Cardiac conduction abnormalities associated with pacemaker implantation after transcatheter aortic valve replacement

Background Complete heart block is a known complication after transcatheter aortic valve replacement (TAVR), often requiring pacemaker implantation within 24 hours of the procedure. However, clinical markers for delayed progression to complete heart block after TAVR remain unclear. Objectives We examined electrocardiographic data that may correlate with delayed progression to complete heart block and need for pacemaker. Methods This is a single-center retrospective study of 608 patients who underwent TAVR between April 2008 and June 2017. We excluded 164 (27.0%) patients due to having a pacemaker before the procedure or expiring within 24 hours of the procedure (8, 1.3%). We excluded an additional 50 (8.2%) patients who received a pacemaker within 24 hours of the procedure. Electrocardiograms (EKGs) obtained after the procedure were compared to the preprocedural EKG to detect new changes. Results Left bundle branch block, intraventricular conduction delay, left anterior fascicular block, and right bundle branch block were the most commonly seen conduction abnormalities after TAVR (25.1%, 10.9%, 7.5%, and 3.6%, respectively). Both left bundle branch block (odds ratio [OR] = 2.77 [95% confidence interval (CI): 1.24-6.22]) and right bundle branch block (OR = 13.2 [95% CI: 4.18-41.70]) carried an increased risk of pacemaker implantation after TAVR. Additionally, Delta PR greater than 40 ms from baseline also carried an increased risk of pacemaker implantation (OR = 3.53 [95% CI: 1.49-8.37]). Conclusion Left bundle branch block, right bundle branch block, and Delta PR greater than 40 ms were all associated with delayed progression to complete heart block and need for pacemaker implantation after TAVR.