Clinical Research Directory

Inclusion Criteria: * Age between 10 and 25 years old * Sickle cell disease with hemoglobin SS, SC or S-B\^0 thalassemia confirmed on hemoglobin electrophoresis * Tricuspid regurgitant jet velocity (TRJV) equal to or greater than 2.5 m/sec on 2 baseline Doppler echocardiograms at least 3 months apart Exclusion Criteria: * Patients already being treated with hydroxyurea * Patients on a chronic transfusion protocol * Patients with evidence of hepatic (alanine aminotransferase \[ALT\] equal to or greater than 2 SD above normal) or renal dysfunction (creatinine \[Cr\] equal to or greater than 2 SD above normal) * Patients who are pregnant * Patients with documented causes of severe pulmonary hypertension other than from SCD