Does Survival on the Heart Transplant Waiting List Depend on the Underlying Heart Disease?

OBJECTIVES The aim of this study was to identify differences in survival on the basis of type of heart disease while awaiting orthotopic heart transplantation (OHT). BACKGROUND Patients with restrictive cardiomyopathy (RCM), congenital heart disease (CHD), or hypertrophic cardiomyopathy (HCM) may be at a disadvantage while awaiting OHT because they often are poor candidates for mechanical circulatory support and/or inotropes. METHODS The study included all adults in the Scientific Registry of Transplant Recipients database awaiting OHT from 2004 to 2014, and outcomes were evaluated on the basis of type of heart disease. The primary endpoint was time to all-cause mortality, censored at last patient follow-up and time of transplantation. Multivariate Cox proportional hazards modeling was performed to evaluate survival by type of cardiomyopathy. RESULTS There were 14,447 patients with DCM, 823 with RCM, 11,799 with ischemic cardiomyopathy (ICM), 602 with HCM, 964 with CHD, 584 with valvular disease, and 1,528 in the "other" category (including 1,216 for retransplantation). During median follow-up of 3.7 months, 4,943 patients died (1,253 women, 3,690 men). After adjusting for possible confounding variables including age, renal function, inotropes, mechanical ventilation, and mechanical circulatory support, the adjusted hazard ratios by diagnoses relative to DCM were 1.70 for RCM (95% confidence interval [CI]: 1.43 to 2.02), 1.10 for ICM (95% CI: 1.03 to 1.18), 1.23 for HCM (95% CI: 0.98 to 1.54), 1.30 for valvular disease (95% CI: 1.07 to 1.57), 1.37 for CHD (95% CI: 1.17 to 1.61), and 1.51 for "other" diagnoses (95% CI: 1.34 to 1.69). Sex was a significant modifier of mortality for ICM, RCM, and "other" diagnoses (p < 0.05 for interaction). CONCLUSIONS In the United States, patients with RCM, CHD, or prior heart transplantation had a higher risk for death while awaiting OHT than patients with DCM, ICM, HCM, or valvular heart disease.