Risk factors for early death in patients bridged to transplant with continuous-flow left ventricular assist devices

Background: Recent evidence suggests patients bridged to heart transplant (BTT) have equivalent outcomes as those undergoing conventional orthotopic heart transplantation (OHT). However, data on risk factors for early death in BTT patients are limited. Methods: We retrospectively reviewed the United Network for Organ Sharing database of all patients bridged to OHT with a HeartMate II from January 2005 to December 2010. The primary outcome was all-cause 90-day mortality. Additional postoperative outcomes were cerebrovascular accident and need for renal replacement therapy. Kaplan-Meier analysis assessed survival. Preoperative variables associated with 90-day death on univariate analysis (p < 0.2) were included in a multivariable Cox proportional hazards regression. Results: A HeartMate II was used to bridge 1,312 patients (average age, 52 ± 12 years) to OHT, most commonly for idiopathic cardiomyopathy (50.7%). During the study, 171 patients (13.0%) died. The unadjusted 90-day survival was 92.3%. The highest annual average center volume in this cohort, examining for BTT recipients only, was 28 BTT procedures yearly. Postoperative cerebrovascular accident occurred in 29 patients (2.2%), and 106 (8.3%) required renal replacement therapy. Cox regression revealed age, glomerular filtration rate, African American race, human leukocyte antigen mismatch, serum bilirubin, need for mechanical ventilation, donor age, and prolonged ischemia time were associated with 90-day death. Early survival was improved for patients who underwent OHT at high-volume centers (p = 0.01). Conclusions: This study examining risk factors for early death in patients bridged to OHT using HeartMate II mechanical assistance will aid in identifying patients best suited to benefit from this technology.