RT Journal Article SR Electronic T1 Management of severe pulmonary arterial hypertension JF European Respiratory Review JO EUROPEAN RESPIRATORY REVIEW FD European Respiratory Society SP 279 OP 287 DO 10.1183/09059180.00008010 VO 19 IS 118 A1 J-L. VachiƩry A1 G. Simonneau YR 2010 UL http://err.ersjournals.com/content/19/118/279.abstract AB Pulmonary arterial hypertension (PAH) is a severe, progressive condition of the small pulmonary vessels that leads to increased pulmonary vascular resistance, right ventricular failure and death. Patients in World Health Organization functional class (WHO FC) IV are the most severely affected in terms of disease severity, symptomatic impairment, exercise capacity and haemodynamics, with a very poor prognosis and low survival rate. Recent developments in PAH-specific therapies have conferred significant prognostic improvements upon PAH patients, especially when coupled with management strategies such as goal-oriented therapy and combination treatment. Despite these important developments, the outlook for WHO FC IV PAH patients remains poor. This article examines the recommendations for WHO FC IV patients that appear in current PAH treatment guidelines and the research underpinning this guidance, and discusses possible future directions for treatment of this severely unwell patient population.