Early initiation of disease-modifying therapy can impede or prevent diffuse myocardial fibrosis in sickle cell anemia

TO THE EDITOR:

The cardiomyopathy of sickle cell anemia (SCA) is characterized by ventricular diastolic dysfunction that is superimposed on an anemia-related hyperdynamic state.^1-3 Diastolic dysfunction has been recognized before and shown to portend early mortality in SCA,⁴ but the underlying causes of diastolic dysfunction were not understood.⁵ We recently showed that diffuse myocardial fibrosis is a common, if not defining, feature of the cardiomyopathy of SCA that is strongly associated with diastolic dysfunction.^6,7 Every participant with SCA (N = 25) who underwent cardiac magnetic resonance imaging (CMR) had marked diffuse myocardial fibrosis.⁶ Three quarters were receiving hydroxyurea at the time of their imaging,⁶ which had been first prescribed at a mean age of 11.3 years (range, 4.1-25.6 years). By design, individuals receiving chronic transfusions were excluded.

Given that fibrosis was universally present in...