P3528Timing of pulmonary valve replacement in patients with corrected tetralogy of fallot influences postoperative QRS duration

Background: Surgical pulmonary valve replacement (PVR) after correction of tetralogy of Fallot (TOF) provides an effective relief from chronic pulmonary regurgitation (PR). However, timing of PVR remains one of the most heavily debated topics in congenital cardiac surgery. Progressive QRS duration has been associated with malignant ventricular arrhythmia, dysfunction and sudden cardiac death. The aim of this study was to analyze the temporal evolution of QRS duration before and after PVR, and determine optimal timing to prevent progressive QRS prolongation. Methods: Between Augustus 1987 and December 2017, 158 consecutive patients underwent PVR after previous correction with transannular patch. Hemodynamic indications were severe PR (n=137; 86.7%), severe stenosis (n=3; 1.9%) and mixed PR and stenosis (n=18; 11.4%). All 3549 available serial standard 12-lead surface QRS measurements of 158 (100%) patients were analyzed with linear mixed effect modeling. In addition, 1470 serial echocardiograms of 154 (97.5%) patients were retrieved and analyzed using generalized mixed effects modeling. QRS duration and pulmonary regurgitation were explored as a function of time to PVR and baseline characteristics.