It is important to note that this increase of Tricuspid velocity (a surrogate of pulmonary hypertension) and TAPSE could be caused by increased TRV with severe haemolysis, elevated right ventricular filling pressure, renal dysfunction, and high circulating erythropoietin concentrations especially among children with sickle cell anaemia [19]. This evidence concerns the gene EPO and pulmonary arterial hypertension.