Venous thromboembolism after acute stroke.

Abstract

To the Editor: The recent review by Kelly et al1 generally takes a balanced view of the evidence cited but surprisingly omits some very important evidence. There is good evidence from several sources that antiplatelet agents (most of the evidence comes from trials of aspirin) are effective and safe in preventing deep venous thrombosis (DVT) and pulmonary embolism (PE) in a wide variety of patients at high risk of venous thromboembolism.2 3 A systematic review of the randomized trials available up to 1994, including a total of approximately 9000 patients, showed that antiplatelet agents (chiefly aspirin) significantly reduced the risk of DVT by 39% and PE by 64%.2 3 Some clinicians were not persuaded by the evidence from the Antiplatelet Trialists’ meta-analysis, so a large-scale trial was established to confirm or refute these results. The Pulmonary Embolism Prevention (PEP) trial sought to evaluate the effects of low-dose aspirin in the prevention of pulmonary embolism and deep vein thrombosis in patients undergoing surgery for hip fracture.4 The trial randomized 13 356 patients to aspirin or placebo. Allocation to aspirin significantly reduced the odds of PE by 43% (95% CI 18 to 60) and symptomatic DVT by 29% (95% CI 3 to 48).4 The Cochrane review by Gubitz et al5 (not cited by Kelly) identified 8 trials of antiplatelet therapy in patients with acute ischemic stroke that reported effects on venous …