Effect of mitral annular calcification on outcomes following transcatheter aortic valve replacement

Abstract

Objectives: Mitral annular calcification (MAC) may influence outcomes following transcatheter aortic valve replacement (TAVR). However, the prognostic impact of MAC severity and its anatomical distribution remains unclear. This study aimed to evaluate the impact of MAC severity and anatomical distribution on outcomes after TAVR.

Methods: We retrospectively analyzed consecutive patients who underwent TAVR between 2016 and 2021 at our institution. Patients with prior permanent pacemaker implantation were excluded. MAC severity and segmental distribution were assessed using preprocedural computed tomography and patients were accordingly categorized into the no, mild/moderate, or severe MAC group by MAC severity.

Results: A total of 642 patients met the inclusion criteria and were included in the final analysis. Severe MAC was present in 15% of patients. The median follow-up time was 2.1 years (interquartile range: 1.3-3.6 years). Seventy patients (10.9%) required new pacemaker implantation due to complete atrioventricular block, and 158 patients (24.6%) died within 3 years. Three-year survival rates were comparable among groups (68.7%, 68.0%, and 69.6%, respectively; p = not significant). Neither MAC severity nor overall distribution independently predicted mortality. While pacemaker implantation was more frequent in patients with severe MAC (20%), multivariable analysis identified MAC localization in the A3 segment (rather than overall severity) as an independent predictor of pacemaker implantation (odds ratio 5.10, p < 0.001).

Conclusions: MAC localization in the A3 segment, rather than overall severity, was independently associated with conduction disturbance requiring pacemaker implantation after TAVR.

Keywords: complete atrioventricular block; mitral annular calcification; mitral valve disease; transcatheter aortic valve replacement.