Mild residual pulmonary stenosis in tetralogy of fallot reduces risk of pulmonary valve replacement

Current surgical strategies that aim at preventing pulmonary regurgitation in patients with corrected tetralogy of Fallot (cToF) may result in a certain grade of residual pulmonary stenosis (PS). The clinical implications of a postoperative residual PS in cToF patients remain unclear. Pulmonary valve replacement (PVR) is frequently needed during follow-up of cToF patients. The aim of the current study was to determine the role of residual PS in the need for PVR during follow-up in cToF patients. cToF patients were included if clinical follow-up after primary surgical correction had taken place for a minimum of 5 years. Patient characteristics, surgical factors, and postoperative factors were reviewed, with a special focus on the transpulmonic systolic gradient. Cox proportional hazards regression analysis was performed to identify predictors of PVR. Of 171 cToF patients, 71 (41.5%) underwent PVR after 24.2 years (interquartile range, 16.8-31.6 years). Year of birth, older age at corrective operation, and patch use significantly predicted PVR during follow-up. By contrast, a mild residual PS in cToF patients (peak systolic gradient, 15-30 mm Hg) independently reduced the risk of PVR, as compared with patients without PS (hazard ratio, 0.47; p = 0.02) and with moderate-to-severe PS (hazard ratio, 0.35; p = 0.01). In addition to the known risks factors for PVR, a postoperative mild residual PS reduces the risk of PVR during follow-up of cToF patients. This finding provides clinical evidence for a conservative PS relief during correction of ToF