ARTERIAL DISEASE (CIRCULATION PROBLEMS)
The arteries carry blood from the heart and distribute it to the body. The blood carries oxygen and nutrients which are necessary for function and healing of the body. If an artery becomes blocked, that part of the body may have problems with function and healing. If the blood flow is completely cut off, the body part will die. This can happen to any part of the body - the brain, the heart, the kidneys, and the legs are the parts most commonly affected. In the brain, blocked arteries cause strokes; in the heart, angina or heart attack; in the kidneys, high blood pressure or kidney failure; and in the legs, poor blood flow can cause pain, ulcers, or gangrene.
Arteries can become blocked in several ways. The most common are: atherosclerosis, blood clots, and injuries.
Atherosclerosis (hardening of the arteries, arteriosclerosis) occurs when deposits of cholesterol and scar tissue form inside arteries; these "plaques" cause narrowing, and eventually blockage of the artery. Atherosclerosis normally occurs with age, but is worse in some families, in smokers, and in diabetics. Smoking is the most common preventable cause of atherosclerosis. Smoking causes damage to the lining of the arteries by causing them to constrict, by increasing the blood pressure, and by a toxic effect of the nicotine on the lining of the artery. This damage speeds up the development of the plaque. Certain spots in the arterial system are especially susceptible to plaque development; these are the carotid arteries in the neck, which supply blood to the brain; the coronary arteries which supply blood to the heart muscle; the renal arteries which supply blood to the kidneys, and the iliac and femoral arteries which supply blood to the legs.
Blood clots can cause sudden blockages in arteries. In most cases, these clots form in damaged hearts, and then break off and travel through the arteries, stopping whenever a narrow spot is reached. Small blood clots may pass all the way to the feet or fingers; large blood clots may stop the blood flow to the entire brain, or an arm or leg. Sudden blockages are catastophic; if nothing is done, the body part will die. The more gradual blockage caused by atherosclerosis is not as dramatic, because the body has time to develop other sources of blood supply which bypass the blocked area; these are called "collateral vessels". Sometimes, an artery can be completely blocked in this gradual way without causing any symptoms, because the collateral blood flow is so good.
Injuries to arteries can occur from auto accidents or gunshot or stab wounds. Usually there is bleeding, but there may also be blockage of blood flow. Since this occurs suddenly, without a chance for adaptation, it is usually devastating and permanent loss of the body part may occur if blood flow is not restored.
Treatment for arterial blockages or injuries is important if the blockage is causing problems. Usually, diagnosis of the blockage requires an x-ray study called an arteriogram, in which dye is injected into the artery. The dye shows up on the x-ray and gives the surgeon a road-map of the artery and the area of blockage. Sometimes an ultrasound test can be used instead of an arteriogram, but the arteriogram is the most accurate way to make the diagnosis.
There are several possible ways to deal with a blocked or injured artery. Some atherosclerotic plaques can be dilated using a balloon catheter. The plaque is not removed, but simply cracked and stretched using the balloon. More severe blockages usually require operation, which may involve either cleaning out the artery by removing the blood clot or plaque, or bypassing the blocked section of the artery using a section of the patient's own vein or a plastic graft. In general, plastic grafts do not work as well as veins. The decision about whether to operate, and what type of procedure to perform depends on the patient's symptoms and the location and type of blockage. General and vascular surgeons are trained specifically to make these decisions.
