Promotion of Growth of True Pulmonary Arteries as a First Step in Staged Repair of Pulmonary Atresia, Ventricular Septal Defect and Major Aorto-Pulmonary Collateral Arteries

Background: Construction of a central shunt by connection of hypoplastic true pulmonary arteries to the ascending aorta (AO) can be performed as a first step in staged repair of pulmonary atresia with ventricular septal defect and major aorto-pulmonary collateral arteries (PA-VSD-MAPCAs) intended to promote growth and development of the central pulmonary arteries. Methods: To determine early and intermediate-term growth of true pulmonary arteries after their connection to the AO as a first step in staged repair of PA-VSD-MAPCAs, we reviewed all angiographic studies and CT imaging of patients, treated in our tertiary referral center in the last 26 years (1991 until 2017) for PAVSD-MAPCAs with such a shunt. Results: A total of 13 patients (6 male) underwent direct end-to-side connection of the true pulmonary artery with the AO.). The absolute median size of both PAs showed statistically significant absolute growth over time. The absolute LPA growth was estimated to be 0.013 mm/day (p < 0.001). The absolute RPA growth was estimated to be 0.010 mm/day (p = 0.001). In total 9/13 (69%) reached total repair and 4 were considered not suitable for final repair. Conclusions: Creation of a central shunt by connection of true pulmonary arteries to the AO promotes their growth in patients with PA-VSD-MAPCAs, particular the LPA, although not reaching normal size. Patients with pulmonary atresia, and diminutive pulmonary arteries are a high-risk group, with a lower complete repair rate compared to those with better sized PAs. Alternative techniques or interventions should be explored in these patients to augment the size of the pulmonary arteries.