Importance  Cyanotic congenital heart diseases, which occur in approximately 0.2% of live births in the United States, have high mortality rates if untreated, but survival to adulthood is common with current surgical interventions.

Observations  Approximately 80% of all cyanotic congenital heart diseases are caused by tetralogy of Fallot (TOF), D-loop transposition of the great arteries (TGA), and congenital heart disease with single-ventricle circulation. Survivors of cyanotic congenital heart diseases benefit from multidisciplinary care including pediatric and adult cardiologists, congenital cardiac surgeons, and electrophysiologists. Ninety percent of patients with TOF survive more than 30 years after surgery to close the ventricular septal defect and repair the right ventricular outflow tract. Nearly all adults with repaired TOF develop right ventricular volume overload due to pulmonary regurgitation, and atrial tachycardias and atrial fibrillation occur in approximately 20% to 45% of patients by age 45 years. For D-loop TGA, which involves the aorta arising from the right ventricle and the pulmonary artery arising from the left ventricle, arterial switch procedures result in survival rates of 93% to 97% to age 30 years. After atrial switch operation, 30% to 50% of patients develop moderate or severe right ventricle dysfunction by age 25 years; atrial tachycardia occurs in 48% to 63% of patients at 32 to 40 years postsurgery, and sinus node dysfunction is common. Sudden cardiac death occurs at a mean age of 30 to 35 years (SD, 6.4 years) in up to 15% of adults who have undergone an atrial switch operation. Infants born with a single ventricle that supplies both systemic and pulmonary circulation are most often treated with staged open-heart surgical interventions, typically performed during a period from neonatal age to 6 years of age, culminating in the Fontan procedure, which connects the inferior and superior vena cava to the pulmonary arteries, allowing deoxygenated blood to flow to the lungs without a pumping ventricle. Survival rates for children who undergo the Fontan procedure are 50% to 80% at age 40 to 50 years, although these patients may develop New York Heart Association functional class III or IV (0.35% per person-year) and have increased risk of early death or heart transplant requirement (0.36% per person-year).

Conclusions and Relevance  With surgical intervention, survival to adulthood is common among patients with TOF, D-loop TGA, and single ventricle. However, these survivors of cyanotic congenital heart diseases are at risk of valve dysfunction, arrhythmias, heart failure, and premature death. Optimal care involves multidisciplinary management including pediatric and adult cardiologists, congenital cardiac surgeons, and electrophysiologists.