Conventional and Novel Predictors of Permanent Pacemaker after TAVI in Atrial Fibrillation Patients.

BACKGROUND AND AIM OF THE STUDY: Atrial fibrillation (AF) is common in patients submitted for transcatheter aortic valve implantation (TAVI), and these patients are at higher risk of developing conduction system disturbances requiring pacemaker (PM) implantation. Conventional predictors for PM use in this population have limited applicability. It was hypothesized that a post-procedural heart rate reduction could gauge the degree of atrioventricular (AV) node injury, and that this would be a clinically useful predictor of a need for PM.

METHODS: All consecutive patients submitted for TAVI between December 2009 and August 2015 were included prospectively in a local registry. Clinical and electrocardiographic data and procedural details were recorded, and patients in sinus rhythm or with pre-existing PM were excluded. Heart rate (HR) at the start and end of the procedure were used to assess post-procedural HR reduction by calculating the HR ratio (HRratio = HRend/HRstart). The relationship between previously described predictors of PM, HRratio and implantation of a permanent PM during the 30 days after TAVI were analyzed using the Wilcoxon ranksum test and receiver operating characteristic (ROC) curve.

RESULTS: A total of 102 patients was submitted for TAVI, 24 of whom had AF and no previous PM. Of the latter 24 patients, 10 (41.6%) received a PM during the 30 days after TAVI. Conventional predictors of permanent PM such as male gender, left anterior hemiblock and right bundle branch block were not significantly associated with PM implantation. The HRratio was significantly lower in patients submitted for PM implantation (median 0.76, IQR 0.68-0.86 versus 1.18, IQR 1.10-1.26; p <0.001; Wilcoxon ranksum test). ROC curve analysis of the HRratio showed a good discrimination for the need of PPM with a c-statistic of 0.93. An optimal cut-off value of 0.9 predicted the need for PM implantation with a sensitivity of 90% and specificity of 92.8% CONCLUSIONS: Conventional predictors of PM after TAVI were not associated with PM implantation in patients with AF. The fall in post-procedural HR was significantly associated with PM implantation, with an HRratio cut-off value of 0.9 accurately predicting a need for PM within 30 days.