Role of hypertension in ischemic heart disease and cerebral vascular disease in the cynomolgus monkey with coarctation of the aorta.

The role of hypertension in cardiovascular disease was studied in the hypertensive coarcted monkey during the feeding of an atherogenic and nonatherogenic diet. During the 15-month period of observation, half of the hypertensive coarcted monkeys developed cardiovascular disease which included heart failure, ischemic heart disease, stroke, and sudden death. There were no cardiovascular complications in the control normotensive monkeys except for one cholesterol-fed animal. The incidence of ischemic heart disease and sudden cardiac death was higher in monkeys with both hypertension and hypercholesterolemia than in those with hypertension or hypercholesterolemia alone. Postmortem studies revealed that the former monkeys had both hypertensive and atherosclerotic heart disease, whereas the monkeys with hypertension or hypercholesterolemia had either hypertensive or atherosclerotic heart disease. Hypertensive heart disease was characterized not only by hypertrophy of the left ventricle but also by focal myocardial degeneration and fibrosis and by focal thickening and narrowing of the small coronary arteries, particularly the sinus node artery and the atrioventricular node artery. The finding of transmural myocardial infarction in two monkeys with patient coronary arteries suggests a possible role of coronary artery spasm in ischemic heart disease in hypertension. The cerebral vascular complications of hypertension included hypertensive encephalopathy, transient "ischemic" attacks, and hemorrhagic stroke. The complications were associated with severe hypertension and with hypertensive vascular disease or hypertensive and atherosclerotic vascular disease of the cerebral arteries.