Objective: To determine the clinical outcomes and factors influencing the results of late Fontan completion in functional single ventricle patients.

Material and Methods: The authors retrospectively analyzed data in functional single ventricle patients that underwent late Fontan completion (age more than four-year-old) between January 2007 and December 2017.

Results: The extracardiac conduit Fontan procedure was performed in thirty-six patients over four years old (median age 10 years). The early mortality rate was 11% and the overall mortality was 16%. According to the Cox regression analysis, pulmonary artery pressure greater than 15 mmHg was an unfavorable factor for hospital death. Other morbidities included persistent pleural effusion (44%), chylothorax (2.78%), early atrial tachycardia (5.56%), early graft thrombosis (5.56%), and late graft thrombosis (2.78%).

Conclusion: Late extracardiac conduit Fontan completion yielded acceptable outcomes. The authors found pulmonary artery pressure greater than 15 mmHg to be a risk factor for early mortality. Prevalence of postoperative persistent pleural effusion was higher in older patients, while rates of other complications did not differ from other age groups.

Keywords: Fontan operation, Late Fontan operation, Single ventricle, Functional single ventricle, Univentricular heart