Changes in atrioventricular conduction and predictors of pacemaker need after percutaneous implantation of the CoreValve®. Aortic valve prosthesis.

INTRODUCTION AND OBJECTIVES Although changes in atrioventricular conduction frequently occur after percutaneous implantation of an aortic valve prosthesis, little is known about the mechanisms involved or how these changes progress. We investigated ECG abnormalities and predictors of pacemaker need after percutaneous implantation of the CoreValve® aortic valve prosthesis. METHODS Between April 2008 and October 2009, 65 patients with symptomatic severe aortic stenosis received a CoreValve® prosthesis. Clinical and ECG parameters were recorded and predictors of pacemaker need due to advanced atrioventricular block were investigated. The analysis excluded three patients because they had pacemakers and a fourth who died during the procedure. RESULTS The patients' mean age was 79 ± 7.8 years and their logistic EuroSCORE was 20 ± 14%. Implantation was successful in 98.4%. After implantation, 47.5% had left bundle branch block and 21 patients (34.4%) required a permanent pacemaker. The need for a pacemaker was associated with a greater depth of prosthesis implantation in the left ventricular outflow tract (LVOT): 13 ± 2.5 mm vs. 8.8 ± 2.8 mm (P< .001). Moreover, depth was the only predictor: odds ratio 1.9, 95% confidence interval 1.19-3.05 (P< .007). A cutpoint of 11.1 mm for the prosthesis depth in the LVOT had a sensitivity of 81% and a specificity of 84.6% for predicting the need for a pacemaker. CONCLUSIONS After CoreValve® aortic valve prosthesis implantation, a high percentage of patients needed a permanent pacemaker for advanced atrioventricular block. The only independent predictor was the depth of the prosthesis in the LVOT, which could serve as an early indicator of pacemaker need.