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Note: All links within content go to MayoClinic.com

Arteries are blood vessels that carry oxygen and nutrients from your heart to the rest of your body. Healthy arteries are flexible, strong and elastic. Over time, however, too much pressure in your arteries can make the walls thick and stiff — sometimes restricting blood flow to your organs and tissues. This process is called arteriosclerosis, or hardening of the arteries.

Atherosclerosis is a specific type of arteriosclerosis, but the terms are often used interchangeably.

Although atherosclerosis is often considered a heart problem, it can affect arteries anywhere in your body. For example:

• When arteries leading to your limbs are affected, you may develop circulation problems in your arms and legs called peripheral arterial disease.
• When arteries to your heart are affected, you may have coronary artery disease, chest pain (angina) or a heart attack.
• When arteries supplying blood to your brain are affected, you could have a transient ischemic attack (TIA) or stroke.
• Atherosclerosis can also lead to a bulge in the wall of your artery (aneurysm).

You may not know that you have atherosclerosis until a hardened artery causes a medical emergency. But you can take steps to protect yourself. Healthy lifestyle changes and medications can help.

Atherosclerosis develops gradually. There are usually no signs or symptoms until an artery is so narrowed or clogged that it can't supply adequate blood to your organs and tissues. Sometimes a blood clot completely obstructs blood flow.

The specific signs and symptoms depend on which arteries are affected. For example:

• Heart arteries. Obstruction of the arteries to your heart (coronary arteries) may cause symptoms of heart attack, such as chest pain.
• Arteries supplying the brain. Obstruction of the carotid arteries in your neck may cause symptoms of stroke, such as sudden numbness, weakness or dizziness.
• Arteries in the arms and legs. Obstruction of the arteries supplying blood to your arms and legs may cause symptoms of peripheral arterial disease, such as leg pain when walking (intermittent claudication).

Sometimes hardening of the arteries causes erectile dysfunction in men.

Atherosclerosis is a slow, progressive disease that may begin as early as childhood. Although the exact cause is unknown, researchers suspect that atherosclerosis starts with damage or injury to the inner layer of an artery. The damage may be caused by various factors, including:

• High blood pressure
• High cholesterol
• An irritant, such as nicotine
• Certain diseases, such as diabetes

Once the inner wall of an artery is damaged, blood cells called platelets often clump at the injury site to try to repair the artery. Over time, fatty deposits (plaques) made of cholesterol and other cellular waste products also accumulate and harden, narrowing the space in your arteries. Organs and tissues that are served by these narrowed vessels don't get an adequate supply of blood.

Eventually pieces of the fatty deposits may rupture and enter your bloodstream. This can cause a blood clot to form at the site and damage your organs, such as in a heart attack. A blood clot can also travel to other parts of your body and partially or totally block blood flow to another organ.

Hardening of the arteries occurs over time. In addition to simply getting older, factors that increase the risk of atherosclerosis include:

• High blood pressure
• High cholesterol
• Diabetes
• Obesity
• Smoking
• A family history of aneurysm or early heart disease

If you suspect that you have atherosclerosis — or risk factors for hardening of the arteries — talk to your doctor. Also pay attention to early symptoms of inadequate blood flow, such as chest pain, leg pain or numbness. Early diagnosis and treatment can stop progression of atherosclerosis and prevent a medical emergency.

Your doctor may find signs of narrowed, enlarged or hardened arteries during a physical exam. These include:

• A weak or absent pulse below the narrowed area of your artery
• Decreased blood pressure in an affected limb
• Whooshing sounds (bruits) over your arteries, heard with a stethoscope
• Signs of a pulsating bulge (aneurysm) in your abdomen or behind your knee
• Evidence of poor wound healing in the area where your blood flow is restricted

Depending on the results of the physical exam, your doctor may suggest one or more diagnostic tests, including:

• Blood tests. Lab tests can detect increased levels of cholesterol, blood sugar and other substances that may increase the risk of atherosclerosis.
• Doppler ultrasound. Your doctor may use a special ultrasound device (Doppler ultrasound) to measure your blood pressure at various points along your arm or leg. These measurements can help your doctor gauge the degree of any blockages, as well as the speed of blood flow in your arteries.
• Ankle-brachial index. Your doctor may compare the blood pressure in your ankle with the blood pressure in your arm. This is known as the ankle-brachial index. An abnormal difference may indicate peripheral vascular disease, which is usually caused by atherosclerosis.
• Electrocardiogram (ECG). An electrocardiogram records electrical signals as they travel through your heart. An ECG can often reveal evidence of a previous heart attack or one that's in progress. If your signs and symptoms occur most often during exercise, your doctor may ask you to walk on a treadmill or ride a stationary bike during an ECG.
• Angiogram. To better view blood flow through your heart, your doctor may inject a special dye into your arteries before a chest X-ray. This is known as an angiogram. The dye outlines narrow spots and blockages on the X-ray images.
• Other imaging tests. Your doctor may use ultrasound, a computerized tomography (CT) scan or a magnetic resonance angiogram (MRA) to study your arteries. These tests can often show hardening and narrowing of large arteries, as well as aneurysms and calcium deposits in the artery walls.

A new imaging test that measures endothelial function — how well your blood vessels can increase blood flow when needed — may one day become another way to detect early atherosclerosis.

When your arteries narrow, tissues supplied by an affected artery don't receive enough blood when demand is greatest — particularly during physical activity. This can result in injury to your organs, including heart attack or stroke.

Aneurysms are another serious complication of atherosclerosis. Pain and throbbing in the area of an aneurysm is a common symptom. If an aneurysm bursts, you may face life-threatening internal bleeding. Although this is usually a sudden, catastrophic event, a slow leak is possible. If a blood clot within an aneurysm dislodges, it may obstruct an artery at some distant point.

Poor arterial circulation can also blunt sensation to heat or cold in your extremities, making you more susceptible to damage from both burns and freezing. Rarely, poor circulation to your extremities can cause tissue death (gangrene).

Lifestyle changes can promote healthier arteries. If you smoke, quit. Eat healthy foods, and get regular physical activity. Sometimes medication or surgical procedures may be recommended as well.

Medication
Various drugs can slow — or sometimes even reverse — the effects of atherosclerosis. Here are some common choices:

• Cholesterol medications. Aggressively lowering your low-density lipoprotein (LDL) cholesterol, the "bad" cholesterol, can slow, stop or even reverse the buildup of fatty deposits in your arteries. Boosting your high-density lipoprotein (HDL) cholesterol, the "good" cholesterol, may help, too. Your doctor can choose from a range of cholesterol medications, including drugs known as statins and fibrates.
• Anti-platelet medications. Your doctor may prescribe anti-platelet medications, such as aspirin, to reduce the likelihood that platelets will clump in narrowed arteries, form a blood clot and cause further blockage.
• Anticoagulants. An anticoagulant, such as heparin or warfarin (Coumadin), can help thin your blood to prevent clots from forming.
• Blood pressure medications.Medications to control blood pressure — such as beta blockers, angiotensin-converting enzyme (ACE) inhibitors and calcium channel blockers — can help slow the progression of atherosclerosis.
• Other medications. Your doctor may suggest certain medications to control specific risk factors for atherosclerosis, such as diabetes. Sometimes medications to treat symptoms of atherosclerosis, such as leg pain during exercise, are prescribed.

Surgery and other procedures
Sometimes more aggressive treatment is needed. If you have severe symptoms, hampered organ function, or a blockage that threatens muscle or skin tissue survival, you may be a candidate for one of the following procedures:

• Angioplasty. In this procedure, your doctor inserts a long, thin tube (catheter) into the blocked or narrowed part of your artery. A wire with a deflated balloon is passed through the catheter to the narrowed area. The balloon is then inflated, compressing the deposits against your artery walls. A mesh tube (stent) may be left in the artery to help keep the artery open. Angioplasty may also be done with laser technology.
• Endarterectomy. In some cases, fatty deposits must be surgically removed from the walls of a narrowed artery. When the procedure is done on arteries in the neck (the carotid arteries), it's known as carotid endarterectomy.
• Thrombolytic therapy. If you have an artery that's blocked by a blood clot, your doctor may insert a clot-dissolving drug into your artery at the point of the clot to break it up.
• Bypass surgery. Your doctor may create a graft bypass using a vessel from another part of your body or a tube made of synthetic fabric. This allows blood to flow around the blocked or narrowed artery.

Gene therapy
Researchers have identified many genes involved in the development and progression of atherosclerosis. Targeted gene therapy may one day provide new treatments for atherosclerosis.

Lifestyle changes can help you prevent or slow the progression of atherosclerosis.

• Stop smoking. Smoking damages your arteries. If you smoke, quitting is the best way to halt the progression of atherosclerosis and reduce your risk of complications.
• Get moving. Regular exercise can condition your muscles to use oxygen more efficiently. Physical activity can also improve circulation and promote development of new blood vessels that form a natural bypass around obstructions (collateral vessels).
• Eat healthy foods. A heart-healthy diet based on fruits, vegetables and whole grains — and low in saturated fat, cholesterol and sodium — can help you control your weight, blood pressure and cholesterol.
• Manage stress. Reduce stress as much as possible. Practice healthy techniques for managing stress, such as muscle relaxation and deep breathing.

If you have high cholesterol, high blood pressure, diabetes or another chronic disease, work with your doctor to manage the condition and promote overall health.