PB0939 - A Multicenter Study Evaluating the Effect of Timing of Mechanical Thrombectomy in Improvement of Right Ventricular Function for Intermediate Risk Pulmonary Embolism

Background: Acute pulmonary embolism (PE) remains associated with significant mortality. Patients with signs of right ventricular (RV) dysfunction are at a high risk of adverse events. Mechanical thrombectomy reduces RV strain and is often performed in intermediate-risk PE. The optimal timing of the procedure is uncertain.

Aims: We aimed to assess the influence of timing of mechanical thrombectomy on right ventricular function in patients with intermediate-risk PE.

Methods: A multicenter retrospective study including patients presenting between 7/2020 and 7/2023 was performed including adults presenting with an intermediate-risk PE who were treated with mechanical thrombectomy. Patients with high risk PE upon presentation were excluded. We compared outcomes between patients who had a percutaneous thrombectomy within 12 hours of diagnosis (early treatment; ET) to those receiving intervention after 12 hours (delayed treatment, DT). Echocardiographic findings of right ventricular (RV) function and size were categorized as: normal, mild, mild-moderate, moderate, moderate to severe and severely abnormal. Our primary outcome was change in right ventricular size and function assessed by echocardiogram pre and post intervention.

Results: 114 patients (53.5% male, 61± 13 years old) were included. Of these, 67 (54%) were in the ET group and 47(38%) in the DT group. Presenting characteristics and other baseline demographics (table 1), vital signs, and echocardiographic parameters were similar between groups. Pre and post echocardiographic data was available for 79 patients. Patients in the ET group had a greater improvement in right ventricular function (p=0.028) and size (p=0.048) when compared to those in the DT group (Fig). In hospital mortality was 4.4%. Other secondary outcomes including intubation rate, vasopressor or inotrope use was comparable between groups (table).

Conclusion(s): When performed for intermediate-risk PE ET is associated with greater improvement in right ventricular size and function compared to DT.