Aortic Root Thrombosis in Patients with HeartMate 3 Left Ventricular Assist Device Support

Background Aortic root thrombus (ART) formation is a complication of continuous flow left ventricular assist device (LVAD) therapy. However, the incidence and related complications of ART in HeartMate 3 (HM3) patients remains unknown. Methods Patients who underwent HM3 implantation from November 2014 through August 2020 at a quaternary academic medical center were included. Demographics and outcomes were abstracted from the medical record. Echocardiograms and contrast-enhanced CT studies were reviewed to identify patients who developed ART and/or moderate or greater aortic insufficiency (AI) on HM3 support. Results The study cohort included 197 HM3 patients with a median post-implant follow-up of 17.5 months. Nineteen patients (9.6%) developed ART during HM3 support, and 15 patients (7.6%) developed moderate or greater AI. Baseline age, gender, race, implantation strategy, and INTERMACS classification were similar between the ART and no-ART groups. ART was associated with an increased risk of death, stroke, or AV intervention (subhazard ratio [SHR] 3.60 [95% CI 1.71-7.56]; p=0.001) and moderate or greater AI (SHR 11.1 [CI 3.60-34.1]; p<0.001) but was not associated with a statistically significantly increased risk of death or stroke on HM3 support (2.12 [0.86-5.22]; p=0.10). Of the 19 patients with ART, 6 (31.6%) developed moderate or greater AI, necessitating more frequent AV interventions (ART: 5 AV interventions [3 surgical repairs, 1 surgical replacement, 1 transcatheter replacement; 26.3%]; no-ART: 0). Conclusion Nearly 10% of HM3 patients developed ART during device support. ART was associated with increased risk of a composite endpoint of death, stroke, or AV intervention as well as moderate or greater AI.