Prevention of diffuse myocardial fibrosis in SCA with early initiation of disease-modifying therapy. Patients who had early initiation and uninterrupted use of hydroxyurea or chronic transfusions had significantly less myocardial fibrosis than patients with no early therapy. Mean ECV was 0.30, which was significantly lower than the ECV of individuals with SCA who have not received early uninterrupted therapy (0.44, P = .002) and not different from normal controls (0.26 ± 0.02; P = .11).