Marginal Improvement in Survival Post-Heart Transplantation in Patients With Prior Left Ventricular Assist Device: A Temporal Analysis of United Network of Organ Sharing Registry

Abstract

An increasing number of patients undergoing heart transplantation are being bridged with left ventricular assist devices (LVADs). Bridge-to-transplantation (BTT) LVAD has improved wait list survival remarkably. Historically, post-heart transplantation survival in BTT-LVAD patients, however, has remained inferior to that of primary heart transplantation. The authors hypothesized that in the modern era, the difference between post-heart transplantation survival in BTT-LVAD versus primary heart transplantation should be reduced. The objective of the present study was to determine whether there has been a change in survival after heart transplantation in patients with prior LVAD. The present study's cohort was compared with a historical cohort using the United Network of Organ Sharing (UNOS) database from 1995 to 2004.5 DESIGN: Retrospective observational analysis of data from the United Network of Organ Sharing database. Registry-based, observational, retrospective. Patients undergoing adult orthotopic heart transplantation, excluding redo transplantation and multiorgan transplantations. None. From the UNOS database, 22,065 patients who underwent heart transplantation between January 1, 2006, and December 31, 2016, were analyzed. Of these, 7,008 (31.76%) patients had prior LVAD (BTT-LVAD). Data analysis was performed with R software (Version 3.5.1) for Kaplan-Meier survival analysis and Cox proportional hazard ratio (HR) modeling to identify variables influencing survival. For patients with prior LVAD, the overall HR was 1.15 (95% confidence interval [CI] 1.07-1.24) for survival. An HR of 3.22 (95% CI 2.23-4.68) for death in patients who received extracorporeal membrane oxygenation post-transplantation and an HR of 0.72 (95% CI 0.58-0.90) for survival in patients whose procedures were performed in high-volume centers performing more than 35 transplantations per year were identified. Reduced survival in patients who received an LVAD before heart transplantation persists. However, there may have been a slight improvement in the HR for survival in the study cohort in the recent decade compared with the historical cohort from previous decades. It is intriguing that despite the paramount advances in both technology and clinical practice of LVAD, relatively minor survival benefit, if any, has occurred in post-heart transplantation for patients bridged with prior LVAD.