Permanent pacing after transcatheter aortic valve implantation of a CoreValve prosthesis as determined by electrocardiographic and electrophysiological predictors: a single-centre experience

The most frequent conduction complications with transcatheter aortic valve implantation (TAVI) are complete atrioventricular (AV) block and new bundle branch block (BB). The purpose of this study was to assess clinical, electrocardiographic, and electrophysiological predictors of conduction abnormalities in patients (pts) undergoing TAVI with the CoreValve prosthesis. The secondary end points were the long-term rhythm follow-up and the recovery of conduction. Forty-five consecutive pts with severe aortic stenosis, New York Heart Association II/III, and normal or slightly impaired left ventricular function who underwent CoreValve transcatheter implantation were randomized 2:1 to electrocardiographic and electrocardiographic plus electrophysiological evaluations. Pacemakers were implanted in pts with complete AV block. Follow-up was performed at 1, 6, 12, and 24 months. Conduction was affected in the total group of pts undergoing TAVI. The PR lengthened compared with the baseline but did not exceed the normal cut-off of 200 ms, and the QRS widened, basically due to new left bundle branch blocks (LBBBs). Within 1 month of follow-up, 10 pts (22%) developed complete AV block (9 peri-procedurally-20%) and 15 pts (33%) developed a new bundle BB, with LBBBs being the most common (14-31%). In the 30 pts who underwent an electrophysiological study, analysis showed that prolonged HV intervals were prognostic for pacemaker implantation. Follow-up in the total study group revealed that only 4 of the 10 (9%) initial implantations remained completely pacemaker dependent. Conduction was affected in all pts undergoing TAVI, but serious complications that required permanent pacing generally occurred in pts with pre-existing conduction abnormalities.