Embolic strokes are caused by clots forming in other parts of the body, breaking free and traveling to the brain, blocking an artery. An embolic stroke is classified as an ischemic stroke, a stroke caused by a blocked vessel. The infarcted, or blocked, artery starves that portion of the brain of blood and oxygen. Brain cells become damaged, and cell death occurs if treatment is not quickly forthcoming.
High Cholesterol
Cholesterol is a soft, waxy substance found in the bloodstream and all cells. According to the National Stroke Association, it is necessary for the formation of cell membranes, vitamin D and some hormones. High levels of LDL, the so-called "bad" cholesterol, builds up in the arteries as plaque and can clog an artery. Plaque can also be dislodged and carried to the brain, blocking an artery causing stroke.
Carotid Stenosis
The American Stroke Association reports that approximately 10 percent of strokes are caused by underlying atherosclerotic stenosis of the carotid artery, a narrowing of the main artery in the neck. Plaque or atherosclerotic debris is thrown into the bloodstream and lodges in a blood vessel of the brain, blocking flow to cells, causing stroke.
Carotid Dissection
A tear or breakdown in the wall of the carotid artery can allow blood to flow between the walls of the artery, narrowing the opening of the vessel leading to stroke. It can be caused by some drugs, attempted strangulation, cerebral angiography, hyperextension of the neck or chiropractic manipulation. It usually occurs in adults under 40.
Fibromuscular Dysplasia
Wake Forest University Baptist Medical Center describes fibromuscular dysplasia, or FMD, as an interruption of blood flow to the brain due to the ongoing destruction of the brain's blood vessels. A hereditary disease mainly affecting women over 50, FMD shows increased areas of muscle and scar tissue alternating with destroyed tissue on the artery walls, narrowing the vessel opening leading to stroke.
Cardiogenic Embolism
A blood clot, or embolus, formed in the heart can dislodge due to atrial fibrillation, travel through the bloodstream and block an artery in the brain. If blood is unable to flow for longer than a few seconds, the result is cell tissue death from lack of blood and oxygen, causing permanent damage and stroke.
