Global and regional ischaemia in left ventricular hypertrophy reactive to hypertension.

Hypertension has two main effects on the heart; it increases afterload, causing left ventricular hypertrophy, and precipitates the risk factor for coronary atherosclerosis. Left ventricular hypertrophy is an independent risk factor, but hypertension is a clustering of cardiovascular risks with many metabolic abnormalities, one of which is the recently described endocrinological Syndrome X (hyperinsulinaemia, resistance to insulin-stimulated glucose uptake, glucose intolerance, high triglyceride levels, low HDL and hypertension, which is apparently unrelated to the cardiological Syndrome X (angina with normal coronary arteries). However, the link between both Syndromes X may be the derangement of microvasculture, particularly endothelial dysfunction of nitric oxide (NO) production.