It may be difficult to differentiate hypertrophic cardiomyopathy (HCM) from hypertensive heart disease (HHD) especially when left ventricular wall thickness (LVWT) ≥15mm.

Because cardiovascular magnetic resonance (CMR) has emerged as an efficient technique to characterise morphologic, functional and tissue abnormalities, we investigate the discriminatory capacity of this technique by analysing different imaging markers in HCM and in HHD.

A total of 60 HCM patients (group 1) and 60 HHD subjects with left ventricular wall thickness ≥15mm without ischemic or other cardiac pathology (group 2) underwent CMR.

No differences were noted between the 2 groups with regards to mean ages, BMI, gender and creatinine clearance. The 2 groups had similar indexed LV mass (group 1: 107±11g/m² vs. group 2: 104±13g/m², P>0.05) but patients with HCM had higher LVWT compared with HHD patients (21.5±3mm vs. 16.3±1.2mm, P<0.001). Complete systolic anterior motion of the mitral valve (SAM) was frequent in group 1 patients while totally absent in group 2 (38% vs. 0%, P<0.0001). Late gadolinium enhancement (LGE) was significantly predominant in HCM patients (76% vs. 14%, P<0.0001). Compared with HHD group, native T1 was also significantly higher in HCM patients (1181±36ms vs. 1048±40ms, P<0.001). In multivariate analysis, presence of SAM and native T1 remained significant predictors of HCM.

These observations underscore the important role for CMR in the assessment of patients with HCM. CMR has several tools providing novel information in accurate discrimination between HCM and hypertensive heart disease.