Atrioventricular Conduction Changes After CoreValve Transcatheter Aortic Valve Implantation.

INTRODUCTION AND OBJECTIVES: Conduction disturbances often occur after CoreValve transcatheter aortic valve implantation. The aim was to analyze which cardiac conduction changes occur in patients with aortic stenosis treated with this type of prosthesis.

METHODS: A total of 181 patients with severe aortic stenosis treated with this prosthesis and studied by electrocardiography between April 2008 and December 2013 were selected. A subgroup of 137 (75.7%) consecutive patients was studied by intracardiac electrocardiogram before and after prosthesis implantation. The primary endpoint of the study was the need for a permanent pacemaker within 72 hours after prosthesis implantation. Numerous variables to predict this possibility were analyzed.

RESULTS: Following implantation, PR and QRS intervals were increased from 173±47 ms to 190±52ms (P < .01) and from 98±22ms to 129±24 ms (P < .01), whereas the A-H and H-V intervals were prolonged from 95±39ms to 108±41ms (P < .01) and from 54±10ms to 66±23ms (P < .01). A total of 89 (49%) patients had new-onset left bundle-branch block, and 33 (25%) required a pacemaker within the first 72hours. The independent predictors for a pacemaker were baseline right bundle-branch block and prosthetic depth. Intracardiac intervals had no predictive value. In addition, 13 patients required a pacemaker after 72 hours.

CONCLUSIONS: CoreValve prosthesis implantation has a high incidence of conduction disturbance, with left bundle-branch block being the most common. A total of 25% of patients required a permanent pacemaker. The need for a pacemaker was related to baseline right bundle-branch block and prosthetic depth.