Background: This study examined whether institutional volume impacts outcomes after orthotopic heart transplantation (OHT) utilizing marginal donors.
Methods: Adult patients undergoing OHT with the use of marginal donors between 2000 and 2010 were identified in the United Network for Organ Sharing database. A previously derived and validated donor risk score (range, 1 to 15) was used to define marginal donors as those in the 90th percentile of risk (score≥7). Patients were stratified into equal-size tertiles based on overall institutional OHT volume. Posttransplant outcomes were compared between these center cohorts.
Results: A total of 3,176 OHTs utilizing marginal donors were identified. In Cox regression analysis, recipients undergoing OHT at low-volume centers were at significantly increased risk of 30-day (hazard ratio 1.82 [1.31 to 2.54], p<0.001), 1-year (hazard ratio 1.40 [1.14 to 1.73], p=0.002), and 5-year posttransplant mortality (hazard ratio 1.29 [1.10 to 1.52], p=0.02). These findings persisted after adjusting for recipient risk, differences in donor risk score, and year of transplantation (each p<0.05). In Kaplan-Meier analysis, there was a similar trend of decreasing 1-year survival with decreasing center volume: high (86.0%), intermediate (85.7%), and low (81.2%; log rank p=0.003). Drug-treated rejection within the first post-OHT year was more common in low-volume versus high-volume centers (34.3% versus 24.2%, p<0.001). At an overall mean follow-up of 3.4±2.9 years, low-volume centers also had higher incidences of death due to malignancy (2.8% versus 1.3%, p=0.01) or infection (6.2% versus 4.1%, p=0.02).
Conclusions: Consolidating the use of marginal donors to higher volume centers may be prudent in improving post-OHT outcomes in this higher risk patient subset.
Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.