Measurement of extracellular volume fraction by cardiac magnetic resonance imaging detects diffuse myocardial fibrosis in systemic sclerosis

Abstract

Summary We measured extracellular volume fraction (Ve) from pre- and post-contrast T1 maps of the left ventricle in 13 patients with systemic sclerosis (SSc) and 13 agematched controls. SSc patients and controls were similar with regard to LV and RV mass, volumes, and function. However, Ve was significantly higher in SSc patients than in controls, even when patients with visible late gadolinium enhancement were excluded. Ve correlated with SSc severity as measured by the modified Rodnan Skin Score. Ve may be valuable for detection of myocardial involvement in SSc, even when conventional CMR appears normal. Background Primary cardiac involvement is common in systemic sclerosis (SSc) and responsible for 25% of deaths. Myocardial extracellular volume fraction (Ve), derived from cardiac magnetic resonance (CMR) T1 mapping of the myocardium, has been shown to quantify diffuse myocardial fibrosis (DMF) - but its utility in SSc has not been studied. We hypothesized that subjects with SSc have a higher Ve compared to controls and that patients with worse SSc severity have higher Ve. Methods CMR was performed in 13 SSc patients (5 diffuse and 8 limited cutaneous) and 13 age-matched controls. Cine, pre- and post- contrast T1 mapping, and late gadolinium enhanced (LGE) imaging was performed. LV mass index (LVMi), LV end-diastolic volume index (LVEDVi), LV ejection fraction (EF), RV mass index (RVMi), RV