45 - Transposition of the Great Arteries

Abstract

Congenital heart defects account for 5% to 7% of congenital heart disease and affect 3 in 10,000 live births. They affect more males than females. In transposition of the great arteries (TGA), there are two parallel circulations that recycle oxygenated blood through the lungs and deoxygenated blood through the systemic circulation. Without prompt repair, death in the first year is almost universal. Most commonly, patients with TGA have normal systemic venous return, normal atrial situs, and normal atrioventricular connections. The aortic valve typically arises from the morphologic right ventricle, anteriorly and rightward from the pulmonic valve, which arises from the morphologic left ventricle. Approximately 50% of patients born with TGA have coexisting congenital anomalies, including ventricular septal defect, left ventricular outflow tract obstruction (i.e., subpulmonic stenosis), and coronary anomalies. Associated defects can increase the surgical risk and affect late outcomes after repair. This chapter focuses on adults with repaired TGAs.