Pulmonary hypertension in connective tissue disease. Report of three cases and review of the literature.

Patients with connective tissue disease (CTD) who are prone to developed isolated pulmonary hypertension (PH) are primarily young females with a history of Raynaud's phenomenon associated with an exertional dyspnoea. From the start of the disease, pulmonary function tests show a decreased diffusing capacity for carbon monoxide, while X-ray examination shows no obvious abnormalities such as interstitial fibrosis. All patients show, on electrocardiographic examination, evidence of right axis deviation and right ventricular hypertrophy. It has been suggested that PH is found mostly in patients with systemic scerlosis characterized by the CREST syndrome. The histopathological findings are intimal proliferation, narrowing of the vessel lumen and medial fibrosis. These are not specific for CTD. One would expect more signs of vasculitis. Neither signs of lung fibrosis, nor signs of pulmonary emboli are described.