Effect of left ventricular dysfunction on utilization of donor hearts

Abstract

Background: In this study we investigated modern, non-utilization rates of potential cardiac donors with left ventricular dysfunction (LVD) to clarify this phenomenon's magnitude and the impact of recent studies suggesting these organs can be safely transplanted.

Methods: Using the United Network for Organ Sharing transplant database, we reviewed all donors evaluated between January 1, 2007 and June 30, 2014. Exclusion criteria included lack of consent and age <13 or >59 years. The number of hearts not transplanted due to non-cardiac causes, structural disease, "other" (previous cardiac surgery, donation after cardiac death, etc.) and isolated LVD was determined and a covariates-adjusted Poisson regression model with robust standard errors was developed to estimate non-utilization relative risk (RR) with 95% confidence interval (CI) for LVD. Heart disposition for potential donor hearts was determined separately for 2 previous eras (1990 to 1999 and 2000 to 2006), and trends were evaluated.

Results: There were 60,789 donors assessed. Of the 44,829 organs meeting the inclusion criteria, 15,654 (34.92%) were transplanted and 29,175 (65.08%) were not. Of the non-utilized hearts, 15,512 (34.60%) were declined for non-cardiac reasons, 1,051 (2.34%) for structural disease, 4,073 (9.09%) for "other" and 8,539 (19.05%) exclusively for LVD. Of this last category, 4,950 (11.04%) lacked documented evidence of LVD. Covariates-adjusted RR for non-utilization showed that, for every 10% increase in LV ejection fraction, the risk of non-utilization decreased by 20% (RR = 0.80, 95% CI 0.79 to 0.81). Analysis of era-effect demonstrated significantly decreased overall utilization of donor hearts, with increases in the number of hearts not transplanted across all categories over time (p < 0.001).

Conclusions: Roughly 20% of potential cardiac donors are excluded due to LVD. This figure has not been impacted by recent studies indicating that these hearts may be used safely. More complete data are required to understand why 11.04% of hearts that met inclusion criteria were refused for "poor function" without documented evidence.

Keywords: donor heart dysfunction; donor heart utilization; heart transplantation.