Background: Nearly half of all patients with proximal deep vein thrombosis (DVT) will develop postthrombotic syndrome at 2 years. Small trials have shown that the combination of catheter-directed delivery of thrombolytics, along with active mechanical clot removal, may prevent the postthrombotic syndrome.
Study design: Randomized, controlled trial.
Setting: Fifty-six clinical centers throughout the United States.
Synopsis: A total of 692 patients with symptomatic proximal DVT were randomized to receive either pharmacomechanical thrombolysis followed by anticoagulation or solely anticoagulation consistent with published guidelines. The primary outcome measured was the development of postthrombotic syndrome between 6 and 24 months. Over the 24 months that these patients were followed, 157 of 336 patients (47%) in the pharmacomechanical thrombolysis group and 171 of 355 patients (48%) in the control group developed postthrombotic syndrome (risk ratio, 0.96; 95% confidence interval, 0.82-1.11; P = .56). This result was consistent across predetermined subgroups.
Importantly, major bleeding within 10 days was more frequent in the pharmacomechanical thrombolysis group occurring in 6 of 336 patients (1.7%) versus 1 of 335 patients (0.3%) in the control group (P = .049). There was no significant difference in either recurrent venous thromboembolism at 24 months (12% in treatment group vs. 8% in control; P = .09) or deaths.
Of the 80 patients that did not present for follow-up postthrombotic syndrome assessments, two-thirds were in the control group, potentially leading to an underestimation of the effect of the intervention.
Bottom line: Pharmacomechanical catheter-directed thrombolysis does not reduce postthrombotic syndrome in proximal DVT and leads to an increased risk of major bleeding.
Citation: Vedantham S et al. Pharmacomechanical catheter-directed thrombolysis for deep-vein thrombosis. N Engl J Med. 2017 Dec 7;377(23):2240-52.
Dr. Scaletta is a hospitalist at Denver Health Medical Center and an assistant professor of medicine at the University of Colorado at Denver, Aurora.