Protein-losing enteropathy following Fontan completion: A 30-year national cohort study in Sweden

OBJECTIVE: To characterize patients with protein-losing enteropathy (PLE) diagnosed before age 18 years within a nationwide Swedish Fontan cohort. METHODS: Surgical records and medical charts were reviewed for all patients born after January 1, 1993, who underwent Fontan completion before January 1, 2021. RESULTS: Among 573 reviewed patients, 28 (4.8%) developed PLE. The median time to onset of PLE after Fontan was 1.5 years (interquartile range, 0.5-5.5 years). Right ventricular morphology was associated with PLE (odds ratio, 2.3; 95% confidence interval, 1.04-5.0). Twenty-three patients (82%) received PLE-directed therapies, including pulmonary vasodilators (n = 17; 61%), subcutaneous heparin (n = 14; 50%), and/or long-term corticosteroids (n = 13; 46%). Eleven patients (39%) underwent a total of 18 catheter interventions, including 1 fenestration and 1 lymphatic intervention. Three pacemaker procedures were performed after a PLE diagnosis. Eight patients underwent heart transplant (26%). Patients with an early onset of PLE (<2 years from Fontan completion) frequently had a history of pulmonary venous congestion. Five-year overall survival was 88%, and 5-year transplant-free survival was 79%. CONCLUSIONS: PLE remains a serious complication following Fontan, with notable mortality. Patients with right ventricular morphology of the systemic ventricle had a higher risk of PLE. Previous pulmonary venous congestion was common when PLE was diagnosed early after Fontan. Catheter-based interventions were frequently used to optimize hemodynamics; lymphatic interventions are likely to become more common. In therapy-refractory patients, heart transplantation remains an option.