Abstract 17229: Atrioventricular Conduction System Changes During Transcatheter Aortic Valve Replacement (TAVR)

Abstract

Introduction: Transcatheter aortic valve replacement (TAVR) is complicated by atrioventricular (AV) conduction disturbance in 8-15% of cases. Prior studies have not utilized complete electrophysiology studies (EPS) with continuous recording during TAVR. We sought to better understand the potential utility of intraprocedural electrophysiologic study to identify patients at risk for developing high-grade AV conduction disturbances after TAVR. Hypothesis: Intraprocedural EPS has the potential to identify patients at risk of developing AV conduction block after TAVR. Methods: We conducted a prospective study of TAVR patients at BIDMC between 5/2021-3/2023, excluding those with pre-existing pacemakers/defibrillators. We performed EPS in the cath lab prior to and after valve replacement: atrial pacing to AV block, recording His bundle electrogram (HBE) and RV pacing to assess VA conduction. When possible we recorded the HBE continuously during valve implant. Results: We studied 400 consecutive patients. Forty-three patients (10.8%) received permanent pacemakers (PPMs). Patients receiving PPM had significantly longer post-HV intervals, greater change in HV interval as well as longer AV Wenckebach cycle length after valve replacement. There were no differences in pre-TAVR AV Wenckebach cycle length or VA conduction. Twenty patients (46.5% of all PPMs) were implanted for AV block post discharge, and after adjustment for age, gender, and baseline HV interval, the only predictor of need for post-discharge PPM was peri-TAVR change in HV interval with an adjusted OR of 1.19 per each 10 ms increase. Conclusions: In contrast to prior studies, we have found that EPS at the time of TAVR may have utility in predicting AV conduction disturbances. Larger increases in HV interval and AV block CL were associated with need for PPM. Measuring the peri-TAVR change in HV interval may be useful in predicting late AV block.