Evaluation of: Parent F, Bachir D, Inamo J et al. A hemodynamic study of pulmonary hypertension in sickle cell disease. N. Engl. J. Med. 365(1), 44–53 (2011); Fonseca GH, Souza R, Salemi VM, Jardim CV, Gualandro SF. Pulmonary hypertension diagnosed by right heart catheterization in sickle cell disease. Eur. Respir. J. doi:10.1183/09031936.00134410 (2011) (Epub ahead of print).
Three new large screening studies of patients with sickle cell disease for pulmonary hypertension have now been published. Two of these studies included comprehensive right heart catheterization of all patients with an elevation in the estimated pulmonary artery systolic pressure. Together, these studies show that pulmonary hypertension, defined by a mean pulmonary artery pressure greater than or equal to 25 mmHg, occurs in approximately 10% of all adult sickle cell disease patients. Pulmonary hypertension in these studies is associated with hemolytic anemia, renal insufficiency, leg ulcers, increasing age, low exercise capacity and high levels of N-terminal pro-brain natriuretic peptide, but not with the rates of vaso-occlusive crisis or the acute chest syndrome, confirming prior epidemiological studies in adult sickle cell disease patients. The presence of pulmonary hypertension diagnosed by echocardiography or right heart catheterization indicates a significant and independent risk factor for prospective mortality.