so that the heart is perfused and starts beating again inside the body. This approach is known as normothermic regional perfusion (NRP).

Marius Berman, MD, surgical lead for Transplantation and Mechanical Circulatory Support at Papworth, explained that the NRP approach allows the heart to be perfused and restarted faster than direct procurement, resulting in a shorter ischemic time. The heart can be evaluated thoroughly for suitability for transplantation in situ before committing to transplantation, and because the heart is less damaged, it can be transported on ice without use of the OCS box.

“DCD is more complicated than DBD, because the heart has stopped and has to be restarted. Retrieval teams have to be very experienced,” Dr. Berman noted. “This is more of an issue for the direct procurement approach, where the chest has to be opened and the heart retrieved as fast as possible. It is a rush. The longer time without the heart being perfused correlates to an increased incidence of primary graft dysfunction. With NRP, we can get the heart started again more quickly, which is crucial.”

Stephen Large, MBBS, another cardiothoracic surgeon with the Papworth team, added that they have reduced ischemic time to about 15 minutes. “That’s considerably shorter than reperfusing the heart outside the body,” he said. “This results in a healthier organ for the recipient.” 

The NRP approach is also less expensive than direct procurement as one OCS box costs about $75,000.

He pointed out that the NRP approach can also be used for heart transplants in children and even small babies, while currently the direct procurement technique is not typically suitable for children because the OCS box was not designed for small hearts. 

DCD, using either technique, has increased the heart transplant rate by 40% at Papworth, and is being used at all seven transplant centers in the United Kingdom, “a world first,” noted Dr. Large.

The Papworth team recently published its 5-year experience with 25 NRP transplants and 85 direct procurement transplants. Survival in recipients was no different, although there was some suggestion that the NRP hearts may have been in slightly better condition, possibly being more resistant to immunological rejection.
 

Ethical concerns about NRP

Restarting the circulation during the NRP process has raised ethical concerns.

When the NRP technique was first used in the United States, these ethical questions were raised by several groups, including the American College of Physicians (ACP).

Harry Peled, MD, Providence St. Jude Medical Center, Fullerton, Calif., coauthor of a recent Viewpoint on the issue, is board-certified in both cardiology and critical care, and said he is a supporter of DCD using direct procurement, but he does not believe that NRP is ethical at present. He is not part of the ACP, but said his views align with those of the organization.

There are two ethical problems with NRP, he said. The first is whether by restarting the circulation, the NRP process violates the U.S. definition of death, and retrieval of organs would therefore violate the dead donor rule. 

“American law states that death is the irreversible cessation of brain function or of circulatory function. But with NRP, the circulation is artificially restored, so the cessation of circulatory function is not irreversible,” Dr. Peled pointed out.

“I have no problem with DCD using direct procurement as we are not restarting the circulation. But NRP is restarting the circulation and that is a problem for me,” Dr. Peled said. “I would argue that by performing NRP, we are resuscitating the patient.”

The second ethical problem with NRP is concern about whether, during the process, there would be any circulation to the brain, and if so, would this be enough to restore some brain function? Before NRP is started, the main arch vessel arteries to the head are clamped to prevent flow to the brain, but there are worries that some blood flow may still be possible through small collateral vessels.

“We have established that these patients do not have enough brain function for a meaningful life, which is why a decision has been made to remove life support, but they have not been declared brain dead,” Dr. Peled said.

With direct procurement, the circulation is not restarted so there is no chance that any brain function will be restored, he said. “But with NRP, because the arch vessels have to be clamped to prevent brain circulation, that is admitting there is concern that brain function may be restored if circulation to the brain is reestablished, and brain function is compatible with life. As we do not know whether there is any meaningful circulation to the brain via the small collaterals, there is, in effect, a risk of bringing the patient back to life.”

The other major concern for some is whether even a very small amount of circulation to the brain would be enough to support consciousness, and “we don’t know that for certain,” Dr. Peled said.
 

The argument for NRP

Nader Moazami, MD, professor of cardiovascular surgery, NYU Langone Health, New York, is one of the more vocal proponents of NRP for DCD heart transplantation in the United States, and has coauthored responses to these ethical concerns.

“People are confusing many issues to produce an argument against NRP,” he said.

“Our position is that death has already been declared based on the lack of circulatory function for over 5 minutes and this has been with the full agreement of the family, knowing that the patient has no chance of a meaningful life. No one is thinking of trying to resuscitate the patient. It has already been established that any future efforts to resuscitate are futile. In this case, we are not resuscitating the patient by restarting the circulation. It is just regional perfusion of the organs.”

Dr. Moazami pointed out this concept was accepted for the practice of abdominal DCD when it first started in the United States in the 1990s where cold perfusion was used to preserve the abdominal organs before they were retrieved from the body.

“The new approach of using NRP is similar except that it involves circulating warm blood, which will preserve organs better and result in higher quality organs for the recipient.”

On the issue of concern about possible circulation to the brain, Dr. Moazami said: “The ethical critics of NRP are questioning whether the brain may not be dead. We are arguing that the patient has already been declared dead as they have had a circulatory death. You cannot die twice.”

He maintained that the clamping of the arch vessels to the head will ensure that when the circulation is restarted “the natural process of circulatory death leading to brain death will continue to progress.” 

On the concerns about possible collateral flow to the brain, Dr. Moazami said there is no evidence that this occurs. “Prominent neurologists have said it is impossible for collaterals to provide any meaningful blood flow to the brain in this situation. And even if there is small amount of blood flow to the brain, this would be insufficient to maintain any meaningful brain function.”

But Dr. Peled argues that this has not been proved. “Even though we don’t think there is enough circulation to the brain for any function with NRP, we don’t know that with 100% certainty,” he said. “In my view, if there is a possibility of even the smallest amount of brain flow, we are going against the dead donor rule. We are rewriting the rules of death.”

Dr. Moazami countered: “Nothing in life is 100%, particularly in medicine. With that argument can you also prove with 100% certainty to me that there is absolutely no brain function with regular direct procurement DCD?  We know that brain death has started, but the question is: Has it been completed? We don’t know the answer to this question with 100% certainty, but that is the case for regular direct procurement DCD as well, and that has been accepted by almost everyone.

“The whole issue revolves around when are we comfortable that death has occurred,” he said. “Those against NRP are concerned that organs are being taken before the patient is dead. But the key point is that the patient has already been declared dead.”

Since there is some concern over the ethics of NRP, why not just stick to DCD with direct procurement?

Dr. Moazami argued that NRP results in healthier organs. “NRP allows more successful heart transplants, liver transplants, lung transplants. It preserves all the organs better,” he said. “This will have a big impact on recipients – they would obviously much prefer a healthier organ. In addition, the process is easier and cheaper, so more centers will be able to do it, therefore more transplants will get done and more lives will be saved if NRP is used.”

He added: “I am a physician taking care of sick patients. I believe I have to respect the wishes of the donor and the donor family; make sure I’m not doing any harm to the donor; and ensure the best quality possible of the organ I am retrieving to best serve the recipient. I am happy I am doing this by using NRP for DCD heart transplantation.”

But Dr. Peled argued that while NRP may have some possible advantages over direct procurement, that does not justify allowing a process to go ahead that is unethical.

“The fact that NRP may result in some benefits doesn’t justify violating the dead donor rule or the possibility, however small, of causing pain to the donor. If it’s unethical, it’s unethical. Full stop,” he said.

“I feel that NRP is not respecting the rights of our patients and that the process does not have adequate transparency. We took it to our local ethics committee, and they decided not to approve NRP in our health care system. I agree with this decision,” Dr. Peled said.  

“The trouble is different experts and different countries are not in agreement about this,” he added. “Reasonable, well-informed people are in disagreement. I do not believe we can have a standard of care where there is not consensus.”
 

Cautious nod

In a 2022 consensus statement, the International Society for Heart and Lung Transplantation (ISHLT) gave a cautious nod toward DCD and NRP, dependent on local recommendations.

The ISHLT conclusion reads: “With appropriate consideration of the ethical principles involved in organ donation, DCD can be undertaken in a morally permissible manner. In all cases, the introduction of DCD programs should be in accordance with local legal regulations. Countries lacking a DCD pathway should be encouraged to develop national ethical, professional, and legal frameworks to address both public and professional concerns.”

The author of a recent editorial on the subject, Ulrich P. Jorde, MD, head of the heart transplant program at Montefiore Medical Center, New York, said, “DCD is a great step forward. People regularly die on the heart transplant waiting list. DCD will increase the supply of donor hearts by 20% to 30%.”

However, he noted that while most societies have agreed on a protocol for organ donation based on brain death, the situation is more complicated with circulatory death.

“Different countries have different definitions of circulatory death. How long do we have to wait after the heart has stopped beating before the patient is declared dead? Most countries have agreed on 5 minutes, but other countries have imposed different periods and as such, different definitions of death.

“The ISHLT statement says that restarting the circulation is acceptable if death has been certified according to prevailing law and surgical interventions are undertaken to preclude any restoration of cerebral circulation. But our problem is that different regional societies have different definitions of circulatory, death which makes the situation confusing.”

Dr. Jorde added: “We also have to weigh the wishes of the donor and their family. If family, advocating what are presumed to be the donor’s wishes, have decided that DCD would be acceptable and they understand the concept and wish to donate the organs after circulatory death, this should be strongly considered under the concept of self-determination, a basic human right.”
 

Variations in practice around the world 

This ethical debate has led to large variations in practice around the world, with some countries, such as Spain, allowing both methods of DCD, while Australia allows direct procurement but not NRP, and Germany currently does not allow DCD at all.

In the United States, things are even more complicated, with some states allowing NRP while others don’t. Even within states, some hospitals and transplant organizations allow NRP, and others don’t. 

David A. D’Alessandro, MD, cardiac surgeon at Massachusetts General Hospital, Boston, uses only the direct procurement approach as his region does not allow NRP.

“The direct procurement approach is not controversial and to me that’s a big advantage. I believe we need to agree on the ethics first, and then get into a debate about which technique is better,” he told this news organization.

Dr. D’Alessandro and his group recently published the results of their study, with direct procurement DCD heart transplantation showing similar short-term clinical outcomes to DBD.

“We are only doing direct procurement and we are seeing good results that appear to be comparable to DBD. That is good enough for me,” he said.

Dr. D’Alessandro estimates that in the United States both types of DCD procedures are currently being done about equally.

“Anything we can do to increase the amount of hearts available for transplantation is a big deal,” he said. “At the moment, only the very sickest patients get a heart transplant, and many patients die on the transplant waiting list. Very sadly, many young people die every year from a circulatory death after having life support withdrawn. Before DCD, these beautiful functional organs were not able to be used. Now we have a way of saving lives with these organs.”

Dr. D’Alessandro noted that more and more centers in the United States are starting to perform DCD heart transplants. 

“Not every transplant center may join in as the DCD procedures are very resource-intensive and time-consuming. For low-volume transplant centers, it may not be worth the expense and anguish to do DCD heart transplants. But bigger centers will need to engage in DCD to remain competitive. My guess is that 50%-70% of U.S. transplant centers will do DCD in future.”

He said he thinks it is a “medical shortcoming” that agreement cannot be reached on the ethics of NRP. “In an ideal world everyone would be on the same page. It makes me a bit uncomfortable that some people think it’s okay and some people don’t.”

Adam DeVore, MD, a cardiologist at Duke University Medical Center, Durham, N.C., the first U.S. center to perform an adult DCD heart transplant, reported that his institution uses both methods, with the choice sometimes depending on how far the heart must travel.

“If the recipient is near, NRP may be chosen as the heart is transported on ice, but if it needs to go further away we are more likely to choose direct procurement and use of the OCS box,” he said. 

“I am really proud of what we’ve been able to do, helping to introduce DCD in the U.S.,” Dr. DeVore said. “This is having a massive benefit in increasing the number of hearts for donation with great outcomes.”  

But he acknowledged that the whole concept of DCD is somewhat controversial.  

“The idea of brain death really came about for the purpose of heart donation. The two things are very intricately tied. Trying to do heart donation without brain death having been declared is foreign to people. Also, in DCD there is the issue of [this]: When life support is removed, how long do we wait before death can be declared? That could be in conflict with how long the organ needs to remain viable. We are going through the process now of looking at these questions. There is a lot of variation in the U.S. about the withdrawal of care and the declaration of death, which is not completely standardized.

“But the concept of circulatory death itself is accepted after the withdrawal of life support. I think it’s the rush to take the organs out that makes it more difficult.”

Dr. DeVore said the field is moving forward now. “As the process has become more common, people have become more comfortable, probably because of the big difference it will make to saving lives. But we do need to try and standardize best practices.”

A recent Canadian review of the ethics of DCD concluded that the direct procurement approach would be in alignment with current medical guidelines, but that further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.

In the United Kingdom, the definition of death is brain-based, and brain death is defined on a neurological basis.

Dr. Stephen Large from Papworth explained that this recognizes the presence of brain-stem death through brain stem reflex testing after the withdrawal of life support, cardiorespiratory arrest and 5 further minutes of ischemia. As long as NRP does not restore intracranial (brainstem) perfusion after death has been confirmed, then it is consistent with laws for death determination and therefore both direct procurement and NRP are permissible.

However, the question over possible collateral flow to the brain has led the United Kingdom to pause the NRP technique as routine practice while this is investigated further. So, at the present time, the vast majority of DCD heart transplants are being conducted using the direct procurement approach.

But the United Kingdom is facing the bigger challenge: national funding that will soon end. “The DCD program in the U.K. has been extremely successful, increasing heart transplant rates by up to 28%,” Dr. Berman said. “Everybody wants it to continue. But at present the DCD program only has national funding in the U.K. until March 2023. We don’t know what will happen after that.”

The current model in the United Kingdom consists of three specialized DCD heart retrieval teams, a national protocol of direct organ procurement and delivery of DCD hearts to all seven transplant programs, both adult and pediatric.

If the national funding is not extended, “we will go back to individual hospitals trying to fund their own programs. That will be a serious threat to the program and could result in a large reduction in heart transplants,” said Dr. Berman.
 

Definition of death  

The crux of the issue with regard to NRP seems to be variations in how death is defined and the interpretation of those definitions.  

DCD donors will have had many tests indicating severe brain damage, a neurologist will have declared the prognosis is futile, and relatives will have agreed to withdraw life support, Dr. Jorde said. “The heart stops beating, and the stand-off time means that blood flow to the brain ceases completely for at least 5 minutes before circulatory death is declared. This is enough on its own to stop brain function.”

Dr. Large made the point that by the time the circulation is reestablished with NRP, more time has elapsed, and the brain will have been without perfusion for much longer than 5 minutes, so it would be “physiologically almost impossible” for there to be any blood flow to the brain.

“Because these brains are already very damaged before life support was removed, the intracranial pressure is high, which will further discourage blood flow to the brain,” he said. Then the donor goes through a period of anoxic heart arrest, up to 16 minutes at a minimum of no blood supply, enough on its own to stop meaningful brain function. 

“It’s asking an awful lot to believe that there might be any brain function left,” he said. “And if, on reestablishing the circulation with NRP, there is any blood in the collaterals, the pressure of such flow is so low it won’t enter the brain.”

Dr. Large also pointed out that the fact that the United Kingdom requires a neurologic definition for brain-stem death makes the process easier. 

In Australia, St. Vincent’s cardiologist Dr. MacDonald noted that death is defined as the irreversible cessation of circulation, so the NRP procedure is not allowed.

“With NRP, there is an ethical dilemma over whether the patient has legally died or not. Different countries have different ways of defining death. Perhaps society will have to review of the definition of death,” he suggested. Death is a process, “but for organ donation, we have to choose a moment in time of that process that satisfies everyone – when there is no prospect of recovery of the donor but the organs can still be utilized without harming the donor.” 

Dr. MacDonald said the field is in transition. “I don’t want to argue that one technique is better than the other; I think it’s good to have access to both techniques. Anything that will increase the number of transplants we can do is a good thing.”
 

Collaborative decision

Everyone seems to agree that there should be an effort to try to define death in a uniform way worldwide, and that international, national and local regulations are aligned with each other.

Dr. Jorde said: “It is of critical importance that local guidelines are streamlined, firstly in any one given country and then globally, and these things must be discussed transparently within society with all stakeholders – doctors, patients, citizens.”

Dr. Peled, from Providence St. Jude in California, concurred: “There is the possibility that we could change the definition of death, but that cannot be a decision based solely on transplant organizations. It has to be a collaborative decision with a large input from groups who do not have an interest in the procurement of organs.”

He added: “The dialogue so far has been civil, and everybody is trying to do the right thing. My hope is that as a civilized society we will figure out a way forward. At present, there is significant controversy about NRP, and families need to know that. My main concern is that if there is any lack of transparency in getting informed consent, then this risks people losing trust in the donation system.” 

Dr. Moazami, from NYU Langone, said the controversy has cast a cloud over the practice of NRP throughout the world. “We need to get it sorted out.”

He said he believes the way forward is to settle the question of whether there is any meaningful blood flow to the brain with the NRP technique.

“This is where the research has to focus. I believe this concern is hypothetical, but I am happy to do the studies to confirm that. Then, the issue should come to a rest. I think that is the right way forward – to do the studies rather than enforcing a moratorium on the practice because of a hypothetical concern.”

These studies on blood flow to the brain are now getting started in both the United Kingdom and the United States.

The U.K. study is being run by Antonio Rubino, MD, consultant in cardiothoracic anesthesia and intensive care at Papworth Hospital NHS Foundation and clinical lead, organ donation. Dr. Rubino explained that the study will assess cerebral blood flow using CT angiography of the brain. “We hypothesize that this will provide evidence to indicate that brain blood flow is not present during NRP and promote trust in the use of NRP in routine practice,” he said.

Dr. Large said: “Rather than having these tortured arguments, we will do the measurements. For the sake of society in this situation, I think it’s good to stop and take a breath. We must measure this, and we are doing just that.”

If there is any blood flow at all, Dr. Large said they will then have to seek expert guidance. “Say we find there is 50 mL of blood flow and normal blood flow is 1,500 mL/min. We will need expert guidance on whether it is remotely possible to be sentient on that. I would say it would be extraordinarily unlikely.”  

Dr. Berman summarized the situation: “DCD is increasing the availability of hearts for transplant. This is saving lives, reducing the number of patients on the waiting list, and reducing hospital stays for patients unable to leave the hospital without a transplant. It is definitely here to stay. It is crucial that it gets funded properly, and it is also crucial that we resolve the NRP ethical issues as soon as possible.”

He is hopeful that some of these issues will be resolved this year.

Dr. MacDonald reported he has received “in-kind” support from Transmedics through provision of research modules for preclinical research studies. Dr. D’Alessandro reported he is on the speakers bureau for Abiomed, not relevant to this article. No other relevant disclosures were reported.
 

A version of this article first appeared on Medscape.com.

NEW ORLEANS – Treatment of patients with heart failure with preserved ejection fraction (HFpEF) with the SGLT2 inhibitor dapagliflozin (Farxiga) for 24 weeks produced significant and beneficial reductions in left-heart filling pressures in a mechanistic, randomized clinical study.

The findings “provide new insight into the mechanisms underlying the favorable clinical effects of dapagliflozin in patients with HFpEF,” Barry A. Borlaug, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. “Elevations in left heart filling pressures at rest and during exercise are fundamental pathophysiologic features of HFpEF,” he noted.

Results from prior studies documented the benefit of dapagliflozin for improving clinical outcomes in patients with HFpEF in the DELIVER trial, and for the related sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (Jardiance) in the EMPEROR-Preserved trial. The new findings presented by Dr. Borlaug provide evidence from a placebo-controlled, prospective study for one way by which these SGLT2 inhibitors exert this benefit in patients with HFpEF.

The results of his single-center study showed that, in patients with HFpEF who also exhibited “severe” elevations in pulmonary capillary wedge pressure (PCWP) during exercise, 24 weeks of treatment with dapagliflozin led to a significant reduction in PCWP during exercise. The treatment produced an average 6.1–mm Hg drop from baseline compared with control patients who received placebo. A similar pattern occurred when these patients were at rest, when dapagliflozin treatment linked with a significant average reduction in PCWP from baseline of 3.5 mm Hg compared with controls.
 

Improving a ‘specific and fundamental’ feature of HFpEF

“This fantastic study looked at one of the fundamental aspects of HFpEF,” said John R. Teerlink, MD, designated discussant for the study. “You’ve shown that dapagliflozin targets a specific and fundamental” manifestation of HFpEF by lowering PCWP, said Dr. Teerlink, director of Heart Failure at the San Francisco Veterans Affairs Medical Center.

However, Dr. Teerlink added, the study did not directly address the related question of what physiologic action of dapagliflozin produces this notable drop in PCWP.

“We’re just starting to look at that,” replied Dr. Borlaug, a cardiologist and professor at the Mayo Clinic in Rochester, Minn.

He reported finding an intriguing correlate in the current study linked to the cut in PCWP with dapagliflozin treatment. The SGLT2 inhibitor at a standard daily 10-mg dose produced an average 3.5-kg drop in body weight in the dapagliflozin-treated patients that significantly linked with the changes in PCWP both at rest and during exercise. Dapagliflozin-treated patients also showed a significant reduction from their baseline plasma volume compared with placebo-treated patients, but this “poorly correlated” with the dapagliflozin-linked cuts in PCWP, Dr. Borlaug said.

“I don’t think this means weight loss is the cause of the hemodynamic benefit, but maybe it’s an indicator. When patients [with HFpEF] lose weight, they are in a metabolic state that leads to good changes in hemodynamics,” he suggested. “My guess is that there is probably a combination of many different little things [caused by dapagliflozin treatment of patients with HFpEF] that together result in the 20%-25% relative improvement we see in filling pressure.”
 

An ‘obese, cardiometabolic’ HFpEF phenotype

The study enrolled patients with HFpEF and a left ventricular ejection fraction of at least 50%, a New York Heart Association functional class of 2 or 3, and a PCWP during exercise of at least 25 mm Hg. Of the 37 evaluable patients, about two-thirds of the patients were women, more than two-thirds were in functional class 3, about 70% were obese, and their average ejection fraction was about 62%. The study excluded patients with HFpEF who also had type 1 diabetes, cardiomyopathy, pericardial disease, or other causes of dyspnea or heart failure.

Dr. Teerlink asked about the generalizability of the findings, as the study cohort seemed to differ in certain respects from the patients enrolled in the DELIVER trial, and because of the many apparently distinct patient phenotypes that exist within the scope of HFpEF.

An “obese, cardiometabolic phenotype” predominated the study cohort, Dr. Borlaug said. “The patients we enrolled look like the HFpEF patients seen in U.S. clinics.” However, he added that “in reality, many [HFpEF phenotypes] coexist in one patient. It’s not that simple,” that every patient with HFpEF can be categorized into a single HFpEF phenotype.

The researchers monitored PCWP invasively with high-fidelity micromanometer catheters.

The study was sponsored by AstraZeneca, the company that markets dapagliflozin (Farxiga). Dr. Borlaug has received research funding from AstraZeneca, as well as from Corvia, GlaxoSmithKline, Medtronic, Mesoblast, Novo Nordisk, and Tenax. Dr. Teerlink has had financial relationships with AstraZeneca, as well as with Amgen, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Cytokinetics, Medtronic, Merck, Novartis, Servier, and Windtree Therapeutics.

NEW ORLEANS – Treatment of patients with heart failure with preserved ejection fraction (HFpEF) with the SGLT2 inhibitor dapagliflozin (Farxiga) for 24 weeks produced significant and beneficial reductions in left-heart filling pressures in a mechanistic, randomized clinical study.

The findings “provide new insight into the mechanisms underlying the favorable clinical effects of dapagliflozin in patients with HFpEF,” Barry A. Borlaug, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. “Elevations in left heart filling pressures at rest and during exercise are fundamental pathophysiologic features of HFpEF,” he noted.

Results from prior studies documented the benefit of dapagliflozin for improving clinical outcomes in patients with HFpEF in the DELIVER trial, and for the related sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (Jardiance) in the EMPEROR-Preserved trial. The new findings presented by Dr. Borlaug provide evidence from a placebo-controlled, prospective study for one way by which these SGLT2 inhibitors exert this benefit in patients with HFpEF.

The results of his single-center study showed that, in patients with HFpEF who also exhibited “severe” elevations in pulmonary capillary wedge pressure (PCWP) during exercise, 24 weeks of treatment with dapagliflozin led to a significant reduction in PCWP during exercise. The treatment produced an average 6.1–mm Hg drop from baseline compared with control patients who received placebo. A similar pattern occurred when these patients were at rest, when dapagliflozin treatment linked with a significant average reduction in PCWP from baseline of 3.5 mm Hg compared with controls.
 

Improving a ‘specific and fundamental’ feature of HFpEF

“This fantastic study looked at one of the fundamental aspects of HFpEF,” said John R. Teerlink, MD, designated discussant for the study. “You’ve shown that dapagliflozin targets a specific and fundamental” manifestation of HFpEF by lowering PCWP, said Dr. Teerlink, director of Heart Failure at the San Francisco Veterans Affairs Medical Center.

However, Dr. Teerlink added, the study did not directly address the related question of what physiologic action of dapagliflozin produces this notable drop in PCWP.

“We’re just starting to look at that,” replied Dr. Borlaug, a cardiologist and professor at the Mayo Clinic in Rochester, Minn.

He reported finding an intriguing correlate in the current study linked to the cut in PCWP with dapagliflozin treatment. The SGLT2 inhibitor at a standard daily 10-mg dose produced an average 3.5-kg drop in body weight in the dapagliflozin-treated patients that significantly linked with the changes in PCWP both at rest and during exercise. Dapagliflozin-treated patients also showed a significant reduction from their baseline plasma volume compared with placebo-treated patients, but this “poorly correlated” with the dapagliflozin-linked cuts in PCWP, Dr. Borlaug said.

“I don’t think this means weight loss is the cause of the hemodynamic benefit, but maybe it’s an indicator. When patients [with HFpEF] lose weight, they are in a metabolic state that leads to good changes in hemodynamics,” he suggested. “My guess is that there is probably a combination of many different little things [caused by dapagliflozin treatment of patients with HFpEF] that together result in the 20%-25% relative improvement we see in filling pressure.”
 

An ‘obese, cardiometabolic’ HFpEF phenotype

The study enrolled patients with HFpEF and a left ventricular ejection fraction of at least 50%, a New York Heart Association functional class of 2 or 3, and a PCWP during exercise of at least 25 mm Hg. Of the 37 evaluable patients, about two-thirds of the patients were women, more than two-thirds were in functional class 3, about 70% were obese, and their average ejection fraction was about 62%. The study excluded patients with HFpEF who also had type 1 diabetes, cardiomyopathy, pericardial disease, or other causes of dyspnea or heart failure.

Dr. Teerlink asked about the generalizability of the findings, as the study cohort seemed to differ in certain respects from the patients enrolled in the DELIVER trial, and because of the many apparently distinct patient phenotypes that exist within the scope of HFpEF.

An “obese, cardiometabolic phenotype” predominated the study cohort, Dr. Borlaug said. “The patients we enrolled look like the HFpEF patients seen in U.S. clinics.” However, he added that “in reality, many [HFpEF phenotypes] coexist in one patient. It’s not that simple,” that every patient with HFpEF can be categorized into a single HFpEF phenotype.

The researchers monitored PCWP invasively with high-fidelity micromanometer catheters.

The study was sponsored by AstraZeneca, the company that markets dapagliflozin (Farxiga). Dr. Borlaug has received research funding from AstraZeneca, as well as from Corvia, GlaxoSmithKline, Medtronic, Mesoblast, Novo Nordisk, and Tenax. Dr. Teerlink has had financial relationships with AstraZeneca, as well as with Amgen, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Cytokinetics, Medtronic, Merck, Novartis, Servier, and Windtree Therapeutics.

NEW ORLEANS – Treatment of patients with heart failure with preserved ejection fraction (HFpEF) with the SGLT2 inhibitor dapagliflozin (Farxiga) for 24 weeks produced significant and beneficial reductions in left-heart filling pressures in a mechanistic, randomized clinical study.

The findings “provide new insight into the mechanisms underlying the favorable clinical effects of dapagliflozin in patients with HFpEF,” Barry A. Borlaug, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. “Elevations in left heart filling pressures at rest and during exercise are fundamental pathophysiologic features of HFpEF,” he noted.

Results from prior studies documented the benefit of dapagliflozin for improving clinical outcomes in patients with HFpEF in the DELIVER trial, and for the related sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (Jardiance) in the EMPEROR-Preserved trial. The new findings presented by Dr. Borlaug provide evidence from a placebo-controlled, prospective study for one way by which these SGLT2 inhibitors exert this benefit in patients with HFpEF.

The results of his single-center study showed that, in patients with HFpEF who also exhibited “severe” elevations in pulmonary capillary wedge pressure (PCWP) during exercise, 24 weeks of treatment with dapagliflozin led to a significant reduction in PCWP during exercise. The treatment produced an average 6.1–mm Hg drop from baseline compared with control patients who received placebo. A similar pattern occurred when these patients were at rest, when dapagliflozin treatment linked with a significant average reduction in PCWP from baseline of 3.5 mm Hg compared with controls.
 

Improving a ‘specific and fundamental’ feature of HFpEF

“This fantastic study looked at one of the fundamental aspects of HFpEF,” said John R. Teerlink, MD, designated discussant for the study. “You’ve shown that dapagliflozin targets a specific and fundamental” manifestation of HFpEF by lowering PCWP, said Dr. Teerlink, director of Heart Failure at the San Francisco Veterans Affairs Medical Center.

However, Dr. Teerlink added, the study did not directly address the related question of what physiologic action of dapagliflozin produces this notable drop in PCWP.

“We’re just starting to look at that,” replied Dr. Borlaug, a cardiologist and professor at the Mayo Clinic in Rochester, Minn.

He reported finding an intriguing correlate in the current study linked to the cut in PCWP with dapagliflozin treatment. The SGLT2 inhibitor at a standard daily 10-mg dose produced an average 3.5-kg drop in body weight in the dapagliflozin-treated patients that significantly linked with the changes in PCWP both at rest and during exercise. Dapagliflozin-treated patients also showed a significant reduction from their baseline plasma volume compared with placebo-treated patients, but this “poorly correlated” with the dapagliflozin-linked cuts in PCWP, Dr. Borlaug said.

“I don’t think this means weight loss is the cause of the hemodynamic benefit, but maybe it’s an indicator. When patients [with HFpEF] lose weight, they are in a metabolic state that leads to good changes in hemodynamics,” he suggested. “My guess is that there is probably a combination of many different little things [caused by dapagliflozin treatment of patients with HFpEF] that together result in the 20%-25% relative improvement we see in filling pressure.”
 

An ‘obese, cardiometabolic’ HFpEF phenotype

The study enrolled patients with HFpEF and a left ventricular ejection fraction of at least 50%, a New York Heart Association functional class of 2 or 3, and a PCWP during exercise of at least 25 mm Hg. Of the 37 evaluable patients, about two-thirds of the patients were women, more than two-thirds were in functional class 3, about 70% were obese, and their average ejection fraction was about 62%. The study excluded patients with HFpEF who also had type 1 diabetes, cardiomyopathy, pericardial disease, or other causes of dyspnea or heart failure.

Dr. Teerlink asked about the generalizability of the findings, as the study cohort seemed to differ in certain respects from the patients enrolled in the DELIVER trial, and because of the many apparently distinct patient phenotypes that exist within the scope of HFpEF.

An “obese, cardiometabolic phenotype” predominated the study cohort, Dr. Borlaug said. “The patients we enrolled look like the HFpEF patients seen in U.S. clinics.” However, he added that “in reality, many [HFpEF phenotypes] coexist in one patient. It’s not that simple,” that every patient with HFpEF can be categorized into a single HFpEF phenotype.

The researchers monitored PCWP invasively with high-fidelity micromanometer catheters.

The study was sponsored by AstraZeneca, the company that markets dapagliflozin (Farxiga). Dr. Borlaug has received research funding from AstraZeneca, as well as from Corvia, GlaxoSmithKline, Medtronic, Mesoblast, Novo Nordisk, and Tenax. Dr. Teerlink has had financial relationships with AstraZeneca, as well as with Amgen, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Cytokinetics, Medtronic, Merck, Novartis, Servier, and Windtree Therapeutics.

The Mediterranean diet appears to be associated with a lower incidence of cardiovascular disease (CVD) and mortality in women, new observational data suggest.

Those who had a higher adherence to a Mediterranean diet had a 24% lower risk for cardiovascular disease and 23% lower risk for death.

“A healthy diet is a huge factor in preventing heart disease. However, current guidelines on preventing heart disease lack sex-specific recommendations,” said senior author Sarah Zaman, MBBS, PhD, an associate professor of medicine and principal research fellow at the University of Sydney’s Westmead Applied Research Centre.

snyferok/Thinkstock

Analyzing cardiovascular outcomes

Dr. Zaman and colleagues conducted a systematic review and meta-analysis of 16 studies published between 2006 and 2021 that reported a Mediterranean diet score and included either all women or had stratified outcomes by sex. They excluded studies that referred to only certain components of the Mediterranean diet or combined it with other lifestyle-related factors.

The studies, which were mainly conducted in the United States and Europe, included 722,495 adult women without previous clinical or subclinical CVD, with a median follow-up of 12.5 years.

Higher Mediterranean diet adherence was defined as the highest category reporting the highest range of Mediterranean diet scores, and lower adherence was defined as the lowest category reporting lowest scores. Incident CVD included coronary heart disease, myocardial infarction, stroke, heart failure, cardiovascular death, major adverse cardiovascular events, major adverse cardiac cerebrovascular events, and patient-reported CVD.

Overall, higher adherence to a Mediterranean diet was associated with lower CVD incidence (hazard ratio, 0.76; 95% confidence interval, 0.72-0.81), total mortality (HR, 0.77; 95% CI, 0.74-0.80), and coronary heart disease (HR, 0.75; 95% CI, 0.65-0.87).

Stroke incidence was also lower among women who adhered to the Mediterranean diet, although it wasn’t considered statistically significant (HR, 0.87; 95% CI, 0.76-1.01).

Additional analyses found similar reductions in risk across women of different ethnicities. Higher Mediterranean diet adherence was associated with lower CVD incidence for both women of European descent (HR, 0.76; 95% CI, 0.59-0.98) and women of non-European descent – Asian, Native Hawaiian, and African American – (HR, 0.79; 95% CI, 0.72-0.87).

The results didn’t materially change in sensitivity analyses, the authors note. Excluding one study at a time, the pooled HRs for the highest versus the lowest Mediterranean diet adherence ranged from 0.76 (95% CI, 0.72-0.80) to 0.83 (95% CI, 0.70-0.98) for incident CVD and from 0.77 (95% CI, 0.75-0.80) to 0.77 (95% CI, 0.74-0.81) for total mortality among women.

At the same time, the authors pointed to several limitations, including the observational nature of all of the studies, the reliance on self-reported food frequency questionnaires, and heterogeneity in the adjustments for influential factors across the studies.
 

Additional considerations

Dr. Zaman and colleagues called for more sex-specific research in cardiology, including risk factors related to premature menopause, preeclampsia, gestational diabetes, and autoimmune diseases such as systemic lupus.

Future studies should also explore the underlying mechanisms that may explain the links between the Mediterranean diet, cardiovascular disease, and death, the authors write. For instance, the diet may reduce inflammation and cardiovascular risk factors through antioxidant and beneficial gut microbiome pathways. Other components of the diet – such as polyphenols, nitrates, omega-3 fatty acids, higher fiber intake, and reduced glycemic load – may also play a role.

“It was striking to see how strong the long-term cardioprotective properties of a Mediterranean-type dietary pattern were,” said Samia Mora, MD, MHS, a professor of medicine at Harvard Medical School and director of the Center for Lipid Metabolomics at Brigham and Women’s Hospital.

Dr. Mora, who wasn’t involved with this study, has researched potential mechanisms related to the Mediterranean diet, cardiovascular events, and diabetes in women. She and colleagues have found that women with high adherence to the diet are more likely to have lower inflammation, insulin resistance, body mass index, and blood pressure, as well as improved lipid and metabolic profiles.

“This could represent an opportunity to intervene earlier and more intensively on improving inflammation, insulin resistance, and cardiometabolic health through evidence-based dietary approaches such as the Mediterranean diet,” she said. “As health care providers, we should promote the healthy dietary attributes of the Mediterranean diet, especially as many of our patients in the U.S. are less familiar with the Mediterranean diet and how to incorporate its components into daily food intake.”

The study did not receive any funding. Dr. Zaman was supported by a Heart Foundation Future Leader Fellowship. The authors declared no conflicts of interest. Dr. Mora reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

The Mediterranean diet appears to be associated with a lower incidence of cardiovascular disease (CVD) and mortality in women, new observational data suggest.

Those who had a higher adherence to a Mediterranean diet had a 24% lower risk for cardiovascular disease and 23% lower risk for death.

“A healthy diet is a huge factor in preventing heart disease. However, current guidelines on preventing heart disease lack sex-specific recommendations,” said senior author Sarah Zaman, MBBS, PhD, an associate professor of medicine and principal research fellow at the University of Sydney’s Westmead Applied Research Centre.

snyferok/Thinkstock

Analyzing cardiovascular outcomes

Dr. Zaman and colleagues conducted a systematic review and meta-analysis of 16 studies published between 2006 and 2021 that reported a Mediterranean diet score and included either all women or had stratified outcomes by sex. They excluded studies that referred to only certain components of the Mediterranean diet or combined it with other lifestyle-related factors.

The studies, which were mainly conducted in the United States and Europe, included 722,495 adult women without previous clinical or subclinical CVD, with a median follow-up of 12.5 years.

Higher Mediterranean diet adherence was defined as the highest category reporting the highest range of Mediterranean diet scores, and lower adherence was defined as the lowest category reporting lowest scores. Incident CVD included coronary heart disease, myocardial infarction, stroke, heart failure, cardiovascular death, major adverse cardiovascular events, major adverse cardiac cerebrovascular events, and patient-reported CVD.

Overall, higher adherence to a Mediterranean diet was associated with lower CVD incidence (hazard ratio, 0.76; 95% confidence interval, 0.72-0.81), total mortality (HR, 0.77; 95% CI, 0.74-0.80), and coronary heart disease (HR, 0.75; 95% CI, 0.65-0.87).

Stroke incidence was also lower among women who adhered to the Mediterranean diet, although it wasn’t considered statistically significant (HR, 0.87; 95% CI, 0.76-1.01).

Additional analyses found similar reductions in risk across women of different ethnicities. Higher Mediterranean diet adherence was associated with lower CVD incidence for both women of European descent (HR, 0.76; 95% CI, 0.59-0.98) and women of non-European descent – Asian, Native Hawaiian, and African American – (HR, 0.79; 95% CI, 0.72-0.87).

The results didn’t materially change in sensitivity analyses, the authors note. Excluding one study at a time, the pooled HRs for the highest versus the lowest Mediterranean diet adherence ranged from 0.76 (95% CI, 0.72-0.80) to 0.83 (95% CI, 0.70-0.98) for incident CVD and from 0.77 (95% CI, 0.75-0.80) to 0.77 (95% CI, 0.74-0.81) for total mortality among women.

At the same time, the authors pointed to several limitations, including the observational nature of all of the studies, the reliance on self-reported food frequency questionnaires, and heterogeneity in the adjustments for influential factors across the studies.
 

Additional considerations

Dr. Zaman and colleagues called for more sex-specific research in cardiology, including risk factors related to premature menopause, preeclampsia, gestational diabetes, and autoimmune diseases such as systemic lupus.

Future studies should also explore the underlying mechanisms that may explain the links between the Mediterranean diet, cardiovascular disease, and death, the authors write. For instance, the diet may reduce inflammation and cardiovascular risk factors through antioxidant and beneficial gut microbiome pathways. Other components of the diet – such as polyphenols, nitrates, omega-3 fatty acids, higher fiber intake, and reduced glycemic load – may also play a role.

“It was striking to see how strong the long-term cardioprotective properties of a Mediterranean-type dietary pattern were,” said Samia Mora, MD, MHS, a professor of medicine at Harvard Medical School and director of the Center for Lipid Metabolomics at Brigham and Women’s Hospital.

Dr. Mora, who wasn’t involved with this study, has researched potential mechanisms related to the Mediterranean diet, cardiovascular events, and diabetes in women. She and colleagues have found that women with high adherence to the diet are more likely to have lower inflammation, insulin resistance, body mass index, and blood pressure, as well as improved lipid and metabolic profiles.

“This could represent an opportunity to intervene earlier and more intensively on improving inflammation, insulin resistance, and cardiometabolic health through evidence-based dietary approaches such as the Mediterranean diet,” she said. “As health care providers, we should promote the healthy dietary attributes of the Mediterranean diet, especially as many of our patients in the U.S. are less familiar with the Mediterranean diet and how to incorporate its components into daily food intake.”

The study did not receive any funding. Dr. Zaman was supported by a Heart Foundation Future Leader Fellowship. The authors declared no conflicts of interest. Dr. Mora reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

The Mediterranean diet appears to be associated with a lower incidence of cardiovascular disease (CVD) and mortality in women, new observational data suggest.

Those who had a higher adherence to a Mediterranean diet had a 24% lower risk for cardiovascular disease and 23% lower risk for death.

“A healthy diet is a huge factor in preventing heart disease. However, current guidelines on preventing heart disease lack sex-specific recommendations,” said senior author Sarah Zaman, MBBS, PhD, an associate professor of medicine and principal research fellow at the University of Sydney’s Westmead Applied Research Centre.

snyferok/Thinkstock

Analyzing cardiovascular outcomes

Dr. Zaman and colleagues conducted a systematic review and meta-analysis of 16 studies published between 2006 and 2021 that reported a Mediterranean diet score and included either all women or had stratified outcomes by sex. They excluded studies that referred to only certain components of the Mediterranean diet or combined it with other lifestyle-related factors.

The studies, which were mainly conducted in the United States and Europe, included 722,495 adult women without previous clinical or subclinical CVD, with a median follow-up of 12.5 years.

Higher Mediterranean diet adherence was defined as the highest category reporting the highest range of Mediterranean diet scores, and lower adherence was defined as the lowest category reporting lowest scores. Incident CVD included coronary heart disease, myocardial infarction, stroke, heart failure, cardiovascular death, major adverse cardiovascular events, major adverse cardiac cerebrovascular events, and patient-reported CVD.

Overall, higher adherence to a Mediterranean diet was associated with lower CVD incidence (hazard ratio, 0.76; 95% confidence interval, 0.72-0.81), total mortality (HR, 0.77; 95% CI, 0.74-0.80), and coronary heart disease (HR, 0.75; 95% CI, 0.65-0.87).

Stroke incidence was also lower among women who adhered to the Mediterranean diet, although it wasn’t considered statistically significant (HR, 0.87; 95% CI, 0.76-1.01).

Additional analyses found similar reductions in risk across women of different ethnicities. Higher Mediterranean diet adherence was associated with lower CVD incidence for both women of European descent (HR, 0.76; 95% CI, 0.59-0.98) and women of non-European descent – Asian, Native Hawaiian, and African American – (HR, 0.79; 95% CI, 0.72-0.87).

The results didn’t materially change in sensitivity analyses, the authors note. Excluding one study at a time, the pooled HRs for the highest versus the lowest Mediterranean diet adherence ranged from 0.76 (95% CI, 0.72-0.80) to 0.83 (95% CI, 0.70-0.98) for incident CVD and from 0.77 (95% CI, 0.75-0.80) to 0.77 (95% CI, 0.74-0.81) for total mortality among women.

At the same time, the authors pointed to several limitations, including the observational nature of all of the studies, the reliance on self-reported food frequency questionnaires, and heterogeneity in the adjustments for influential factors across the studies.
 

Additional considerations

Dr. Zaman and colleagues called for more sex-specific research in cardiology, including risk factors related to premature menopause, preeclampsia, gestational diabetes, and autoimmune diseases such as systemic lupus.

Future studies should also explore the underlying mechanisms that may explain the links between the Mediterranean diet, cardiovascular disease, and death, the authors write. For instance, the diet may reduce inflammation and cardiovascular risk factors through antioxidant and beneficial gut microbiome pathways. Other components of the diet – such as polyphenols, nitrates, omega-3 fatty acids, higher fiber intake, and reduced glycemic load – may also play a role.

“It was striking to see how strong the long-term cardioprotective properties of a Mediterranean-type dietary pattern were,” said Samia Mora, MD, MHS, a professor of medicine at Harvard Medical School and director of the Center for Lipid Metabolomics at Brigham and Women’s Hospital.

Dr. Mora, who wasn’t involved with this study, has researched potential mechanisms related to the Mediterranean diet, cardiovascular events, and diabetes in women. She and colleagues have found that women with high adherence to the diet are more likely to have lower inflammation, insulin resistance, body mass index, and blood pressure, as well as improved lipid and metabolic profiles.

“This could represent an opportunity to intervene earlier and more intensively on improving inflammation, insulin resistance, and cardiometabolic health through evidence-based dietary approaches such as the Mediterranean diet,” she said. “As health care providers, we should promote the healthy dietary attributes of the Mediterranean diet, especially as many of our patients in the U.S. are less familiar with the Mediterranean diet and how to incorporate its components into daily food intake.”

The study did not receive any funding. Dr. Zaman was supported by a Heart Foundation Future Leader Fellowship. The authors declared no conflicts of interest. Dr. Mora reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Datascope/Getinge is recalling certain Cardiosave Hybrid and Cardiosave Rescue Intra-Aortic Balloon Pumps (IABPs) because the coiled cable connecting the display and base on some units may fail, causing an unexpected shutdown without warnings or alarms to alert the user.

The U.S. Food and Drug Administration has identified this as a class I recall, the most serious type of recall, because of the risk for serious injury or death.

The FDA warns that an unexpected pump shutdown and any interruption to therapy that occurs can lead to hemodynamic instability, organ damage, and/or death, especially in patients who are critically ill and most likely to receive therapy using these devices.

Wikimedia Commons/FitzColinGerald/Creative Commons License

A version of this article first appeared on Medscape.com.

Datascope/Getinge is recalling certain Cardiosave Hybrid and Cardiosave Rescue Intra-Aortic Balloon Pumps (IABPs) because the coiled cable connecting the display and base on some units may fail, causing an unexpected shutdown without warnings or alarms to alert the user.

The U.S. Food and Drug Administration has identified this as a class I recall, the most serious type of recall, because of the risk for serious injury or death.

The FDA warns that an unexpected pump shutdown and any interruption to therapy that occurs can lead to hemodynamic instability, organ damage, and/or death, especially in patients who are critically ill and most likely to receive therapy using these devices.

Wikimedia Commons/FitzColinGerald/Creative Commons License

A version of this article first appeared on Medscape.com.

Datascope/Getinge is recalling certain Cardiosave Hybrid and Cardiosave Rescue Intra-Aortic Balloon Pumps (IABPs) because the coiled cable connecting the display and base on some units may fail, causing an unexpected shutdown without warnings or alarms to alert the user.

The U.S. Food and Drug Administration has identified this as a class I recall, the most serious type of recall, because of the risk for serious injury or death.

The FDA warns that an unexpected pump shutdown and any interruption to therapy that occurs can lead to hemodynamic instability, organ damage, and/or death, especially in patients who are critically ill and most likely to receive therapy using these devices.

Wikimedia Commons/FitzColinGerald/Creative Commons License

A version of this article first appeared on Medscape.com.

NEW ORLEANS – An investigational, first-in class agent that delivers a completely new type of intervention to patients with pulmonary arterial hypertension (PAH) scored a clear win in the STELLAR trial, the first to complete among three phase 3 trials that are testing this agent.

Sotatercept, administered subcutaneously every 3 weeks for 24 weeks, improved from baseline average 6-minute walk distance (6MWD) by a significant and clinically meaningful 40.8 meters, compared with placebo, for the trial’s primary efficacy endpoint (P < .001). The treatment also “delivered broad clinical benefit across multiple domains including hemodynamics, World Health Organization functional class, disease biomarkers, risk scores and patient-reported outcomes,” Marius M. Hoeper, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Mitchel L. Zoler/MDedge News

“These results establish the clinical utility of sotatercept, administered in combination with approved PAH therapies, as a new treatment for PAH,” added Dr. Hoeper, professor and deputy director of the department of respiratory medicine at Hannover (Germany) Medical School,

“The most important aspect was the hemodynamic improvement,” with sotatercept treatment, which led to an average 235 dyn/sec per cm⁻⁵ reduction in pulmonary vascular resistance from baseline and an average cut in pulmonary artery pressure of 13.9 mm Hg from baseline, compared with placebo, a result that’s “unheard of,” Dr. Hoeper said in a press conference during the meeting.

“With other tested agents we usually see very little improvement in pulmonary artery pressure. This is a signal that we achieved some reversing of the pathological changes in the pulmonary vessels that lead to” PAH, he added.

Simultaneously with his report the findings also appeared online in the New England Journal of Medicine.
 

‘A new hope’ for patients with PAH

Based on the reported findings, sotatercept is a “very exciting boutique molecule” that will “offer patients with PAH a very exciting new treatment,” commented Rhonda Cooper-DeHoff, PharmD, a designated discussant and a researcher at the University of Florida, Gainesville.

Mitchel L. Zoler/MDedge News

“This study is a new hope for patients with PAH. Until now, they’ve had really bad outcomes, but [in this study] we see significant differences in 6MWD, hemodynamics, and risk factors. Overall, I think the benefit is greater than the risk” it may pose to patients through potential adverse effects, commented Julia Grapsa, MD, PhD, a cardiologist at St. Thomas Hospital in London, and another discussant at the meeting.

“The results are impressive” and “encouraging,” and “suggest that sotatercept may represent a new and clinically consequential addition to current medications for PAH,” wrote three clinicians from Canyons Region Intermountain Medical Center in Murray, Utah, in an editorial that accompanied the published report.

But the authors of the editorial also raised several cautions and concerns. They questioned the generalizability of the findings, noting that the patients with PAH enrolled in the study were all adults who were clinically stable and an average of more than 8 years out from their initial PAH diagnosis, and more than 90% were on stable treatment for PAH with two or three agents specific for treating the disorder. The study cohort also had a disproportionately high enrollment of patients with idiopathic (59%) or heritable (18%) forms of PAH, and the 15% of patients in the trial with connective tissue disease represented a disproportionately low prevalence of this PAH subtype.

The editorialists also called for “ongoing vigilance” for adverse effects from sotatercept treatment, although they acknowledged that the adverse effects reported to date from sotatercept are “largely reassuring.”
 

Death or clinical worsening cut by 84%

STELLAR randomized 323 patients at 91 sites in 21 countries with WHO Group 1 PAH and with WHO functional class II or III disease to receive either sotatercept or placebo for 24 weeks, with an option for treatment to continue beyond that until the last patient in the study reached 24 weeks on treatment, resulting in an overall median treatment duration of nearly 33 weeks.

In addition to the significant result for the primary endpoint, the 163 patients who received sotatercept had significant improvements, compared with 160 placebo-treated patients, for eight of nine secondary endpoints. The only secondary endpoint with a neutral result was for a measure of cognitive and emotional wellbeing, a parameter that was already at a normal level at baseline in most enrolled patients, Dr. Hoeper explained.

The incidence of either death or an event indicative of clinical worsening during the overall median follow-up of almost 33 weeks was 26.3% among the control patients and 5.5% among those who received sotatercept. This translated into a significant reduction for this endpoint of 84% with sotatercept treatment, compared with placebo.

The rates of treatment-emergent adverse events leading to discontinuation were roughly the same in the control and sotatercept arms, and the incidence of severe or serious treatment-emergent adverse events was higher among the control patients.

The most common adverse event on sotatercept was bleeding events, which occurred in 32% of those on sotatercept and in 16% of the control patients, but the events in the sotatercept arm were “mostly mild,” said Dr. Hoeper. The next most frequent adverse event during sotatercept treatment was appearance of telangiectasias, which occurred in 14% of those on sotatercept and in 4% of control patients.

“It’s an uncommon adverse event profile, but not unexpected for a drug with its mechanism of action,” he said.

Drug binds activin, a pathologic driver of PAH

Sotatercept is an engineered molecule that combines a section of a human immunoglobulin G molecule with a portion of the receptor for activin. This structure allows sotatercept to bind free activin molecules in a patient’s blood, thereby removing a key driver of the pulmonary vascular wall remodeling that is at the pathologic root of PAH.

“Hyperproliferation of blood vessel–wall cells” caused by activin signaling “is perhaps the most important driver of PAH,” Dr. Hoeper said. “Sotatercept allows us for the first time to target the underlying mechanism behind PAH.”

Still ongoing are the HYPERION and ZENITH phase 3 trials of sotatercept. HYPERION is enrolling patients with newly diagnosed or high-risk PAH and is expected to complete in 2028. ZENITH is enrolling patients with more advanced PAH and a higher mortality risk, with results expected in 2026.

Sotatercept has received “Breakthrough Therapy” designation and “Orphan Drug” designation by the Food and Drug Administration, and “Priority Medicines” designation and “Orphan Drug” designation by the European Medicines Agency for the treatment of PAH. One recent review estimated a worldwide PAH prevalence of about 3-4 cases/100,000, which for the United States translates into a total prevalence of perhaps 10,000-15,000 affected people.

STELLAR was funded by Acceleron Pharma, a subsidiary of Merck. Dr. Hoeper is a consultant to Acceleron. Dr. Cooper-DeHoff, Dr. Grapsa, and the authors of the editorial on STELLAR have no relevant disclosures.

NEW ORLEANS – An investigational, first-in class agent that delivers a completely new type of intervention to patients with pulmonary arterial hypertension (PAH) scored a clear win in the STELLAR trial, the first to complete among three phase 3 trials that are testing this agent.

Sotatercept, administered subcutaneously every 3 weeks for 24 weeks, improved from baseline average 6-minute walk distance (6MWD) by a significant and clinically meaningful 40.8 meters, compared with placebo, for the trial’s primary efficacy endpoint (P < .001). The treatment also “delivered broad clinical benefit across multiple domains including hemodynamics, World Health Organization functional class, disease biomarkers, risk scores and patient-reported outcomes,” Marius M. Hoeper, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Mitchel L. Zoler/MDedge News

“These results establish the clinical utility of sotatercept, administered in combination with approved PAH therapies, as a new treatment for PAH,” added Dr. Hoeper, professor and deputy director of the department of respiratory medicine at Hannover (Germany) Medical School,

“The most important aspect was the hemodynamic improvement,” with sotatercept treatment, which led to an average 235 dyn/sec per cm⁻⁵ reduction in pulmonary vascular resistance from baseline and an average cut in pulmonary artery pressure of 13.9 mm Hg from baseline, compared with placebo, a result that’s “unheard of,” Dr. Hoeper said in a press conference during the meeting.

“With other tested agents we usually see very little improvement in pulmonary artery pressure. This is a signal that we achieved some reversing of the pathological changes in the pulmonary vessels that lead to” PAH, he added.

Simultaneously with his report the findings also appeared online in the New England Journal of Medicine.
 

‘A new hope’ for patients with PAH

Based on the reported findings, sotatercept is a “very exciting boutique molecule” that will “offer patients with PAH a very exciting new treatment,” commented Rhonda Cooper-DeHoff, PharmD, a designated discussant and a researcher at the University of Florida, Gainesville.

Mitchel L. Zoler/MDedge News

“This study is a new hope for patients with PAH. Until now, they’ve had really bad outcomes, but [in this study] we see significant differences in 6MWD, hemodynamics, and risk factors. Overall, I think the benefit is greater than the risk” it may pose to patients through potential adverse effects, commented Julia Grapsa, MD, PhD, a cardiologist at St. Thomas Hospital in London, and another discussant at the meeting.

“The results are impressive” and “encouraging,” and “suggest that sotatercept may represent a new and clinically consequential addition to current medications for PAH,” wrote three clinicians from Canyons Region Intermountain Medical Center in Murray, Utah, in an editorial that accompanied the published report.

But the authors of the editorial also raised several cautions and concerns. They questioned the generalizability of the findings, noting that the patients with PAH enrolled in the study were all adults who were clinically stable and an average of more than 8 years out from their initial PAH diagnosis, and more than 90% were on stable treatment for PAH with two or three agents specific for treating the disorder. The study cohort also had a disproportionately high enrollment of patients with idiopathic (59%) or heritable (18%) forms of PAH, and the 15% of patients in the trial with connective tissue disease represented a disproportionately low prevalence of this PAH subtype.

The editorialists also called for “ongoing vigilance” for adverse effects from sotatercept treatment, although they acknowledged that the adverse effects reported to date from sotatercept are “largely reassuring.”
 

Death or clinical worsening cut by 84%

STELLAR randomized 323 patients at 91 sites in 21 countries with WHO Group 1 PAH and with WHO functional class II or III disease to receive either sotatercept or placebo for 24 weeks, with an option for treatment to continue beyond that until the last patient in the study reached 24 weeks on treatment, resulting in an overall median treatment duration of nearly 33 weeks.

In addition to the significant result for the primary endpoint, the 163 patients who received sotatercept had significant improvements, compared with 160 placebo-treated patients, for eight of nine secondary endpoints. The only secondary endpoint with a neutral result was for a measure of cognitive and emotional wellbeing, a parameter that was already at a normal level at baseline in most enrolled patients, Dr. Hoeper explained.

The incidence of either death or an event indicative of clinical worsening during the overall median follow-up of almost 33 weeks was 26.3% among the control patients and 5.5% among those who received sotatercept. This translated into a significant reduction for this endpoint of 84% with sotatercept treatment, compared with placebo.

The rates of treatment-emergent adverse events leading to discontinuation were roughly the same in the control and sotatercept arms, and the incidence of severe or serious treatment-emergent adverse events was higher among the control patients.

The most common adverse event on sotatercept was bleeding events, which occurred in 32% of those on sotatercept and in 16% of the control patients, but the events in the sotatercept arm were “mostly mild,” said Dr. Hoeper. The next most frequent adverse event during sotatercept treatment was appearance of telangiectasias, which occurred in 14% of those on sotatercept and in 4% of control patients.

“It’s an uncommon adverse event profile, but not unexpected for a drug with its mechanism of action,” he said.

Drug binds activin, a pathologic driver of PAH

Sotatercept is an engineered molecule that combines a section of a human immunoglobulin G molecule with a portion of the receptor for activin. This structure allows sotatercept to bind free activin molecules in a patient’s blood, thereby removing a key driver of the pulmonary vascular wall remodeling that is at the pathologic root of PAH.

“Hyperproliferation of blood vessel–wall cells” caused by activin signaling “is perhaps the most important driver of PAH,” Dr. Hoeper said. “Sotatercept allows us for the first time to target the underlying mechanism behind PAH.”

Still ongoing are the HYPERION and ZENITH phase 3 trials of sotatercept. HYPERION is enrolling patients with newly diagnosed or high-risk PAH and is expected to complete in 2028. ZENITH is enrolling patients with more advanced PAH and a higher mortality risk, with results expected in 2026.

Sotatercept has received “Breakthrough Therapy” designation and “Orphan Drug” designation by the Food and Drug Administration, and “Priority Medicines” designation and “Orphan Drug” designation by the European Medicines Agency for the treatment of PAH. One recent review estimated a worldwide PAH prevalence of about 3-4 cases/100,000, which for the United States translates into a total prevalence of perhaps 10,000-15,000 affected people.

STELLAR was funded by Acceleron Pharma, a subsidiary of Merck. Dr. Hoeper is a consultant to Acceleron. Dr. Cooper-DeHoff, Dr. Grapsa, and the authors of the editorial on STELLAR have no relevant disclosures.

NEW ORLEANS – An investigational, first-in class agent that delivers a completely new type of intervention to patients with pulmonary arterial hypertension (PAH) scored a clear win in the STELLAR trial, the first to complete among three phase 3 trials that are testing this agent.

Sotatercept, administered subcutaneously every 3 weeks for 24 weeks, improved from baseline average 6-minute walk distance (6MWD) by a significant and clinically meaningful 40.8 meters, compared with placebo, for the trial’s primary efficacy endpoint (P < .001). The treatment also “delivered broad clinical benefit across multiple domains including hemodynamics, World Health Organization functional class, disease biomarkers, risk scores and patient-reported outcomes,” Marius M. Hoeper, MD, said at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Mitchel L. Zoler/MDedge News

“These results establish the clinical utility of sotatercept, administered in combination with approved PAH therapies, as a new treatment for PAH,” added Dr. Hoeper, professor and deputy director of the department of respiratory medicine at Hannover (Germany) Medical School,

“The most important aspect was the hemodynamic improvement,” with sotatercept treatment, which led to an average 235 dyn/sec per cm⁻⁵ reduction in pulmonary vascular resistance from baseline and an average cut in pulmonary artery pressure of 13.9 mm Hg from baseline, compared with placebo, a result that’s “unheard of,” Dr. Hoeper said in a press conference during the meeting.

“With other tested agents we usually see very little improvement in pulmonary artery pressure. This is a signal that we achieved some reversing of the pathological changes in the pulmonary vessels that lead to” PAH, he added.

Simultaneously with his report the findings also appeared online in the New England Journal of Medicine.
 

‘A new hope’ for patients with PAH

Based on the reported findings, sotatercept is a “very exciting boutique molecule” that will “offer patients with PAH a very exciting new treatment,” commented Rhonda Cooper-DeHoff, PharmD, a designated discussant and a researcher at the University of Florida, Gainesville.

Mitchel L. Zoler/MDedge News

“This study is a new hope for patients with PAH. Until now, they’ve had really bad outcomes, but [in this study] we see significant differences in 6MWD, hemodynamics, and risk factors. Overall, I think the benefit is greater than the risk” it may pose to patients through potential adverse effects, commented Julia Grapsa, MD, PhD, a cardiologist at St. Thomas Hospital in London, and another discussant at the meeting.

“The results are impressive” and “encouraging,” and “suggest that sotatercept may represent a new and clinically consequential addition to current medications for PAH,” wrote three clinicians from Canyons Region Intermountain Medical Center in Murray, Utah, in an editorial that accompanied the published report.

But the authors of the editorial also raised several cautions and concerns. They questioned the generalizability of the findings, noting that the patients with PAH enrolled in the study were all adults who were clinically stable and an average of more than 8 years out from their initial PAH diagnosis, and more than 90% were on stable treatment for PAH with two or three agents specific for treating the disorder. The study cohort also had a disproportionately high enrollment of patients with idiopathic (59%) or heritable (18%) forms of PAH, and the 15% of patients in the trial with connective tissue disease represented a disproportionately low prevalence of this PAH subtype.

The editorialists also called for “ongoing vigilance” for adverse effects from sotatercept treatment, although they acknowledged that the adverse effects reported to date from sotatercept are “largely reassuring.”
 

Death or clinical worsening cut by 84%

STELLAR randomized 323 patients at 91 sites in 21 countries with WHO Group 1 PAH and with WHO functional class II or III disease to receive either sotatercept or placebo for 24 weeks, with an option for treatment to continue beyond that until the last patient in the study reached 24 weeks on treatment, resulting in an overall median treatment duration of nearly 33 weeks.

In addition to the significant result for the primary endpoint, the 163 patients who received sotatercept had significant improvements, compared with 160 placebo-treated patients, for eight of nine secondary endpoints. The only secondary endpoint with a neutral result was for a measure of cognitive and emotional wellbeing, a parameter that was already at a normal level at baseline in most enrolled patients, Dr. Hoeper explained.

The incidence of either death or an event indicative of clinical worsening during the overall median follow-up of almost 33 weeks was 26.3% among the control patients and 5.5% among those who received sotatercept. This translated into a significant reduction for this endpoint of 84% with sotatercept treatment, compared with placebo.

The rates of treatment-emergent adverse events leading to discontinuation were roughly the same in the control and sotatercept arms, and the incidence of severe or serious treatment-emergent adverse events was higher among the control patients.

The most common adverse event on sotatercept was bleeding events, which occurred in 32% of those on sotatercept and in 16% of the control patients, but the events in the sotatercept arm were “mostly mild,” said Dr. Hoeper. The next most frequent adverse event during sotatercept treatment was appearance of telangiectasias, which occurred in 14% of those on sotatercept and in 4% of control patients.

“It’s an uncommon adverse event profile, but not unexpected for a drug with its mechanism of action,” he said.

Drug binds activin, a pathologic driver of PAH

Sotatercept is an engineered molecule that combines a section of a human immunoglobulin G molecule with a portion of the receptor for activin. This structure allows sotatercept to bind free activin molecules in a patient’s blood, thereby removing a key driver of the pulmonary vascular wall remodeling that is at the pathologic root of PAH.

“Hyperproliferation of blood vessel–wall cells” caused by activin signaling “is perhaps the most important driver of PAH,” Dr. Hoeper said. “Sotatercept allows us for the first time to target the underlying mechanism behind PAH.”

Still ongoing are the HYPERION and ZENITH phase 3 trials of sotatercept. HYPERION is enrolling patients with newly diagnosed or high-risk PAH and is expected to complete in 2028. ZENITH is enrolling patients with more advanced PAH and a higher mortality risk, with results expected in 2026.

Sotatercept has received “Breakthrough Therapy” designation and “Orphan Drug” designation by the Food and Drug Administration, and “Priority Medicines” designation and “Orphan Drug” designation by the European Medicines Agency for the treatment of PAH. One recent review estimated a worldwide PAH prevalence of about 3-4 cases/100,000, which for the United States translates into a total prevalence of perhaps 10,000-15,000 affected people.

STELLAR was funded by Acceleron Pharma, a subsidiary of Merck. Dr. Hoeper is a consultant to Acceleron. Dr. Cooper-DeHoff, Dr. Grapsa, and the authors of the editorial on STELLAR have no relevant disclosures.

Adults with type 2 diabetes treated with an SGLT2 inhibitor had roughly a third fewer episodes of acute kidney injury (AKI) compared with matched people with type 2 diabetes treated with a DPP4 inhibitor, in an analysis of health insurance data from more than 100,000 Taiwan residents during 2016-2018.

The findings add to, and expand on, prior evidence that treatment with an agent from the sodium-glucose cotransporter 2 (SGLT2) inhibitor class cuts the incidence of AKI, say the authors of the report, which was recently published in JAMA Network Open.

The long-term risk for AKI among people with type 2 diabetes treated with an SGLT2 inhibitor “appears to be quite low” compared with adults who received an agent from the dipeptidyl peptidase 4 (DPP4) inhibitor class.

Treatment with an SGLT2 inhibitor – such as canagliflozin (Invokana), dapagliflozin (Farxiga), or empagliflozin (Jardiance) – causes a transient drop in kidney function that manifests as a temporary dip in estimated glomerular filtration rate, which caused concerns about AKI when the drugs were first introduced.

Indeed, canagliflozin and dapagliflozin had warnings strengthened 7 years ago by the Food and Drug Administration in a Drug Safety Communication for accumulating reports of AKI linked to their use.

More recent experience has calmed AKI concerns, however.

Commenting on the new study, F. Perry Wilson, MD, a nephrologist at Yale University, New Haven, Conn., said: “It’s a nice piece of data to demonstrate that the long-term risk from SGLT2 inhibitor treatment is low.” Dr. Wilson was not involved with the new study.

The Taiwan study found a cumulative incidence of AKI events during about 2.5 years of follow-up of 5.55 events/1,000 patient-years among adults with type 2 diabetes receiving an SGLT2 inhibitor and 7.88 events/1,000 patient-years among those taking a DPP4 inhibitor such as sitagliptin (Januvia).

Main barrier to SGLT2 inhibitor use is unfamiliarity, not AKI risk

“My impression is that the main barrier to wider use of the SGLT2 inhibitor class is not a perceived risk for causing AKI, but rather ongoing unfamiliarity with the class,” Dr. Wilson said in an interview.

Although he sees “relatively broad comfort with and enthusiasm for the class among nephrologists and cardiologists,” routine prescribing does not seem to have caught on nearly as much among primary care physicians, he said.

Clinicians in primary care “still perceive the SGLT2 inhibitor class as something of a ‘specialty drug,’ and they defer initiating it on that basis,” Dr. Wilson observed. “That’s probably not a good thing,” as many people with type 2 diabetes do not have access to a specialized clinician who might be more amenable to prescribing an SGLT2 inhibitor.

One example of the lag in SGLT2 inhibitor uptake for people with type 2 diabetes in practice was a recent report from the Centers for Disease Control and Prevention published in Annals of Internal Medicine. Researchers identified a representative U.S. sample of 1,330 adults with type 2 diabetes studied in depth during 2017-2020, of whom 82% fulfilled criteria published in 2022 for receiving treatment with an SGLT2 inhibitor. Despite this high prevalence of medical appropriateness, a scant 5.3% of those with a recommended indication actually received an agent from this class.

Early AKI concern has diminished

Results from more recent studies, such as a 2019 meta-analysis of more than 100 randomized studies and four large observational studies that together included about 180,000 people receiving SGLT2 inhibitor treatment, showed the opposite of SGLT2 inhibitor treatment triggering AKI.

In the trials, people taking an SGLT2 inhibitor had a relative 25% lower rate of AKI events, while in the observational studies, SGLT2 inhibitor treatment was linked with a 60% relative reduction in AKI. The study also found that SGLT2 inhibitor use in the trials was linked with a significant 20% relative increase in the incidence of low fluid volume.

Despite accumulated evidence exonerating AKI risk, U.S. labels for canagliflozin, dapagliflozin, and empagliflozin continue to cite AKI as a potential adverse reaction, especially in patients who undergo volume depletion while on SGLT2 inhibitor treatment.

The new Taiwan study used data from the country’s National Health Insurance Research Database. Out of more than 250,000 adults with type 2 diabetes in the system from May 2016 to December 2018, the researchers identified 52,231 propensity-score matched pairs of people where one was on treatment with an SGLT2 inhibitor and the other with a DPP4 inhibitor.

During follow-up, 856 of these people (0.8%) had an AKI event, including 102 people with AKI that required dialysis.

A logistic regression analysis that adjusted for 16 potential confounders showed that SGLT2 inhibitor treatment linked with a significant 34% reduction in AKI events compared with DPP4 inhibitor treatment, as well as with a significant 44% relative risk reduction in the incidence of AKI events requiring dialysis, reported the authors from several medical institutions in Taiwan.

The study’s main limitation was its reliance on “quite insensitive” administrative coding data to identify AKI cases, said Dr. Wilson.

He noted that although concern about AKI events secondary to SGLT2 inhibitor treatment is uncommon among U.S. clinicians they do worry about the potential risk for fungal infections, urinary tract infection, or gangrene in people with diabetes who receive an agent from this class.

The study received no commercial funding, and none of the authors had disclosures. Dr. Wilson has reported receiving research funding from AstraZeneca, Boehringer Ingelheim, Vifor, and Whoop.

A version of this article originally appeared on Medscape.com.

Adults with type 2 diabetes treated with an SGLT2 inhibitor had roughly a third fewer episodes of acute kidney injury (AKI) compared with matched people with type 2 diabetes treated with a DPP4 inhibitor, in an analysis of health insurance data from more than 100,000 Taiwan residents during 2016-2018.

The findings add to, and expand on, prior evidence that treatment with an agent from the sodium-glucose cotransporter 2 (SGLT2) inhibitor class cuts the incidence of AKI, say the authors of the report, which was recently published in JAMA Network Open.

The long-term risk for AKI among people with type 2 diabetes treated with an SGLT2 inhibitor “appears to be quite low” compared with adults who received an agent from the dipeptidyl peptidase 4 (DPP4) inhibitor class.

Treatment with an SGLT2 inhibitor – such as canagliflozin (Invokana), dapagliflozin (Farxiga), or empagliflozin (Jardiance) – causes a transient drop in kidney function that manifests as a temporary dip in estimated glomerular filtration rate, which caused concerns about AKI when the drugs were first introduced.

Indeed, canagliflozin and dapagliflozin had warnings strengthened 7 years ago by the Food and Drug Administration in a Drug Safety Communication for accumulating reports of AKI linked to their use.

More recent experience has calmed AKI concerns, however.

Commenting on the new study, F. Perry Wilson, MD, a nephrologist at Yale University, New Haven, Conn., said: “It’s a nice piece of data to demonstrate that the long-term risk from SGLT2 inhibitor treatment is low.” Dr. Wilson was not involved with the new study.

The Taiwan study found a cumulative incidence of AKI events during about 2.5 years of follow-up of 5.55 events/1,000 patient-years among adults with type 2 diabetes receiving an SGLT2 inhibitor and 7.88 events/1,000 patient-years among those taking a DPP4 inhibitor such as sitagliptin (Januvia).

Main barrier to SGLT2 inhibitor use is unfamiliarity, not AKI risk

“My impression is that the main barrier to wider use of the SGLT2 inhibitor class is not a perceived risk for causing AKI, but rather ongoing unfamiliarity with the class,” Dr. Wilson said in an interview.

Although he sees “relatively broad comfort with and enthusiasm for the class among nephrologists and cardiologists,” routine prescribing does not seem to have caught on nearly as much among primary care physicians, he said.

Clinicians in primary care “still perceive the SGLT2 inhibitor class as something of a ‘specialty drug,’ and they defer initiating it on that basis,” Dr. Wilson observed. “That’s probably not a good thing,” as many people with type 2 diabetes do not have access to a specialized clinician who might be more amenable to prescribing an SGLT2 inhibitor.

One example of the lag in SGLT2 inhibitor uptake for people with type 2 diabetes in practice was a recent report from the Centers for Disease Control and Prevention published in Annals of Internal Medicine. Researchers identified a representative U.S. sample of 1,330 adults with type 2 diabetes studied in depth during 2017-2020, of whom 82% fulfilled criteria published in 2022 for receiving treatment with an SGLT2 inhibitor. Despite this high prevalence of medical appropriateness, a scant 5.3% of those with a recommended indication actually received an agent from this class.

Early AKI concern has diminished

Results from more recent studies, such as a 2019 meta-analysis of more than 100 randomized studies and four large observational studies that together included about 180,000 people receiving SGLT2 inhibitor treatment, showed the opposite of SGLT2 inhibitor treatment triggering AKI.

In the trials, people taking an SGLT2 inhibitor had a relative 25% lower rate of AKI events, while in the observational studies, SGLT2 inhibitor treatment was linked with a 60% relative reduction in AKI. The study also found that SGLT2 inhibitor use in the trials was linked with a significant 20% relative increase in the incidence of low fluid volume.

Despite accumulated evidence exonerating AKI risk, U.S. labels for canagliflozin, dapagliflozin, and empagliflozin continue to cite AKI as a potential adverse reaction, especially in patients who undergo volume depletion while on SGLT2 inhibitor treatment.

The new Taiwan study used data from the country’s National Health Insurance Research Database. Out of more than 250,000 adults with type 2 diabetes in the system from May 2016 to December 2018, the researchers identified 52,231 propensity-score matched pairs of people where one was on treatment with an SGLT2 inhibitor and the other with a DPP4 inhibitor.

During follow-up, 856 of these people (0.8%) had an AKI event, including 102 people with AKI that required dialysis.

A logistic regression analysis that adjusted for 16 potential confounders showed that SGLT2 inhibitor treatment linked with a significant 34% reduction in AKI events compared with DPP4 inhibitor treatment, as well as with a significant 44% relative risk reduction in the incidence of AKI events requiring dialysis, reported the authors from several medical institutions in Taiwan.

The study’s main limitation was its reliance on “quite insensitive” administrative coding data to identify AKI cases, said Dr. Wilson.

He noted that although concern about AKI events secondary to SGLT2 inhibitor treatment is uncommon among U.S. clinicians they do worry about the potential risk for fungal infections, urinary tract infection, or gangrene in people with diabetes who receive an agent from this class.

The study received no commercial funding, and none of the authors had disclosures. Dr. Wilson has reported receiving research funding from AstraZeneca, Boehringer Ingelheim, Vifor, and Whoop.

A version of this article originally appeared on Medscape.com.

Adults with type 2 diabetes treated with an SGLT2 inhibitor had roughly a third fewer episodes of acute kidney injury (AKI) compared with matched people with type 2 diabetes treated with a DPP4 inhibitor, in an analysis of health insurance data from more than 100,000 Taiwan residents during 2016-2018.

The findings add to, and expand on, prior evidence that treatment with an agent from the sodium-glucose cotransporter 2 (SGLT2) inhibitor class cuts the incidence of AKI, say the authors of the report, which was recently published in JAMA Network Open.

The long-term risk for AKI among people with type 2 diabetes treated with an SGLT2 inhibitor “appears to be quite low” compared with adults who received an agent from the dipeptidyl peptidase 4 (DPP4) inhibitor class.

Treatment with an SGLT2 inhibitor – such as canagliflozin (Invokana), dapagliflozin (Farxiga), or empagliflozin (Jardiance) – causes a transient drop in kidney function that manifests as a temporary dip in estimated glomerular filtration rate, which caused concerns about AKI when the drugs were first introduced.

Indeed, canagliflozin and dapagliflozin had warnings strengthened 7 years ago by the Food and Drug Administration in a Drug Safety Communication for accumulating reports of AKI linked to their use.

More recent experience has calmed AKI concerns, however.

Commenting on the new study, F. Perry Wilson, MD, a nephrologist at Yale University, New Haven, Conn., said: “It’s a nice piece of data to demonstrate that the long-term risk from SGLT2 inhibitor treatment is low.” Dr. Wilson was not involved with the new study.

The Taiwan study found a cumulative incidence of AKI events during about 2.5 years of follow-up of 5.55 events/1,000 patient-years among adults with type 2 diabetes receiving an SGLT2 inhibitor and 7.88 events/1,000 patient-years among those taking a DPP4 inhibitor such as sitagliptin (Januvia).

Main barrier to SGLT2 inhibitor use is unfamiliarity, not AKI risk

“My impression is that the main barrier to wider use of the SGLT2 inhibitor class is not a perceived risk for causing AKI, but rather ongoing unfamiliarity with the class,” Dr. Wilson said in an interview.

Although he sees “relatively broad comfort with and enthusiasm for the class among nephrologists and cardiologists,” routine prescribing does not seem to have caught on nearly as much among primary care physicians, he said.

Clinicians in primary care “still perceive the SGLT2 inhibitor class as something of a ‘specialty drug,’ and they defer initiating it on that basis,” Dr. Wilson observed. “That’s probably not a good thing,” as many people with type 2 diabetes do not have access to a specialized clinician who might be more amenable to prescribing an SGLT2 inhibitor.

One example of the lag in SGLT2 inhibitor uptake for people with type 2 diabetes in practice was a recent report from the Centers for Disease Control and Prevention published in Annals of Internal Medicine. Researchers identified a representative U.S. sample of 1,330 adults with type 2 diabetes studied in depth during 2017-2020, of whom 82% fulfilled criteria published in 2022 for receiving treatment with an SGLT2 inhibitor. Despite this high prevalence of medical appropriateness, a scant 5.3% of those with a recommended indication actually received an agent from this class.

Early AKI concern has diminished

Results from more recent studies, such as a 2019 meta-analysis of more than 100 randomized studies and four large observational studies that together included about 180,000 people receiving SGLT2 inhibitor treatment, showed the opposite of SGLT2 inhibitor treatment triggering AKI.

In the trials, people taking an SGLT2 inhibitor had a relative 25% lower rate of AKI events, while in the observational studies, SGLT2 inhibitor treatment was linked with a 60% relative reduction in AKI. The study also found that SGLT2 inhibitor use in the trials was linked with a significant 20% relative increase in the incidence of low fluid volume.

Despite accumulated evidence exonerating AKI risk, U.S. labels for canagliflozin, dapagliflozin, and empagliflozin continue to cite AKI as a potential adverse reaction, especially in patients who undergo volume depletion while on SGLT2 inhibitor treatment.

The new Taiwan study used data from the country’s National Health Insurance Research Database. Out of more than 250,000 adults with type 2 diabetes in the system from May 2016 to December 2018, the researchers identified 52,231 propensity-score matched pairs of people where one was on treatment with an SGLT2 inhibitor and the other with a DPP4 inhibitor.

During follow-up, 856 of these people (0.8%) had an AKI event, including 102 people with AKI that required dialysis.

A logistic regression analysis that adjusted for 16 potential confounders showed that SGLT2 inhibitor treatment linked with a significant 34% reduction in AKI events compared with DPP4 inhibitor treatment, as well as with a significant 44% relative risk reduction in the incidence of AKI events requiring dialysis, reported the authors from several medical institutions in Taiwan.

The study’s main limitation was its reliance on “quite insensitive” administrative coding data to identify AKI cases, said Dr. Wilson.

He noted that although concern about AKI events secondary to SGLT2 inhibitor treatment is uncommon among U.S. clinicians they do worry about the potential risk for fungal infections, urinary tract infection, or gangrene in people with diabetes who receive an agent from this class.

The study received no commercial funding, and none of the authors had disclosures. Dr. Wilson has reported receiving research funding from AstraZeneca, Boehringer Ingelheim, Vifor, and Whoop.

A version of this article originally appeared on Medscape.com.

NEW ORLEANS – A wearable device that monitors thoracic fluid and can signal elevated levels can improve outcomes after heart failure hospitalization, according to a comparative but nonrandomized trial.

In this study, management adjustments made in response to a threshold alert from the device led to several improvements in outcome at 90 days, including a significant 38% reduction in the primary outcome of rehospitalization, relative to controls (P = .02), reported John P. Boehmer, MD, at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Ted Bosworth/MDedge News

The same relative risk reduction at 90 days was observed for a composite outcome of time to first hospitalization, visit to an emergency room, or death (hazard ratio, 0.62; P = .03).

Quality of life, as measured with the Kansas City Cardiomyopathy Questionnaire (KCCQ), improved steadily in both the experimental and control arm over the 90-day study, but the curves separated at about 30 days, Dr. Boehmer reported. By the end of the study, the mean KCCQ difference was 12 points favoring the experimental arm on a scale in which 5 points is considered clinically meaningful.
 

70% report improved quality of life

“Responder analysis revealed that nearly 70% of patients in the arm managed with the monitor reported a clinically meaningful improvement in quality of life, compared to 50% of patients in the control arm,” said Dr. Boehmer, professor of medicine and surgery at Penn State Health, Hershey.

Fluid overload is an indication of worsening disease and a frequent cause of heart failure hospitalization. The Zoll Heart Failure Monitoring System (HFMS) that was tested in this study already has regulatory approval. It is equipped to monitor several biomarkers, including heart rate and respiration rate, but its ability to measure lung fluid through low electromagnetic radiofrequency pulses was the function of interest for this study.

In this nonrandomized study, called Benefits of Microcor in Ambulatory

Decompensated Heart Failure (BMAD), a control arm was enrolled first. By monitoring the initial patients enrolled in the control arm, the investigators established a threshold of thoracic fluid that would be used to trigger an alert in the intervention arm. This ultimately was defined as 3 standard deviations from the population mean.

Patients were eligible for this study if they were discharged from a hospital with heart failure in the previous 10 days. Of exclusion criteria, a short life expectancy (< 1 year) and a wearable cardiac defibrillator were notable. Left ventricular ejection fraction (LVEF) was not considered for inclusion or exclusion.

All subjects participated in weekly phone calls and monthly office visits. However, both investigators and patients were blinded to the device data in the control arm. Conversely, subjects and investigators in the intervention arm were able to access data generated by the device through a secure website.

Of the 245 eligible patients in the control arm, 168 were available for evaluation at 90 days. Among the 249 eligible patients in the intervention arm, 176 were included in the 90-day evaluation. Of those who were not available, the most common reason was study withdrawal. About 20% died before the 90-day evaluation.

The majority of patients in both arms were in class III or IV heart failure. About half had LVEF less than 40%, and more than 40% of patients in each group had chronic kidney disease (CKD). Roughly 55% of patients were at least 65 years of age.

At 90 days, the absolute risk reduction in rehospitalization was 7%, producing a number to treat with the device of 14.3 to prevent one rehospitalization. In a subgroup stratification, the benefit was similar by age, sex, presence or absence of CKD, LVEF greater or lower than 40%, Black or non-Black race, and ischemic or nonischemic etiology.
 

Patient access to data considered a plus

If lack of randomization is a weakness of this study, the decision to unblind the data for both investigators and patients might not be, according to Lynne Stevenson, MD, director of the cardiomyopathy program, Vanderbilt University Medical Center, Nashville, Tenn.

“You might be criticized for this [allowing patients to monitor their data], but I actually think this is a strength of the study,” said Dr. Stevenson, who believes the growing trend to involve heart failure patients in self-management has been a positive direction in clinical care.

She indicated that, despite the potential bias derived from being aware of fluid fluctuations, this information might also be contributing to patient motivation for adherence and appropriate lifestyle modifications.

Biykem Bozkurt, MD, PhD, chair of cardiology at Baylor College of Medicine, Houston, made a similar point but for a different reason. She expressed concern about the work that monitoring the wearable device creates for clinicians. Despite the positive data generated by this study, Dr. Bozkurt said the device as used in the study demanded “a lot of clinical time and effort” when these are both in short supply.

Mitchel L. Zoler/MDedge News

While she called for a larger and randomized study to corroborate the results of this investigation, she also thinks that it would make sense to compare the clinical value of this device against alternative methods for monitoring heart failure, including other wearable devices. Dr. Bozkurt asserted that some of the most helpful devices from a clinical perspective might be those that patients monitor themselves.

“Hopefully in the future, we will be offering tools that provide patients information they can use without the immediate need of a clinician,” she said.

Dr. Boehmer reports financial relationships with Abbott, Boston Scientific, Medtronic, and Zoll Medical Corporation, which provided the funding for this study. Dr. Stevenson reports no potential conflicts of interest. Dr. Bozkurt reports financial relationships with Abbott, Amgen, AstraZeneca, Boehringer Ingelheim, Cardurion, LivaNova, Relypsa, Renovacor, Sanofi-Aventis, and Vifor.

NEW ORLEANS – A wearable device that monitors thoracic fluid and can signal elevated levels can improve outcomes after heart failure hospitalization, according to a comparative but nonrandomized trial.

In this study, management adjustments made in response to a threshold alert from the device led to several improvements in outcome at 90 days, including a significant 38% reduction in the primary outcome of rehospitalization, relative to controls (P = .02), reported John P. Boehmer, MD, at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Ted Bosworth/MDedge News

The same relative risk reduction at 90 days was observed for a composite outcome of time to first hospitalization, visit to an emergency room, or death (hazard ratio, 0.62; P = .03).

Quality of life, as measured with the Kansas City Cardiomyopathy Questionnaire (KCCQ), improved steadily in both the experimental and control arm over the 90-day study, but the curves separated at about 30 days, Dr. Boehmer reported. By the end of the study, the mean KCCQ difference was 12 points favoring the experimental arm on a scale in which 5 points is considered clinically meaningful.
 

70% report improved quality of life

“Responder analysis revealed that nearly 70% of patients in the arm managed with the monitor reported a clinically meaningful improvement in quality of life, compared to 50% of patients in the control arm,” said Dr. Boehmer, professor of medicine and surgery at Penn State Health, Hershey.

Fluid overload is an indication of worsening disease and a frequent cause of heart failure hospitalization. The Zoll Heart Failure Monitoring System (HFMS) that was tested in this study already has regulatory approval. It is equipped to monitor several biomarkers, including heart rate and respiration rate, but its ability to measure lung fluid through low electromagnetic radiofrequency pulses was the function of interest for this study.

In this nonrandomized study, called Benefits of Microcor in Ambulatory

Decompensated Heart Failure (BMAD), a control arm was enrolled first. By monitoring the initial patients enrolled in the control arm, the investigators established a threshold of thoracic fluid that would be used to trigger an alert in the intervention arm. This ultimately was defined as 3 standard deviations from the population mean.

Patients were eligible for this study if they were discharged from a hospital with heart failure in the previous 10 days. Of exclusion criteria, a short life expectancy (< 1 year) and a wearable cardiac defibrillator were notable. Left ventricular ejection fraction (LVEF) was not considered for inclusion or exclusion.

All subjects participated in weekly phone calls and monthly office visits. However, both investigators and patients were blinded to the device data in the control arm. Conversely, subjects and investigators in the intervention arm were able to access data generated by the device through a secure website.

Of the 245 eligible patients in the control arm, 168 were available for evaluation at 90 days. Among the 249 eligible patients in the intervention arm, 176 were included in the 90-day evaluation. Of those who were not available, the most common reason was study withdrawal. About 20% died before the 90-day evaluation.

The majority of patients in both arms were in class III or IV heart failure. About half had LVEF less than 40%, and more than 40% of patients in each group had chronic kidney disease (CKD). Roughly 55% of patients were at least 65 years of age.

At 90 days, the absolute risk reduction in rehospitalization was 7%, producing a number to treat with the device of 14.3 to prevent one rehospitalization. In a subgroup stratification, the benefit was similar by age, sex, presence or absence of CKD, LVEF greater or lower than 40%, Black or non-Black race, and ischemic or nonischemic etiology.
 

Patient access to data considered a plus

If lack of randomization is a weakness of this study, the decision to unblind the data for both investigators and patients might not be, according to Lynne Stevenson, MD, director of the cardiomyopathy program, Vanderbilt University Medical Center, Nashville, Tenn.

“You might be criticized for this [allowing patients to monitor their data], but I actually think this is a strength of the study,” said Dr. Stevenson, who believes the growing trend to involve heart failure patients in self-management has been a positive direction in clinical care.

She indicated that, despite the potential bias derived from being aware of fluid fluctuations, this information might also be contributing to patient motivation for adherence and appropriate lifestyle modifications.

Biykem Bozkurt, MD, PhD, chair of cardiology at Baylor College of Medicine, Houston, made a similar point but for a different reason. She expressed concern about the work that monitoring the wearable device creates for clinicians. Despite the positive data generated by this study, Dr. Bozkurt said the device as used in the study demanded “a lot of clinical time and effort” when these are both in short supply.

Mitchel L. Zoler/MDedge News

While she called for a larger and randomized study to corroborate the results of this investigation, she also thinks that it would make sense to compare the clinical value of this device against alternative methods for monitoring heart failure, including other wearable devices. Dr. Bozkurt asserted that some of the most helpful devices from a clinical perspective might be those that patients monitor themselves.

“Hopefully in the future, we will be offering tools that provide patients information they can use without the immediate need of a clinician,” she said.

Dr. Boehmer reports financial relationships with Abbott, Boston Scientific, Medtronic, and Zoll Medical Corporation, which provided the funding for this study. Dr. Stevenson reports no potential conflicts of interest. Dr. Bozkurt reports financial relationships with Abbott, Amgen, AstraZeneca, Boehringer Ingelheim, Cardurion, LivaNova, Relypsa, Renovacor, Sanofi-Aventis, and Vifor.

NEW ORLEANS – A wearable device that monitors thoracic fluid and can signal elevated levels can improve outcomes after heart failure hospitalization, according to a comparative but nonrandomized trial.

In this study, management adjustments made in response to a threshold alert from the device led to several improvements in outcome at 90 days, including a significant 38% reduction in the primary outcome of rehospitalization, relative to controls (P = .02), reported John P. Boehmer, MD, at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Ted Bosworth/MDedge News

The same relative risk reduction at 90 days was observed for a composite outcome of time to first hospitalization, visit to an emergency room, or death (hazard ratio, 0.62; P = .03).

Quality of life, as measured with the Kansas City Cardiomyopathy Questionnaire (KCCQ), improved steadily in both the experimental and control arm over the 90-day study, but the curves separated at about 30 days, Dr. Boehmer reported. By the end of the study, the mean KCCQ difference was 12 points favoring the experimental arm on a scale in which 5 points is considered clinically meaningful.
 

70% report improved quality of life

“Responder analysis revealed that nearly 70% of patients in the arm managed with the monitor reported a clinically meaningful improvement in quality of life, compared to 50% of patients in the control arm,” said Dr. Boehmer, professor of medicine and surgery at Penn State Health, Hershey.

Fluid overload is an indication of worsening disease and a frequent cause of heart failure hospitalization. The Zoll Heart Failure Monitoring System (HFMS) that was tested in this study already has regulatory approval. It is equipped to monitor several biomarkers, including heart rate and respiration rate, but its ability to measure lung fluid through low electromagnetic radiofrequency pulses was the function of interest for this study.

In this nonrandomized study, called Benefits of Microcor in Ambulatory

Decompensated Heart Failure (BMAD), a control arm was enrolled first. By monitoring the initial patients enrolled in the control arm, the investigators established a threshold of thoracic fluid that would be used to trigger an alert in the intervention arm. This ultimately was defined as 3 standard deviations from the population mean.

Patients were eligible for this study if they were discharged from a hospital with heart failure in the previous 10 days. Of exclusion criteria, a short life expectancy (< 1 year) and a wearable cardiac defibrillator were notable. Left ventricular ejection fraction (LVEF) was not considered for inclusion or exclusion.

All subjects participated in weekly phone calls and monthly office visits. However, both investigators and patients were blinded to the device data in the control arm. Conversely, subjects and investigators in the intervention arm were able to access data generated by the device through a secure website.

Of the 245 eligible patients in the control arm, 168 were available for evaluation at 90 days. Among the 249 eligible patients in the intervention arm, 176 were included in the 90-day evaluation. Of those who were not available, the most common reason was study withdrawal. About 20% died before the 90-day evaluation.

The majority of patients in both arms were in class III or IV heart failure. About half had LVEF less than 40%, and more than 40% of patients in each group had chronic kidney disease (CKD). Roughly 55% of patients were at least 65 years of age.

At 90 days, the absolute risk reduction in rehospitalization was 7%, producing a number to treat with the device of 14.3 to prevent one rehospitalization. In a subgroup stratification, the benefit was similar by age, sex, presence or absence of CKD, LVEF greater or lower than 40%, Black or non-Black race, and ischemic or nonischemic etiology.
 

Patient access to data considered a plus

If lack of randomization is a weakness of this study, the decision to unblind the data for both investigators and patients might not be, according to Lynne Stevenson, MD, director of the cardiomyopathy program, Vanderbilt University Medical Center, Nashville, Tenn.

“You might be criticized for this [allowing patients to monitor their data], but I actually think this is a strength of the study,” said Dr. Stevenson, who believes the growing trend to involve heart failure patients in self-management has been a positive direction in clinical care.

She indicated that, despite the potential bias derived from being aware of fluid fluctuations, this information might also be contributing to patient motivation for adherence and appropriate lifestyle modifications.

Biykem Bozkurt, MD, PhD, chair of cardiology at Baylor College of Medicine, Houston, made a similar point but for a different reason. She expressed concern about the work that monitoring the wearable device creates for clinicians. Despite the positive data generated by this study, Dr. Bozkurt said the device as used in the study demanded “a lot of clinical time and effort” when these are both in short supply.

Mitchel L. Zoler/MDedge News

While she called for a larger and randomized study to corroborate the results of this investigation, she also thinks that it would make sense to compare the clinical value of this device against alternative methods for monitoring heart failure, including other wearable devices. Dr. Bozkurt asserted that some of the most helpful devices from a clinical perspective might be those that patients monitor themselves.

“Hopefully in the future, we will be offering tools that provide patients information they can use without the immediate need of a clinician,” she said.

Dr. Boehmer reports financial relationships with Abbott, Boston Scientific, Medtronic, and Zoll Medical Corporation, which provided the funding for this study. Dr. Stevenson reports no potential conflicts of interest. Dr. Bozkurt reports financial relationships with Abbott, Amgen, AstraZeneca, Boehringer Ingelheim, Cardurion, LivaNova, Relypsa, Renovacor, Sanofi-Aventis, and Vifor.

Already commonly used in combination for the treatment of pulmonary arterial hypertension (PAH), macitentan and tadalafil are safe and effective in a fixed-dose combination even as first-line therapy, according to a randomized multicenter comparative trial.

The fixed-dose combination “led to a highly significant and marked improvement in pulmonary vascular resistance when compared to macitentan and tadalafil as monotherapies,” Kelly Chin, MD, reported at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Ted Bosworth/MDedge News

Guidelines encourage rapid PVR reductions

In practice, it is common to start treatment with either the endothelial receptor antagonist (ERA) macitentan, the phosphodiesterase-5 (PDE-5) inhibitor tadalafil, or other frequently used medications for PAH, and to then add additional treatments, according to Dr. Chin. She pointed out, however, that guidelines, including those issued jointly by the European Society of Cardiology and the European Respiratory Society, encourage rapid escalation of therapy to quickly lower pulmonary vascular resistance (PVR).

In general, both macitentan and tadalafil are well tolerated, but the advantage and the safety of rapidly reducing PVR when these are initiated together in a single pill had not been evaluated previously in a major trial. In this double-blind phase III trial, called A DUE, 187 patients in functional class II or III PAH were randomized. The three-arm study included both treatment naive patients and patients who had been on stable doses (> 3 months) of an ERA or a PDE5 inhibitor, explained Dr. Chin, director of pulmonary hypertension at the UT Southwestern, Dallas.

Treatment naive patients, representing about 53% of the study population, were randomized to 10 mg macitentan monotherapy, 40 mg tadalafil monotherapy, or a fixed-dose, single-pill combination containing both. If on a stable dose of an ERA at trial entry, patients were randomized to 10 macitentan as a monotherapy or to the fixed dose combination. Patients entering the trial already on a stable dose of a PDE5 inhibitor were randomized to 40 mg tadalafil or the combination.
 

PVR reduced twofold on combination therapy

Relative to macitentan monotherapy, the percentage change from baseline in PVR by ratio of geometric mean, which was the primary outcome, was about twice as high on the combination (45% vs. 23%) at the end of the 16-week trial. This translates into a 29% PVR reduction (hazard ratio, 0.71; P < .0001).

For combination therapy relative to tadalafil monotherapy, the advantage for the fixed dose combination (44% vs. 22%) was about the same, also providing a nearly 30% relative reduction (HR, 0.72; P < .0001).

The increases in 6-minute walk distance (6MWD) at 16 weeks, a secondary endpoint, numerically favored the combination pill over both macitentan monotherapy (52.9 vs. 39.5 meters; P = .38) and tadalafil (43.4 vs. 15.9 meters; P = .059), but only the improvement relative to tadalafil monotherapy was considered a trend.

The proportion of patients who experienced at least one serious adverse event was higher in the combination arm (14.0%) relative to single agent macitentan (8.6%) or single agent tadalafil (9.1%). The adverse events and serious adverse events more common on the combination included hypotension, fluid retention, and anemia. This latter side effect occurred in 18.7%, 2.9%, and 2.3% in the combination, macitentan monotherapy, and tadalafil arms, respectively.

Several of those invited by the ACC to discuss the paper, including Lee R. Goldberg, MD, section chief of advanced heart failure and cardiac transplant, University of Pennsylvania, Philadelphia, raised concern about the increased rate of anemia among those in the combination pill. Two of the patients (2%) treated with the combination developed a hemoglobin < 8 g/dL.

Overall, nine (8.4%) of those on the fixed-dose combination, two (4.5%) of those randomized to tadalafil monotherapy, and none of the patients randomized to macitentan discontinued therapy due to side effects.
 

Anemia risk unexpected

Based on “the unexpected signal of an anemia risk,” Biykem Bozkurt, MD, PhD, chair of cardiology at Baylor College of Medicine, Houston, said that a larger scale trial with a longer follow-up is needed. While the concept of front-loading two drugs is attractive “for the very challenging PAH population,” she called for further evaluation of this safety signal before clinicians switch from the current practice of starting with one PAH therapy before adding others.

Mitchel L. Zoler/MDedge News

In addition, Dr. Bozkurt said a more definitive study would be helpful in determining whether starting with a fixed-pill combination is better than sequential treatment to improve quality of life. Dr. Bozkurt said it is likely that the lack of significant benefit on 6MWD in this study was due to the relatively small sample size, but an improvement in this measure would be another reason to consider a front-line fixed-dose combination.

Dr. Chin, in an interview, did not agree. She agreed that a larger sample size might have yielded a significant improvement in 6MWD, but she noted this outcome was moving in the right direction and was not the primary endpoint. In her opinion, this phase 3 trial does confirm that fixed-dose combination is well tolerated, has acceptable safety, and markedly improves PVR, fulfilling the guideline goal of controlling PAH more quickly.

Dr. Chin reports financial relationships with Altavant, Arena, Gossamer Bio, Janssen, Merck, ShouTi, and United Therapeutics. Dr. Goldberg reports financial relationships with Abbott, Respicardia/Zoll, and Viscardia. Dr. Bozkurt reports financial relationships with Abbott, Amgen, AstraZeneca, Boehringer Ingelheim, Cardurion, LivaNova, Relypsa, Renovacor, Sanofi-Aventis, and Vifor.

Already commonly used in combination for the treatment of pulmonary arterial hypertension (PAH), macitentan and tadalafil are safe and effective in a fixed-dose combination even as first-line therapy, according to a randomized multicenter comparative trial.

The fixed-dose combination “led to a highly significant and marked improvement in pulmonary vascular resistance when compared to macitentan and tadalafil as monotherapies,” Kelly Chin, MD, reported at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Ted Bosworth/MDedge News

Guidelines encourage rapid PVR reductions

In practice, it is common to start treatment with either the endothelial receptor antagonist (ERA) macitentan, the phosphodiesterase-5 (PDE-5) inhibitor tadalafil, or other frequently used medications for PAH, and to then add additional treatments, according to Dr. Chin. She pointed out, however, that guidelines, including those issued jointly by the European Society of Cardiology and the European Respiratory Society, encourage rapid escalation of therapy to quickly lower pulmonary vascular resistance (PVR).

In general, both macitentan and tadalafil are well tolerated, but the advantage and the safety of rapidly reducing PVR when these are initiated together in a single pill had not been evaluated previously in a major trial. In this double-blind phase III trial, called A DUE, 187 patients in functional class II or III PAH were randomized. The three-arm study included both treatment naive patients and patients who had been on stable doses (> 3 months) of an ERA or a PDE5 inhibitor, explained Dr. Chin, director of pulmonary hypertension at the UT Southwestern, Dallas.

Treatment naive patients, representing about 53% of the study population, were randomized to 10 mg macitentan monotherapy, 40 mg tadalafil monotherapy, or a fixed-dose, single-pill combination containing both. If on a stable dose of an ERA at trial entry, patients were randomized to 10 macitentan as a monotherapy or to the fixed dose combination. Patients entering the trial already on a stable dose of a PDE5 inhibitor were randomized to 40 mg tadalafil or the combination.
 

PVR reduced twofold on combination therapy

Relative to macitentan monotherapy, the percentage change from baseline in PVR by ratio of geometric mean, which was the primary outcome, was about twice as high on the combination (45% vs. 23%) at the end of the 16-week trial. This translates into a 29% PVR reduction (hazard ratio, 0.71; P < .0001).

For combination therapy relative to tadalafil monotherapy, the advantage for the fixed dose combination (44% vs. 22%) was about the same, also providing a nearly 30% relative reduction (HR, 0.72; P < .0001).

The increases in 6-minute walk distance (6MWD) at 16 weeks, a secondary endpoint, numerically favored the combination pill over both macitentan monotherapy (52.9 vs. 39.5 meters; P = .38) and tadalafil (43.4 vs. 15.9 meters; P = .059), but only the improvement relative to tadalafil monotherapy was considered a trend.

The proportion of patients who experienced at least one serious adverse event was higher in the combination arm (14.0%) relative to single agent macitentan (8.6%) or single agent tadalafil (9.1%). The adverse events and serious adverse events more common on the combination included hypotension, fluid retention, and anemia. This latter side effect occurred in 18.7%, 2.9%, and 2.3% in the combination, macitentan monotherapy, and tadalafil arms, respectively.

Several of those invited by the ACC to discuss the paper, including Lee R. Goldberg, MD, section chief of advanced heart failure and cardiac transplant, University of Pennsylvania, Philadelphia, raised concern about the increased rate of anemia among those in the combination pill. Two of the patients (2%) treated with the combination developed a hemoglobin < 8 g/dL.

Overall, nine (8.4%) of those on the fixed-dose combination, two (4.5%) of those randomized to tadalafil monotherapy, and none of the patients randomized to macitentan discontinued therapy due to side effects.
 

Anemia risk unexpected

Based on “the unexpected signal of an anemia risk,” Biykem Bozkurt, MD, PhD, chair of cardiology at Baylor College of Medicine, Houston, said that a larger scale trial with a longer follow-up is needed. While the concept of front-loading two drugs is attractive “for the very challenging PAH population,” she called for further evaluation of this safety signal before clinicians switch from the current practice of starting with one PAH therapy before adding others.

Mitchel L. Zoler/MDedge News

In addition, Dr. Bozkurt said a more definitive study would be helpful in determining whether starting with a fixed-pill combination is better than sequential treatment to improve quality of life. Dr. Bozkurt said it is likely that the lack of significant benefit on 6MWD in this study was due to the relatively small sample size, but an improvement in this measure would be another reason to consider a front-line fixed-dose combination.

Dr. Chin, in an interview, did not agree. She agreed that a larger sample size might have yielded a significant improvement in 6MWD, but she noted this outcome was moving in the right direction and was not the primary endpoint. In her opinion, this phase 3 trial does confirm that fixed-dose combination is well tolerated, has acceptable safety, and markedly improves PVR, fulfilling the guideline goal of controlling PAH more quickly.

Dr. Chin reports financial relationships with Altavant, Arena, Gossamer Bio, Janssen, Merck, ShouTi, and United Therapeutics. Dr. Goldberg reports financial relationships with Abbott, Respicardia/Zoll, and Viscardia. Dr. Bozkurt reports financial relationships with Abbott, Amgen, AstraZeneca, Boehringer Ingelheim, Cardurion, LivaNova, Relypsa, Renovacor, Sanofi-Aventis, and Vifor.

Already commonly used in combination for the treatment of pulmonary arterial hypertension (PAH), macitentan and tadalafil are safe and effective in a fixed-dose combination even as first-line therapy, according to a randomized multicenter comparative trial.

The fixed-dose combination “led to a highly significant and marked improvement in pulmonary vascular resistance when compared to macitentan and tadalafil as monotherapies,” Kelly Chin, MD, reported at the joint scientific sessions of the American College of Cardiology and the World Heart Federation.

Ted Bosworth/MDedge News

Guidelines encourage rapid PVR reductions

In practice, it is common to start treatment with either the endothelial receptor antagonist (ERA) macitentan, the phosphodiesterase-5 (PDE-5) inhibitor tadalafil, or other frequently used medications for PAH, and to then add additional treatments, according to Dr. Chin. She pointed out, however, that guidelines, including those issued jointly by the European Society of Cardiology and the European Respiratory Society, encourage rapid escalation of therapy to quickly lower pulmonary vascular resistance (PVR).

In general, both macitentan and tadalafil are well tolerated, but the advantage and the safety of rapidly reducing PVR when these are initiated together in a single pill had not been evaluated previously in a major trial. In this double-blind phase III trial, called A DUE, 187 patients in functional class II or III PAH were randomized. The three-arm study included both treatment naive patients and patients who had been on stable doses (> 3 months) of an ERA or a PDE5 inhibitor, explained Dr. Chin, director of pulmonary hypertension at the UT Southwestern, Dallas.

Treatment naive patients, representing about 53% of the study population, were randomized to 10 mg macitentan monotherapy, 40 mg tadalafil monotherapy, or a fixed-dose, single-pill combination containing both. If on a stable dose of an ERA at trial entry, patients were randomized to 10 macitentan as a monotherapy or to the fixed dose combination. Patients entering the trial already on a stable dose of a PDE5 inhibitor were randomized to 40 mg tadalafil or the combination.
 

PVR reduced twofold on combination therapy

Relative to macitentan monotherapy, the percentage change from baseline in PVR by ratio of geometric mean, which was the primary outcome, was about twice as high on the combination (45% vs. 23%) at the end of the 16-week trial. This translates into a 29% PVR reduction (hazard ratio, 0.71; P < .0001).

For combination therapy relative to tadalafil monotherapy, the advantage for the fixed dose combination (44% vs. 22%) was about the same, also providing a nearly 30% relative reduction (HR, 0.72; P < .0001).

The increases in 6-minute walk distance (6MWD) at 16 weeks, a secondary endpoint, numerically favored the combination pill over both macitentan monotherapy (52.9 vs. 39.5 meters; P = .38) and tadalafil (43.4 vs. 15.9 meters; P = .059), but only the improvement relative to tadalafil monotherapy was considered a trend.

The proportion of patients who experienced at least one serious adverse event was higher in the combination arm (14.0%) relative to single agent macitentan (8.6%) or single agent tadalafil (9.1%). The adverse events and serious adverse events more common on the combination included hypotension, fluid retention, and anemia. This latter side effect occurred in 18.7%, 2.9%, and 2.3% in the combination, macitentan monotherapy, and tadalafil arms, respectively.

Several of those invited by the ACC to discuss the paper, including Lee R. Goldberg, MD, section chief of advanced heart failure and cardiac transplant, University of Pennsylvania, Philadelphia, raised concern about the increased rate of anemia among those in the combination pill. Two of the patients (2%) treated with the combination developed a hemoglobin < 8 g/dL.

Overall, nine (8.4%) of those on the fixed-dose combination, two (4.5%) of those randomized to tadalafil monotherapy, and none of the patients randomized to macitentan discontinued therapy due to side effects.
 

Anemia risk unexpected

Based on “the unexpected signal of an anemia risk,” Biykem Bozkurt, MD, PhD, chair of cardiology at Baylor College of Medicine, Houston, said that a larger scale trial with a longer follow-up is needed. While the concept of front-loading two drugs is attractive “for the very challenging PAH population,” she called for further evaluation of this safety signal before clinicians switch from the current practice of starting with one PAH therapy before adding others.

Mitchel L. Zoler/MDedge News

In addition, Dr. Bozkurt said a more definitive study would be helpful in determining whether starting with a fixed-pill combination is better than sequential treatment to improve quality of life. Dr. Bozkurt said it is likely that the lack of significant benefit on 6MWD in this study was due to the relatively small sample size, but an improvement in this measure would be another reason to consider a front-line fixed-dose combination.

Dr. Chin, in an interview, did not agree. She agreed that a larger sample size might have yielded a significant improvement in 6MWD, but she noted this outcome was moving in the right direction and was not the primary endpoint. In her opinion, this phase 3 trial does confirm that fixed-dose combination is well tolerated, has acceptable safety, and markedly improves PVR, fulfilling the guideline goal of controlling PAH more quickly.

Dr. Chin reports financial relationships with Altavant, Arena, Gossamer Bio, Janssen, Merck, ShouTi, and United Therapeutics. Dr. Goldberg reports financial relationships with Abbott, Respicardia/Zoll, and Viscardia. Dr. Bozkurt reports financial relationships with Abbott, Amgen, AstraZeneca, Boehringer Ingelheim, Cardurion, LivaNova, Relypsa, Renovacor, Sanofi-Aventis, and Vifor.

Three-year results from the Evolut trial seem to provide more reassurance on the use of transcatheter aortic valve replacement (TAVR) in low-surgical-risk patients.

The 3-year results show that low-surgical-risk patients undergoing aortic valve replacement continue to show lower rates of all-cause mortality and disabling stroke with TAVR, compared with surgery.

The rates of all-cause mortality or disabling stroke (the primary endpoint) at 3 years were 7.4% with TAVR and 10.4% with surgery.

Rates of new pacemaker implantation continued to be higher after TAVR and the frequency of new onset atrial fibrillation was more common after surgery.

“At 3 years, the rate of all-cause mortality or disabling stroke after TAVR with the Evolut valve compared very favorably to surgery. The absolute difference between treatment arms remained consistent with a 30% relative reduction in the hazard of death or disabling stroke, with a P value that just missed statistical significance,” said Evolut investigator John Forrest, MD, Yale University School of Medicine, New Haven, Conn.

“The Kaplan-Meier curves show what we’ve come to expect – an early separation of the curves – but what’s unique here, and seen for the first time, is that the early separation is maintained at year 1 and year 2, and between years 2 and 3 the curve didn’t start to come together, but, if anything, separated a little,” Dr. Forrest commented. 

“Both components of the primary endpoint – all cause mortality and disabling stroke – numerically favor TAVR. The separation of the curves for stroke are maintained, and if anything, we see a further slight separation of the curves as we go forward out to 3 years in terms of all-cause mortality,” he added.  

Dr. Forrest presented the 3-year results from the Evolut trial at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. They were simultaneously published online in the Journal of the American College of Cardiology.

Dr. Forrest also reported that TAVR patients continued to have better valve hemodynamics at 3 years and very low rates of valve thrombosis; moreover, rates of moderate or greater paravalvular regurgitation and paravalvular leak (factors that can affect valve durability) were also low, although mild paravalvular regurgitation was higher with TAVR.

“In these low-risk patients, the durability of the valve is going to be critically important,” Dr. Forrest commented. “The excellent valve performance and durable outcomes out to 3 years in low-risk patients affirms the role of TAVR in this population,” he concluded.

On how these results may affect clinical practice, Dr. Forrest said: “I think in the U.S. these results reaffirm what we are doing. It gives us confidence to continue treating low-risk patients and being comfortable with that.”

He added: “Outside the U.S., the guidelines are a little different. Maybe we should reconsider some of these guidelines based on these data.”

David Moliterno, MD, Gill Heart and Vascular Institute, Lexington, Ky., who is not involved in the TAVR studies, said: “The results provide a little more reassurance ... that will go a little way further.”

“Uncertainty remains regarding long-term durability of the transcatheter valve in low-risk patients who are generally younger and likely more active than higher-risk cohorts,” he added. “The current 3-year results provide more confidence as the outcome curves for death and disabling stroke are trending in the right direction for TAVR versus surgery.”

Dr. Moliterno pointed out that while rates of paravalvular regurgitation and permanent pacemaker placement are decreasing with newer generation Evolut devices and implantation techniques, he noted that according to the U.S. Social Security Administration, patients aged 74 years as enrolled in this low-risk cohort have an additional life expectancy of approximately 12 years. “So, we have more device durability (and coronary access feasibility) to prove.”

In his presentation, Dr. Forrest explained that TAVR is now approved in the United States for all patients with aortic stenosis regardless of surgical risk and has become the dominant form of aortic valve replacement. Current ACC/AHA guidelines recommend that heart teams utilize a shared decision-making process when discussing aortic valve replacement with patients aged 65-80 years. In younger, lower-risk patients, the faster recovery and short-term benefits after TAVR must be balanced with long-term durability; however, only limited intermediate and long-term data exist to guide such discussions in this patient population.

The Evolut Low Risk trial randomly assigned 1,414 patients in need of aortic valve replacement to TAVR with a self-expanding, supra-annular valve or surgery. Results at 1 and 2 years have shown a similar benefit in the primary endpoint of all-cause mortality/disabling stroke for the less invasive TAVR procedure.  

The current 3-year results suggest the benefit appears to be maintained out for another year. 

The main results show that the rate of death or disabling stroke was 7.4% in the TAVR group versus 10.4% in the surgery group, giving a hazard ratio of 0.70 (P = .051).

In the JACC paper, the authors report that the absolute difference between treatment arms for all-cause mortality or disabling stroke remained broadly consistent over time: –1.8% at year 1; –2.0% at year 2; and –2.9% at year 3.

Other key results on valve durability show that mild paravalvular regurgitation was increased in the TAVR group (20.3%) versus 2.5% with surgery. However, rates of moderate or greater paravalvular regurgitation for both groups were below 1% and not significantly different between groups.

Patients who underwent TAVR had significantly improved valve hemodynamics (mean gradient 9.1 mm Hg TAVR vs. 12.1 mm Hg surgery; P < .001) at 3 years.

However, pacemaker placement was much higher in the TAVR group (23.2%), compared with 9.1% in the surgery group.

On the other hand, the surgery group had a greater incidence of atrial fibrillation (40%) versus 13% with TAVR.

Quality-of-life results looked good in both groups.

“As we’ve come to expect, patients recover more quickly after TAVR, so at 30 days their quality of life is better than those who have undergone surgery,” Dr. Forrest commented. “But by 1 year, both groups are doing exceptionally well and, remarkably, here by 3 years both groups have greater than a 20-point increase in their KCCQ score, showing a very large improvement in quality of life.”

Discussant of these latest results at the ACC late-breaking trials session, James Hermiller, MD, St. Vincent Ascension Heart Center, Indianapolis, said: “This 3-year data continues to demonstrate that the gift of TAVR keeps giving.”

Noting that the divergence in the effect curves was primarily driven by mortality rather than stroke, he asked whether this was cardiac or noncardiac mortality that was reduced.

Dr. Forrest responded: “It was a fairly equal contribution – a little bit more cardiac death. We have to remember that although the average age in this study was 74, there were some patients over 80 who were still low-surgical-risk included so we are going to see noncardiac death as well.”

Dr. Hermiller drew attention to the high pacemaker rate in the TAVR group and asked how these patients fared in comparison to those who didn’t need a pacemaker.

Dr. Forrest replied: “I think it’s fair to say that putting in a pacemaker is not a benign procedure. Patients who got a pacemaker did slightly worse than those who didn’t get a pacemaker, so we need to try to drive that rate down.”

He added that the number of patients needing a pacemaker after TAVR has come down with new implantation techniques and new generation valves.

“We realize that using a cusp overlap technique can significantly reduce the need for a pacemaker, and we see from registry data that with the use of this new technique the need for a pacemaker has dropped down to 8%-9%, significantly less than seen in this study,” Dr. Forrest commented.    

Dr. Hermiller also asked about how TAVR affects future access for catheterization or percutaneous coronary intervention.  

Dr. Forrest noted that 24 patients in the TAVR group required PCI in first 3 years, and all the PCI procedures had been successful. He noted that operators reported the procedure to be easy or moderately easy in about 75%-80% of cases and difficult in about 20% of patients. “So, it is slightly more challenging to engage the coronaries and have to go through the frame, but it is very feasible.”

Dr. Forrest concluded that: “These results provide patients and heart teams important data to aid in the shared decision-making process.”

But he acknowledged that longer term data are still needed. “And the potential impact that hemodynamics, valve design, new pacemakers, and other secondary endpoints have on long-term outcomes will be important to follow in this group of low-risk patients.”

The Evolut Low Risk trial was funded by Medtronic. Dr. Forrest has received grant support/research contracts and consultant fees/honoraria/speakers bureau fees from Edwards Lifesciences and Medtronic.

A version of this article first appeared on Medscape.com.

Three-year results from the Evolut trial seem to provide more reassurance on the use of transcatheter aortic valve replacement (TAVR) in low-surgical-risk patients.

The 3-year results show that low-surgical-risk patients undergoing aortic valve replacement continue to show lower rates of all-cause mortality and disabling stroke with TAVR, compared with surgery.

The rates of all-cause mortality or disabling stroke (the primary endpoint) at 3 years were 7.4% with TAVR and 10.4% with surgery.

Rates of new pacemaker implantation continued to be higher after TAVR and the frequency of new onset atrial fibrillation was more common after surgery.

“At 3 years, the rate of all-cause mortality or disabling stroke after TAVR with the Evolut valve compared very favorably to surgery. The absolute difference between treatment arms remained consistent with a 30% relative reduction in the hazard of death or disabling stroke, with a P value that just missed statistical significance,” said Evolut investigator John Forrest, MD, Yale University School of Medicine, New Haven, Conn.

“The Kaplan-Meier curves show what we’ve come to expect – an early separation of the curves – but what’s unique here, and seen for the first time, is that the early separation is maintained at year 1 and year 2, and between years 2 and 3 the curve didn’t start to come together, but, if anything, separated a little,” Dr. Forrest commented. 

“Both components of the primary endpoint – all cause mortality and disabling stroke – numerically favor TAVR. The separation of the curves for stroke are maintained, and if anything, we see a further slight separation of the curves as we go forward out to 3 years in terms of all-cause mortality,” he added.  

Dr. Forrest presented the 3-year results from the Evolut trial at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. They were simultaneously published online in the Journal of the American College of Cardiology.

Dr. Forrest also reported that TAVR patients continued to have better valve hemodynamics at 3 years and very low rates of valve thrombosis; moreover, rates of moderate or greater paravalvular regurgitation and paravalvular leak (factors that can affect valve durability) were also low, although mild paravalvular regurgitation was higher with TAVR.

“In these low-risk patients, the durability of the valve is going to be critically important,” Dr. Forrest commented. “The excellent valve performance and durable outcomes out to 3 years in low-risk patients affirms the role of TAVR in this population,” he concluded.

On how these results may affect clinical practice, Dr. Forrest said: “I think in the U.S. these results reaffirm what we are doing. It gives us confidence to continue treating low-risk patients and being comfortable with that.”

He added: “Outside the U.S., the guidelines are a little different. Maybe we should reconsider some of these guidelines based on these data.”

David Moliterno, MD, Gill Heart and Vascular Institute, Lexington, Ky., who is not involved in the TAVR studies, said: “The results provide a little more reassurance ... that will go a little way further.”

“Uncertainty remains regarding long-term durability of the transcatheter valve in low-risk patients who are generally younger and likely more active than higher-risk cohorts,” he added. “The current 3-year results provide more confidence as the outcome curves for death and disabling stroke are trending in the right direction for TAVR versus surgery.”

Dr. Moliterno pointed out that while rates of paravalvular regurgitation and permanent pacemaker placement are decreasing with newer generation Evolut devices and implantation techniques, he noted that according to the U.S. Social Security Administration, patients aged 74 years as enrolled in this low-risk cohort have an additional life expectancy of approximately 12 years. “So, we have more device durability (and coronary access feasibility) to prove.”

In his presentation, Dr. Forrest explained that TAVR is now approved in the United States for all patients with aortic stenosis regardless of surgical risk and has become the dominant form of aortic valve replacement. Current ACC/AHA guidelines recommend that heart teams utilize a shared decision-making process when discussing aortic valve replacement with patients aged 65-80 years. In younger, lower-risk patients, the faster recovery and short-term benefits after TAVR must be balanced with long-term durability; however, only limited intermediate and long-term data exist to guide such discussions in this patient population.

The Evolut Low Risk trial randomly assigned 1,414 patients in need of aortic valve replacement to TAVR with a self-expanding, supra-annular valve or surgery. Results at 1 and 2 years have shown a similar benefit in the primary endpoint of all-cause mortality/disabling stroke for the less invasive TAVR procedure.  

The current 3-year results suggest the benefit appears to be maintained out for another year. 

The main results show that the rate of death or disabling stroke was 7.4% in the TAVR group versus 10.4% in the surgery group, giving a hazard ratio of 0.70 (P = .051).

In the JACC paper, the authors report that the absolute difference between treatment arms for all-cause mortality or disabling stroke remained broadly consistent over time: –1.8% at year 1; –2.0% at year 2; and –2.9% at year 3.

Other key results on valve durability show that mild paravalvular regurgitation was increased in the TAVR group (20.3%) versus 2.5% with surgery. However, rates of moderate or greater paravalvular regurgitation for both groups were below 1% and not significantly different between groups.

Patients who underwent TAVR had significantly improved valve hemodynamics (mean gradient 9.1 mm Hg TAVR vs. 12.1 mm Hg surgery; P < .001) at 3 years.

However, pacemaker placement was much higher in the TAVR group (23.2%), compared with 9.1% in the surgery group.

On the other hand, the surgery group had a greater incidence of atrial fibrillation (40%) versus 13% with TAVR.

Quality-of-life results looked good in both groups.

“As we’ve come to expect, patients recover more quickly after TAVR, so at 30 days their quality of life is better than those who have undergone surgery,” Dr. Forrest commented. “But by 1 year, both groups are doing exceptionally well and, remarkably, here by 3 years both groups have greater than a 20-point increase in their KCCQ score, showing a very large improvement in quality of life.”

Discussant of these latest results at the ACC late-breaking trials session, James Hermiller, MD, St. Vincent Ascension Heart Center, Indianapolis, said: “This 3-year data continues to demonstrate that the gift of TAVR keeps giving.”

Noting that the divergence in the effect curves was primarily driven by mortality rather than stroke, he asked whether this was cardiac or noncardiac mortality that was reduced.

Dr. Forrest responded: “It was a fairly equal contribution – a little bit more cardiac death. We have to remember that although the average age in this study was 74, there were some patients over 80 who were still low-surgical-risk included so we are going to see noncardiac death as well.”

Dr. Hermiller drew attention to the high pacemaker rate in the TAVR group and asked how these patients fared in comparison to those who didn’t need a pacemaker.

Dr. Forrest replied: “I think it’s fair to say that putting in a pacemaker is not a benign procedure. Patients who got a pacemaker did slightly worse than those who didn’t get a pacemaker, so we need to try to drive that rate down.”

He added that the number of patients needing a pacemaker after TAVR has come down with new implantation techniques and new generation valves.

“We realize that using a cusp overlap technique can significantly reduce the need for a pacemaker, and we see from registry data that with the use of this new technique the need for a pacemaker has dropped down to 8%-9%, significantly less than seen in this study,” Dr. Forrest commented.    

Dr. Hermiller also asked about how TAVR affects future access for catheterization or percutaneous coronary intervention.  

Dr. Forrest noted that 24 patients in the TAVR group required PCI in first 3 years, and all the PCI procedures had been successful. He noted that operators reported the procedure to be easy or moderately easy in about 75%-80% of cases and difficult in about 20% of patients. “So, it is slightly more challenging to engage the coronaries and have to go through the frame, but it is very feasible.”

Dr. Forrest concluded that: “These results provide patients and heart teams important data to aid in the shared decision-making process.”

But he acknowledged that longer term data are still needed. “And the potential impact that hemodynamics, valve design, new pacemakers, and other secondary endpoints have on long-term outcomes will be important to follow in this group of low-risk patients.”

The Evolut Low Risk trial was funded by Medtronic. Dr. Forrest has received grant support/research contracts and consultant fees/honoraria/speakers bureau fees from Edwards Lifesciences and Medtronic.

A version of this article first appeared on Medscape.com.

Three-year results from the Evolut trial seem to provide more reassurance on the use of transcatheter aortic valve replacement (TAVR) in low-surgical-risk patients.

The 3-year results show that low-surgical-risk patients undergoing aortic valve replacement continue to show lower rates of all-cause mortality and disabling stroke with TAVR, compared with surgery.

The rates of all-cause mortality or disabling stroke (the primary endpoint) at 3 years were 7.4% with TAVR and 10.4% with surgery.

Rates of new pacemaker implantation continued to be higher after TAVR and the frequency of new onset atrial fibrillation was more common after surgery.

“At 3 years, the rate of all-cause mortality or disabling stroke after TAVR with the Evolut valve compared very favorably to surgery. The absolute difference between treatment arms remained consistent with a 30% relative reduction in the hazard of death or disabling stroke, with a P value that just missed statistical significance,” said Evolut investigator John Forrest, MD, Yale University School of Medicine, New Haven, Conn.

“The Kaplan-Meier curves show what we’ve come to expect – an early separation of the curves – but what’s unique here, and seen for the first time, is that the early separation is maintained at year 1 and year 2, and between years 2 and 3 the curve didn’t start to come together, but, if anything, separated a little,” Dr. Forrest commented. 

“Both components of the primary endpoint – all cause mortality and disabling stroke – numerically favor TAVR. The separation of the curves for stroke are maintained, and if anything, we see a further slight separation of the curves as we go forward out to 3 years in terms of all-cause mortality,” he added.  

Dr. Forrest presented the 3-year results from the Evolut trial at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. They were simultaneously published online in the Journal of the American College of Cardiology.

Dr. Forrest also reported that TAVR patients continued to have better valve hemodynamics at 3 years and very low rates of valve thrombosis; moreover, rates of moderate or greater paravalvular regurgitation and paravalvular leak (factors that can affect valve durability) were also low, although mild paravalvular regurgitation was higher with TAVR.

“In these low-risk patients, the durability of the valve is going to be critically important,” Dr. Forrest commented. “The excellent valve performance and durable outcomes out to 3 years in low-risk patients affirms the role of TAVR in this population,” he concluded.

On how these results may affect clinical practice, Dr. Forrest said: “I think in the U.S. these results reaffirm what we are doing. It gives us confidence to continue treating low-risk patients and being comfortable with that.”

He added: “Outside the U.S., the guidelines are a little different. Maybe we should reconsider some of these guidelines based on these data.”

David Moliterno, MD, Gill Heart and Vascular Institute, Lexington, Ky., who is not involved in the TAVR studies, said: “The results provide a little more reassurance ... that will go a little way further.”

“Uncertainty remains regarding long-term durability of the transcatheter valve in low-risk patients who are generally younger and likely more active than higher-risk cohorts,” he added. “The current 3-year results provide more confidence as the outcome curves for death and disabling stroke are trending in the right direction for TAVR versus surgery.”

Dr. Moliterno pointed out that while rates of paravalvular regurgitation and permanent pacemaker placement are decreasing with newer generation Evolut devices and implantation techniques, he noted that according to the U.S. Social Security Administration, patients aged 74 years as enrolled in this low-risk cohort have an additional life expectancy of approximately 12 years. “So, we have more device durability (and coronary access feasibility) to prove.”

In his presentation, Dr. Forrest explained that TAVR is now approved in the United States for all patients with aortic stenosis regardless of surgical risk and has become the dominant form of aortic valve replacement. Current ACC/AHA guidelines recommend that heart teams utilize a shared decision-making process when discussing aortic valve replacement with patients aged 65-80 years. In younger, lower-risk patients, the faster recovery and short-term benefits after TAVR must be balanced with long-term durability; however, only limited intermediate and long-term data exist to guide such discussions in this patient population.

The Evolut Low Risk trial randomly assigned 1,414 patients in need of aortic valve replacement to TAVR with a self-expanding, supra-annular valve or surgery. Results at 1 and 2 years have shown a similar benefit in the primary endpoint of all-cause mortality/disabling stroke for the less invasive TAVR procedure.  

The current 3-year results suggest the benefit appears to be maintained out for another year. 

The main results show that the rate of death or disabling stroke was 7.4% in the TAVR group versus 10.4% in the surgery group, giving a hazard ratio of 0.70 (P = .051).

In the JACC paper, the authors report that the absolute difference between treatment arms for all-cause mortality or disabling stroke remained broadly consistent over time: –1.8% at year 1; –2.0% at year 2; and –2.9% at year 3.

Other key results on valve durability show that mild paravalvular regurgitation was increased in the TAVR group (20.3%) versus 2.5% with surgery. However, rates of moderate or greater paravalvular regurgitation for both groups were below 1% and not significantly different between groups.

Patients who underwent TAVR had significantly improved valve hemodynamics (mean gradient 9.1 mm Hg TAVR vs. 12.1 mm Hg surgery; P < .001) at 3 years.

However, pacemaker placement was much higher in the TAVR group (23.2%), compared with 9.1% in the surgery group.

On the other hand, the surgery group had a greater incidence of atrial fibrillation (40%) versus 13% with TAVR.

Quality-of-life results looked good in both groups.

“As we’ve come to expect, patients recover more quickly after TAVR, so at 30 days their quality of life is better than those who have undergone surgery,” Dr. Forrest commented. “But by 1 year, both groups are doing exceptionally well and, remarkably, here by 3 years both groups have greater than a 20-point increase in their KCCQ score, showing a very large improvement in quality of life.”

Discussant of these latest results at the ACC late-breaking trials session, James Hermiller, MD, St. Vincent Ascension Heart Center, Indianapolis, said: “This 3-year data continues to demonstrate that the gift of TAVR keeps giving.”

Noting that the divergence in the effect curves was primarily driven by mortality rather than stroke, he asked whether this was cardiac or noncardiac mortality that was reduced.

Dr. Forrest responded: “It was a fairly equal contribution – a little bit more cardiac death. We have to remember that although the average age in this study was 74, there were some patients over 80 who were still low-surgical-risk included so we are going to see noncardiac death as well.”

Dr. Hermiller drew attention to the high pacemaker rate in the TAVR group and asked how these patients fared in comparison to those who didn’t need a pacemaker.

Dr. Forrest replied: “I think it’s fair to say that putting in a pacemaker is not a benign procedure. Patients who got a pacemaker did slightly worse than those who didn’t get a pacemaker, so we need to try to drive that rate down.”

He added that the number of patients needing a pacemaker after TAVR has come down with new implantation techniques and new generation valves.

“We realize that using a cusp overlap technique can significantly reduce the need for a pacemaker, and we see from registry data that with the use of this new technique the need for a pacemaker has dropped down to 8%-9%, significantly less than seen in this study,” Dr. Forrest commented.    

Dr. Hermiller also asked about how TAVR affects future access for catheterization or percutaneous coronary intervention.  

Dr. Forrest noted that 24 patients in the TAVR group required PCI in first 3 years, and all the PCI procedures had been successful. He noted that operators reported the procedure to be easy or moderately easy in about 75%-80% of cases and difficult in about 20% of patients. “So, it is slightly more challenging to engage the coronaries and have to go through the frame, but it is very feasible.”

Dr. Forrest concluded that: “These results provide patients and heart teams important data to aid in the shared decision-making process.”

But he acknowledged that longer term data are still needed. “And the potential impact that hemodynamics, valve design, new pacemakers, and other secondary endpoints have on long-term outcomes will be important to follow in this group of low-risk patients.”

The Evolut Low Risk trial was funded by Medtronic. Dr. Forrest has received grant support/research contracts and consultant fees/honoraria/speakers bureau fees from Edwards Lifesciences and Medtronic.

A version of this article first appeared on Medscape.com.