Safety and Feasibility of On-the-Table Pharmacomechanical Lysis for Acute Intermediate-Risk Pulmonary Embolism: The RESCUE-II Study.

Background: Acute pulmonary embolism (PE) is a leading cause of morbidity and mortality. Pharmacomechanical lysis (PML) with the Bashir endovascular catheter has been shown to reduce the right ventricular/left ventricular (RV/LV) ratio in patients with intermediate-risk (IR) PE. Nevertheless, the original protocol required a 5-hour postprocedural infusion of recombinant tissue plasminogen activator (r-tPA) and intensive care unit monitoring.

Objectives: The RESCUE-II (Safety and Feasibility of On-The-Table Pharmacomechanical Lysis for Acute Intermediate-Risk Pulmonary Embolism) study aimed to evaluate the safety and efficacy of on-the-table PML using bolus-only r-tPA, without postprocedural infusion, in patients with IR-PE.

Methods: In this single-center, prospective study, symptomatic patients with IR-PE (computed tomographic-derived RV/LV ratio ≥0.9) were treated with bolus-only r-tPA via the Bashir catheter (4 mg per lung, 8 mg total for bilateral PE). The primary efficacy endpoint was the change in RV/LV ratio at 48 hours, and the primary safety endpoint was major bleeding within 72 hours.

Results: Nine patients were enrolled and successfully treated. The median procedure time was 39 ± 13.4 minutes. At 48 hours, the mean RV/LV ratio decreased from 1.66 ± 0.56 to 1.27 ± 0.41 (P = 0.0001), and pulmonary artery obstruction, measured by the Refined Modified Miller index, reduced by 29.2%. There were no major bleeding events. One patient had a minor access site hematoma, managed with manual compression.

Conclusions: On-the-table PML using the Bashir catheter effectively reduced RV/LV ratio and PA obstruction. The procedure was safe, with no major bleeding complications, and offers a rapid, cost-effective treatment option for patients with acute IR-PE.