Coronary heart disease (CHD) is a narrowing of the small blood vessels that supply blood and oxygen to the heart. CHD is also called coronary artery disease.

Coronary heart disease is usually caused by a condition called atherosclerosis, which occurs when fatty material and a substance called plaque builds up on the walls of your arteries. This causes them to get narrow. As the coronary arteries narrow, blood flow to the heart can slow down or stop, causing chest pain (stable angina), shortness of breath, heart attack, and other symptoms.

Coronary heart disease (CHD) is the leading cause of death in the United States for men and women. According to the American Heart Association, more than 15 million people have some form of the condition.

Men in their 40s have a higher risk of CHD than women. But, as women get older, their risk increases so that it is almost equal to a man's risk. See: Heart disease and women

Many things increase your risk for CHD. Bad genes (heredity) can increase your risk. You're more likely to develop the condition if someone in your family has had it -- especially if they had it before age 50. Your risk for CHD goes up the older you get.

The following factors also increase your risk of CHD:

• Diabetes
• High blood pressure
• High LDL "bad" cholesterol
• Low HDL "good" cholesterol
• Menopause
• Not getting enough physical activity or exercise
• Obesity
• Smoking

Higher-than-normal levels of inflammation-related substances may also increase your risk for a heart attack. Such substances include C-reactive protein and fibrinogen. Increased levels of a chemical called homocysteine, an amino acid, are also linked to an increased risk of a heart attack.

Symptoms may be very noticeable, but sometimes you can have the disease and not have any symptoms.

Chest pain or discomfort (angina) is the most common symptom. You feel this pain when the heart is not getting enough blood or oxygen. How bad the pain is varies from person to person.

There are two main types of chest pain:

• Atypical chest pain -- often sharp and comes and goes. You can feel it in your left chest, abdomen, back, or arm. It is unrelated to exercise and not relieved by rest or a medicine called nitroglycerin. Atypical chest pain is more common in women.
• Typical chest pain -- feels heavy or like someone is squeezing you. You feel it under your breast bone (sternum). The pain usually occurs with activity or emotion, and goes away with rest or a medicine called nitroglycerin.

Adults with typical chest pain have a higher risk of CHD than those with atypical chest pain.

Other symptoms include:

• Shortness of breath
• Heart attack -- in some cases, the first sign of CHD is a heart attack

Many tests help diagnose CHD. Usually, your doctor will order more than one test before making a definite diagnosis.

Tests may include:

• Electrocardiogram (ECG)
• Exercise stress test
• Echocardiogram
• Nuclear scan
• Coronary angiography/arteriography
• Electron-beam computed tomography (EBCT) to look for calcium in the lining of the arteries -- the more calcium, the higher your chance for CHD
• Coronary CT angiography
• Magnetic resonance angiography

Treatment depends on your symptoms and how severe the disease is.

If you have coronary artery disease that does not cause symptoms, you can be treated with either medicine or angioplasty with stenting. Recent studies show that medicine and angioplasty with stenting have equal benefits. Angioplasty with stenting does not help you live longer, but it can reduce angina or other symptoms of CHD.

Angioplasty with stenting, however, can be a life-saving procedure if you are having a heart attack.

Medications used to treat CHD include:

• ACE inhibitors to lower blood pressure
• Blood thinners (antiplatelet drugs) to reduce your risk of blood clots
• Beta-blockers to lower heart rate, blood pressure, and oxygen use by the heart
• Calcium channel blockers to relax arteries, lowering blood pressure and reducing strain on the heart
• Diuretics to lower blood pressure
• Nitrates (such as nitroglycerin) to stop chest pain and improve blood supply to the heart
• Statins to lower cholesterol

Procedures to treat and diagnose CHD are called percutaneous coronary interventions, or PCIs. Angioplasty and stenting are types of PCIs. Other types include:

• Coronary atherectomy
• Coronary radiation implant or coronary brachytherapy

Coronary brachytherapy delivers radiation into the coronary arteries. This treatment is only for patients who have had a stent-related problems.

Surgeries used to treat CHD include:

• Coronary artery bypass surgery
• Minimally invasive heart surgery

Lifestyle changes are very important. Your doctor may tell you to:

• Avoid or reduce the amount of salt (sodium) you eat
• Eat a heart healthy diet -- one that is low in saturated fats, cholesterol, and trans fat
• Get regular exercise and maintain a healthy weight
• Keep your blood sugar strictly under control if you have diabetes
• Stop smoking

Everyone recovers differently. Some people can maintain a healthy life by changing their diet, stopping smoking, and taking medications exactly as the doctor prescribes. Others may need medical procedures such as angioplasty or surgery.

Although everyone is different, early detection of CHD generally results in a better outcome.

• Heart attack
• Heart failure
• Unstable angina
• Sudden death

If you have any of the risk factors for CHD, set up an appointment with your doctor to discuss prevention and possible treatment.

If you have angina, shortness of breath, or symptoms of a heart attack, immediately contact your health care provider, call the local emergency number (such as 911), or go to the emergency room.

See your health care provider regularly. Tips for preventing CHD or lowering your risk of the disease:

• Avoid or reduce stress as best as you can.
• Don't smoke.
• Eat well-balanced meals that are low in fat and cholesterol and include several daily servings of fruits and vegetables.
• Get regular exercise. If your weight is considered normal, get at least 30 minutes of exercise every day. If you are overweight or obese, experts say you should get 60 to 90 minutes of exercise every day.
• Keep your blood pressure, blood sugar, and cholesterol under control.

Moderate amounts of alcohol (1 glass a day for women, 2 for men) may reduce your risk of cardiovascular problems. However, drinking larger amounts does more harm than good.

If you have one or more risk factors for coronary heart disease, talk to your doctor about possibly taking an aspirin a day to help prevent a heart attack or stroke. Low-dose aspirin therapy may be prescribed if the benefit is likely to outweigh the risk of gastrointestinal side effects.

New guidelines no longer recommend hormone replacement therapy, vitamins E or C, antioxidants, or folic acid to prevent heart disease.

Mosca L, Banka CL, Benjamin EJ, et al. Evidence-Based Guidelines for Cardiovascular Disease Prevention in Women: 2007 Update. Circulation. 2007; Published online before print February 19, 2007.

Smith SC Jr, Allen J, Blair SN, et al. AHA/ACC guidelines for secondary prevention for patients with coronary and other atherosclerotic vascular disease: 2006 update: endorsed by the National Heart, Lung, and Blood Institute. Circulation. 2006 May 16;113(19):2363-72. Erratum in: Circulation. 2006 Jun 6;113(22):e847.

Boden WE, O'rourke RA, Teo KK, et al. Optimal Medical Therapy with or without PCI for Stable Coronary Disease. N Engl J Med. 2007 Mar 26; [Epub ahead of print].

American Heart Association. Heart Disease and Stroke Statistics — 2007 Update. Dallas, Texas: American Heart Association; 2007.