Vascular stenosis is a term used to describe the narrowing of blood vessels. Most commonly, blood vessel narrowing occurs as a result of atherosclerosis inside arteries, the vessels which carry blood from the heart to supply the body. Atherosclerosis, or hardening of the arteries, is a process in which fat, cells and other substances build up inside artery walls forming what are called plaques. These atheromatous plaques make the walls of an artery harder and thicker, so the blood vessel becomes narrower and less flexible, making it more difficult for blood to flow through. Vascular stenosis typically affects arteries in the brain, heart and legs and, when severe, causes tissue death, resulting in conditions such as strokes and heart attacks.
The abnormal narrowing of arteries caused by atherosclerosis can affect arteries in the legs, particularly those supplying the calf muscles. This can lead to a condition known as intermittent claudication, where, in the early stages, cramping pains are felt in the calves after walking a certain distance. The pain goes away after resting for a few minutes. If the disease progresses, the pain is experienced even while resting and leg ulcers, or even gangrene of the toes and feet, may occur.
Vascular stenosis of arteries in the heart can lead to a condition called angina, where pain is felt in the chest during exercise. Again, resting usually causes the pain to go away within a short time, although there is the potential for an artery to become completely blocked. In this case the pain becomes heavy and persistent, possibly spreading to the arm or neck, and a heart attack takes place, in which an area of heart muscle dies off.
When arteries in the brain are affected by vascular stenosis, this can shut off the blood supply to part of the brain tissue or lead to the rupture of a small blood vessel, with bleeding into the brain. Either of these events results in a stroke, where an area of brain tissue dies off, causing a range of possible symptoms including paralysis, numbness, and problems with speech, sight, movement and balance. Carotid artery stenosis, which is narrowing of the large arteries in the neck, may also reduce the brain's blood supply and lead to a stroke.
If the stenosis becomes severe enough to cause a stroke or heart attack, emergency treatment in the hospital will be required. Prevention is important, and progression of stenosis can be halted and the outlook improved by stopping smoking, losing weight, eating more healthily and exercising more. Medication is available to treat conditions such as angina and intermittent claudication, and surgery is sometimes used to bypass or widen blocked arteries. It is also beneficial to treat any other conditions which tend to make vascular stenosis worse, such as high blood pressure and diabetes.