Ten-year outcomes of Fontan conversion in Australia and New Zealand demonstrate the superiority of a strategy of early conversion

Abstract

OBJECTIVE: To investigate the benefits of a strategy of early Fontan conversion. METHODS: Using the Australia and New Zealand Fontan Registry, retrospective analysis of their long-term follow-up data was performed. RESULTS: Between 1990 and 2014, a total of 39 patients underwent surgical conversion in 6 centres at a median age of 23.8 years (IQR: 19.3-28.2), 18.7 ± 5.0 years post-Fontan. One centre tended to perform conversion earlier: Interval since first documented arrhythmia 2.9 ± 4.0 vs 4.0 ± 4.2 years, average NYHA Class 2 ± 0.4 vs 3 ± 0.9 (P = 0.008), mean number of preop anti-arrhythmics 1 ± 0.4 vs 2 ± 0.6 (P = 0.05). Two patients underwent conversion to an extracardiac conduit only, while 36 had concomitant right atrial cryoablation, of which 16 also had pacemaker implantation. Nine patients suffered major cardiac-related complications (7 low output syndrome, 3 ECMO, 3 acute renal failure, one stroke) (2/17 from the early conversion centre and 7/22 of the others; P = 0.14). Four patients died in hospital (10.3%) and 4 late after a median of 0.9 years [95% confidence interval (CI): 0.5-1] after conversion. An additional 2 patients needed transplantation at 1 and 8.8 years after conversion, respectively. The 10-year freedom from heart transplantation was 86% (95% CI: 51-97%). Outcomes from the centre with an early conversion strategy were significantly better: 8-year freedom from death or heart transplantation was 86% (95% CI: 53-96) vs 51% (95% CI: 22-74; log-rank P = 0.007). Eight additional patients required pacemaker implantation and 5 had arrhythmia recurrence. CONCLUSIONS: Fontan conversion is associated with lasting survival outcomes up to 10 years after conversion. A strategy of surgical conversion at earlier stage of failure may be associated with better survival free from transplantation.