Hypertension artérielle pulmonaire associée aux connectivites : particularités cliniques et pronostiques

Pulmonary arterial hypertension (PAH) is a possible complication of all connective tissue disease (CTD). Systemic Sclerosis (SSc) is the main cause of PAH associated to CTD. The prevalence of PAH in SSc is about 10 % justifying a regular screening for PAH by echocardiography. Patients having a tricuspid jet velocity above 3 m/s without evident left cardiopathy are suspected to have PAH and need right heart catheterisation (RHC) for confirmation of the diagnosis. RHC is mandatory for the diagnosis of pulmonary hypertension as the definition is hemodynamic (mean pulmonary arterial pressure ≥ 25 mm Hg at rest). RHC may exclude post-capillary pulmonary hypertension which is frequent in SSc due to left ventricle diastolic dysfunction. Sometimes PAH and post-capillary pulmonary hypertension are associated. The mean 3-year survival of SSc-PAH is about 60 % which is not acceptable and must be improved through an earlier diagnosis and management. PAH is also possible in other CTD like systemic lupus, mixed connective tissue diseases, Sjögren syndrome, rheumatoid arthritis, polymyositis but more rarely. In these CTD screening for PAH is only needed in symptomatic patients (mainly with breathlessness). The survival of PAH-CTD patients other than SSc is usually a little better, particularly in systemic lupus with a 3-year survival above 70 %. CTD-PAH treatment algorithm is the same as in idiopathic PAH. However, immunosuppressive treatment could be useful in mild to moderate PAH associated to systemic lupus and mixed connective tissue disease.