Strain evaluation for mitral annular disjunction by echocardiography and magnetic resonance imaging: A case-control study

Abstract

BackgroundMitral annular disjunction (MAD) is an increasingly recognized entity associated with mitral valve prolapse (MVP), ventricular arrhythmias and death. Few studies have investigated the utility of myocardial deformation analysis in MAD. We compared chamber quantification including strain by transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR) between MVP patients with and without MAD. MethodsForty-two patients with MVP (21 with MAD, 21 without MAD) and 21 controls were studied. Global, basal and basal inferolateral (BIL) segmental strains were measured and compared using velocity-vector imaging TTE and feature-tracking CMR. ResultsMean age was 54 ± 17 years, 19 (46%) were female, and 19 (46%) underwent surgical mitral valve repair with no deaths during follow-up in the 2 groups with MVP. Patients with MAD and MVP had lower basal longitudinal strain by TTE than those with MVP without MAD. Those with MAD and MVP had lower magnitude in BIL and basal segments by circumferential and radial strain by CMR compared to those with MVP without MAD and controls. Amongst global strain parameters, CMR-derived global circumferential strain was independently associated with MAD diagnosis odds ratio 1.49 (per 1%), 95% confidence interval 1.09–2.05, P = 0.014, with optimal threshold of −18.0% having 76% sensitivity and specificity for MAD. ConclusionAbnormal circumferential and radial strain patterns in the basal segments by CMR may be useful for identifying regional LV dysfunction associated with MAD.