In patients with intermediate-high–risk acute pulmonary embolism, catheter-directed thrombolysis with alteplase plus anticoagulation significantly reduced the 7-day risk of death, recurrent pulmonary embolism, or cardiorespiratory decompensation or collapse compared with anticoagulation alone, without a significant increase in clinically relevant or major bleeding. In this Czech multicenter, open-label, randomized trial, 558 patients were randomly assigned in a 1:1 ratio to receive catheter-directed alteplase thrombolysis plus anticoagulation (280 patients) or anticoagulation alone (278 patients). Eligible patients had acute pulmonary embolism with hemodynamic stability, a simplified Pulmonary Embolism Severity Index score of at least 1, right ventricular dysfunction, and elevated cardiac troponin or natriuretic peptide levels, identifying a population at intermediate-high risk of clinical deterioration. The median age was 64 years, and 40.9% of participants were female. The primary composite outcome occurred in 2 patients (0.7%) in the thrombolysis group and 19 patients (6.8%) in the standard-care group, corresponding to a relative risk of 0.10, with the difference driven mainly by a lower incidence of cardiorespiratory decompensation or collapse among patients receiving thrombolysis. By day 7, clinically relevant bleeding occurred in 13 patients (4.6%) in the thrombolysis group and 14 patients (5.0%) in the standard-care group, while major bleeding occurred in 4 patients (1.4%) and 6 patients (2.2%), respectively, with neither difference reaching statistical significance. Intracranial hemorrhage occurred in 2 patients (0.7%) receiving catheter-directed thrombolysis and in no patients receiving standard care. Within 30 days, one patient in the thrombolysis group died, whereas four patients in the standard-care group died within 7 days. Overall, these findings suggest that catheter-directed alteplase thrombolysis added to anticoagulation can substantially reduce early serious clinical deterioration in patients with intermediate-high–risk pulmonary embolism compared with anticoagulation alone, while maintaining similar overall rates of clinically relevant and major bleeding. Source: https://www.nejm.org/
