Identification of patients with mitral annular disjunction and the highest risk of ventricular arrhythmias using advanced echocardiography tools

Mitral annular disjunction (MAD) is an abnormal atrial displacement of the mitral valve leaflet hinge point associated with mitral valve prolapse (MVP) and ventricular arrhythmias.

Our study's purpose was to check whether two-dimensional (2D) echocardiography using speckle tracking (STE) and myocardial work (MW) analysis may allow us to detect patients at the highest risk of ventricular arrhythmias.

Sixty-two patients with MAD detected in cardiac magnetic resonance (CMR) enrolled in the study and had performed echocardiography with STE assessment. Patients with any other than MVP structural heart diseases and more than moderate mitral regurgitation were excluded. The primary end-point (EP) was defined as complex ventricular arrhythmias (frequent ventricular premature beats (more than 5%), non-sustained and sustained ventricular tachycardia, and ventricular fibrillation).

EP was noticed in 13 (21%) patients. MVP presented in 38 (61%) patients; however, it did not predict the EP. Patients with EP did not differ regarding clinical parameters or standard echocardiographic measures but more often were treated with beta-blockers and had significantly worse left ventricular ejection fraction (LVEF): 55 (51 – 56)% for EP + group in comparison to 58 (54 – 61)% for EP- group (p=0.031). LVEF, global longitudinal strain (GLS), and global constructive work (GCW) were accurate predictors of the arrhythmic end-points with pre-specified cut-off values of 59%, -21% and 2265 mmHg% respectively with odds ratio (OR) 11.4 (1.35 – 96.36) for LVEF (p=0.009), 5.73 (1.46 – 22.51) for GLS (p=0.019), and 7.19 (1.38-37.31) for GCW (p=0.019). The highest predictive value of the end-point occurrence was reached for a combination of all these parameters: OR 55.71 (2.73 – 1137.52), p<0.001 (Figure).

2D echocardiography using STE and MW assessment could be valuable for assessing arrhythmic risk in MAD patients regardless of MVP presence. GLS and GCW measures, in addition to LVEF, could help reveal the patients at the highest risk of ventricular arrhythmias.