Failure to rescue: obesity increases the risk of mortality following early graft failure in heart transplantation in UNOS database patients

Abstract

Objectives Early graft failure is a devastating post-operative complication following heart transplant. Institutional studies have modelled donor and recipient risk factors predictive of graft failure. To date, no studies have assessed specific recipient profiles associated with mortality after recipients suffer from early graft failure. The objective of this study was to identify this recipient profile. Methods We performed a retrospective review of patients in the United Network for Organ Sharing Database undergoing heart transplant from August 2000—September 2019. Early graft failure was defined as graft dysfunction at 24 hours post heart-transplant. Primary outcome was 90-day mortality. To isolate recipient characteristics associated with mortality, we performed univariate analysis on 24 recipient characteristics adjusted for high-risk donor characteristics (ischaemic time, donor age, race mismatch, BUN/Cr ratio) predictive of 1-year mortality (p < 0.2). We then performed backwards stepwise multivariable regression adjusted for identified donor characteristics to determine recipient characteristics associated with mortality after early graft failure (p < 0.05). Results We identified 302 patients diagnosed with post-transplant early graft failure. Among these patients, mortality was 82% within 90 days of transplantation. Adjusted univariate analysis identified 7 factors associated with mortality. Adjusted backwards stepwise multivariable regression identified BMI > 30 as predictive of mortality at 90 days after early graft failure. Conclusions Patients who develop early graft failure after heart transplant are at high risk for mortality. Careful discussion regarding transplant candidacy and risk is warranted in obese patients. Additionally, minimizing donor factors associated with graft dysfunction is critical during pre-operative planning in these recipients.

Heart Transplantation

“…There are several predisposing factors responsible for this particular complication reflected in the RADIAL score, and they are right atrial pressure > 20 mmHg, donor age > 30 years, recipient age > 60 years, graft ischemia time > 4 h. Others are pre-operative LVAD use, female gender [85,86], obesity [87], and diabetes [88]. When donor risk factors are categorized, they are brain death, use of intravenous inotropes, age, and dysfunction of another donor graft.…”