Abstract 16893: Thrombotic Events During Extended Microaxial Mechanical Circulatory Support for Cardiogenic Shock

Abstract

Background: Percutaneous ventricular assist devices (VAD) are used in ~1/3 of patients (pts) with cardiogenic shock (CS). A percutaneous microaxial intracardiac VAD can offer hemodynamic support weighed against a risk of vascular complications. However, few studies have addressed the incidence of thrombotic complications, particularly in pts who require extended mechanical circulatory support (MCS). Methods: We conducted an observational cohort study to quantify the risk of thrombotic events during MCS in pts managed with a microaxial VAD for CS or mixed shock from 2015-2020 in a quaternary referral center. All consecutive pts were captured in a prospective registry of MCS and retrospectively reviewed for potentially device-related thrombotic events by 2 physician adjudicators. All pts received systemic anticoagulation with unfractionated heparin and/or bivalirudin. Results: The study included 106 pts (72% male, mean age 59.8). Peripheral artery disease, and a significant smoking history were present in 12% and 44% of cases respectively. The duration of microaxial VAD use was 5.3 days on average and >7 days in 25%. A concurrent microaxial VAD and other MCS were used in 28% of cases. Thrombotic/ischemic events were observed in 24.5% and were subcategorized into limb ischemia with visualized thrombus (n=6), limb ischemia without visualized thrombus (n=6), systemic embolism (n=6), intraventricular thrombus (n=2), device thrombus (n=6), and device dysfunction (n=3). Three pts had more than one complication. Moderate to severe thrombocytopenia (<100mcg/dL) was observed in 78% of pts. In-hospital mortality was 51% and was not higher in pts with thrombotic events (p=0.14). Conclusion: Thrombotic events are common with a microaxial intracardiac VAD with an observed rate that was higher than previously reported. Larger studies of all-comers with MCS for CS are needed to better define the rate of MCS-associated complications.