Combining evidence and experience in pulmonary hypertension.

T he term pulmonary hypertension (PH) describes a group of devastating and life-limiting diseases, defined by mean pulmonary artery pressure o25 mmHg at rest [1]. PH can be idiopathic in origin or can arise in association with a range of underlying causes. Clinical symptoms of progressive dyspnoea and decreasing exercise capacity, and the potential for the development of right heart failure, are common to all forms of PH, despite the differences in aetiology. Presently, PH is classified clinically, with the various subgroups sharing similar clinical presentations and pathogenetics [2].