Impact of PR interval prolongation on the risk of high-grade conductive disorders after transcatheter aortic valve implantation

The development of high-grade conduction disturbances is one of the most frequent complications after transcatheter aortic valve implantation (TAVI). Variation in atrioventricular conduction time (PR interval) after TAVI and its specific impact on the risk of permanent pacing implantation (PPI) have been poorly described. The aim of this study was to evaluate the impact of increase in PR interval after TAVI on the incidence of PPI for high-grade conductive disorder. This is a single-center retrospective cohort analysis of 1466 patients undergoing TAVI from January 2010 to December 2018. We excluded patients with prior pacemaker, non-sinus rhythm, TAVI by transapical or transaortic approach and PPI after TAVI for sick sinus syndrome. We observed the variation in PR interval of the electrocardiogram before TAVI (baseline) and at day 1 (D1) of the procedure. The final analysis included 902 patients. Among them, 342 (37.9%) had a previous first-degree atrioventricular block and 13.2% had a new one after TAVI. 207 patients (23.0%) received a PPI for conductive disorders. The mean analysable PR prolongation in 779 patients was 8 ± 26 ms, the risk of developing a high-grade conductive disorder was estimated at 30.6% when PR prolongation was ≥ 40 ms. Multivariable analysis revealed that prolongation of PR interval ≥ 40 ms on D1 was by itself associated with the occurrence of these high-grade conductive disturbances (HR = 4.9 [2.5; 10.0], P < 0.001) more significantly than preexisting right bundle branch block (HR 3.6 [1.7; 7.7], P = 0.001) or de novo left bundle branch block (HR 2.8 [1.5; 5.2], P = 0.001) ( Fig. 1 ). PR interval prolongation greater than or equal to 40 ms at D1 of transcatheter aortic valve implantation is a critical factor to consider in estimating the risk of PPI for high-grade conductive disorder.