Pacing burden and its development over time in patients with permanent pacemaker implantation following TAVI

Background/Purpose High-degree atrioventricular (AV) block with a need for subsequent permanent pacemaker (PPM) implantation is a frequent complication following transcatheter aortic valve implantation (TAVI). However, not only the predictors of AV block with the need for PPM implantation after TAVI, but also pacing burden and the development of pacing burden over time remain poorly understood. Methods We systematically evaluated the clinical and procedural characteristics and the need for PPM implantation in a cohort of 1500 consecutive patients without PPM undergoing transfemoral TAVI. Among these, 13% (n=193) required PPM implantation during or after TAVI due to high-degree AV block. We performed systematic device interrogation to determine the pacing burden at discharge, at 3 months and at 6 months post PPM implantation in a subgroup of 85 patients. Clinical characteristics and ECG parameters before and after TAVI were analyzed in order to identify predictors of pacing burden and its development over time. Results Mean patient age was 80 ± 7 years (49% female, 51% male). Among the patients, 20% received a single-chamber PPM due to permanent atrial fibrillation, 73% received a dual-chamber PPM, and 7% received a three-chamber PPM for cardiac resynchronization therapy. At discharge, 28% exhibited an intrinsic conduction, whereas 72% did not. At the time point of interrogation, 42% of patients exhibited intrinsic conduction at 3 months and 46% at 6 months (both p<0.001 compared to discharge). The mean pacing burden at discharge was 94%, which decreased significantly to 76% after 3 months and to 42% after 6 months (both p<0.001 compared to discharge). Patients with preserved intrinsic conduction more frequently exhibited post-interventional new onset left bundle branch block (72%, n=61) compared to those without preserved intrinsic conduction (28%, n=24, p<0.001). Multivariate regression analysis identified new onset LBBB as a significant predictor of low pacing burden (<10% VP) at 6 months (p=0.035, OR 2) and preserved intrinsic conduction (p=0.027, OR 12). Conclusion In summary, short-term follow-up demonstrated a significant increase of intrinsic conduction and significant decrease in pacing burden over 6 months following PPM implantation after TAVI. Post-interventional LBBB emerged as a significant predictor of low pacing burden and preserved intrinsic conduction.