Quantification of Myocardial Extracellular Volume Fraction with Cardiac MR Imaging for Early Detection of Left Ventricle Involvement in Systemic Sclerosis

Abstract

To determine whether extracellular volume fraction (ECV) quantification at cardiac magnetic resonance (MR) imaging can demonstrate subclinical left ventricle (LV) abnormalities in a cohort of consecutive systemic sclerosis (SS) patients, and to investigate the relationship between ECV and diastolic and systolic LV function. All subjects gave their written informed consent. The protocol was approved by the ethics committee. ECV quantification with cardiac MR imaging was prospectively performed in 33 consecutive SS patients with normal echocardiography results and no late gadolinium chelate enhancement at MR imaging. Left ventricular and atrial volumes and peak circumferential strain were measured at cardiac MR imaging. Diastolic function was assessed at echocardiography. The results were compared with those of 16 age-matched healthy control subjects by using Mann-Whitney and Kruskal-Wallis tests. SS patients had significantly higher global ECV (P < .001) and higher local ECV for all basal and midventricular LV segments. Global ECV significantly correlated with left atrial volume (P = .002) and with the grade of diastolic dysfunction (P = .016). The majority of SS patients (63%; 21 of 33 patients) had a high global ECV and a low global systolic circumferential strain. ECV quantification can identify LV abnormalities at an early stage in SS patients. These abnormalities may reflect increase in diffuse myocardial fibrosis and are associated with diastolic LV dysfunction.