Primary Fontan operation in adults: Challenges and early outcomes in adults at a tertiary cardiac centre in India.

BackgroundThe Fontan operation is the definitive palliation for single-ventricle physiology. In low- and middle-income countries, delayed diagnosis and limited paediatric cardiac services often result in adults presenting for primary Fontan rather than staged completion.MethodsAdults (≥18 years) undergoing extracardiac or lateral-tunnel Fontan between January 2021 and June 2025 were retrospectively reviewed. Variables included demographics, conduit and fenestration, cardiopulmonary bypass and cross-clamp times, re-exploration, extubation time, intensive care unit (ICU) stay, pulmonary-artery pressure, atrioventricular valve regurgitation, pleural effusion >14 days, arrhythmia and survival.ResultsTwenty-four adults (median age 20.5 years (interquartile range 19-22); 17 males (71%)) underwent primary Fontan: 18 (75%) extracardiac and 6 (25%) lateral tunnel. Fenestration was created in 14 (58%). Mean pulmonary-artery pressure increased from 12.6 ± 3.2 to 13.7 ± 3.5 mmHg (p = .12). Systemic oxygen saturation improved significantly from 79 ± 4% to 92.8 ± 3.1% (p < .001). Atrioventricular-valve regurgitation decreased significantly (p = .03), and New York Heart Association (NYHA) I-II class increased from 25% to 88% (p < .001). Pleural effusion >14 days occurred in nine (38%) and arrhythmia in three (13%) patients. Kaplan-Meier survival was 100% at 2 years and 95.8% at 3 years (95% confidence interval [83-100]).ConclusionsPrimary Fontan beyond childhood can be performed safely in adults with favourable haemodynamics, achieving excellent early survival and functional improvement. Standardised technique and vigilant postoperative care are central to recovery in low- and middle-income country settings.