Thrombolysis for pulmonary embolism: A network meta-analysis

Background: Thrombolysis is an adjunct therapy in the management of pulmonary embolism. Several different thrombolytic agents are available. A recent shortage of alteplase led us to consider the relative merits of different agents. Methods: We performed a systematic review of thrombolytic agents for pulmonary embolism. Studies comparing any thrombolytic agent with placebo, usual care or another thrombolytic agent were included. Both a standard pairwise analysis and a network meta-analyses (using a Bayesian framework) were performed. Results: 28 studies were identified. In the pairwise analysis, thrombolysis did not show any benefit in mortality when compared with placebo (OR 0.69, 95% CI 0.43 to 1.1, 17 trials, 2220 participants) but it did cause an increase in serious bleeding events (OR 2.57, 95% CI 1.33 to 4.94, 14 trials, 2028 participants). The network analysis did not show superiority of any one thrombolytic agent over any other or over placebo for the outcome of mortality. tenecteplase was associated with significantly more bleeding than placebo. Conclusion: No thrombolytic performs significantly better than placebo in pulmonary embolism. Thrombolytic agents, particularly tenecteplase, are associated with serious bleeding.