• Catheter-directed thrombolysis benefited patients with intermediate-high-risk acute pulmonary embolism.
• Thrombolysis plus anticoagulation greatly reduced grave outcomes vs. anticoagulation alone.

MUNICH — Compared with anticoagulation alone, catheter-directed thrombolysis plus anticoagulation greatly reduced grave outcomes in patients with intermediate-high-risk acute pulmonary embolism, researchers reported.

For the PRAGUE-26 trial, presented at the European Society of Cardiology Congress and simultaneously published in The New England Journal of Medicine, researchers randomly assigned 558 patients (median age, 64 years; 40.9% women) with intermediate-high–risk acute pulmonary embolism (PE) to catheter-directed thrombolysis with alteplase plus anticoagulation or anticoagulation alone.

Intermediate-high-risk acute PE was defined as hemodynamic stability, a simplified Pulmonary Embolism Severity Index score of 1 or more and right ventricular dysfunction plus an elevated level of cardiac troponin or natriuretic peptide, in accordance with ESC guidelines. The primary outcome was all-cause mortality, PE recurrence or cardiorespiratory decompensation or collapse at 7 days.

“Why did we do this study? Because I think we owe it to our patients with pulmonary embolism, [which] is common,” Viktor Kocka, MD, PhD, from the department of cardiology, University Hospital Královské Vinohrady and Charles University in Prague, said at a press conference. “In-hospital mortality is similar or higher than that for myocardial infarction, it ranges between 10% and 20%, and a large majority of patients in 2026 are treated exactly by the same methods — routine anticoagulation, and then systemic thrombolysis only if the patient crashes — as 30 years ago when I started my medical practice. So there is a big clinical need.”

The primary outcome occurred in 0.7% of the catheter-directed thrombolysis group compared with 6.8% of the standard care group (RR = 0.1; 95% CI, 0.02-0.44; P < .001; number needed to treat to prevent one event = 17), the researchers found.

The results were driven by cardiorespiratory decompensation or collapse, which occurred in 0.7% of the catheter-directed thrombolysis group and 5.4% of the standard care group (RR = 0.13; 95% CI, 0.03-0.57), Kocka said, noting that at 7 days there were no deaths in the catheter-directed thrombolysis group and four in the standard care group, and two cases of recurrent PE in the catheter-directed thrombolysis group compared with one in the standard care group.

There were no differences between the groups at 7 days in clinically relevant bleeding (thrombolysis group, 4.6%; standard care group, 5%; P = .85) or major bleeding (thrombolysis group, 1.4%; standard care group, 2.2%; P = .54), while two patients from the thrombolysis group and no patients from the standard care group had intracranial hemorrhage, according to the researchers.

“The key takeaway message is that we are going to have new pulmonary embolism guidelines in Europe in 2027, and I hope that these data together with the previously published data will change those guidelines and will completely change the paradigm of our treatment of pulmonary embolism,” Kocka said at the press conference.