Impact of mode of failure and end-organ dysfunction on the survival of adult Fontan patients undergoing cardiac transplantation

Objectives: Adults with failing Fontan circulation (FFC) represent a heterogeneous, high-risk group for cardiac transplantation with poor reported outcomes. We studied the impact of mode of Fontan failure (preserved versus impaired systolic ventricular function) and end-organ dysfunction on early survival in adults undergoing cardiac transplantation for FFC.

Methods: A single-centre, retrospective study of 26 adults (≥16 years) with FFC undergoing cardiac transplantation between 1990 and 2015. Patients were classified by the presence or absence of preserved systolic ventricular function (PVF). End-organ dysfunction was assessed by serum markers, including albumin, liver ultrasound and the presence of varices, ascites, splenomegaly and thrombocytopaenia (VAST score for portal hypertension).

Results: Thirty-day survival rate for the entire cohort was 69.2%, with 76.2% survival for the recent era. One-year Kaplan-Meier survival rate was 65.4%. Actuarial survival was poorer in those with PVF or heterotaxy (P = 0.01; log-rank test). Cox multivariable regression analysis confirmed PVF as an independent predictor for death (odds ratio, OR 5.38; confidence interval, CI 1.08-26.96; P = 0.04). In examining the PVF subset further, these patients had significantly higher VAST and liver ultrasound scores and lower serum albumin, compared with patients with impaired function. Patients with PVF and ≥moderate liver fibrosis on ultrasound or VAST score ≥2 accounted for two-thirds of the total mortality.

Conclusions: Favourable cardiac transplantation outcomes can be achieved in adults with failing Fontan circulation. Patients with PVF may represent a distinct subset with more perturbed failing Fontan physiology and higher cardiac transplant mortality. We continue, however, to evolve and refine our strategies and are optimistic concerning future improvement in outcomes even in those with PVF.