Clinicians’ Opinion on the ATTRACT Trial—Results of an International Survey

Objective: Acute deep venous thrombosis (DVT) can be complicated by post-thrombotic syndrome, which is associated with significant morbidity and health care costs. Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) was the largest and most controversial randomized controlled trial evaluating the use of pharmacomechanical catheter-directed thrombolysis for the prevention of post-thrombotic syndrome after acute DVT. This study aimed to evaluate clinicians’ opinion on the ATTRACT trial and its impact on clinical practice. Methods: An online survey consisting of 10 core multiple choice items and a maximum of 5 follow-up open-ended questions was delivered to vascular surgeons, interventional radiologists, hematologists, and interventional cardiologists affiliated with 10 international societies between April 23 and July 1, 2019. Clinicians’ views on the main limitations of the ATTRACT trial, its impact on patient selection for thrombolysis, and the need for a new trial were evaluated. Results: Of 15,650 contacted clinicians, 451 (3%) completed the survey, with 74% being vascular surgeons, 24% interventional radiologists, 2% hematologists, and 0.2% interventional cardiologists. The majority of respondents (79%) were aware of the results of the ATTRACT trial before completing the survey and routinely performed pharmacomechanical catheter-directed thrombolysis in their centers (70%). Only 20% of clinicians considered ATTRACT to be a well-designed and well-performed trial. The inclusion of femoropopliteal DVT was reported as the main limitation of the trial by 55% of respondents. Despite half of the participating clinicians reporting no change in their clinical practice, an equal number of clinicians (14%) were encouraged and discouraged from treating iliofemoral DVT. More than half of the respondents thought that the use of pharmacomechanical catheter-directed thrombolysis would be defensible in a court of law despite the increased risk of bleeding reported in the study. Nearly two-thirds of participating clinicians recommended performing a trial limited to iliofemoral DVT, with a follow-up period of 5 years, quality of life as the primary outcome measure, and standardization of the thrombolysis protocol across the trial sites. Conclusions: ATTRACT, owing to significant methodologic issues, failed to provide the long-awaited indisputable evidence on the use of pharmacomechanical catheter-directed thrombolysis. A new trial is needed to guide clinical practice.