Cardiac computed tomography-based assessment of mitral annular calcification in patients undergoing mitral transcatheter edge-to-edge repair

Abstract

BackgroundThe role of assessment of mitral annular calcification (MAC) using cardiac computed tomography (CCT) in mitral transcatheter edge-to-edge repair (TEER) remains unclear. The aim of this study was to investigate the association of MAC assessed by CCT with procedural and clinical outcomes in patients undergoing TEER. MethodsWe retrospectively analyzed 275 patients who underwent pre-procedural CCT prior TEER. Mitral calcium volume (MCV) and MAC score were measured by CCT. Functional procedural success was defined as residual mitral regurgitation of ≤2+ with mean transmitral gradient of <5 ​mmHg at discharge. All-cause mortality within two years after TEER was collected. ResultsMAC was present in 115 of 275 patients (41.8 %). The median MCV was 198 ​mm3 (interquartile range [IQR]: 84 to 863 ​mm3), and the median MAC score was 3 (IQR: 2 to 4). Higher MCV and MAC score were inversely related to the rate of functional procedural success, independently of anatomical features of mitral valve. Patients with moderate/severe MAC, defined as MAC score of ≥4, had a lower rate of functional procedural success than those without MAC (56.1 ​% vs. 81.3 ​%; p ​= ​0.002). Moreover, higher MCV and MAC score were associated with a higher risk of all-cause mortality within two years, irrespective of baseline characteristics and functional procedural success. ConclusionsThe presence and burden of MAC assessed by CCT were associated with procedural and clinical outcomes in patients undergoing TEER. The CCT-based assessment of MAC may improve patient selection for TEER.