Increased sensitivity to ischemic interval of donor hearts with diminished left ventricular function.

Background: Previous studies have demonstrated that carefully selected donor hearts (DHs) with poor left ventricular ejection fraction (EF) may be transplanted with long-term survival equivalent to hearts with normal function. The purpose of this study is to facilitate their selection.

Methods: Using the United Network for Organ Sharing database, we reviewed all adult heart transplants between January 2000 and March 2016. Regression models were developed to estimate hazard ratios with 95% confidence intervals of post-transplant 1-year mortality and failure of EF to recover at 1 year for DHs with EF ≥50%, EF 40%-49.9%, and EF 30%-30.9%.

Results: During the study period, 31,979 DHs were transplanted. Compared with DHs with left ventricular ejection fraction ≥50%, DHs with reduced EF were younger and had slightly lower body mass index. There were no differences in the mechanism of death between groups and no differences in recipient characteristics, except for a higher incidence of African American recipients of hearts with an EF of 40%-49.9%. Of the variables analyzed, only a 1-hour increase in ischemia time had different hazard ratios for 1-year mortality between groups, with increasing hazard as EF diminished. It was also the only variable that predicted failure of recovery of normal EF and that was in the lowest EF group.

Conclusions: The impact of DH traits associated with adverse outcomes after heart transplantation that we studied are similar between DHs with EF <50% and those with EF ≥50%. However, limiting ischemic time may be even more important for DHs with diminished left ventricular function, particularly at the low end of the EF spectrum.