Mitral Valve Anomalies in Transposition of the Great Arteries

Among 1,590 transposition of the great arteries {S, D, D} patients undergoing biventricular repair (1990–2020), 52 (3.3 percent) had abnormal mitral valves (MV)—mainly anterior clefts (88 percent) and subvalvular anomalies (60 percent). Most underwent an arterial switch; survival was 88.3 percent at 20 years. Ten patients underwent concomitant mitral procedures and none needed reoperation, while six others required late surgery for mitral regurgitation or left ventricular outflow tract obstruction. Freedom from late MV surgery was 82.8 percent at 20 years.