Pulmonary embolism (PE) is an important cause of morbidity and mortality with more than 100,000 US cases annually and as many as 25% of patients presenting with sudden death. Pulmonary embolism is associated with increased mortality rates for up to 3 months after the index PE event. Multiple studies and meta-analyses have evaluated the role of thrombolytic therapy in PE with largely discordant results.
Several recent trials have evaluated the role of thrombolytics in PE for the patients without definitive results, particularly for the end-point of mortality. Thus, this clinical investigation performed a meta-analysis of all randomized trials of thrombolytic therapy in PE. It aimed to ascertain associations of thrombolytic therapy with bleeding risk and potential mortality benefits, with special attention paid to the subpopulation of patients presenting with intermediate-risk PE.
Eligible studies were randomized clinical trials comparing thrombolytic therapy vs anticoagulant therapy in pulmonary embolism patients. Sixteen trials comprising 2115 individuals were identified. Eight trials comprising 1775 patients specified inclusion of patients with intermediate-risk pulmonary embolism.
**Main Outcomes and Measures**
The primary outcomes were all-cause mortality and major bleeding. Secondary outcomes were risk of recurrent embolism and intracranial hemorrhage (ICH). Peto odds ratio (OR) estimates and associated 95% CIs were calculated using a fixed-effects model.
Associations with lower mortality were derived largely from use of thrombolytics for patients with intermediate-risk PE in the contemporary era (2009-2014). In intermediate-risk pulmonary embolism trials, thrombolysis was associated with lower mortality and more major bleeding events.
In a subgroup analysis of patients older than 65 years, there was a nonsignificant association with lower mortality, however, there was an association with greater risk of major bleeds for the same subgroup.