Mitral annular disjunction in patients with severe aortic stenosis: Extent and reproducibility of measurements with computed tomography

T Tsianaka; I Matziris; A Kobe; A Euler; N Kuzo; L Erhart; S Leschka; R Manka; A M Kasel; F C Tanner; H Alkadhi; M Eberhard

doi:10.1016/j.ejro.2021.100335

Mitral annular disjunction in patients with severe aortic stenosis: Extent and reproducibility of measurements with computed tomography

Eur J Radiol Open. 2021 Mar 9:8:100335. doi: 10.1016/j.ejro.2021.100335. eCollection 2021.

Authors

T Tsianaka¹, I Matziris², A Kobe¹, A Euler¹, N Kuzo², L Erhart², S Leschka³, R Manka^{1

2

4}, A M Kasel², F C Tanner², H Alkadhi¹, M Eberhard¹

Affiliations

¹ Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Switzerland.
² Department of Cardiology, University Heart Center Zurich, Zurich, Switzerland.
³ Division of Radiology and Nuclear Medicine, Kantonsspital St.Gallen, Switzerland.
⁴ Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland.

Abstract

Objectives: To determine with CT the prevalence and extent of mitral annular disjunction (MAD) in patients undergoing transcatheter aortic valve replacement (TAVR) and its association with mitral valve disease and arrhythmia.

Methods: We retrospectively evaluated 408 patients (median age, 82 years; 186 females) with severe aortic stenosis undergoing ECG-gated cardiac CT with end-systolic data acquisition. Baseline and follow-up data were collected in the context of a national registry. Two blinded, independent observers evaluated the presence of MAD on multi-planar reformations. Maximum MAD distance (left atrial wall-mitral leaflet junction to left ventricular myocardium) and circumferential extent of MAD were assessed on CT using dedicated post-processing software. Associated mitral valve disease was determined with echocardiography.

Results: 7.8 % (32/408) of patients with severe aortic stenosis had MAD. The maximum MAD was 3.5 mm (interquartile range: 3.0-4.0 mm). The circumferential extent of MAD comprised 34 ± 15 % of the posterior and 26 ± 12 % of the entire mitral annulus. Intra- and interobserver agreement for the detection of MAD on CT were excellent (kappa: 0.90 ± 0.02 and 0.92 ± 0.02). Mitral regurgitation (p = 1.00) and severe mitral annular calcification (p = 0.29) were similarly prevalent in MAD and non-MAD patients. Significantly more patients with MAD (6/32; 19 %) had mitral valve prolapse compared to those without (6/376; 2 %; p < 0.001). MAD was not associated with arrhythmia before and after TAVR (p > 0.05).

Conclusions: Using CT, MAD was found in 7.8 % of patients with severe aortic stenosis, with a higher prevalence in patients with mitral valve prolapse. We found no association of MAD with arrhythmia before or after TAVR.

Keywords: CT, computed tomography; Computed tomography; ECG, electrocardiogram; IQR, inter-quartile range; MADmitral, annular disjunction; MR, mitral regurgitation; Mitral annular disjunction; Mitral valve; Mitral valve prolapse; TAVR, transcatheter aortic valve replacement; Transcatheter aortic valve replacement.