Early intervention in pulmonary arterial hypertension associated with systemic sclerosis: an essential component of disease management

Pulmonary arterial hypertension (PAH) is a life-threatening complication of systemic sclerosis (SSc). However, PAH-specific treatments are available and can significantly improve survival of patients, especially those diagnosed in World Health Organization (WHO) functional class (FC) II. Registry data have shown that without screening, more than two-thirds of PAH-SSc patients are in WHO FC III or IV when diagnosed. The recognised predisposition of SSc patients to develop PAH should mean that an optimal screening programme will enable the early diagnosis of PAH, and provide the opportunity for earlier treatment, in this population. Evidence-based treatment guidelines advocate the use of oral PAH-specific therapies, including bosentan, ambrisentan, sildenafil (I-A recommendation), tadalafil (I-B recommendation) and sitaxentan (IIA-C recommendation), for patients in WHO FC II. A randomised, placebo-controlled trial of bosentan in WHO FC II PAH patients, including cases of PAH-SSc, showed improved haemodynamics in actively treated patients and a reduced risk of progression from WHO FC II to FC III. For PAH patients diagnosed in WHO FC III, the treatment goal is to improve to WHO FC II. Data from bosentan trials have shown that nearly one-quarter of patients in WHO FC III at baseline can attain WHO FC II status with monotherapy. Maintenance of PAH-SSc patients in WHO FC II with monotherapy is unrealistic, and sequential goal-directed combination therapy is now becoming an accepted treatment strategy. It is hoped that earlier diagnosis, coupled both with regular assessments to ensure treatment goals are being met and timely, appropriate treatment, will further improve the survival rates of those PAH-SSc patients.