Scientific Publications Database

Article Title: Residual pulmonary embolism as a predictor for recurrence after a first unprovoked episode: Results from the REVERSE cohort study
Authors: Wan, Tony; Rodger, Marc; Zeng, Wanzhen; Robin, Philippe; Righini, Marc; Kovacs, Michael J.; Tan, Melanie; Carrier, Marc; Kahn, Susan R.; Wells, Philip S.; Anderson, David R.; Chagnon, Isabelle; Solymoss, Susan; Crowther, Mark; White, Richard H.; Vickars, Linda; Bazarjani, Sadri; Le Gal, Gregoire
Journal: THROMBOSIS RESEARCH Volume 162
Date of Publication:2018
Abstract:
Background: The optimal duration of oral anticoagulant therapy after a first, unprovoked venous thromboembolism is controversial due to tightly balanced risks and benefits of indefinite anticoagulation. Risk stratification tools may assist in decision making.Objectives: We sought to determine the relationship between residual pulmonary embolism assessed by baseline ventilation-perfusion scan after completion of 5-7 months of oral anticoagulant therapy and the risk of recurrent venous thromboembolism in patients with the first episode of unprovoked pulmonary embolism.Methods: We conducted a multicentre prospective cohort study of participants with a first, unprovoked venous thromboembolism enrolled after the completion of 5-7 months of oral anticoagulation therapy. The participants completed a mean 18-month follow-up. Participants with pulmonary embolism had baseline ventilation-perfusion scan before discontinuation of oral anticoagulant therapy and the percentage of vascular obstruction on baseline ventilation-perfusion scan was determined. During follow-up after discontinuation of oral anticoagulant therapy, all episodes of suspected recurrent venous thromboembolism were independently adjudicated with reference to baseline imaging.Measurements and main results: During follow-up, 24 of 239 (10.0%) participants with an index event of isolated pulmonary embolism or pulmonary embolism associated with deep vein thrombosis and central assessment of percentage of vascular obstruction on baseline ventilation-perfusion scan had confirmed recurrent venous thromboembolism. As compared to participants with no residual pulmonary embolism on baseline ventilation-perfusion scan, the hazard ratio for recurrent venous thromboembolism was 2.0 (95% CI 0.5-7.3) for participants with percentage of vascular obstruction of 0.1%-4.9%, 2.1 (95% CI 0.5-7.8) for participants with percentage vascular obstruction of 5.0%-9.9% and 5.3 (95% CI 1.8-15.4) for participants with percentage vascular obstruction greater than or equal to 10%.Conclusions: Residual pulmonary embolism assessed by pulmonary vascular obstruction on baseline ventilation-perfusion performed after 5-7 months of oral anticoagulant therapy for the first episode of unprovoked pulmonary embolism was associated with a statistically significant higher risk of subsequent recurrent venous thromboembolism. Percentage of pulmonary vascular obstruction assessment by ventilation-perfusion scans maybe a useful tool to help guide the duration of oral anticoagulant therapy after a first unprovoked pulmonary embolism.