Background: The purpose of this study is to assess the electrocardiographic and electrophysiological parameters of conduction abnormalities in patients undergoing transcatheter aortic valve implantation (TAVI) due to severe aortic valve stenosis.

Methods: The study included 55 patients who underwent TAVI using either the Boston Scientific Lotus (n:25) (Boston Scientific, Natick, MA, USA) or Edwards Sapien XT (n:30) (Edwards Lifesciences, Irvine, CA, USA) prostheses. An electrophysiological study (EPS) was performed in the catheterization room immediately before the initial balloon valvuloplasty and immediately after prosthesis implantation.

Results: QRS duration and His-bundle to His-ventricle (HV) intervals, which were similar between the two groups before the procedure, were found to be significantly higher in the Lotus valve group postprocedure. Permanent pacemakers (PPMs) were required more frequently in the Lotus group than in the Sapien XT group at discharge (24.0% vs 6.7%, P = 0.07). With the exception of a higher prevalence of paravalvular leakage (P < 0.001) in patients undergoing Sapien XT implantation, other clinical outcomes were similar between the two groups. Multiple regression analysis revealed that baseline atrioventricular (AV) conduction disorders and HV intervals after the procedure were independently associated with PPM implantation after TAVI.

Conclusion: In this first study comparing the findings of EPS and electrocardiography, the impact of the Lotus valve on AV conduction systems was greater than that of the Sapien XT. However, the need for PPM was higher in the Lotus valve than in the Sapien XT. PPM requirement is related to valve design; it may decrease with reduced frame height and metal burden in novel valve systems.