Long-term outcomes of patients with primary graft dysfunction after cardiac transplantation

OBJECTIVES: The International Society of Heart and Lung Transplantation (ISHLT) criteria for primary graft dysfunction (PGD) after cardiac transplantation have been shown to stratify patient outcomes up to 1 year after transplantation, but scarce data are available regarding outcomes beyond the 1st year. We sought to characterize survival of patients with PGD following cardiac transplantation beyond the 1st year. METHODS: A retrospective review of consecutive patients undergoing isolated cardiac transplantation at a single centre between 2012 and 2015 was performed. Patients were diagnosed with none, mild, moderate or severe PGD by the ISHLT criteria. Survival was ascertained from the United Network for Organ Sharing database and chart review. Kaplan-Meier curves were plotted to compare survival. The hazard ratio for mortality associated with PGD severity was estimated using Cox-proportional hazards modelling, with a pre-specified conditional survival analysis at 90 days. RESULTS: A total of 257 consecutive patients underwent cardiac transplantation during the study period, of whom 73 (28%) met ISHLT criteria for PGD: 43 (17%) mild, 12 (5%) moderate and 18 (7%) severe. Patients with moderate or severe PGD had decreased survival up to 5 years after transplantation (log-rank P < 0.001). Landmark analyses demonstrated that patients with moderate or severe PGD were at increased risk of mortality during the first 90-days after transplantation as compared to those with none or mild PGD [hazard ratio (95% confidence interval) 18.9 (7.1-50.5); P < 0.001], but this hazard did not persist beyond 90-days in survivors (P = 0.64). CONCLUSIONS: A diagnosis of moderate or severe PGD is associated with increased mortality up to 5 years after cardiac transplantation. However, patients with moderate or severe PGD who survive to post-transplantation day 90 are no longer at increased risk for mortality as compared to those with none or mild PGD.