This is a progressive degeneration of arterial walls,associated with ageing and accompanied by hypertension. In large and medium-sized arteries,the tunica media is infiltrated with fibrous tissue and calcium. This causes the vessels to become dilated,inelastic and tortuous. Loss of elasticity increases systolic blood pressure, and the pulse pressure(the difference between the systolic and diastolic pressure).
When small arteries are involved,their lumen is reduced because of the deposition of a substance called hyaline material,which also reduces the elasticity of the vessel wall. Because these arteries are the main determinants of peripheral resistance,this narrowing increases peripheral resistance and blood pressure. Damage to small vessels has a disproportionate effect on blood flow,leading to ischaemia of tissues supplied by affected arteries. In the limbs,the resultant ischaemiapredisposes to gangrene, which is particularly serious in people with diabetes.
Senile arteriosclerosis: Is a condition affecting elderly people. Progressive loss of elasticity and reduced arterial lumen lead to cerebral ischaemia and loss of mental function. There may or may not be evidence of hypertension.
