Catheter Reperfusion Versus Anticoagulation in Intermediate-Risk Pulmonary Embolism: A Meta-Analysis

Background: The role of catheter-based reperfusion therapies in intermediate-risk pulmonary embolism (PE) remains less certain, particularly regarding comparative efficacy across lysis-based and mechanical thrombectomy approaches versus anticoagulation alone. Research Question: Do catheter-based reperfusion strategies improve clinical outcomes compared with anticoagulation alone in intermediate-risk PE, and do effects differ by reperfusion modality? Methods: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating catheter-directed reperfusion strategies plus anticoagulation versus anticoagulation alone in adults with intermediate-risk PE. PubMed, Embase, Cochrane Library, and ClinicalTrials.gov were searched from inception through May 2026. Outcomes included all-cause mortality, bleeding, hemodynamic decompensation, PE-related mortality, and trial-defined composite clinical outcomes. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were estimated using random-effects models; heterogeneity was assessed using the I 2 statistic. Subgroup analyses compared lysis-based (catheter-directed thrombolysis/ultrasound-assisted thrombolysis) versus mechanical thrombectomy approaches. Results: Five randomized controlled trials comprising 820 patients were included. There was no difference in all-cause mortality between catheter-based reperfusion and anticoagulation alone (RR 1.07; 95% CI 0.25-4.61), with no significant subgroup interaction between lysis-based and mechanical approaches (P-interaction=0.24). Trial-defined major bleeding was similar overall (RR 1.58; 95% CI 0.67-3.70) with no subgroup difference (P-interaction=0.80). PE-related mortality was also not significantly different (RR 1.62; 95% CI 0.25-10.72; P-interaction=0.38). In contrast, catheter-based reperfusion significantly reduced trial-defined composite adverse clinical outcomes (RR 0.38; 95% CI 0.21-0.68; p=0.001), with significant benefit observed in the lysis-based subgroup (RR 0.36; 95% CI 0.19-0.67; p=0.001) but not in the mechanical thrombectomy subgroup (P-interaction=0.62). Hemodynamic decompensation was also significantly reduced overall (RR 0.34; 95% CI 0.18-0.65; p=0.001), with a significant benefit in the lysis-based subgroup (RR 0.34; 95% CI 0.17-0.67; p=0.002) but not in the mechanical thrombectomy subgroup, with no evidence of subgroup difference (P-interaction=0.93). Conclusion: Catheter-based reperfusion in intermediate-risk PE does not reduce mortality or major bleeding compared with anticoagulation alone, but improves composite clinical outcomes and reduces hemodynamic decompensation, mainly driven by lysis-based therapy. Evidence for mechanical thrombectomy is limited to a single trial and remains inconclusive.