BackgroundValve failure may occur after valve-sparing aortic root replacement. Little is known about the exact mechanisms of failure. This study analyzed reoperations after aortic root remodeling to determine failure modes, operative risk, and long-term outcome. MethodsBetween November 1995 and December 2019, 1084 patients were treated by root remodeling. Of these, 54 (49 male; aged 8 to 79 years) underwent reoperation for valve failure (1 week to 16 years postoperatively). The indications for reoperation were aortic regurgitation (n = 39), aortic stenosis (n = 6), endocarditis (n = 7), or ventricular septal defect (n = 2). The main causes of valve failure were cusp repair failure (n = 29), endocarditis (n = 7), and cusp retraction (n = 8). The patients were treated by valve replacement (n = 40) or cusp repair (n = 14). In 6 individuals, combined replacement of valve and root was performed. All 54 patients were followed up (mean, 69 ± 54 months after reoperation), and 1 patient was lost to follow-up. ResultsNo patient died in the hospital or had atrioventricular block development; 12 patients died late, with 10- and 15-year survivals of 87% ± 5.1% and 64% ± 10.6%, respectively. Of the 14 patients who underwent repeat cusp repair, 7 (50%) are still alive with stable valve function, 17 months to 15 years after their reoperation. Eleven patients required a second reoperation leading to a freedom from repeat reintervention rate of 68% ± 9.7% at 15 years. ConclusionsThe main causes of failure of root remodeling are cusp related. Reoperations can be performed with low morbidity and mortality. In selected patients, isolated cusp repair may be an option.