Surgical Intervention for Outflow Graft Obstruction in Patients With Magnetically Levitated Centrifugal-Flow Left Ventricular Assist Devices.

Abstract

Outflow graft obstruction (OGO) is an under-reported but severe complication after insertion of magnetically levitated centrifugal-flow left ventricular assist devices (LVADs). The optimal treatment and long-term outcomes have not been well-described. We report a retrospective single high-volume center's experience with surgical exploration for OGO from June 2019 to October 2023. Outflow graft obstruction was identified in 19 LVAD recipients from a total experience of 550 LVAD implants (3.3%). Median time of LVAD support to development of OGO was 32.5 months (interquartile range [IQR], 28-47.5). Low-flow alarms were the most common presentation, followed by dyspnea on exertion, and syncope. Computed tomography angiography (CTA) and echocardiography were the most common diagnostic modalities. Aortic valve opening with every beat and worsened mitral insufficiency were both more common at presentation compared to prior echocardiographic studies. Surgical excision of the bend relief (BR) and evacuation of proteinaceous material between the BR and the outflow graft immediately improved hemodynamics and LVAD function. There were no in-hospital mortalities, and all patients were discharged home after a median length of stay of 9 days (IQR, 10-21). All but four patients were alive at median follow-up 21 months. Thirteen of the 19 patients were readmitted a total of 50 times, none for recurrent OGO.