Large-Bore Mechanical Thrombectomy Versus Catheter-Directed Thrombolysis in the Management of Intermediate-Risk Pulmonary Embolism: Primary Results of the PEERLESS Randomized Controlled Trial

There are a lack of randomized controlled trial data comparing outcomes of different catheter-based interventions for intermediate-risk pulmonary embolism.

PEERLESS is a prospective, multicenter, randomized controlled trial that enrolled 550 patients with intermediate-risk pulmonary embolism with right ventricular dilatation and additional clinical risk factors randomized 1:1 to treatment with large-bore mechanical thrombectomy (LBMT) or catheter-directed thrombolysis (CDT). The primary end point was a hierarchal win ratio composite of the following (assessed at the sooner of hospital discharge or 7 days after the procedure): (1) all-cause mortality, (2) intracranial hemorrhage, (3) major bleeding, (4) clinical deterioration and/or escalation to bailout, and (5) postprocedural intensive care unit admission and length of stay. Assessments at the 24-hour visit included respiratory rate, modified Medical Research Council dyspnea score, New York Heart Association classification, right ventricle/left ventricle ratio reduction, and right ventricular function. End points through 30 days included total hospital stay, all-cause readmission, and all-cause mortality.