Arteriosclerosis/Atherosclerosis
Clogged plumbing
Arteriosclerosis, the condition often called hardening of the arteries, is a general term for several conditions in which the wall of an artery becomes thicker and less elastic than usual. The most common form of arteriosclerosis is atherosclerosis in which fatty material -- predominantly cholesterol -- accumulates on artery walls. Your doctor may refer to arteriosclerosis as vascular disease.
Atherosclerosis affects large and medium-sized arteries and is a slow, progressive disease that may start in childhood. In some people, this disease progresses rapidly in their 30s, while others don't have any problems until they reach their 50s or 60s. Collectively, the effects of atherosclerosis on the brain, heart, kidneys, and other vital organs are the leading cause of death and disease in the United States and most western countries. While it can occur anywhere in the body, atherosclerosis is especially common in the arteries leading to the heart and brain and can lead to heart attack or stroke.
Pronunciation
are-tee-rio-skle-ROH-sis
Synonyms
- Coronary artery disease (CAD)
- Coronary heart disease
- Carotid artery disease
- Peripheral vascular disease
Detailed Description
To some extent, arteriosclerosis is a natural part of aging, but a number of lifestyle choices can dramatically affect the onset and severity.
In atherosclerosis, for example, fatty substances -- cholesterol, cellular waste products, calcium, and fibrin (a clotting material in the blood) -- deposit on the inner lining of an artery. The innermost layer of the artery becomes thickened by these accumulating cells and surrounding material. The resulting build-up, called plaques or atheromas, over time may partially block the blood's flow through an artery, thus decreasing the oxygen supply reaching your internal organs. Affected arteries lose their elasticity and narrow as the plaque deposits grow. Coronary atherosclerosis is the cause of coronary artery disease. People with coronary artery disease (narrowed coronary arteries) may experience angina pectoris (chest pain) or discomfort caused by insufficient oxygen supply to the heart muscle.
In time, the plaques also collect calcium deposits, causing the plaques to become brittle, and increasing the likelihood of rupturing. When a rupture occurs, blood may flow in and make the plaque larger so that it narrows the artery even more. A ruptured plaque may trigger the formation of a blood clot (thrombus). The clot may further narrow or even block the artery, or it may detach and float freely in the blood until it gets stuck in a small vessel. The end result is usually serious. Blockage of the arteries supplying blood to the heart can cause heart attack. Blockage of the arteries supplying blood to the brain can cause stroke. Blockage of the arteries supplying blood to the extremities can cause gangrene.
Symptoms often don't appear until the atherosclerosis reaches an advanced stage, at which point it becomes harder to treat. The best approach is prevention -- avoiding the numerous risk factors under your control, including diet, smoking, and exercise.
How Common Is Arteriosclerosis?
Arteriosclerosis is very common in the United States. According to the Centers for Disease Control (CDC), cardiovascular disease, principally heart disease and stroke, accounts for 42% of all deaths nationwide, for both men and women among all racial and ethnic groups. The CDC estimates that one in four Americans has cardiovascular disease.
Theoretical Causes
The actual mechanism by which arteriosclerosis begins is unknown, but researchers have proposed two hypotheses to explain what happens: the lipid hypothesis and the chronic endothelial injury hypothesis. The two are not mutually exclusive and are probably related.
The lipid hypothesis postulates that elevated low-density lipoprotein (LDL, or "bad" cholesterol) in the blood causes the LDL to penetrate the artery wall where it not only promotes accumulation and the development of plaques, but also oxidizes and damages the artery wall.
The chronic endothelial injury hypothesis postulates that damage to the arterial wall by various processes causes the clotting agents in blood to attach to the artery wall and initiate the formation of fibrous plaque.
Although the actual mechanism is still the subject of research, the risk factors of arteriosclerosis are well documented.
Risk Factors
Some of the key risk factors for arteriosclerosis are associated with lifestyle, while others are hereditary:
- Smoking
- Diet high in fat and cholesterol
- Family history of premature arteriosclerosis or heart attacks
- Obesity
- High blood pressure
- Diabetes mellitus
- Elevated low-density lipoprotein (LDL, or "bad") cholesterol
- Decreased high-density lipoprotein (HDL, or "good") cholesterol
- Elevated levels of fats (triglycerides)
- Sedentary lifestyle
- Increasing age
- Being a man
- Being a postmenopausal woman
- Family history of high cholesterol
- Elevated homocysteine levels in the blood (a genetic condition that may be associated with vascular injury and predispose the vessels to atherosclerosis)
- Chlamydia pneumoniae infection (some experts believe it may contribute to vascular damage and inflammation that could lead to atherosclerosis)
Risk factors are traits or behaviors that may make you statistically more likely than others in the general population to have a certain condition. They are not necessarily "causes" of the condition.
Symptoms
Arteriosclerosis usually has no symptoms in the early stages and may remain silent in the advanced stages as well. Signs and symptoms that do show up are usually associated with the secondary conditions caused by arteriosclerosis. The most common one is angina pectoris (chest pain), which is caused by a lack of oxygenated blood flow to the heart muscle. You should also be aware of the following:
- Physical exercise, large meals, stress, or exposure to cold can cause angina and its episodes of tightness, heaviness, pressure, and varying intensity of pain in the chest region. Angina can also occur abruptly with no apparent cause ("unstable" angina).
- Some people feel the pain of angina in the face, neck, and other upper-body regions, particularly the left arm.
- Short episodes (less than 24 hours) of dizziness, one-sided weakness, difficulty speaking, or visual changes (collectively called transient ischemic attacks, or TIAs) signal a problem with blood flow to the brain and the risk of stroke.
Cool feet, pain in the back of the thigh, hair loss on your legs, shiny skin on your shins, and red color in your legs and feet when they hang down are all signs that the arteries in your legs may be blocked. If the arteries of your legs are affected, the first symptom is a painful, aching, cramping, or tired feeling in leg muscles when you walk, and the pain is worse when you walk quickly or walk uphill. The pain -- which you might feel in your calf, foot, thigh, hip, or buttocks -- goes away when you stop walking. As the condition progresses and the arteries are narrowed even more, the distance you can walk without pain decreases and in severe cases the muscles may ache even when you're resting.
Conditions That May Be Mistaken for Arteriosclerosis/Atherosclerosis
If your arteries are narrowed due to plaque buildup, you have arteriosclerosis. However, chest pain and shortness of breath could be caused by other conditions:
- Gastrointestinal disorders such as peptic ulcer, indigestion, hiatus hernia, gallbladder disease, and spasms or inflammation of the esophagus
- Chronic shortness of breath (dyspnea)
- Blood clot in the lung, pneumonia, or pleurisy
- Aortic aneurysm: injury of the tissue in the wall of aorta (the major artery carrying blood out of the heart)
- Inflammation of the membrane around the heart (pericarditis)
- Inflammation of or damage to the ribs
- Disease of the spinal nerve roots (radiculopathy)
- Psychological disorders due to panic or anxiety
- Cervical or thoracic spine disease
How Is Arteriosclerosis/Atherosclerosis Diagnosed?
Checking your blood-cholesterol level should be part of your routine physical. Men over 45 and women over 55 should have a cholesterol test as frequently as their doctors suggest. If you have symptoms (such as chest pain or heart attack) that your doctor suspects stem from arteriosclerosis, further testing is required to confirm the diagnosis:
- Your medical history and physical exam
- Blood tests
- Electrocardiogram (EKG or ECG)
- Exercise testing
- Various methods of imaging
Laboratory Work
Laboratory blood tests that detect levels of triglycerides, cholesterol, LDL, and HDL are usually helpful to the diagnosis.
Specific Tests
Special tests are performed to confirm arteriosclerosis by evaluating the cardiovascular system.
- Electrocardiogram (EKG) measures electrical activity of the heart, which may be abnormal if there is diminished blood flow to the heart.
- Exercise stress test that measures blood pressure, heartbeat, and breathing rate as well as an EKG, during exercise. This test can show if not enough oxygen is reaching the heart during exercise.
Imaging
Imaging allows your physician to locate the narrowed artery, which is helpful in determining which therapy is best for your condition.
- Coronary arteriography: A doctor guides a thin plastic tube through an artery in your arm or leg and into the coronary arteries, and then injects a liquid dye visible in x-rays through the catheter. High-speed X-ray movies show the liquid as it flows through the arteries. Doctors can identify blockages in the arteries by tracing the liquid's flow.
- Radionuclide scintigraphy: an imaging technique that involves the use of radioactive elements to demonstrate blood flow in the heart.
- Stress echocardiography: a diagnostic procedure that studies the structure and motion of the heart.
- Stress thallium: imaging test to measure cardiac function and blood flow.
- Carotid ultrasound: evaluates the arteries leading to the brain to look for plaques and narrowing.
Supplements
- Vitamin E: Two landmark Harvard studies -- one involving men, the other, women -- showed that vitamin E (100 IU/day) substantially reduces the risk of atherosclerosis. Compared with those who did not take the vitamin, the people who did suffered significantly fewer heart attacks -- 37% less in men, 41% less in women. Vitamin E is a powerful antioxidant that also helps treat atherosclerosis. [1,2]
- Vitamin C: A major antioxidant, Vitamin C also helps prevent and treat atherosclerosis.
- B vitamins: These help reduce blood levels of homocysteine, a recently identified risk factor for atherosclerosis and heart attack. Researchers in Northern Ireland gave supplemental B vitamins to 101 men with high homocysteine levels. Eight weeks later, their homocysteine levels had dropped 28%, significantly reducing their atherosclerosis and risk of heart attack. [3] Nutrition experts suggest 3 mg of vitamin B-6 and 400 mcg of folic acid.
- Fish oil: you can get the omega-3 fatty acids found in cold-water fish without eating them if you take fish-oil supplements. In addition to possibly preventing atherosclerosis, fish oil may increase the effectiveness of angioplasty and coronary artery bypass surgery. [4,5]
Relaxation
- Meditation is a key element of the Ornish program, and other studies also show its value. At the State University of New York-Buffalo, researchers tested the exercise ability of 21 people with heart disease, and then taught them transcendental meditation (TM). Eight months later, they could exercise 15% more strenuously before experiencing chest pain, indicating less atherosclerosis and a decreased risk of heart disease. [6]
A great deal of research shows that the broad range of relaxation therapies helps prevent and treat atherosclerosis. Practice whatever appeals to you: meditation, deep breathing, massage, hot baths, imagery/visualizations, progressive muscle relaxation, or self-hypnosis. - Cherish your friends and family. The Ornish program includes a support group, since many studies show that social support helps prevent and treat heart disease. New York researchers followed more than 1,000 heart-attack survivors for four years. Among those who lived alone, 16 had a recurrence. But among those who lived with a spouse, the figure was only about half that. [7]
Herbs
- Garlic: Powerful medicine against atherosclerosis and heart attack, garlic reduces cholesterol and blood pressure, and makes blood less likely to form the clots that can cause heart attacks. [8] Commission E, the German panel of doctors, pharmacists, and herbalists that judges the safety and effectiveness of herbal medicines for the German government, recommends one to four garlic cloves a day.
- Willow bark: Doctors recommend low-dose aspirin to prevent the internal blood clots that trigger heart attacks. You can gain the same benefit from a cup of willow-bark tea. [9] Willow bark contains salicin, aspirin's herbal precursor. A half-teaspoon of willow bark contains about 100 mg of salicin, enough to provide aspirin's benefits.
1 Rimm, E.B., et al. "Vitamin E Consumption and Risk of Coronary Heart Disease in Men," New England Journal of Medicine 328:1450, 1993.
2 Stampfer, M.J., et al. "Vitamin E Consumption and Risk of Coronary Disease in Women," New England Journal of Medicine 328:1444, 1993.
3 Woodside, J., et al. "Effect of Vitamin Supplementation on Cardiovascular Risk," Journal of Inheritable and Metabolic Diseases 19(Suppl 1):26, 1996.
4 Eritsland, J., et al. "Effect of Dietary Supplementation with N-3 Fatty Acids on Coronary Artery Bypass Graft Patency," American Journal of Cardiology 77:31, 1996.
5 Gapinski, J.P., et al. "Preventing Restenosis with Fish Oils Following Coronary Angioplasty: A Meta-Analysis," Archives of Internal Medicine 153;1595, 1993.
6 Zamarra J.W., et al. "Usefulness of TM in the Treatment of Patients with CAD," American Journal of Cardiology 77:867, 1996.
7 Case, R.B., et al. "Living Alone after MI: Impact on Prognosis," Journal of the American Medical Association 267:515, 1992.
8 ,9 Duke, J., The Green Pharmacy, Emmaus, PA: Rodale Press, 1997.
Preventing Atherosclerosis
The best treatment for atherosclerosis is prevention. Prevention focuses on eliminating controllable risk factors:
- Lower blood cholesterol levels with diet and/or medication
- Lower blood pressure
- Stop smoking
- Lose weight
- Begin an exercise program
- Reduce stress
Once signs of arteriosclerosis appear, most of the same preventive measures are still recommended for slowing the progress of artery hardening.
Self-Care Measures
- If you smoke, quit. Smoking is a major risk factor for atherosclerosis, and quitting quickly reduces your risk.
- Eat an ultra low-fat diet -- it's a key element of the only program ever shown to reverse atherosclerosis. Pioneered by Dean Ornish, M.D., of the Preventive Medicine Research Institute in Sausalito, Calif., the program has five components:
- Vegetarian diet containing just 10% fat (compared to the average American's 35%)
- Daily exercise, like walking
- Meditation
- Yoga
- Weekly support-group meetings
In a series of three landmark studies, Ornish showed that people who embrace his program enjoy progressively increasing blood flow through their coronary arteries, a feat that drugs and surgery cannot match. As atherosclerosis decreases, so does risk of heart attack. - Eat more plant foods. Even if you don't adopt the entire Ornish program, it's a good idea to limit meats and eat more plant foods, which include fruits, vegetables, beans, and whole grains. In one study, Harvard researchers followed 44,000 middle-aged men for six years. As the men's plant-food consumption increased, their risk of atherosclerosis decreased. Compared with those who ate the fewest plant foods, those who ate the most enjoyed substantial protection from heart attacks. Plant foods are high in antioxidant nutrients, which prevent the cell damage at the root of atherosclerosis.
Plant foods are central to the "Mediterranean diet" of people in Spain, Italy, and Greece. People there consume a good deal more fat than the Ornish-program limit, but it's mostly monounsaturated olive oil, the heart-healthiest fat, as opposed to the saturated fat found in meat, the kind that leads to heart disease. Several studies show that the Mediterranean diet helps prevent heart attack. And if you've survived a heart attack, this diet can prevent a recurrence. In one study, French researchers told 605 heart-attack survivors to eat either a diet heavier in saturated fat or a Mediterranean-style diet. During five years of follow-up, the Mediterranean group had 72% fewer second heart attacks. - Try drinking tea. Several recent studies have shown that, like plant foods, tea is high in the antioxidants that prevent atherosclerosis.
- Eating cold-water fish, notably salmon, may also help prevent and treat atherosclerosis. Cold-water fish are high in omega-3 fatty acids, which help prevent the arterial damage that leads to heart attack.
- Drink a little red wine. Many studies show that modest alcohol consumption (about one drink a day) raises HDL (or "good") cholesterol, the kind that reduces risk of atherosclerosis. In addition, red wine contains extra antioxidants that further reduce risk. Some people shouldn't drink at all, including current or former alcoholics, those with a family history of alcoholism, pregnant women, and people with liver disease. But if you can drink, a little alcohol, especially red wine, can help prevent atherosclerosis and heart attack.
- Get more exercise. An enormous amount of research shows that physical activity reduces risk of atherosclerosis. In one study, Harvard researchers analyzed the results of more than a dozen studies that correlated exercise and risk of death from heart disease. Compared with sedentary individuals, people who got regular exercise had just half the risk.
The Ornish program encourages walking and yoga, but any regular, moderate exercise helps. Exercise is also a standard part of post-heart-attack rehabilitation.
Websites & Organizations
Agency for Health Care Policy and Research (AHCPR)
American Heart Association
7320 Greenville Ave.
Dallas, TX. 75231
Phone: 214-750-5300
Cardiac Health Web
Heart Health
Heartline
9500 Euclid Ave., Room EE-37
Cleveland, OH 44195
Phone: (800) 478-4255
Heartmates, Inc.
PO Box 16202
Minneapolis, MN 55416
Phone: 800-9HM-3331 (800-946-3331)
Email:heartmates@outtech.com
National Heart, Lung, and Blood Institute, Information Office
P.O. Box 30105
Bethesda, MD 20892-0105
Phone: 301-251-1222
New York Online Acess to Health
Sources for This Article
Books
Balch, James F. and Balch, Phyllis A. Prescription for Nutritional Healing. Garden City Park, NY: Avery Publishing, 1997.
Bennett, J. Claude and Plum, Fred. Cecil Textbook of Medicine, eds. Philadelphia: W. B. Saunders, 1996.
Duke, J. The Green Pharmacy, Emmaus, PA: Rodale Press, 1997.
Fauci, Anthony J., et. al. Harrison's Principles of Internal Medicine, eds. New York: McGraw-Hill, 1998.
Hardman, Joel G. and Limbird, Lee E. Goodman and Gilman's The Pharmacological Basis of Therapeutics eds. New York: McGraw-Hill, 1996.
Hurst, J. Willis. Medicine for the Practicing Physician eds. Stamford, CT: Appleton & Lange 1996.
Murray, Michael T. Encyclopedia of Natural Medicine. Prima, 1998.
Noble, John. Primary Care Medicine ed. St. Louis: Mosby, 1996.
Physicians' Desk Reference. Montvale, NJ: Medical Economics Co., 1998.
Rakel, Robert E. Conn's Current Therapy eds. Philadelphia: W.B. Saunders, 1998
Taylor, Robert B. Family Medicine: Principles and Practice. New York: Springer-Verlag, 1998.
Tierney, L.M., McPhee, S.J., and Papadakis, M.A. Current Medical Diagnosis and Treatment eds. Stamford, CT: Appleton & Lange, 1998.
Articles
Austin, MA. "Genetic Epidemiology of Dyslipidaemia and Atherosclerosis." Ann Med. 28(5):459-63. Oct 1996.
Berlin, JA and GA Colditz. "Meta-Analysis of Physical Activity in the Prevention of CHD," Am. J. Epiedmiol, 132:612, 1990.
Case, RB et al. "Living Alone after MI: Impact on Prognosis," JAMA, 267:515, 1992.
Duncan, BB, Metcalf, P, Crouse, JR 3rd, Li, R, Sharrett, AR, Tegeler, C, Tyroler, HA, Heiss, G. "Risk Factors Differ for Carotid Artery Plaque with and without Acoustic Shadowing." Atherosclerosis Risk in Communities Study Investigators. J Neuroimaging. 7(1):28-34. Jan 1997.
Eritsland, J. et al. "Effect of Dietary Supplementation with N-3 Fatty Acids on Coronary Artery Bypass Graft Patency," Am. J. Cardiology, 77:31, 1996.
Fernandez-Ortiz, A, Fuster, V. "Pathophysiology of Coronary Artery Disease." Clin Geriatr Med. 12(1):1-21. Feb 1996.
Fletcher, GF. "The Antiatherosclerotic Effect of Exercise and Development of an Exercise Prescription." Cardiol Clin. 14(1):85-95. Feb 1996.
Frankel, EN. et al. "Inhibition of Oxidation of Human LDL by Phenolic Substances in Red Wine," Lancet, 341:454, 1993.
Gapinski, JP et al. "Preventing Restenosis with Fish Oils Following Coronary Angioplasty: A Meta-Analysis," Archives of Int. Med., 153;1595, 1993.
Hertog, MG, et al. "Dietary Antioxidant Flavonoids and Risk of CHD," Lancet, 342(8878):1007, 1993.
Jenkins, DJ. "Optimal Diet for Reducing the Risk of Arteriosclerosis." Can J Cardiol. 11 Suppl G():118G-122G. Oct 1995.
Ku, A, Nagler, W. "Arteriosclerosis Obliterans. Diagnostic and Nonoperative Treatment Options." Postgrad Med. 98(5):203-4, 207-10, 212. Nov 1995.
Ornish, D. et al. "Can Lifestyle Changes Reverse Coronary Artery Disease?" Lancet, 336:129, 1990.
Raffel, LJ. "The Epidemiology and Genetic Basis of Common Diseases." Pediatr Ann. 26(9):525-34. Sep 1997.
Renaud. S. et al. "Cretan Mediterranean Diet for Prevent of CHD," Am. J. Clin. Nutrition, 61(Suppl): 1360S, 1995.
Rimm, EB et al. "Vegetable, Fruit, and Cereal Fiber Intake and Risk of CHD in Men," JAMA, 275:447, 1996.
Rimm, EB, et al. "Vitamin E Consumption and Risk of Coronary Heart Disease in Men," NEJM, 328:1450, 1993.
Schettlerballot, G. "Arteriosclerosis." Eur J Med Res. 2(6):233-5. Jun 16, 1997.
Stampfer, MJ et al. "Vitamin E Consumption and Risk of Coronary Disease in Women," NEJM, 328:1444, 1993.
Stone, NJ. "The Clinical and Economic Significance of Atherosclerosis." Am J Med. 101(4A):4A6S-9S. Oct 8, 1996.
Woodside, J. et al. "Effect of Vitamin Supplementation on Cardiovascular Risk," J. of Inheritable and Metabolic Dis., 19(Suppl 1):26, 1996.
Zamarra JW et al. "Usefulness of TM in the Treatment of Patients with CAD," Am. J. Cardiology, 77:867, 1996.
"Arteriosclerosis Prevention by Risk Prevention. Symposia Proceedings. January 13, 1996, Munich and March 9, 1996, Nuremberg, Germany. Dedicated to Prof. Dr. med. Peter Schwandt on the Occasion of his 60th Birthday." Eur J Med Res. 2(6):231-74. Jun 16, 1997.