Pulmonary arterial hypertension associated with connective tissue disease and immunosuppressive therapy.

onnective tissue disease (CTD)-associated pulmonary arterial hypertension (CPAH) is the second most prevalent type of pulmonary arterial hypertension (PAH) after idiopathic PAH (IPAH). CPAH is estimated to account for 30% of all adult cases of PAH. Approximately 15% of mixed CTD (MCTD), 10% of systemic sclerosis (SSc), and several percent of systemic lupus erythematosus (SLE) patients develop PAH.1–3 In general, patients with CPAH have a poorer prognosis than those with other forms of PAH, except for pulmonary veno-occlusive disease (PVOD).4 A half of SSc patients may die within 1 year of PAH diagnosis without any treatment.5