What percentage of patients with tetralogy of Fallot (TOF) and pulmonary atresia survive into adulthood without surgical intervention?

From the Guidelines

Less than 20% of patients with tetralogy of Fallot (TOF) and pulmonary atresia survive into adulthood without surgical intervention. This severe cardiac malformation combines the four classic defects of TOF (ventricular septal defect, overriding aorta, right ventricular hypertrophy, and right ventricular outflow tract obstruction) with complete obstruction of the pulmonary valve, making it incompatible with long-term survival in most cases. According to the ESC guidelines for the management of grown-up congenital heart disease 1, patients with non-confluent PAs with adequate, but not excessive, pulmonary blood flow in infancy can survive into adulthood without surgery. However, this is a rare scenario and most patients with TOF and pulmonary atresia require surgical intervention to survive.

• Key factors that influence survival include the presence of alternative blood supply to the lungs through collateral vessels or a patent ductus arteriosus.
• Those who do survive typically develop severe cyanosis, exercise intolerance, polycythemia, and right heart failure.
• Without surgical correction, these patients face progressive hypoxemia, increased risk of paradoxical emboli, brain abscesses, and eventual right ventricular failure.
• The few who reach adulthood without intervention generally have unusually well-developed collateral circulation that provides adequate pulmonary blood flow, but even these patients experience significantly reduced quality of life and shortened life expectancy compared to those who receive appropriate surgical treatment, as noted in the guidelines 1.

From the Research

Survival of Patients with Tetralogy of Fallot and Pulmonary Atresia without Surgical Intervention

• The available studies do not provide a direct answer to the question of what percentage of patients with tetralogy of Fallot (TOF) and pulmonary atresia survive into adulthood without surgical intervention 2, 3, 4, 5, 6.
• However, it is noted that patients with TOF and pulmonary atresia who do not undergo early correction are at risk of developing multiorgan dysfunction due to chronic cyanosis, which can lead to high early mortality if surgical correction is delayed 2.
• A case report describes a mildly symptomatic 16-year-old boy with TOF and absent pulmonary valve who underwent successful primary repair, highlighting the rarity of survival without repair into later adolescence or adulthood 5.
• The studies suggest that surgical correction of TOF and pulmonary atresia can be achieved with low early mortality, but late mortality and the need for reoperation continue to affect the long-term well-being of these patients 3, 4, 6.
• The lack of data on patients who do not undergo surgical intervention makes it difficult to estimate the percentage of patients who survive into adulthood without surgery.

Key Findings

• Surgical correction of TOF and pulmonary atresia is associated with improved functional status and survival 2, 3, 4.
• Delayed surgical correction can lead to high early mortality due to multiorgan dysfunction caused by chronic cyanosis 2.
• The presence of major aortopulmonary collateral arteries is a risk factor for late mortality 4.
• Nakata index and Z-score can be used to assess the suitability of patients for complete repair 6.