Fontan‐Related Lymphatic Complications: Incidence, Risk Factors, and Impact on Extracardiac Outcomes and Morbidity

Background Patients born with single ventricle anatomy palliated with the Fontan procedure are at risk of lymphatic complications (LC), including plastic bronchitis, protein losing enteropathy, and ascites. The mechanism of LC, associated risk factors, and impact on end organ dysfunction and mortality are not well understood. Methods We performed a single‐center, retrospective, cross‐sectional cohort study of patients with Fontan circulation seen at our center between 2009 and 2022. Univariate comparisons were completed comparing those with and without LC. Results A total of 314 Fontan patients were included with a mean age of 20.2±10.7 years. Of those patients, 83 (26.4%) had at least 1 LC, including ascites (21.4%), protein losing enteropathy (11.8%), and plastic bronchitis (2.9%). Patients with LC were older (23.5±12.6 versus 19.1±9.8 years, P =0.001) and had their Fontan operation at an older age (5.5 with LC versus 4.0 years without LC, P <0.001). The presence of LC was associated with renal dysfunction ( P =0.004), thromboembolism ( P =0.01), and arrhythmia ( P <0.001). LC were also associated with higher mean Fontan pressures on catheterization (14.7±3.8 with LC versus 12.8±3.7 mm Hg without LC, P =0.003). Fontan patients with LC had higher rates of transplantation (25.3% versus 2.2%, P <0.001) and death (18.1% with LC versus 4.3% without LC, P <0.001). Conclusions Fontan‐related lymphatic complications develop in 1 out of 4 patients by 20 years of age, and they are associated with older age, renal dysfunction, thromboembolism, and arrhythmia. Patients with LC have higher rates of transplantation and death. Our findings indicate that elevated central venous pressure, rather than systolic cardiac or atrioventricular valve function, is associated with these complications.