Hardening of the arteries, or atherosclerosis, causes plaque to form on the inside of blood vessels, and when the plaque ruptures, fragments flow through blood vessels until they stop and form a blockage. When the fragments reach the brain to form a blockage, stroke results, according to the American Stroke Association.
People who consume triglycerides at a high level and develop high cholesterol damage the endothelium, which is the inner lining of the artery. High blood pressure also causes this type of damage, and once the harm begins, the plaque from atherosclerosis begins to develop. Calcium, platelets, cholesterol, fat and debris starts gathering in the walls of the artery. Fat builds up around these objects, which start to form connective tissue. Taken together, this buildup is plaque, and it affects medium- and large-sized arteries, states the American Stroke Association.
Eventually, the plaque becomes fragile, and pieces break off. Some end up dissolving harmlessly, but if they form a clot, and the clot hits a blood vessel that goes to the heart, a heart attack occurs. If the clot blocks a vessel feeding the brain, the result is a stroke. The loss of blood to the brain ends up causing damage that takes anywhere from weeks to years in terms of recovery, as stated by the American Stroke Association.