Risk Stratification in Heart Transplantation According to Donor and Recipient Risk Factors

Objectives: The aim of this study was to categorize 1-year survival after heart transplantation according to donor and recipient characteristics following a novel risk assessment tool.

Methods: We retrospectively collected donor and recipient-specific data sets of all heart transplantations performed in adults at our center between April 2009 and August 2018. Specific donor and recipient characteristics build up an effective risk score value ranging between 0 and 46. Transplanted patients were categorized according to calculated scores below 9, between 9 and 15, as well as beyond 15 into low, intermediate and high-risk groups, according to a recent UNOS database analysis.

Results: A total of 648 heart transplantations were analyzed. The majority of heart transplantations (n = 428) were performed with a risk score < 8, while 177 and 43 transplants reached a risk score between 9 and 15 as well as >15, respectively. Validating the risk score model, the 1-year survival probabilities in our center were 80.8, 70.8, and 57.4% in the three groups, reflecting a differentiation into low, intermediate and high-risk categories, respectively.

Conclusions: Novel risk assessment tools including donor and recipient specific characteristics are valid and help to facilitate cardiac allocation. Better matching will help to improve outcomes in cardiac transplantation. It remains to be discussed, why published UNOS data show an approximately 10% superior outcome in all three risk categories.