Clinical Outcome of Late Survivors Following the Classic Fontan Procedure

Heart failure and multi-organ dysfunction develop insidiously in adults with a classic Fontan circulation. We evaluated late outcomes and risk factors for failing Fontan beyond 20 years after the classic Fontan procedure. Among 170 patients operated between 1978 and 1995, those surviving beyond 20 years without Fontan conversion were included. Clinical outcomes and risk factors were assessed. Sixty patients were included: tricuspid atresia in 37, double-inlet left ventricle in 14. Over 35.2 years' median follow-up, 13 (21.7%) died and 31 (51.7%) developed failing Fontan at a median of 30.8 years. Survival was lower with failing Fontan (70.2% vs. 95.2% at 35 years; P = .013) than those without. In multivariable analysis, double-inlet left ventricle (hazard ratio 2.42; P = .027) and ascites (hazard ratio 2.70; P = .007) were independent risk factors. At the last follow-up, the failing group had lower serum albumin (4.2 vs. 4.6 g/dL; P = .017) and higher N-terminal pro-B-type natriuretic peptide (774 vs. 404 pg/mL; P = .004); hepatic markers, total protein, and platelet count did not differ. After adjustment for the interval since diagnosis and exclusion of protein-losing enteropathy, only the natriuretic peptide association persisted. Peak oxygen uptake was also lower (P < .01). Late mortality and failing Fontan remained substantial beyond two decades. Double-inlet left ventricle and ascites were independent risk factors. Higher natriuretic peptide and reduced exercise capacity characterized the failing group, whereas lower albumin did not independently identify it. Regular assessment of these markers may aid surveillance.