What Is It?
Coronary artery disease is the term commonly used to describe the buildup of fatty deposits and fibrous tissue (plaques) inside the arteries that supply blood to the heart (the coronary arteries). This buildup is called atherosclerosis. Coronary atherosclerosis eventually can cause the coronary arteries to become significantly narrower. This decreases the blood supply to parts of the heart muscle and triggers a type of chest pain called angina. Atherosclerosis also can cause a blood clot to form inside a narrowed coronary artery. This causes a heart attack, which can cause significant damage to the heart muscle.
The factors that increase the risk of developing coronary artery disease are basically the same as those for atherosclerosis:
Coronary artery disease is the most common chronic, life-threatening illness in the United States. It affects 11 million Americans. Earlier in life, men have a greater risk of coronary artery disease than do women. However, after menopause, a woman's risk eventually equals that of a man.
Symptoms
In most people, the most common symptom of coronary artery disease is the type of chest pain called angina, or angina pectoris. Angina usually is described as a squeezing, pressing or burning chest pain that tends to be felt mainly in the center of the chest or just below the center of the rib cage. It also can spread to the arms (especially the left arm), abdomen, neck, lower jaw or neck. Other symptoms can include sweating, nausea, dizziness or lightheadedness, breathlessness, or palpitations. Sometimes, when coronary artery disease causes burning chest pain and nausea, a patient may mistake heart symptoms for indigestion.
There are two types of chest pain related to coronary artery disease -- stable angina and acute coronary syndrome.
In stable angina, chest pain follows a predictable pattern. It usually occurs after extreme emotion, overexertion, a large meal, cigarette smoking, or exposure to extreme hot or cold temperatures. Symptoms usually last one to five minutes, and they disappear after a few minutes of rest. Stable angina is caused by a smooth plaque that partially obstructs blood flow in one or more coronary arteries.
Acute coronary syndrome (ACS) is much more dangerous. In most cases of ACS, fatty plaque inside an artery has developed a tear or break. The uneven surface can cause blood to clot on top of the disrupted plaque. This sudden blockage of blood flow results in unstable angina or a heart attack (myocardial infarction). In unstable angina, chest pain symptoms are more pronounced and less predictable compared to stable angina. Chest pains occur more frequently, often at rest, and last several minutes to hours. In addition, people with unstable angina frequently sweat profusely at times and develop aches in the jaw, shoulders and arms.
Many people with coronary artery disease, especially women, do not have any symptoms or have unusual symptoms. In these people, the only sign of coronary artery disease may be a suspicious change in the pattern of a test called an electrocardiogram (EKG), which records the heart's electrical activity. The test can be done at rest or during exercise (exercise stress test). The stress test is able to detect the problem in the coronary artery because exercise increases the heart muscle's demand for blood. The body can't meet this demand when the coronary arteries are significantly narrowed. In areas of the heart affected by narrowed coronary arteries, the heart muscle starves for blood and oxygen, and its electrical activity changes. This altered electrical activity is reflected in the patient's EKG results.
If the problem is not discovered, the first symptom of coronary artery narrowing may be a heart attack. A person who has a heart attack has a 15% chance of dying before receiving medical attention.
Diagnosis
Coronary artery disease usually is diagnosed after a person has chest pain or other symptoms such as shortness of breath with physical activity.
Your doctor will examine you, paying special attention to your chest and heart. During the physical examination, your doctor will press on your chest to see if it is tender. Tenderness in the area where you have chest pain could be a sign of a non-cardiac problem involving chest muscles, ribs or rib joints. Your doctor will use a stethoscope to listen for any abnormal heart sounds. The physical examination will be followed by one or more diagnostic tests to look for coronary artery disease. Possible tests include:
Expected Duration
Coronary artery disease is a long-term condition, and people can have different patterns of symptoms. Plaque in coronary arteries never will disappear completely. However, with diet, exercise and proper medication, the heart muscle adapts to decreased blood flow, and new, small blood channels can develop to increase the blood flow to the heart muscle.
Prevention
You can help to prevent coronary artery disease by controlling your risk factors for atherosclerosis. To do this:
Treatment
Coronary artery disease caused by atherosclerosis is treated with:
If your stable angina limits you physically because of chest pain, your doctor likely will advise you to have a coronary artery angiography (cardiac catheterization) to look for significant blockages. A heart specialist (cardiologist) also may do this test to diagnose coronary artery disease when other tests are not conclusive, in an emergency when a person is having a heart attack, and in some people with newly diagnosed congestive heart failure.
When one or more significant blockages are found, the heart specialist will determine if the blockage(s) can be opened with a procedure called balloon angioplasty, also called percutaneous transluminal coronary angioplasty or PTCA. In balloon angioplasty, a catheter is inserted into an artery in the groin or forearm and then is threaded through the circulatory system into the blocked coronary artery. Once inside the coronary artery, a small balloon at the catheter tip is inflated briefly to open the narrowed blood vessel. Usually, balloon inflation is followed by the placement of a stent, a wire mesh that expands with the balloon. The wire mesh remains inside the artery to keep it open. The balloon is deflated and the catheter is removed.
If the blockages cannot be opened with balloon angioplasty, the cardiologist will likely suggest coronary artery bypass surgery (CABG). CABG involves grafting one or more blood vessels onto the coronary arteries to bypass the narrowed or blocked areas. The blood vessels to be grafted can be taken from an artery inside the chest, an artery in the arm, and from a long vein in the leg.
The goal of treating heart attacks or sudden worsening of angina is to restore blood flow rapidly to the section of heart muscle no longer getting blood flow. Patients immediately receive medication to relieve pain. They also receive a beta-blocker to slow the heart rate and decrease the work of the heart and aspirin combined with other medications to dissolve or inhibit blood clotting. When possible, patients are transferred to a cardiac catheterization laboratory for immediate angiography and balloon angioplasty of the most significant blockage. In some people with coronary artery disease, other symptoms or complications will require treatment with additional therapies. For example, medication may be needed to treat cardiac arrhythmias (abnormal heart rhythms), low blood pressure or heart failure.
When To Call a Professional
Seek emergency help immediately if you have chest pain, even if you think that you are too young to be having heart problems. In patients whose chest pain signals heart attack, prompt treatment can limit heart muscle damage.
You should not waste precious time hoping that your chest pain disappears. About 15% of people having a heart attack die soon after chest symptoms begin and never reach the hospital alive.
Prognosis
In people with coronary artery disease, the outlook depends on many factors. People with stable angina who are taking medications regularly, eating properly and exercising as instructed by their doctors generally remain active. The prognosis for heart attacks when people reach the emergency room promptly has improved dramatically over the past 10 years. However, many people still die before reaching the hospital. This is why it is so important to prevent coronary artery disease.
Additional Info
American Heart Association (AHA)
7272 Greenville Ave.
Dallas, TX 75231
Toll-Free: 1-800-242-8721
http://www.americanheart.org/
National Heart, Lung, and Blood Institute (NHLBI)
P.O. Box 30105
Bethesda, MD 20824-0105
Phone: 301-592-8573
TTY: 240-629-3255
Fax: 301-592-8563
Email: nhlbiinfo@rover.nhlbi.nih.gov
http://www.nhlbi.nih.gov/
American College of Cardiology
Heart House
2400 N Street NW
Washington, DC 20037
Phone: 202-375-6000
Toll-Free: 1-800-253-4636
Email: resource@acc.org
http://www.acc.org/
