Predictors and Permanency of Cardiac Conduction Disorders and Necessity of Pacing after Transcatheter Aortic Valve Implantation

BACKGROUND: Transcatheter aortic valve implantation (TAVI) with the Medtronic-CoreValve bioprosthesis (CoreValve Inc., Irvine, CA, USA) is associated with a high incidence of new-onset left bundle branch block (LBBB) and cardiac conduction disorders (CCDs) requiring permanent pacemaker (PPM) implantation. Our objective was to investigate the predictors and permanency of CCDs after TAVI and specifically to evaluate the necessity for pacing. METHODS: In this single-center study, we included patients who underwent TAVI with the Medtronic-CoreValve bioprosthesis. Electrocardiographic evaluation was performed pre- and post-TAVI and at follow-up. Pacemaker follow-up data were obtained and analyzed. RESULTS: We included 121 patients (age 81 ± 8 years). LBBB developed in 47 patients, for which prosthesis size (26 mm; odds ratio OR: 4.1, 95% confidence interval CI: 1.32-12.34, P = 0.01) and prosthesis depth (OR: 1.3, 95% CI: 1.09-1.57, P = 0.004) were independent predictors. In 19%, this new-onset LBBB was temporary. Requirement for a PPM occurred in 23 patients, for which mitral annular calcification (MAC; OR: 1.3, 95% CI: 1.05-1.56, P = 0.02) and preexisting right bundle branch block (RBBB; OR: 8.5, 95%CI: 1.61-44.91, P = 0.01) were independent predictors. At follow-up, 52% of the patients were continuously paced, but 22% of the patients had adequate atrioventricular conduction without the necessity for pacing. In the other 26% of the patients there was intermittent pacing. CONCLUSION: There is a high incidence of new-onset LBBB and PPM implantation following TAVI with a Medtronic-CoreValve bioprosthesis. Prosthesis depth and size were predictors for new LBBB, while MAC and preexistent RBBB were predictors for PPM implantation. In approximately one fifth of the patients, new-onset LBBB and the necessity for pacing are only temporary.