Outcome of patients with cyanotic congenital heart disease undergoing a second systemic-to-pulmonary artery shunt

Background. Multiple systemic-to-pulmonary artery shunts often represent a deviation from the initial management strategy for cyanotic congenital heart disease. This study analysed the outcome in patients undergoing a second shunt. Methods. Between 1965 and 1998, 80 patients required a second shunt. Patient age ranged from 11 days to 11.2 years at the initial shunt, and 4 months to 25.6 years at the second shunt. The interval between shunts ranged from 11 days to 19.6 years. Results. The patient survival rates at 1, 6, 12, 60 and 120 months following the second shunt were 95.0 ± 2.4%, 92.5 ± 3.0%, 87.4 ± 3.7%. 82.4 ± 4.5% and 74.8 ± 5.8%, respectively. Although excess pulmonary flow was not encountered after the second shunt, mode and incidence of morbidity were otherwise similar to the first one. Between 9 months and 7.5 years after the second shunt, 24 patients underwent successful definitive repair. Multivariable analysis identified pulmonary atresia (p = 0.027) and a short (< 1 year) interval between the two shunts (p = 0.034) as the independent risk factors for long-term shunt failure. Single ventricle physiology (p = 0.002) and a central approach for the second shunt (p = 0.016) were independent risk factors for lack of application, or failure of intracardiac definitive repair. Conclusions. A significant limitation in longevity and quality of life is common in patients requiring a second shunt, especially those associated with pulmonary atresia, the single ventricle physiology heart, or ungraftably hypoplastic contralateral branch pulmonary artery to the first shunt. Since excess pulmonary blood flow leading to congenital heart failure and/or ventricular diastolic dysfunction is unlikely, all patients who preclude definitive repair due to decreased pulmonary blood flow even after the first shunt should be shunted again.