It is at least partially caused by irreversible damage to organs including kidneys, brain and heart by insufficient blood flow. This is usually defined as a systolic pressure less than 100 mm Hg. Orthostatic hypotension is the temporary dizziness that occurs in elderly people upon suddenly standing up. It is caused by the aging sympathetic system not responding fast enough to the sudden low pressure in the carotid artery. This slow response causes blood to pool briefly in the lower limbs reducing blood delivery to brain.
Acute hypotension is the result of circulatory shock.
This occurs as a result of increased TPR caused by partial blockage of blood vessels. The increased pressure damages arteries which leading atherosclerosis which aggravates the condition further. The increased pressure strains the heart and other organs, notably eyes and kidneys. It is a major cause of death due to heart failure, renal failure and stroke. Blood flow is directed towards muscle and away from the gut and skin.