Recent developments in connective tissue disease associated pulmonary arterial hypertension.

Connective tissue disease associated pulmonary arterial hypertension (CTD-PAH) has benefited from the major treatment advances that have occurred within pulmonary hypertension over the past three decades. Inclusion of CTD-PAH cases in pivotal clinical trials led to regulatory approval and drug availability. This has improved outcomes but there are additional challenges for management. First, the multifaceted co-morbidity related to the associated CTD needs treatment alongside PAH and may impact on diagnosis and evaluation of treatment response. Secondary, cardiac involvement, interstitial lung disease and predisposition to thromboembolism in CTD may lead to compound phenotypes where PH has multiple mechanisms as well as precapillary pulmonary vasculopathy of PAH. In general, especially for systemic sclerosis, CTD-PAH has worse long-term survival than idiopathic or familial PAH. However, CTD also present an opportunity for screening and early detection and treatment for associated PAH, and this may in the future be a major advantage over idiopathic disease where presentation inevitable only occurs at symptomatic stages and diagnosis may be delayed. This article reviews and summarises some of the recent developments in investigation and management of CTD-PAH.