The carotid bodies in coarctation of the aorta.

The carotid bodies were found to be enlarged at the necropsy of a 61-year-old man with congenital coarctation of the aorta. The enlargement was found to be due to hyperplasia of the sustentacular (type II) cells and considered to be a response to systemic hypertension. The proliferation of these cells had compressed the small remaining cores of chief (type I) cells which contain catecholamines and peptides. This case is illustrative of the fact that the carotid bodies may enlarge in some forms of congenital heart disease. The histological changes in the glomic tissue in any one type of congenital cardiac anomaly appear to be related to the nature of the underlying physiological disturbance. Thus the raised intravascular pressure in the upper part of the body in coarctation of the aorta appears to lead to hyperplasia of sustentacular cells.