A total of 118 patients were studied, 73% with a single right ventricle. At diagnosis, 37 patients (31%) had mild, 5 (4%) had mild to moderate, and 4 (3%) had ≥ moderate atrioventricular valve regurgitation. Moderate or greater valve regurgitation was associated with mortality (HR 5.51, 95% CI 1.24-24.61, p = 0.025), and all four patients with ≥ moderate valve regurgitation died. However, valve regurgitation was not associated with mortality for left ventricle patients