Muscular pulmonary arteries in chronic obstructive lung disease.

The small muscular pulmonary arteries are thought to be normal in obstructive pulmonary disease despite prolonged hypoxic stimulation to medial thickening. Because measurements on nondistended vessels have considerable variability, we reinvestigated the problem by studying the percentage of wall thickness of distended arteries in lungs taken post mortem from 5 asymptomatic emphysematous patients and 11 symptomatic patients with obstructive pulmonary disease. Vessels in the former patients had normal medial thicknesses. In contrast, we found an elevated mean percentage of wall thickness for vessels between 0.3 and 2.0 mm in diameter of 4.46% +/-1.44% (mean +/-SD) for patients with obstructive airways disease. Obstructive pulmonary disease, therefore, produced medial hypertrophy in small muscular arteries similar to that seen in other conditions associated with chronic hypoxia.