Center volume and post-transplant survival among adults with congenital heart disease

Abstract

Background: The number of adult congenital heart disease (ACHD) patients requiring heart transplantation (HT) continues to grow, and if they survive the first year after transplant, their long-term survival is at least equivalent to non-ACHD patients. The 1-year survival of ACHD patients with HT remains lower than non-ACHD patients. We evaluated the affect of transplant center volume on 1-year survival of ACHD patients. We analyzed United Network of Organ Sharing patients (age ≥18 years) who underwent their first orthotopic HT between January 1, 2000, and December 31, 2015, to assess the association between transplant center volume and 1-year survival of ACHD patients.

Results: We identified 827 ACHD patients at 113 centers who underwent HT during the study period. The average age of the recipients and donors was 36 ± 13 years (60% men and 84% Caucasian) and 28 ± 11 (63% men and 66% Caucasian), respectively. Of the ACHD patients undergoing HT, 27% (n = 60) were done at low-volume centers, 30% (n = 10) were reported at high-volume centers, and the remaining (n = 43) were at medium-volume centers. A total of 96 patients died within 30 days, including 37 (16.7%) at low-volume, 37 (10.2%) at medium-volume, and 22 (9.0%) at high-volume centers (p = 0.019). The average unadjusted Kaplan-Meier 30-day survival at low-volume centers was 83% ± 2%, which was significantly lower than medium-volume (90% ± 1%) and high-volume (91% ± 2%) centers (log-rank p < 0.05). Within 1 year, 154 patients had died, including 56 (36.4%) at low-volume, 60 (38.9%) at medium-volume, and 38 (24.7%) at high-volume centers (p = 0.011). Average unadjusted Kaplan-Meier 1-year survival at low-volume centers was 75% ± 3%, which was significantly lower than medium-volume (83% ± 2%) and high-volume (84% ± 2%) centers (log-rank p < 0.05).

Conclusions: The 30-day and 1-year survival of ACHD patients undergoing HT is partly influenced by overall transplant center volume and, potentially, volume of ACHD HTs, with low-volume centers performing poorly relative to medium-volume and high-volume centers. The role of peri-operative care and multidisciplinary management in improving survival at low-volume centers required further investigations.

Keywords: ACHD; UNOS; cardiac; congenital; outcomes; transplant.