510 - Large-Bore Mechanical Thrombectomy versus Catheter-Directed Thrombolysis for Intermediate-Risk Pulmonary Embolism: A Single-Center Retrospective Analysis

Monday, April 13, 2026

12:10 PM - 1:10 PM ET

Poster Presenter(s)

JP

Jeremy F. Palacio, BS

Medical Student
Saint Louis University School of Medicine, United States

Author/Co-author(s)

AC

Arianna D. Carfora, BS

Medical Student
Saint Louis University, United States
CP

Connor Parrish, BS

Medical Student
St. Louis University School of Medicine, United States
AP

Ameya Pathak, BS

Medical Student
Saint Louis University Department of Radiology, United States
BC

Brady Chrisler, BS

Medical Student
Saint Louis University Department of Radiology, United States
Karan B. Singh, MD (he/him/his)

Integrated Vascular & Interventional Radiology Resident
SSM Health Saint Louis University, United States
GM

Garry Morel, MD

Pulmonary and Critical Care Fellow
Saint Louis University Division of Pulmonary, Critical Care and Sleep Medicine, United States
JK

Jerome Kao, MD

Associate professor, interventional radiology
Saint Louis University Department of Vascular & Interventional Radiology, United States
AM

Ali Malik, MD

Assistant Professor
Saint Louis University School of Medicine, United States
AS

Afsheen Sherwani, MD

Assistant professor
Saint Louis University Department of Vascular and Interventional Radiology, United States
AN

Aravind Narayan Mohandas, MD

Assistant professor
Saint Louis University Department of Vascular and Interventional Radiology, United States
XP

Xavier R. Packianathan, MD, MBBS

Associate Professor
SSM Health Saint Louis University Hospital, Department of Vascular & Interventional Radiology, United States
RS

Radu Serban, MD

Assistant professor
SSM Health Saint Louis University Hospital, Department of Vascular & Interventional Radiology, United States
Millie Liao, DO, MS

Assistant Professor
Saint Louis University School of Medicine, United States
KV

Kirubahara Vaheesan, MD

Physician
Saint Louis University, United States
Keith Pereira, MD, DABR, RPVI, ABWM, FSIR

Associate Professor -Tenured
Saint Louis University School of Medicine, United States

Purpose: To compare the effects and outcomes of large-bore mechanical thrombectomy (LBMT) and catheter-directed thrombolysis (CDT) in patients with intermediate-risk pulmonary embolism (PE), and to place these real-world findings in context with prior randomized trial data.

Materials and Methods: This IRB-approved retrospective study included consecutive patients with intermediate-risk PE treated with LBMT or CDT at a single tertiary center between January 2018 and December 2024. High-risk PE was excluded. Treatment strategy was determined at physician discretion. Baseline demographics, comorbidities, and Pulmonary Embolism Severity Index (PESI) scores were collected. Primary safety endpoints were all-cause in-hospital mortality, PE-associated mortality, and major bleeding (International Society on Thrombosis and Haemostasis [ISTH] criteria). Secondary outcomes included ICU stay, hospital stay, and 30-day readmission. Group comparisons were performed using Fisher’s exact test for categorical variables and appropriate tests for continuous variables.

Results: A total of 170 patients met criteria for intermediate-risk PE (LBMT n=113; CDT n=57). Baseline characteristics, including PESI scores and right ventricular strain, were similar between groups. All-cause in-hospital mortality occurred in 9 of 113 patients (6.7%) treated with LBMT and 7 of 57 patients (12.3%) treated with CDT (p=0.41). PE-associated mortality was 5 patients (4.4%) in the LBMT group and 7 patients (12.3%) in the CDT group (p=0.11). Major bleeding, defined by ISTH criteria, occurred in 10 patients (8.8%) with LBMT and 6 patients (10.5%) with CDT (p=0.78). Mean ICU stay was 5.1 ± 7.7 days for LBMT and 4.3 ± 6.2 days for CDT (p=0.53), while mean total hospital stay was 9.5 ± 9.3 and 8.3 ± 6.8 days, respectively (p=0.39). Thirty-day readmission occurred in 15 of 113 patients (13.3%) in the LBMT group compared with 5 of 57 patients (8.8%) in the CDT group (p=0.46).

Conclusion: In this single-center, real-world cohort of intermediate-risk PE, outcomes with LBMT and CDT were broadly similar, with no significant differences in all-cause mortality, PE-associated mortality, or major bleeding. While PEERLESS’ superiority signal was driven by clinical deterioration and ICU admission—endpoints not captured in our dataset—PE-associated mortality and major bleeding were similar between LBMT and CDT in our cohort. These findings suggest comparable real-world outcomes across the two approaches and highlight the value of observational data in contextualizing RCT results.