Thrombolysis Versus Anticoagulation for the Initial Treatment of Moderate Pulmonary Embolism: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND: Randomized trials and meta-analyses have reached conflicting conclusions regarding the risk benefit ratio of thrombolytic therapy or anticoagulant therapy in patients with moderate pulmonary embolism. To investigate the effect of initial thrombolysis and anticoagulant therapy in patients with moderate pulmonary embolism, we performed an updated meta-analysis. METHODS: We searched the MEDLINE, Embase, Cochrane Library, Wanfang, and CNKI databases for randomized controlled trials focusing on moderate pulmonary embolism. We then performed a meta-analysis of all randomized trials comparing thrombolytic therapy with heparin treatment in subjects with moderate pulmonary embolism. RESULTS: Fifteen trials involving 1,247 subjects were included. Compared with anticoagulation, thrombolytic therapy was associated with a significant reduction in recurrent pulmonary embolism or death (1.94% vs 5.87%, odds ratio (OR) of 0.37, 95% CI 0.21-0.66, P for heterogeneity = .49), a nonsignificant increase in major bleeding (3.57% vs 2.67%, OR 1.34, 95% CI 0.70-2.58), and a significant increase in non-major bleeding (12.78% vs 3.65%, OR 4.12, 95% CI 2.37-7.17). Thrombolysis was associated with a significant reduction in recurrent pulmonary embolism or death in trials that enrolled both foreign subjects (3.46% vs 7.76%, OR 0.45, 95% CI 0.23-0.86) and Chinese subjects (0% vs 3.72%, OR 0.18, 95% CI 0.05-0.73). With regard to moderate pulmonary embolism, comparison of thrombolysis and anticoagulation showed a nonsignificant heterogeneity between the 2 trial groups (P = .12). CONCLUSIONS: Both mortality and pulmonary embolism recurrence are decreased with thrombolysis compared with heparin treatment in patients with moderate pulmonary embolism. The risk of non-major bleeding is increased, but the risk of major bleeding is not.