Arteriolar and capillary remodelling in hypertension.

The major haemodynamic abnormality underlying elevated blood pressure in hypertension is an increase in vascular resistance. The microcirculation is a key site of increased vascular resistance in hypertension. A reduced density of arterioles and capillaries is an important common characteristic of various microvascular beds in many forms of hypertension. This microvascular rarefaction has been observed even in very early stages of the development of hypertension. A hypothesis is discussed for early microvascular rarefaction being the result of genetic and fetal mechanisms of decreased small blood vessel growth.