Peritoneal dialysis after complex congenital cardiac surgery was introduced to a group of neonates and infants (n = 756; age, 0 to 1 year) between May 1993 and December 2005. Indications of peritoneal dialysis were determined as well as methods, prolonged dialysis, and its outcomes. Demographic characteristics, preoperative risk factors, intraoperative variables, and postoperative complications were compared in 756 cases with ages below 1 year. All cases underwent ultrafiltration during the perioperative stage. One hundred eighty-six cases (24.6% of total) required peritoneal dialysis. The cardiac pathology was transposition of great arteries in 133 cases, tetralogy of Fallot in 37, aorticopulmonary window associated with interrupted aortic arch in 4 and total anomalous pulmonary venous return in 5, and other complex pathology in 7 cases. Prolonged peritoneal dialysis was usually required in infants with low weight, with episodes of pulmonary hypertensive crisis (p < 0.05), and with preoperative renal dysfunction. No major complication was observed related to the peritoneal dialysis catheter. Of 186 patients, 23 (12.3%) had acute renal failure, and 4 of them died (2.15% of all patients underwent operation, 17.3% of those with acute renal failure). It has been demonstrated that the combination of peritoneal dialysis with perioperative ultrafiltration application was effective in providing the required postoperative negative fluid balance in especially complex congenital heart cases and affected survival positively.