Characteristics and Survival of Patients with the Total Artificial Heart Implanted for Indications Other Than Biventricular Failure

Abstract

Purpose Total heart replacement with the artificial heart (TAH) is an effective bridge to transplant for patients with primary biventricular heart failure (BiVHF). We sought to characterize our experience with the TAH in patients with alternate indications (ALT) other than BiVHF. Methods and Materials We conducted a single-center retrospective study of 66 patients who received the TAH from 2006-2012. The baseline characteristics of patients in each group are analyzed with a chi-squares and two-sample independent t-test. Survival to transplant is evaluated with a Cox regression and Kaplan-Meier analysis. Results 26 of the 66 patients (39%) received the TAH for ALT, which included: hypertrophic cardiomyopathy (n=2), refractory arrhythmias (n=8), acute shock (n=6), ventricular rupture (n=2), LVAD failure (n=3) and cardiac allograft failure (n=5). Though the ALT patients trended toward INTERMACS profile 1 (50% vs 35%, p= 0.2), we found no statistically significant difference in baseline characteristics or laboratory values between ALT vs BiVHF. There was no statistical difference in survival between the 2 groups by KM analysis (77% vs 93%, log rank test p=0.2) and Cox regression analysis (HR of BiVHF 0.42 [CI: 0.1, 1.7], p=0.2). Of the 6 patients in the ALT group that died, 2 were implanted for acute allograft rejection, 2 had refractory shock after myocardial infarction bridged from ECMO, 1 had LVAD failure and 1 was in refractory shock with acute heart failure. Conclusions The TAH is effective therapy for indications beyond BiVHF, although conditions such as cardiac allograft failure and refractory shock may be associated with higher risk. Variable BiVHF ALT p-value Male 80.8% 90% 0.3 Ischemic 23.1% 20% 0.8 Age (years) 48.8 48.7 0.8 BMI (kg/m²) 29.1 29.0 0.9 Hgb (g/dL) 10.9 10.4 0.4 Creatinine (mg/dL) 1.7 1.6 0.7 AST (IU/L) 148.2 494.2 0.2 Total bilirubin (mg/dL) 1.8 1.5 0.2 INR 1.4 1.5 0.5 Mean RA (mm Hg) 19.3 15.9 0.2 Mean PAP (mm Hg) 39.8 31.9 0.07 PCWP (mm Hg) 28.8 23.6 0.08 INTERMACS 1 35% 50% 0.2