Cardiovascular Magnetic Resonance Mapping and Strain Assessment for the Diagnosis of Cardiac Involvement in Idiopathic Inflammatory Myopathy Patients With Preserved Left Ventricular Ejection Fraction

PURPOSE The aim of the study was to evaluate the role of cardiac magnetic resonance (CMR) mapping and strain analysis in the identification of cardiac involvement in idiopathic inflammatory myopathy (IIM) patients with preserved left ventricular ejection fraction. MATERIALS AND METHODS In all, 38 IIM patients who underwent CMR examination at our institution were retrospectively included. Twenty-three age-matched healthy individuals served as controls. Mapping parameters including native T1, extracellular volume (ECV), and T2 mapping and strain parameters including global radial strain, global circumferential strain, and global longitudinal strain were measured semiautomatically using a dedicated processing software. All the mapping and strain values were compared between patients and controls. RESULTS Late gadolinium enhancement was only present in IIM patients (n=17, 44.7%). IIM patients showed higher native T1 (1346 vs. 1269 ms, P<0.001), ECV (31.1% vs. 27.4%, P<0.01), and higher T2 (44.4 vs. 39.2 ms, P<0.001) values compared with controls. The global radial strain (36.7% vs. 46.9%, P<0.001), global circumferential strain (-21.2% vs. -24.1%, P<0.01), and global longitudinal strain (-13.6% vs. -15.6%, P<0.05) values were significantly reduced compared with controls. CONCLUSIONS Native T1, ECV, T2 values, and global strain values may hold promise for the detection of subclinical myocardial involvement in IIM patients with preserved left ventricular ejection fraction.