The Third Major Cause of Cvd

The Third Major Cause of CVD

Stroke is a disease that affects the arteries leading to and within the brain. It is the No. 3 cause of death in the United States, behind diseases of the heart and cancer. A stroke occurs when a blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot or bursts. When that happens, part of the brain cannot get the blood (and oxygen) it needs, so it starts to die. About 795,000 (which 185,000 are recurrent events) people suffer a stroke in the United States each year, and of these, about a quarter die. Just as the heart muscle needs an adequate blood supply, so does the brain. Any disturbance in the proper supply of oxygen and nutrients to the brain can pose a threat. There are three main types of stroke, each affecting blood flow in the brain in a different way. (Page, 286) (
Stroke can be caused by a clot obstructing the flow of blood to the brain (called an ischemic stroke or cerebrovascular occlusions). An occlusion is a clot that forms within an artery called a thrombus, or by a clot that travels from another part of the body to the brain called an embolus (causing more than 88 percent of all strokes). The portion of the brain deprived of oxygen and nutrients can literally die. Another type of stroke is caused by a blood vessel rupturing and preventing blood flow to the brain (called a hemorrhagic stroke or cerebral hemorrhage). Damaged, brittle arteries can be especially susceptible to bursting when a person has hypertension. The third type is a TIA (transient ischemic attack or cerebral aneurysm), or "mini stroke", is caused by a temporary clot. An aneurysm is a ballooning or out pouching on a weakened area of an artery. The development of aneurysms is not fully understood, although there seems to be a relationship between aneurysms and hypertension. A stroke will result when a cerebral aneurysm bursts. (Page, 287) (
            Researchers recently...