Anatomical Computer Tomography Parameter Prediction of Pacemaker Requirement Following Transcatheter Aortic Valve Implantation

Abstract

Permanent pacemaker (PPM) requirement following transcatheter aortic valve implantation (TAVI) is a known complication with limited predictability using conventional prognosticators. Recent studies suggest a PPM requirement correlation with computed tomography (CT)-guided anatomical predictors including membranous septal length. This study aimed to evaluate the utility of CT-based anatomical markers including virtual annulus-distal membranous septum distance (vMSL) in PPM requirement prediction following TAVI. Patients undergoing TAVI in Wellington Regional Hospital between July 2017 and August 2022 were screened. Patients with pre-existing aortic valve replacement, PPM, or incomplete data were excluded. Association of PPM requirement with vMSL (primary endpoint), total membranous septal length (tMSL), and the implantation depth below the vMSL (vMSL-IH) (secondary endpoints) were evaluated. Electronic records and Canon’s Vitrea system were used for data collation. Twenty of 148 patients (14%) required PPM within 30 days (65% male, mean age 80±9 years). Patients were grouped into quartiles according to vMSL. Quartile comparison revealed a statistically significant difference in PPM rates between vMSL ≤4.8 mm vs >4.8 mm (RR 1.6; p=0.029). There were no statistically significant differences in age (p=0.096), implantation height (p=0.158), or valve oversizing percentage (p=0.812) between quartiles. There were statistically significant between-group differences in the secondary predictors tMSL (p<0.001) and vMSL-IH (p=0.001). Further quartile comparison confirmed a significant difference between vMSL-IH ≤1.7 mm vs >1.7 mm (RR 2.0; p<0.001) but no difference was appreciable in tMSL. While PPM requirement following TAVI remains difficult to predict, anatomical prognosticators such as vMSL and vMSL-IH may provide meaningful contributions to risk prediction.