Midline unifocalization for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries

Richard D. Mainwaring


Background: Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA/VSD/MAPCAs) is a relatively rare and extremely heterogeneous form of congenital heart disease. Despite vast improvements in the surgical management of this disease, there is still an ongoing controversy regarding the optimal treatment. The purpose of this chapter is to summarize the surgical algorithm used at Stanford University with a special focus on midline unifocalization.
Methods: We have an experience with well over 300 patients undergoing primary surgical treatment of PA/VSD/MAPCAs. There were three pathways employed to accommodate the various forms of this heart defect. The dominant pathway is midline unifocalization, which was utilized in 80% of all patients. Less frequently employed strategies included creation of an aortopulmonary window (15%), and other approaches (5%).
Results: For the patients who underwent a midline unifocalization, 85% had a single-stage complete repair while 15% had a unifocalization and shunt. The operative mortality was 1.5% for the single-stage complete repair group vs. 8% for the unifocalization/shunt group. Ultimately, 97% of the midline unifocalization patients were repaired. However, the mean right ventricle to aortic pressure ratio was lower in patients who had a single-stage complete repair compared with an initial unifocalization/shunt (0.36±0.09 vs. 0.42±0.07).
Conclusions: The surgical treatment of PA/VSD/MAPCAs is made more complicated due to heterogeneity of MAPCA and pulmonary artery anatomy. The algorithm utilized at Stanford takes into account the anatomic heterogeneity and the results demonstrate that a high percentage of patients achieve full repair.