From the point of view of pulmonary vascular pathology, patients with transposition of the great vessels fall into two main groups, depending on whether or not there is pulmonic stenosis. In the absence of this additional anomaly, which was found in about 10% of our series, the pulmonary arteries are apparently subjected to abnormally high pressure from birth or perhaps even before that. Although measurements of pulmonary pressure and blood flow in infants with transposition are scarce, those available indicate that pulmonary hypertension is the rule. When surgical treatment is to be considered, the altered condition of the pulmonary vessels in response to hypertension is one aspect of the disease that must be taken into account. The present study attempts to quantitate thickening of the small pulmonary arteries in transposition by comparison with normal controls of the same ages.
Material and Methods
Consecutive autopsies at the University of Minnesota Hospitals,