Cardiovascular manifestations of mixed connective tissue disease in adults.

To assess the nature and distribution of cardiovascular abnormalities associated with mixed connective tissue disease, we studied 38 patients with overlapping clinical manifestations of systemic lupus erythematosus, progressive systemic sclerosis and polymyositis, and circulating antibodies to nuclear ribonucleoprotein. The protocol included taking a medical history and a physical echocardiogram, and pulmonary function tests. Cardiac catheterization was performed on 17 patients. Postmortem examination was performed on four of the five patients who died during follow-up. Acute pericarditis and/or pericardial effusion was detected in 11 patients (29%) and mitral valve prolapse was identified in 10 patients (26%). Marked intimal hyperplasia of coronary arteries was observed in all four hearts that were autopsied and perivascular and myocardial leukocytic aggregates were present in two hearts. Pulmonary vascular resistance was elevated in 11 of the 17 patients who underwent cardiac catheterization. In summary, cardiovascular abnormalities associated with mixed connective tissue disease include acute pericarditis and/or effusion, mitral valve prolapse, intimal hyperplasia of coronary arteries, perivascular and myocardial leukocytic infiltrates, and pulmonary hypertension.