Thirty surviving patients after corrective surgery for tetralogy of Fallot with right ventricular outflow tract reconstruction (RVOTR) using monocusp ventricular outflow patch (MVOP) were reviewed retrospectively to determine the long-term results. The age at operation ranged from 2 to 55 years with a mean of 19 years, and follow-up extended to 18.2 years (cumulative: 345.4 patient-year). There were 4 late deaths (1.2% per patient-year), and the cumulative survival rate was 85.3% at 18 years after the corrective surgery. Eight patients (2.3% per patient-year) required intracardiac reoperations mostly resulted from problems after RVOTR with MVOP, such as recurrent stenosis of right ventricular outflow tract (3 cases) or pulmonary valvular incompetence (4 cases). In addition, one patient underwent balloon angioplasty for the recurrent stenosis located in the distal end of MVOP. Freedom from surgical or catheter reintervention for the MVOP-related complication was 60.6% at 18 years after the corrective surgery. MVOP caused compression of the pulmonary artery at the distal end of the anastomosis and reoperation in a younger patients quite early after the corrective surgery. Like other transannular patches, tissue failure and degeneration of MVOP were inevitable, and resulted in severe pulmonary valvular incompetence that required the valve replacement in 4 patients (1.3% per patient-year). Freedom from pulmonary valve replacement was 71.2% at 18 years after the corrective surgery. As long-term results, our experiences emphasize the need for an innovative transannular patch that possesses significantly better long-term durability.