Abstract 12043: Transplant Benefit Associated with Increasing Risk of Wait-list Mortality in Patients Listed for Heart Transplantation in the United States
The sickest patients among those listed for a heart transplant (HT) are also at higher risk of post-transplant mortality making it difficult to determine which patients may benefit most from HT. We hypothesized that transplant benefit, defined as percent reduction in risk of 90-day mortality on receiving HT close to listing increases as a patient's risk of wait-list mortality increases.
Methods: We analyzed all patients ≥ 18 years old listed for first HT in the US between 01/07 and 09/10. We developed risk-prediction models for 90-day wait-list mortality (or removal due to deterioration) using variables at listing and 90-day post-HT mortality using variables at HT. We applied each patient’s listing variables to the risk-models to predict risks of wait-list and post-HT mortality. We estimated HT benefit in patients stratified by risk of wait-list mortality. A secondary analysis estimated HT benefit based on risk-prediction of 1-yr post-HT mortality.
Results: Of 9687 patients in the study cohort, 6.4% reached the wait-list end-point (5.7% died, 0.7% removed due to worsening) within 90 days. Of 6118 HT recipients, 5.7% died within 90 days and 9.8% within 1 yr. The risk of 90-day wait-list mortality increased progressively (2.0% to 20.1%) from the 1st to the 10th risk-decile. The risk of 90-day post-HT mortality increased from 2.9% to 12.0% in the corresponding risk-strata. Transplant benefit was negative for the first 4 risk-deciles (post-HT mortality higher than wait-list mortality), increased from 1.4% in the 5th decile to 3.6% in the 9th decile, increased further to 5.1% for patients in the 91st-96th percentile and to 15.0% in the top 4% of risk (wait-list mortality risk 31.8 %, post-HT mortality risk 16.8%). Transplant benefit computed using risk of 1-yr post-HT mortality also demonstrated higher benefit in the highest risk-deciles of wait-list mortality.
Conclusions: The risk of 90-day wait-list morality varies by more than 10-fold among patients listed for HT in the US. While transplant benefit generally increases with increasing risk of wait-list mortality, there is no apparent benefit in many candidates at the lower end of the risk-spectrum. Considering transplant benefit in allocation of donor hearts may improve overall outcomes in patients listed for HT.
- © 2012 by American Heart Association, Inc.