Peak QRS/T ratio and the spatial ventricular gradient differentiate acute vs chronic left bundle branch block after transcatheter aortic valve replacement

Background: Differentiating chronic from acute left bundle branch block (LBBB) is useful in various cardiac disorders. Peak QRS/T ratio, a measure of cardiac memory, can differentiate chronic from acute LBBB with high sensitivity and specificity, but its utility in post-transcatheter aortic valve replacement (TAVR) patients with LBBB is unclear. Objective: This study aimed to validate the QRS/T ratio for differentiating chronic/acute LBBB in post-TAVR patients and assess whether the spatial ventricular gradient (SVG), which integrates 3-dimensional depolarization/repolarization throughout the cardiac cycle, could also distinguish chronic from acute LBBB. Methods: This was a post hoc analysis of a prospective, observational, single-center TAVR study. After TAVR, patients were classified as acute (new