A coronary artery bypass surgery is performed on one or more of the coronary arteries, which lie on the outer surface of the heart and supply the heart muscle with the oxygen and nutrients it needs. The purpose of the operation is to bypass the obstructed portion of the artery and allow blood to flow freely to the heart muscle.
To bypass the blocked area, the surgeon uses a blood vessel taken from another part of the body, such as the internal mammary artery (located behind the sternum), the radial artery (in the wrist), or saphenous veins (usually taken from the legs).
For use in coronary bypass surgery, arteries are preferred to saphenous veins because they are not as susceptible to atherosclerosis. Moreover, the use of veins requires extremely strict attention to diet, LDL cholesterol, and blood pressure in order to prevent narrowing and eventual closure; quitting smoking is essential.
The decision to undergo coronary bypass surgery instead of an angioplasty should take into account many factors. It's important to determine which arteries are narrowed and to what degree. Coronary bypass surgery is often recommended to people who have a narrowed left main coronary artery or a significantly narrowed left anterior descending (LAD) artery.
The risk of death is greatly increased when these particular arteries are narrowed because they feed other critical arteries. Other people who generally tend to fare better with coronary bypass surgery rather than an angioplasty include those who have serious narrowing in three major coronary blood vessels; multiple narrowing in any blood vessels and reduced ability to pump blood from the left ventricle of the heart; and significant narrowing in two blood vessels and partial narrowing of the LAD.
Other factors to consider before undergoing coronary bypass surgery include advanced age, the individual's anatomy of the heart and surrounding blood vessels, and -- when possible -- the person's preference.
Current evidence suggests that coronary artery bypass surgery is effective for diabetics when complete revascularization (bypassing all the arteries that are significantly narrowed) can be accomplished. However, diabetics experience a higher rate of complications and death due to surgery. Because of this, diabetics should closely monitor and intensively manage their risk factors to reduce the likelihood of revascularization of any kind.
People who have had coronary artery bypass surgery and are recovering should begin an intensive prevention program before going home. Mainstays of the prevention program include drugs such as aspirin, beta blockers, statins, and ACE inhibitors. Patients should also receive counseling on diet and lifestyle changes, such as quitting smoking and exercising regularly.
Cardiac rehabilitation programs can be especially helpful not only for beginning an exercise program but also for help implementing all aspects of the coronary prevention program.
Evaluation for depression is important since it can seriously impair the likelihood that a person will follow the necessary diet and drug regimen. Evidence suggests that selective serotonin reuptake inhibitor (SSRI) antidepressants, such as sertraline and citalopram, can effectively and safely treat depression in people who have had a heart attack. There is no definitive evidence, however, that such treatment reduces future coronary events.
There's also no hard evidence in favor of chelation therapy, the removal of calcium from blood-vessel walls. Find out why people believe in it, and the concerns about this process, on the next page.