Pulmonary hypertension in sickle cell disease: mechanisms, diagnosis, and management.

Pulmonary hypertension affects nearly one-third of adults with sickle cell disease and is related to hemolysis. Although pulmonary pressures are not as high as in other forms of pulmonary hypertension, sickle cell patients poorly tolerate even moderate elevations of pulmonary pressures, because this complication predicts short survival. Tricuspid regurgitant jet velocity measured noninvasively by echocardiography is an adequate tool to screen for pulmonary hypertension. Because patients with pulmonary hypertension are older and often severely affected by other vaso-occlusive complications, optimizing their treatment with hydroxyurea or transfusions is important. Newer agents such as sildenafil and bosentan have demonstrated efficacy in other forms of pulmonary hypertension, and future clinical trials may prove them helpful in sickle cell patients.