Abstract 14817: Influence of Timing of Mechanical Thrombectomy in Treatment of Intermediate-Risk Pulmonary Embolism

Abstract

Background: Acute pulmonary embolism (PE) is associated with significant morality. Patients with signs of right ventricular (RV) dysfunction are at a high risk of adverse events. Mechanical thrombectomy reduces RV strain and therefore is often performed in intermediate-risk PE. The optimal timing of the procedure is uncertain. We aimed to assess the influence of timing of mechanical thrombectomy on outcomes in patients with intermediate-risk PE. Methods: A single-center, retrospective study collected patient data between 7/2020 and 1/2023. Adults presenting with an intermediate-risk PE who were treated with mechanical thrombectomy were included. Patients with high risk PE were excluded. We compared patient outcomes between individuals receiving intervention within 12 hours of diagnosis (early treatment; ET) to those receiving intervention after 12 hours of diagnosis (delayed treatment, DT). Our primary outcome was change in pulmonary artery pressures. Secondary outcomes included length of stay, intubation rates, vasopressor need and mortality. Results: 69 patients (52% male) were included for analysis. Of these, 37 were included in the ET group and 32 in the DT group. Presenting WHO class was higher in the ET group. Other baseline demographics, presenting vital signs, and echocardiographic parameters were similar between groups (Table). Patients in the ET group had a greater reduction in their pulmonary artery systolic pressure (PASP) after intervention compared to the DT group (-14.8 mm Hg vs. -8.3 mm Hg, p = 0.05; Fig). There were no differences in mortality, intubation rate, vasopressor or inotrope use between groups. There was no significant difference in overall hospital length of stay (LOS), though there was a trend towards shorter ICU LOS in the ET group (1.92 d vs. 4.2 d, p = 0.056). Conclusions: When performed for intermediate-risk PE ET is associated with greater reductions in PASP compared to DT.