Pulmonary hypertension was first reported as a consequence of dermatomyositis in the late 1950s. The pulmonary hypertension was thought to be the result of degenerative and occlusive changes in the smaller branches of the pulmonary artery tree. In an autopsy series, Denbow et al examined the lungs and cardiovascular system of 20 patients with polymyositis. Four of 20 patients had small vessel disease characterized by smooth muscle hyperplasia of the medial portion of the blood vessel wall which was confined to the myocardium and lungs without involvement of other organs. More recently, another case report emphasized the severity of pulmonary hypertension in a patient with polymyositis. Postmortem examination of the pulmonary vasculature revealed fibrous intimal proliferation of the small pulmonary arteries. The pulmonary parenchyma revealed focal interstitial fibrosis. flovent inhaler
The association of other collagen vascular diseases with pulmonary hypertension is more widely recognized. The incidence of pulmonary hypertension in patients with progressive systemic sclerosis is 33 percent and in those with the CREST variant, the incidence increases to approximately 50 percent. The pulmonary vascular changes involve the small-and medium-sized pulmonary arteries and arterioles. These changes may range from intimal proliferation with narrowing of the vessel to almost complete obliteration of the lumen. Pulmonary vascular lesions also occur in patients with progressive systemic sclerosis who have no evidence of pulmonary hypertension, suggesting that the vascular lesions are the cause rather than the result of pulmonary hypertension.