Diagnostic opportunities of magnetic resonant imagingmri of heart in differential diagnosis of phenotypical forms of hypertrophic cardiomyopathy

Abstract

Introduction. Phenotype variants of left ventricular (LV) remodeling in patients with hypertrophic cardiomyopathy (HCM) are often associated with abnormalities of the mitral valve (MV), myocardiumstructure, contributing to the development of medium and/or subaortic obstruction. Itcauses the detail visualization of morphological obstruction substrates, tissue characteristics.Aim. To evaluate the possibilities of magnetic resonance imaging (MRI) in the diagnosis of various forms of HCM and combined abnormalities.Materials and methods. 75 patients with suspected HCM were examined. For verification, all patients underwentMRI using protocol: short-pulse T1w-TSE/ T2w-TSE (STIR), gradient echo in cine (CINE), T1-weighted post-contrast images (Inversion Recovery IR-MDE). Results. Patients classified into 4 types according to the anatomical principle (Wiggle E.D. et al., 1985). In addition to the most frequent forms affecting the interventricular septum (IVS) — 64 patients, unusual forms covering the apical zones and papillary muscles — 11 patients. The majority of patients were diagnosed with abnormalities of MV, divided into abnormalities of the number and position of papillary muscles, as well as the ratio of chords and muscles. Myocardial crypts were diagnosed in 12 patients, some combined with areas of non-compact myocardium. Post-contrast visualization using the delayed contrast technique allowed differentiating HCM with accumulation diseases, excluding cavity thrombosis, and evaluating the severity of myocardial fibrosis.Conclusions. MRI allows to estimate in details anatomic picture of LV remodeling, to diagnose features of the mitral valve, tissue characteristics that allows to stratify risk of sudden death, classify the HCM phenotype form and to determine the volume of surgical intervention.