- Facts on Hardening of the Arteries (Atherosclerosis)
- What Causes Hardening of the Arteries?
- What Are the Symptoms of Hardening of the Arteries?
- When Shoud I See a Doctor about Hardening of the Arteries?
- What Exams and Tests Diagnose Hardening of the Arteries?
- What Is the Treatment for Hardening of the Arteries?
- Are There Home Remedies for Arteriosclerosis?
- What Is the Medical Treatment for Hardening of the Arteries?
- What Are the Medications for Arteriosclerosis?
- What Is the Surgery for Hardening of the Arteries?
- Can You Prevent Atherosclerosis?
- What Is the Prognosis for Hardening of the Arteries?
- Hardening of the Arteries (Atherosclerosis) Topic Guide
Facts on Hardening of the Arteries (Atherosclerosis)
Hardening of the arteries (atherosclerosis) is a disorder in which arteries (blood vessels that carry oxygenated blood from the heart to other parts of the body) become narrowed because fat (cholesterol deposits called atherosclerosis) is first deposited on the inside walls of the arteries, then becomes hardened by fibrous tissue and calcification (arteriosclerosis). As this plaque grows, it narrows the lumen of the artery (the space in the artery tubes), thereby reducing both the oxygen and blood supply to the affected organ (like the heart, eyes, kidney, legs, gut, or the brain). The plaque may eventually severely block the artery, causing the death of the tissue supplied by the artery, for example, heart attack or stroke.
When the arteries of the heart (coronary arteries) are affected by arteriosclerosis, the person can develop angina, heart attack, congestive heart failure, or abnormal cardiac rhythms (because of coronary artery disease). When the arteries of the brain (cerebral arteries) are affected by arteriosclerosis, the person can develop a threatened stroke, called transient ischemic attack, or actual death of brain tissue, called stroke.
Hardening of the arteries is a progressive condition that may begin in childhood. Fatty streaks can develop in the aorta (the largest blood vessel supplying blood to both the upper and lower part of the body) shortly after birth. In those people with a familial history of high cholesterol, the condition may worsen rapidly in the early 20s and progressively become more severe in the 40s and 50s.
In the United States, approximately 720,000 heart attacks occur annually. Nearly 380,000 people die annually from coronary heart disease.
The incidence of coronary heart disease in the Far East is significantly lower than in the West. Possible genetic reasons for this difference are not clearly defined. However, the role of the Western diet, lack of exercise, obesity, and other environmental factors may be responsible for contributory factors for the differences.
What Causes Hardening of the Arteries?
The exact cause of arteriosclerosis is not known; however, risk factors for the development and progression of arteriosclerosis have been identified. The risk factors can be divided into factors that can be changed and those that cannot.
Risk factors that can be changed include the following:
- High blood pressure
- High blood cholesterol levels, especially low-density lipoprotein cholesterol or LDL cholesterol (bad cholesterol)
- Cigarette smoking
- Lack of exercise
- Western diet, with excessive saturated fat in meat, dairy products, eggs, and fast foods (the McDonald's Syndrome) with inadequate fruits, vegetables, and fish
Risk factors that cannot be changed include the following:
- Advancing age
- Being male (Women are at lower risk only until menopause.)
- Having a close relative who has had heart disease or stroke at a relatively young age (bad genes, especially with familial hypercholesterolemia [increased cholesterol levels]).
- Race: African Americans have excessive and early degree of high blood pressure, leading to premature stroke, heart attack, congestive heart failure, and death.
What Are the Symptoms of Hardening of the Arteries?
Arteriosclerosis often does not cause symptoms until the lumen of the affected artery is critically narrowed or is totally blocked.
The symptoms of arteriosclerosis are highly variable and can range from no symptoms (in the early stage of the disease) to heart attack or stroke (when the lumen of the artery is critically blocked). Sudden cardiac death can also be the first symptom of coronary heart disease.
Symptoms also depend on the location of the arteries affected by arteriosclerosis.
- If the coronary arteries supplying the heart are affected, the person may develop chest pain, shortness of breath, sweating, and anxiety. The specific chest pain (angina), or inadequate blood flow to the heart muscle, generally occurs with exertion and disappears at rest. Classically, angina is a tight, heavy, oppressive sensation in the middle of the chest. Rarely, angina can occur at rest and signifies a more unstable plaque and possibly a threatened heart attack.
- Many types of chest pain are not angina, including sore muscles and ligaments in the chest wall; injured lungs surrounding the heart; and a raw, sore esophagus, which runs down through the chest behind the heart.
- If the carotid or vertebral arteries supplying the brain are affected by arteriosclerosis, the person may develop numbness, weakness, loss of speech, difficulty swallowing, blindness, or paralysis of a part of the body (usually one-half of the body).
- If the arteries supplying the legs are affected (see Peripheral Vascular Disease), the person may have severe pain in the legs. The pain typically comes when a person is walking and goes away when he or she stops walking (intermittent claudication). When the disease is severe, the pain may come on at rest and/or at night. If the skin breaks down, the wound may become infected and never heal, potentially leading to amputation.
- If the arteries supplying the kidneys are affected, the person can have symptoms of high blood pressure or may develop kidney failure.
When Shoud I See a Doctor about Hardening of the Arteries?
One should consult a health care provider if there are risk factors for atherosclerosis (arteriosclerosis), especially if one has any unexplained symptoms suggesting blocked arteries.
If a person has been diagnosed with atherosclerosis of the coronary arteries, a healthcare provider should be consulted before beginning any exercise program.
What Exams and Tests Diagnose Hardening of the Arteries?
The health care provider may request the following tests:
- Physical examination to include blood pressure in both arms, height, and weight with a calculated body mass index (BMI), and a measured waist circumference.
- Bruits or turbulence over blocked arteries in the neck, abdomen, and legs may sometimes be heard with a stethoscope. Blocked arteries in the heart are not audible.
- Lipid profile to check levels of total blood cholesterol; low-density lipoprotein (LDL), or bad cholesterol; high-density lipoprotein (HDL), or the good cholesterol; and triglycerides, especially in people with diabetes.
- Blood glucose measurement to screen for diabetes, especially if the person is obese, has high blood pressure, high lipids, and/or family history of diabetes.
- Resting ECG records the rate and regularity of the heartbeat. It may show evidence of a previous heart attack. A person with multiple severely blocked arteries may have an absolutely normal resting ECG.
- Stress ECG is an exercise on a treadmill or a stationary bicycle with the person's ECG, blood pressure, and respiration continuously recorded. In persons who have atherosclerosis, this test may show evidence of decreased blood supply to the heart created by the increased demand for blood and oxygen by the exercise. If the patient is not able to exercise, a chemical stimulation test can be performed.
- Nuclear stress test involves the administration of a radioactive substance into the bloodstream before taking images of the heart muscle (at rest and immediately after exercise). The images give an idea about the perfusion of the heart muscle. If a person has coronary artery disease, blood supply decreases with exercise in the area supplied by the blocked artery. The test is more sensitive than a stress ECG, and it can better predict which blocked artery is involved. This test is also much more expensive than an ECG.
- Echocardiogram is a test in which moving images of the heart can be visualized on a screen with an ultrasound probe. If an area of the heart has become weakened as a consequence of a heart attack, the damaged muscle of the left ventricle can be detected and the amount quantified. Echocardiography also reveals problems with the heart valves, any fluid around the heart, congenital connections between the 2 sides of the heart, and estimates pressures inside the heart.
- Exercise echocardiography is an alternative to a nuclear stress test. Echo only analyzes the movement of the left ventricle. When a lack of blood flow occurs, the ischemic area stops working. Then, with rest and resolution of ischemia, the muscle starts moving again.
- Angiography of the affected artery is advised if the symptoms are disabling and/or if the above tests suggest a high probability of significant coronary artery disease. This is an invasive procedure, performed in a catheterization laboratory by a cardiologist. A special radiopaque dye is injected into the arteries through a thin tube or catheter, which is inserted into the body under local anesthesia, usually from the groin region. Serial x-ray films are then taken to visualize the arteries for any narrowing. This is still the most specific test to evaluate coronary artery disease.
What Is the Treatment for Hardening of the Arteries?
The goals of treatment of arteriosclerosis are to reduce the symptoms and prevent the progression of the disease so as to prevent blockage of the lumen of the affected arteries. Treatments include
- lifestyle changes,
- angioplasty, and
Are There Home Remedies for Arteriosclerosis?
If a person has arteriosclerosis, he or she will need to make the following lifestyle changes:
- Eat food that has low saturated fat and low cholesterol.
- Restrict the salt-intake in the diet if one has high blood pressure.
- Increase the consumption of food that has high fiber content (vegetables and fruits).
- Eat fish at least twice a week.
- Quit smoking.
- Lose weight if overweight.
- Exercise under the supervision of a health care provider.
- If the patient has elevated blood glucose, he or she will have to regularly monitor blood glucose levels and glycosylated hemoglobin (HbA1c) levels.
What Is the Medical Treatment for Hardening of the Arteries?
The goal of treating atherosclerosis is to restore as much blood flow as possible to the affected areas. This goal can be achieved by reducing risk factors that can be changed through steps such as the following:
- Taking drugs to normalize blood pressure, if blood pressure is high. (See High Blood Pressure for more information.)
- Taking drugs to normalize blood sugar levels, especially for people with diabetes. (See Diabetes for more information.)
- Taking drugs to lower lipid levels, if levels are high. These drugs help lower LDL cholesterol levels and triglycerides and raise HDL cholesterol levels. Statins are the most commonly used lipid-lowering drugs because of powerful clinical trial data results over the past 11 years. (See Understanding Cholesterol-Lowering Medications.)
- Smoking cessation. The risks of cigarette smoking are reduced rapidly and significantly with smoking cessation. The relative risk is so significant that the incidence of coronary heart disease in people who have recently quit smoking is similar to that of people who have not smoked within two years. Cigarette smoking decreases the level of good cholesterol (high-density lipoprotein cholesterol or HDL cholesterol) and increases the level of bad cholesterol. Smoking is even more dangerous for people who already have a high risk of heart disease. It raises the level of carbon monoxide in the blood, which may increase the risk of injury to the lining of the arterial wall, thereby facilitating plaque formation. Smoking constricts arteries already narrowed by the plaque, further decreasing the amount of blood reaching the cells.
- Exercise, weight loss, and dietary changes are also helpful in preventing the progression of atherosclerosis.
- Aspirin should be routinely used by persons with established arteriosclerosis of any arteries and in individuals at high risk (by risk factor analysis) for arteriosclerosis. Aspirin inhibits sticky platelets floating in the blood from starting a blood clot, and final blockage of a narrowed, plaque-filled artery.
What Are the Medications for Arteriosclerosis?
Medications used to lower blood cholesterol levels are broadly divided into five categories. For details of cholesterol-lowering medications, see Understanding Cholesterol-Lowering Medications.
- Statins: Commonly used agents include atorvastatin (Lipitor), fluvastatin (Lescol), lovastatin (Mevacor, Altocor), pravastatin (Pravachol), simvastatin (Zocor), and rosuvastatin (Crestor). The statins inhibit an enzyme, which controls the rate of cholesterol production in the body. See Statins and Cholesterol. The pill is taken once a day and is usually started after a trial of diet and exercise has failed.
- Bile acid sequestrants: Cholestyramine (Questran, Questran Light, Prevalite, LoCholest), colestipol (Colestid), and colesevelam (Welchol) are commonly prescribed bile acid sequestrants. These drugs bind with cholesterol-containing bile acids in the intestines, which are then excreted in the stool. Thus, they reduce the absorption of ingested cholesterol from the intestine. They may cause diarrhea and many patients do not tolerate them.
- Cholesterol absorption inhibitors: Ezetimibe (Zetia) selectively reduces the absorption of cholesterol. It is often combined with statins.
- Nicotinic acid or niacin: A water-soluble B vitamin that significantly increases HDL cholesterol (good cholesterol) and reduces LDL cholesterol (bad cholesterol). Flushing is the most common bothersome side effect.
- Fibrates: Commonly prescribed fibrates include gemfibrozil (Lopid) and fenofibrate (Tricor). They are primarily effective in lowering triglyceride and bad cholesterol levels and, to a lesser extent, in increasing good cholesterol levels.
What Is the Surgery for Hardening of the Arteries?
Balloon angioplasty: In this procedure, a balloon-tipped catheter is used to open blocked or narrowed arteries. The catheter (thin tube) is inserted into the body through a blood vessel in the groin region and pushed all the way up and into the blocked artery. When the narrowed part of the artery is reached, the balloon is inflated to press the plaque against the arterial wall so that the lumen of the affected artery increases in diameter, therefore improving blood flow through the previously blocked artery. The problem is that the balloon damages the wall temporarily, creating a stimulus to the inner lining or endothelium to proliferate and restenosis the artery with fibrous tissue.
Stenting: Frequently the following angioplasty, a metal tube called a stent is placed in the artery to keep the lumen open after a successful dilatation. The stent acts as a scaffold, supporting the arterial walls, preventing collapse or recoil, and seals over injured areas of the endothelium. Some stents are coated with special drugs that help prevent the proliferation of the endothelium, and re-blockage of the affected artery. After stenting, the patient is asked to take drugs to prevent clotting of the metal surface.
If lifestyle changes and medications are not helpful in alleviating symptoms of atherosclerosis, and/or angioplasty with stenting has already been performed and is not technically feasible again, surgical bypass procedures may be indicated.
Bypass surgery: This surgery uses arteries or veins from other areas in the body to bypass the blocked arteries and improve blood flow to the downstream artery. When the surgery is performed on the coronary arteries, it is called coronary artery bypass surgery. Carotid artery endarterectomy Rotorooters the plaque on the inside of the artery so more easy flow of blood to the brain is accomplished. Bypass surgery of the leg arteries frequently uses specially designed tubes (grafts) from cloth, Dacron, or plastic to perform the bypass.
Can You Prevent Atherosclerosis?
To help prevent atherosclerosis, a person needs to reduce/eliminate the modifiable risk factors that one has (high blood pressure, high blood glucose levels, high blood cholesterol levels, cigarette smoking, obesity, lack of exercise).
One should eat a healthy diet low in saturated fat and rich in fruits and vegetables.
If emotional stress is a problem, one should find ways to reduce or control it.
Fortunately, taking steps to tackle some of the risk factors helps to modify other risk factors. For example, exercise helps a person to lose weight, which in turn helps to lower cholesterol levels and blood pressure.
What Is the Prognosis for Hardening of the Arteries?
The outcome of atherosclerosis is variable. At one end of the spectrum, many people with the critical limitation of blood flow to vital organs, like the heart and brain, survive for many years. At the other end of the spectrum, sudden cardiac death may be the first clinical manifestation of atherosclerosis. So, the emphasis must be placed on the individual to control his or her own identified risk factors and prevent atherosclerosis in the first place.