Myocardial involvement and deformation abnormalities in idiopathic inflammatory myopathy assessed by CMR feature tracking.

BACKGROUND Cardiac involvement has been described in idiopathic inflammatory myopathies (IIM), including non-specific ECG and echocardiographic findings. Aim of our study was to evaluate myocardial deformation parameters in IIM and to correlate them with late gadolinium enhancement (LGE) findings using cardiac magnetic resonance imaging (CMR). METHODS Forty-seven consecutive patients with histologically proven IIM were included into our study. Twenty-five healthy volunteers were used as a control group. All patients and controls underwent CMR examination using a 1.5 T scanner including functional cine and LGE imaging. After a mean follow-up of 234.7 ± 79.5 days a second CMR examination was performed in IIM patients. RESULTS In comparison to healthy volunteers, IIM patients had lower left ventricular mass and left ventricular global radial, circumferential and longitudinal strain. There was no significant difference in left ventricular ejection fraction. Patients with LGE (N = 28) had lower left ventricular ejection fraction (p = 0.016), global right and left ventricular longitudinal strain (p = 0.014 and p = 0.005) and global left ventricular diastolic longitudinal strain rate (p = 0.001) compared to patients without LGE (N = 19). In IIM patients, a significant decrease of left ventricular ejection fraction, left ventricular mass and all measured deformation parameters was observed between baseline and follow-up CMR. CONCLUSION Cardiac involvement in IIM is frequent. Impairment of systolic and diastolic deformation parameters and a worsening over time can be observed. CMR is a useful tool for cardiac diagnostic work-up of these patients.