Coronary Artery Bypass Graft Surgery

Definition
Purpose
Demographics
Description
Diagnosis/Preparation
Aftercare
Risks
Normal results
Morbidity and mortality rates
Alternatives

Definition

Coronary artery bypass graft surgery (CABG) is a procedure in which one or more blocked coronary arteries are bypassed by a blood vessel graft to restore normal blood flow to the heart. These grafts usually come from the patient’s own arteries and veins located in the leg, arm, or chest.

Purpose

Coronary artery bypass graft surgery, also called coronary artery bypass surgery and bypass operation, is performed to restore blood flow to the heart. This relieves chest pain and ischemia, improves the patient’s quality of life, and, in some cases, prolongs the patient’s life. The goals of the procedure are to relieve symptoms of coronary artery disease, enable the patient to resume a normal lifestyle, and lower the risk of a heart attack or other heart problems.

According to the American Heart Association, appropriate candidates for coronary artery bypass graft surgery include patients who:

• have blockages in at least two or three major coronary arteries, especially if the blockages are in arteries that feed the heart’s left ventricle or are in the left anterior descending artery;
• have angina so severe that even mild exertion causes chest pain;
• have poor left ventricular function; and
• cannot tolerate percutaneous transluminal coronary angioplasty and do not respond well to drug therapy.

KEY TERMS

Angina— Also called angina pectoris, chest pain or discomfort that occurs when diseased blood vessels restrict blood flow to the heart.

Angiotensin-converting enzyme (ACE) inhibitor— Adrug that lowers blood pressure by interfering with the breakdown of a protein-like substance involved in blood pressure regulation.

Aorta— The main artery that carries blood from the heart to the rest of the body. The aorta is the largest artery in the body.

Artery— A vessel that carries oxygen-rich blood to the body.

Atherectomy— A non-surgical technique for treating diseased arteries with a rotating device that cuts or shaves away obstructing material inside the artery.

Atrium (plural Atria)— The right or left upper chamber of the heart.

Beta blocker— An anti-hypertensive drug that limits the activity of epinephrine, a hormone that increases blood pressure.

Brachytherapy— The use of radiation during angioplasty to prevent the artery from narrowing again (a process called restenosis).

Calcium channel blocker— A drug that lowers blood pressure by regulating calcium-related electrical activity in the heart.

Cardiac rehabilitation— A structured program of education and activity offered by hospitals and other organizations.

Coronary artery disease— Also called atherosclerosis, it is a build-up of fatty matter and debris in the coronary artery wall that causes narrowing of the artery.

Echocardiogram— An imaging procedure used to create a picture of the heart’s movement, valves, and chambers.

Graft— To implant living tissue surgically.

Homocysteine— An amino acid normally found in small amounts in the blood.

Ischemia— Decreased blood flow to an organ, usually caused by constriction or obstruction of an artery.

Lipoproteins— Substances that carry fat through the blood vessels for use or storage in other parts of the body.

Mammary artery— A chest wall artery that descends from the aorta and is commonly used for bypass grafts.

Radial artery— An artery located in the arm and used for bypass grafts.

Rotoblation— A non-surgical technique for treating diseased arteries.

Saphenous vein— A long vein in the thigh or calf commonly used for bypass grafts.

Stent— A device made of expandable, metal mesh that is placed (by using a balloon catheter) at the site of a narrowing artery; the stent stays in place to keep the artery open.

Sternum— Also called the breastbone, the sternum is the bone in the chest that is separated during open heart surgery.

Stress test— A test used to determine how the heart responds to stress.

Vein— A blood vessel that returns oxygen-depleted blood from various parts of the body to the heart.

Ventricle— A lower pumping chambers of the heart. There are two ventricles, right and left. The right ventricle pumps oxygen-poor blood to the lungs to be re-oxygenated. The left ventricle pumps oxygen-rich blood to the body.

Demographics

The American Heart Association estimated that in the United States in 2005, 469,000 coronary artery bypass procedures were performed on 261,000 individual patients. More than twice as many of these surgeries were performed on men than women. Fifteen thousand of these procedures were performed on people 15-44, 188,000 on people between ages 45 and 64, and the remainder on people age 65 and older.

Description

Coronary artery bypass graft surgery builds a detour around one or more blocked coronary arteries with a graft from a healthy vein or artery. The graft goes around the clogged artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart.

Procedure

After general anesthesia is administered, the surgeon removes the veins or prepares the arteries for grafting. The surgeon decides which grafts to use based on the location of the blockage, the amount of blockage, and the size of the patient’s coronary arteries. If the saphenous vein is to be used for the graft, a series of incisions are made in the patient’s thigh or calf. If the radial artery is to be used for the graft, incisions are made in the patient’s forearm. More commonly, a segment of the internal mammary artery is used for the graft, and the incisions are made in the chest wall. The internal mammary arteries are often used because they have shown the best long-term results. The removal of veins or arteries for grafting does not deprive the area from which they are removed of adequate blood flow.

In traditional coronary artery bypass surgery, the surgeon makes an incision down the center of the patient’s chest, cuts through the breastbone, and retracts the rib cage open to expose the heart. The patient is connected to a heart-lung bypass machine, also called a cardiopulmonary bypass pump, that takes over for the heart and lungs during the surgery. During this “on-pump” procedure, the heart-lung machine removes carbon dioxide from the blood and replaces it with oxygen. A tube is inserted into the aorta to carry the oxygenated blood from the bypass machine to the aorta for circulation to the body. The heart-lung machine allows heart contractions to be stopped, so the surgeon can operate on a still heart. Aortic clamps are used to restrict blood flow to the area of the heart where grafts will be placed so the heart is blood-free during the surgery. The clamps remain until the grafts are in place.

Some patients may be candidates for minimally invasive coronary artery bypass surgery or for off-pump bypass surgery. During minimally invasive surgery, smaller chest and graft removal incisions are used, promoting a quicker recovery and less risk of infection. Off-pump bypass surgery, also called beating heart surgery, is a surgical technique performed while the heart is still contracting (beating). The surgeon uses advanced equipment to stabilize portions of the heart and bypass the blocked artery while the rest of the heart keeps pumping and circulating blood through the body.

After the grafts are prepared, a small opening is made in the diseased coronary artery just below the blockage. Blood will be redirected through this opening once the graft is sewn in place. If a leg or arm vein is used, one end is connected to the coronary artery and the other to the aorta. If a mammary artery is used, one end is connected to the coronary artery while the other is already attached to the aorta and remains in place. The procedure is repeated on as many coronary arteries as necessary. On average, three or four coronary arteries are bypassed during surgery. Blood flow is checked to assure the graft supplies adequate blood to the heart.

If the procedure was done “on-pump,” electric shocks start the heart pumping again after the grafts have been completed. The heart-lung machine is turned off and the blood slowly returns to normal body temperature. After implanting pacing wires and inserting a chest tube to drain fluid, the surgeon closes the chest cavity. Sometimes a temporary pacemaker is attached to the pacing wires to regulate the heart rhythm until the patient’s condition improves. After surgery, the patient is transferred to an intensive care unit (ICU) for close monitoring.

Diagnosis/Preparation

Diagnosis

The diagnosis of coronary artery disease is made after the patient’s medical history is carefully reviewed, a physical exam is performed, and the patient’s symptoms are evaluated. Tests used to diagnose coronary artery disease include:

• electrocardiogram;
• stress tests;
• cardiac catheterization;
• imaging tests such as a chest X-ray, echocardiography, or computed tomography (CT) scan; and
• blood tests to measure blood cholesterol, triglycerides, and other substances.

Preparation

The patient should quit smoking or using tobacco products before the surgery, and the patient needs to make the commitment to be a nonsmoker after the surgery. There are many smoking cessation programs available through hospital or community groups. A health care provider can provide more information about ways quit smoking.

Coronary artery bypass graft surgery should ideally be postponed for three months after a heart attack. Whenever possible, patients should be medically stable before the surgery. If the patient develops a cold, fever, or sore throat within a few days before the surgery, he or she should notify the surgeon’s office.

During a preoperative appointment, usually scheduled one to two weeks before surgery, the patient will receive information about what to expect during the surgery and the recovery period. The patient will usually meet the cardiologist, anesthesiologist, nurse clinicians, and surgeon during this appointment or just before the procedure.

The evening before the surgery, the patient showers with antiseptic soap provided by the surgeon’s office. After midnight, the patient should not eat or drink anything.

The patient is usually admitted to the hospital day the surgery is scheduled. The patient should bring a list of current medications, allergies, and appropriate medical records upon admission to the hospital.

Before the surgery, the patient is given a blood-thinning drug (usually heparin) that helps to prevent blood clots. A sedative is given the morning of surgery. The chest and the area from where the graft will be taken are shaved.

Coronary angiography will have been previously performed to show the surgeon where the arteries are blocked and where the grafts might best be positioned. Heart monitoring is initiated. The patient is given general anesthesia before the procedure.

The length of the procedure depends upon the number of arteries being bypassed, but it generally takes from three to five hours or sometimes longer.

Aftercare

Recovery in the hospital

The patient recovers in a surgical intensive care unit for one to two days after the surgery. The patient will be connected to chest and breathing tubes, a mechanical ventilator, a heart monitor, and other monitoring equipment. A urinary catheter will be in place to drain urine. The breathing tube and ventilator are usually removed about six hours after surgery, but the other tubes remain in place as long as the patient is in the intensive care unit.

Drugs are prescribed to control pain and infection and to prevent unwanted blood clotting. Daily doses of aspirin are started within 6-24 hours after the procedure.

The patient is closely monitored during the recovery period. Vital signs and other parameters such as heart sounds, oxygen, and carbon dioxide levels in arterial blood are checked frequently. The chest tube is checked to ensure that it is draining properly. The patient may be fed intravenously for the first day or two.

Chest physiotherapy is started after the ventilator and breathing tubes are removed. The therapy includes coughing, turning frequently, and taking deep breaths. Sometimes oxygen is delivered via a mask to help loosen and clear secretions from the lungs. Other exercises will be encouraged to improve the patient’s circulation and prevent complications due to prolonged bed rest.

If there are no complications, the patient begins to resume a normal routine on the second day, including eating regular food, sitting up, and walking around a bit. Before being discharged from the hospital, the patient usually spends a few days under observation in a non-surgical unit. During this time, counseling is usually provided on eating right and starting a light exercise program to keep the heart healthy. The average hospital stay after coronary artery bypass graft surgery is five to seven days.

Recovery at home

INCISION AND SKIN CARE. The incision should be kept clean and dry. When the skin is healed, the incision should be washed with soapy water. The scar should not be bumped, scratched, or otherwise disturbed. Ointments, lotions, and dressings should not be applied to the incision unless specific instructions have been given to do so.

DISCOMFORT. While the incision scar heals, which takes one to two months, it may be sore. Itching, tightness, or numbness along the incision are common. Muscle or incision discomfort may occur in the chest during activity.

Swelling or aching may occur in the legs if the saphenous vein was used for the graft. Special support stockings may be needed to decrease leg swelling after surgery. While sitting, the patient should not cross the legs and the feet should be elevated. Walking daily, even if the legs are swollen, will help improve circulation and reduce swelling.

LIFESTYLE CHANGES. The patient needs to make several lifestyle changes after surgery, including:

• quitting smoking. Smoking causes damage to the bypass grafts and other blood vessels, increases the patient’s blood pressure and heart rate, and decreases the amount of oxygen available in the blood.
• managing weight. Maintaining a healthy weight, by watching portion sizes and exercising, is important. Being overweight increases the work of the heart.
• participating in an exercise program. The exercise program is usually tailored for the patient, who will be encouraged to participate in a cardiac rehabilitation program supervised by exercise professionals.
• making dietary changes. Patients should eat a lot of fruits, vegetables, whole grains, and non-fat or low-fat dairy products, and reduce fat intake to less than 30% of all calories.
• taking medications as prescribed. Aspirin and other heart medications may be prescribed, and the patient may need to take these medications for life.
• following up with health care providers. The patient must schedule follow-up visits to determine how effective the surgery was, to confirm that progressive exercise is safe, and to monitor his or her recovery and control risk factors.

Risks

Coronary artery bypass graft surgery is major surgery and patients may experience any of the normal complications associated with major surgery and anesthesia, such as the risk of bleeding, pneumonia, or infection. Other possible complications include:

• graft closure or blockage;
• development of blockages in other arteries;
• damage to the aorta;
• long-term development of atherosclerotic disease of saphenous vein grafts;
• abnormal heart rhythms;
• high or low blood pressure;
• recurrence of angina;
• blood clots that can lead to a stroke or heart attack;
• kidney failure;
• depression or severe mood swings; and
• possible short-term memory loss, difficulty thinking clearly, and problems concentrating for long periods (these effects generally subside within six months after surgery).

There is a higher risk for complications in patients who:

• are heavy smokers;
• have a history of lung, kidney, or metabolic diseases;
• have diabetes;
• have had a recent heart attack; or
• have a history of angina, ventricular arrhythmias, congestive heart failure, cerebrovascular disease, or mitral regurgitation.

Normal results

Full recovery from coronary artery bypass graft surgery takes two to three months and is a gradual process. Upon release from the hospital, the patient will feel weak because of the extended bed rest in the hospital. Within a few weeks, the patient should begin to feel stronger.

Most patients are able to drive in three to eight weeks, after receiving approval from their physician. Sexual activity can generally be resumed in three to four weeks, depending on the patient’s rate of recovery.

It takes about six to eight weeks for the sternum to heal. During this time, the patient should not perform activities that cause pressure or weight on the breastbone or tension on the arms and chest. Pushing and pulling heavy objects (as in mowing the lawn) should be avoided and lifting objects more than 20 lbs (9 kg) is not permitted. The patient should not hold his or her arms above shoulder level for a long period, such as when doing household chores. The patient should try not to stand in one place for longer than 15 minutes. Stair climbing is permitted unless other instructions have been given. Within four to six weeks, people with sedentary office jobs can return to work. People with physical jobs, such as construction work or jobs requiring heavy lifting, must wait longer (up to 12 weeks) or may have to change careers.

About 90% of patients experience significant improvements after coronary artery bypass graft surgery. Patients experience full relief from chest pain and resume their normal activities in about 70% of the cases; the remaining 20% experience partial relief.

Coronary artery bypass surgery does not prevent coronary artery disease from recurring. For most people, the graft remains open for about 10–15 years. Therefore, lifestyle changes are strongly recommended and medications are prescribed to reduce the risk for the return of coronary artery disease. About 40% of patients have a new blockage within 10 years after surgery and require a second bypass, change in medication, or an interventional procedure.

Morbidity and mortality rates

The risk of death while in the hospital during and after coronary artery bypass graft surgery is 2-1%, although the rate varies among individual hospitals and surgeons. In 5-10% of coronary artery bypass graft surgeries, the bypass graft stops supplying blood to the bypassed artery within one year. Younger people who are healthy except for the heart disease achieve good results with bypass surgery. Patients who have poorer results from coronary artery bypass graft surgery include those over the age of 70, those who have poor left ventricular function, are undergoing a repeat surgery or other procedures concurrently, and those who continue smoking, do not treat high cholesterolor other coronary risk factors, or have another debilitating disease.

Over the long term, symptoms recur in only about 3-4% of patients per year. Five years after coronary artery bypass graft surgery, survival expectancy is

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

The surgery team for coronary artery bypass graft surgery includes the cardiovascular surgeon, assisting surgeons, a cardiovascular anesthesiologist, a perfusion technologist (who operates the heart-lung machine), and specially trained nurses. The surgery is performed in a hospital.

90%, at 10 years it is about 85%, at 15 years it is about 55%, and at 20 years it is about 40%.

Angina recurs in about 40% of patients after 10 years. In most cases, it is less severe than before the surgery and can be controlled with drug therapy. In patients who have had vein grafts, 40% of the grafts are severely obstructed 10 years after the procedure. Repeat coronary artery bypass graft surgery may be necessary, and is usually less successful than the first surgery.

Alternatives

All patients with coronary artery disease can help improve their condition by making lifestyle changes such as quitting smoking, losing weight if they are overweight, eating healthy foods, reducing blood cholesterol, exercising regularly, and controlling diabetes and high blood pressure.

All patients with coronary artery disease should be prescribed medications to treat their condition. Antiplatelet medications such as aspirin or clopidogrel (Plavix) are usually recommended. Other medications used to treat angina may include beta blockers, nitrates, and angiotensin-converting enzyme (ACE) inhibitors. Medications may also be prescribed to lower lipoprotein levels, since elevated lipoprotein levels have been associated with an increased risk of cardiovascular problems.

Treatment with vitamin E is not recommended because it does not lower the rate of cardiovascular events in people with coronary artery disease. Antioxidants such as vitamin C and beta-carotene show some signs of helping reduce coronary artery disease, but not enough rigorously documented information about their effects is available and they are not recommended for routine use. Treatment with folic acid and vitamins B6 and B12 lowers homocysteine levels (reducing the risk for cardiovascular problems), but more studies are needed to determine if lowered homocysteine

QUESTIONS TO ASK THE DOCTOR

• Why is this surgery being performed?
• Am I a candidate for minimally invasive coronary artery bypass surgery?
• Which technique will be used during the surgery, the “on-pump” or “off-pump” technique?
• Who will be performing the surgery? How many years of experience does this surgeon have? How many other coronary artery bypass graft surgeries has this surgeon performed?
• Should I take my medications the day of the surgery?
• How long will I have to stay in the hospital after the surgery?
• After I go home from the hospital, how long will it take me to recover from surgery?
• What should I do if I experience chest discomfort or other symptoms similar to those I felt before surgery?
• What types of symptoms should I report to my doctor?
• How should I care for my incision?
• What types of medications will I have to take after surgery?
• When will I be able to resume my normal activities?
• If I have had the surgery once, can I have it again to correct future blockages?
• Are there any medications, foods, or activities I should avoid to prevent my symptoms from recurring?
• What lifestyle changes (including diet, weight management, exercise, and activity changes) are recommended after the procedure to improve my heart health?
• How often do I need to see my doctor for follow-up visits after the surgery?

levels correlate with a reduced rate of cardiovascular problems in treated patients.

Less invasive, nonsurgical interventional procedures, such as balloon angioplasty, stent placement, rotoblation, atherectomy, or brachytherapy, can be performed to open a blocked artery. These procedures may be the appropriate treatment for some patients before coronary artery bypass graft surgery is considered.

Enhanced external counterpulsation (EECP) may be a treatment option for patients who are not candidates for interventional procedures or coronary artery bypass graft surgery. During EECP, a set of cuffs is wrapped around the patient’s calves, thighs, and buttocks. These cuffs gently but firmly compress the blood vessels in the lower limbs to increase blood flow to the heart. The inflation and deflation of the cuffs are electronically synchronized with the heartbeat and blood pressure using electrocardiography and blood pressure monitors. EECP may encourage blood vessels to open small channels to eventually bypass blocked vessels and improve blood flow to the heart. Not all patients are candidates for this procedure, and treatments, lasting one to two hours, must be repeated about five times a week for up to seven weeks.

Resources

BOOKS

Lichtenberg, Maggie. The Open Heart Companion: Preparation and Guidance for Open-Heart Surgery Recovery. Santa Fe, NM: Open Heart Publishing, 2006.

Sheridan, Brett C. So You’re Having Heart Bypass Surgery. Hoboken, NJ: John Wiley, 2003.

OTHER

“Coronary Artery Bypass Surgery.” Medline Plus. January 24, 2008 [cited January 29, 2008]. http://www.nlm.nih.gov/medlineplus/coronaryarterybypasssurgery.html.

MyHeartCentral.com. [cited March 16, 2008]. http://www.healthcentral.com/heart-disease/.

Your Total Health: Heart Health.http://yourtotalhealth.ivillage.com/heart-health.

ORGANIZATIONS

American College of Cardiology, Heart House 2400 N Street, NW, Washington, DC, 20037, (800) 253-4636, http://www.acc.org.

American Heart Association, 7272 Greenville Ave., Dallas, TX, 75231, (800) 242-8721, http://www.americanheart.org.

The Cleveland Clinic Heart & Vascular Institute, 9500 Euclid Avenue, F25, Cleveland, OH, 44195, (866) 289-6911, http://www.clevelandclinic.org/heartcenter.

National Heart, Lung, and Blood Institute, P.O. Box 30105, Bethesda, MD, 20824-0105, (301) 592-8573, http://www.nhlbi.nih.gov.

Texas Heart Institute, Heart Information Service, P.O. Box 20345, Houston, TX, 77225-0345, (800) 292-2221, http://www.texasheartinstitute.org/.

Lori De Milto

Angela M. Costello

Tish Davidson, A.M.

Coronary artery bypass graft surgery

Definition

Coronary artery bypass graft surgery is a surgical procedure in which one or more blocked coronary arteries are bypassed by a blood vessel graft to restore normal blood flow to the heart. These grafts usually come from the patient's own arteries and veins located in the leg, arm, or chest.

Purpose

Coronary artery bypass graft surgery (also called coronary artery bypass surgery [CABG] and bypass operation) is performed to restore blood flow to the heart. This relieves chest pain and ischemia, improves the patient's quality of life, and, in some cases, prolongs the patient's life. The goals of the procedure are to relieve symptoms of coronary artery disease, enable the patient to resume a normal lifestyle, and to lower the risk of a heart attack or other heart problems.

According to the American Heart Association, appropriate candidates for coronary artery bypass graft surgery include patients who:

• have blockages in at least two to three major coronary arteries, especially if the blockages are in arteries that feed the heart's left ventricle or in the left anterior descending artery
• have angina so severe that even mild exertion causes chest pain
• have poor left ventricular function
• cannot tolerate percutaneous transluminal coronary angioplasty and do not respond well to drug therapy

Demographics

Coronary artery bypass graft surgery is widely performed in the United States. It is estimated that more than 800,000 coronary artery bypass graft surgeries are performed worldwide every year. The American Heart Association reports that 519,000 coronary artery bypass graft surgeries were performed in the United States in 2000, of which 371,000 were performed on men and 148,000 on women.

Description

Coronary artery bypass graft surgery builds a detour around one or more blocked coronary arteries with a graft from a healthy vein or artery. The graft goes around the clogged artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart.

Procedure

After general anesthesia is administered, the surgeon removes the veins or prepares the arteries for grafting. If the saphenous vein is to be used for the graft, a series of incisions are made in the patient's thigh or calf. If the radial artery is to be used for the graft, incisions are made in the patient's forearm. It is important to note that the removal of veins or arteries for grafting does not deprive the area of adequate blood flow.

More commonly, a segment of the internal mammary artery is used for the graft, and the incisions are made in the chest wall. The internal mammary arteries are most commonly used because they have shown the best long-term results. Because they have their own oxygen-rich blood supply, the internal mammary arteries can usually be kept intact at their origin, then sewn to the coronary artery below the site of blockage.

The surgeon decides which grafts to use, depending on the location of the blockage, the amount of the blockage, and the size of the patient's coronary arteries.

In traditional coronary artery bypass surgery, the surgeon makes an incision down the center of the patient's chest, cuts through the breastbone, and retracts the rib cage open to expose the heart. The patient is connected to a heart-lung bypass machine, also called a cardiopulmonary bypass pump, that takes over for the heart and lungs during the surgery. During this "on-pump" procedure, the heart-lung machine removes carbon dioxide from the blood and replaces it with oxygen. A tube is inserted into the aorta to carry the oxygenated blood from the bypass machine to the aorta for circulation to the body. The heart-lung machine allows the heart's beating to be stopped, so the surgeon can operate on a still heart. Aortic clamps are used to restrict blood flow to the area of the heart where grafts will be placed so the heart is blood-free during the surgery. The clamps remain until the grafts are in place.

Some patients may be candidates for minimally invasive coronary artery bypass surgery or for off-pump bypass surgery. During minimally invasive surgery, smaller chest and graft removal incisions are used, promoting a quicker recovery and less risk of infection. Off-pump bypass surgery, also called beating heart surgery, is a surgical technique performed while the heart is still beating. The surgeon uses advanced equipment to stabilize portions of the heart and bypass the blocked artery while the rest of the heart keeps pumping and circulating blood through the body.

After the grafts are prepared, a small opening is made just below the blockage in the diseased coronary artery. Blood will be redirected through this opening once the graft is sewn in place. If a leg or arm vein is used, one end is connected to the coronary artery and the other to the aorta; if a mammary artery is used, one end is connected to the coronary artery while the other remains attached to the aorta. The procedure is repeated on as many coronary arteries as necessary. On average, three or four coronary arteries are bypassed during surgery. Blood flow is checked to assure the graft supplies adequate blood to the heart.

If the procedure was done "on-pump," electric shocks start the heart pumping again after the grafts have been completed. The heart-lung machine is turned off and the blood slowly returns to normal body temperature. After implanting pacing wires and inserting a chest tube to drain fluid, the surgeon closes the chest cavity. Sometimes a temporary pacemaker is attached to the pacing wires to regulate the heart rhythm until the patient's condition improves. After surgery, the patient is transferred to an intensive care unit for close monitoring.

Diagnosis/Preparation

Diagnosis

The diagnosis of coronary artery disease is made after the patient's medical history is carefully reviewed, a physical exam is performed, and the patient's symptoms are evaluated. Tests used to diagnose coronary artery disease include:

• electrocardiogram
• stress tests
• cardiac catheterization
• imaging tests such as a chest x ray , echocardiography , or computed tomography (CT)
• blood tests to measure blood cholesterol, triglycerides, and other substances

Preparation

The individual should quit smoking or using tobacco products before the surgery. The individual needs to make the commitment to be a nonsmoker after the surgery. There are several smoking cessation programs available in the community. The individual can ask a health care provider for more information about quitting smoking.

Coronary artery bypass graft surgery should ideally be postponed for three months after a heart attack. Patients should be medically stable before the surgery, if possible.

During a preoperative appointment, usually scheduled within one to two weeks before surgery, the patient will receive information about what to expect during the surgery and the recovery period. The patient will usually meet the cardiologist, anesthesiologist, nurse clinicians, and surgeon during this appointment or just before the procedure.

If the patient develops a cold, fever, or sore throat within a few days before the surgery, he or she should notify the surgeon's office.

The evening before the surgery, the patient showers with antiseptic soap provided by the surgeon's office. After midnight, the patient should not eat or drink anything.

The patient is usually admitted to the hospital the same day the surgery is scheduled. The patient should bring a list of current medications, allergies, and appropriate medical records upon admission to the hospital .

Before the surgery, the patient is given a blood-thinning drug—usually heparin—that helps to prevent blood clots. A sedative is given the morning of surgery. The chest and the area from where the graft will be taken are shaved.

Coronary angiography will have been previously performed to show the surgeon where the arteries are blocked and where the grafts might best be positioned. Heart monitoring is initiated. The patient is given general anesthesia before the procedure.

The length of the procedure depends upon the number of arteries being bypassed, but it generally takes from three to five hours—sometimes longer.

Aftercare

Recovery in the hospital

The patient recovers in a surgical intensive care unit for one to two days after the surgery. The patient will be connected to chest and breathing tubes, a mechanical ventilator, a heart monitor, and other monitoring equipment. A urinary catheter will be in place to drain urine. The breathing tube and ventilator are usually removed about six hours after surgery, but the other tubes usually remain in place as long as the patient is in the intensive care unit.

Drugs are prescribed to control pain and to prevent unwanted blood clotting. Daily doses of aspirin are started within six to 24 hours after the procedure.

The patient is closely monitored during the recovery period. Vital signs and other parameters such as heart sounds, oxygen, and carbon dioxide levels in arterial blood are checked frequently. The chest tube is checked to ensure that it is draining properly. The patient may be fed intravenously for the first day or two.

Chest physiotherapy is started after the ventilator and breathing tubes are removed. The therapy includes coughing, turning frequently, and taking deep breaths. Sometimes oxygen is delivered via a mask to help loosen and clear secretions from the lungs. Other exercises will be encouraged to improve the patient's circulation and prevent complications due to prolonged bed rest.

If there are no complications, the patient begins to resume a normal routine on the second day, including eating regular food, sitting up, and walking around a bit. Before being discharged from the hospital, the patient usually spends a few days under observation in a nonsurgical unit. During this time, counseling is usually provided on eating right and starting a light exercise program to keep the heart healthy.

The average hospital stay after coronary artery bypass graft surgery is five to seven days.

Recovery at home

incision and skin care. The incision should be kept clean and dry. When the skin is healed, the incision should be washed with soapy water. The scar should not be bumped, scratched, or otherwise disturbed. Ointments, lotions, and dressings should not be applied to the incision unless specific instructions have been given.

discomfort. While the incision scar heals, which takes one to two months, it may be sore. Itching, tightness, or numbness along the incision are common. Muscle or incision discomfort may occur in the chest during activity.

Swelling or aching may occur in the legs if the saphenous vein was used for the graft. Special support stockings may be needed to decrease leg swelling after surgery. While sitting, the patient should not cross the legs and the feet should be elevated. Walking daily, even if the legs are swollen, will help improve circulation and reduce swelling.

lifestyle changes. The patient needs to make several lifestyle changes after surgery, including:

• Quitting smoking. Smoking causes damage to the bypass grafts and other blood vessels, increases the patient's blood pressure and heart rate, and decreases the amount of oxygen available in the blood.
• Managing weight. Maintaining a healthy weight, by watching portion sizes and exercising, is important. Being overweight increases the work of the heart.
• Participating in an exercise program. The exercise program is usually tailored for the patient, who will be encouraged to participate in a cardiac rehabilitation program supervised by exercise professionals.
• Making dietary changes. Patients should eat a lot of fruits, vegetables, grains, and non-fat or low-fat dairy products, and reduce fats to less than 30% of all calories.
• Taking medications as prescribed. Aspirin and other heart medications may be prescribed, and the patient may need to take these medications for life.
• Following up with health care providers. The patient must schedule follow-up visits to determine how effective the surgery was, to confirm that progressive exercise is safe, and to monitor his or her recovery and control risk factors.

Risks

Coronary artery bypass graft surgery is major surgery and patients may experience any of the normal complications associated with major surgery and anesthesia, such as the risk of bleeding, pneumonia, or infection. Possible complications include:

• graft closure or blockage
• development of blockages in other arteries
• damage to the aorta
• long-term development of atherosclerotic disease of saphenous vein grafts
• abnormal heart rhythms
• high or low blood pressure
• recurrence of angina
• blood clots that can lead to a stroke or heart attack
• kidney failure
• depression or severe mood swings
• possible short-term memory loss, difficulty thinking clearly, and problems concentrating for long periods (These effects generally subside within six months after surgery.)

There is a higher risk for complications in patients who:

• are heavy smokers
• have a history of lung, kidney, or metabolic diseases
• have diabetes
• have had a recent heart attack
• have a history of angina, ventricular arrhythmias, congestive heart failure, cerebrovascular disease, or mitral regurgitation

Normal results

Full recovery from coronary artery bypass graft surgery takes two to three months and is a gradual process. Upon release from the hospital, the patient will feel weak because of the extended bed rest in the hospital. Within a few weeks, the patient should begin to feel stronger.

Most patients are able to drive in about three to eight weeks, after receiving approval from their physician. Sexual activity can generally be resumed in three to four weeks, depending on the patient's rate of recovery.

It takes about six to eight weeks for the sternum to heal. During this time, the patient should not perform activities that cause pressure or weight on the breastbone or tension on the arms and chest. Pushing and pulling heavy objects (as in mowing the lawn) should be avoided and lifting objects more than 20 lbs (9 kg) is not permitted. The patient should not hold his or her arms above shoulder level for a long period of time, such as when doing household chores. The patient should try not to stand in one place for longer than 15 minutes. Stair climbing is permitted unless other instructions have been given.

Within four to six weeks, people with sedentary office jobs can return to work; people with physical jobs such as construction work or jobs requiring heavy lifting must wait longer (up to 12 weeks) or may have to change careers.

About 90% of patients experience significant improvements after coronary artery bypass graft surgery. Patients experience full relief from chest pain and resume their normal activities in about 70% of the cases; the remaining 20% experience partial relief.

For most people, the graft remains open for about 10–15 years.

Coronary artery bypass surgery does not prevent coronary artery disease from recurring. Therefore, lifestyle changes are strongly recommended and medications are prescribed to reduce this risk. About 40% of patients have a new blockage within 10 years after surgery and require a second bypass, change in medication, or an interventional procedure.

Morbidity and mortality rates

The risk of death during coronary artery bypass graft surgery is 2–3%.

In 5–10% of coronary artery bypass graft surgeries, the bypass graft stops supplying blood to the bypassed artery within one year. Younger people who are healthy except for the heart disease achieve good results with bypass surgery. Patients who have poorer results from coronary artery bypass graft surgery include those over the age of 70, those who have poor left ventricular function, are undergoing a repeat surgery or other procedures concurrently, and those who continue smoking, do not treat high cholesterol or other coronary risk factors, or have another debilitating disease.

Over the long term, symptoms recur in only about 3–4% of patients per year. Five years after coronary artery bypass graft surgery, survival expectancy is 90%, at 10 years it is about 85%, at 15 years it is about 55%, and at 20 years it is about 40%.

Angina recurs in about 40% of patients after 10 years. In most cases, it is less severe than before the surgery and can be controlled with drug therapy. In patients who have had vein grafts, 40% of the grafts are severely obstructed 10 years after the procedure. Repeat coronary artery bypass graft surgery may be necessary, and is usually less successful than the first surgery.

Alternatives

All patients with coronary artery disease can help improve their condition by making lifestyle changes such as quitting smoking, losing weight if they are overweight, eating healthy foods, reducing blood cholesterol, exercising regularly, and controlling diabetes and high blood pressure.

All patients with coronary artery disease should be prescribed medications to treat their condition. Antiplatelet medications such as aspirin or clopidogrel (Plavix) are usually recommended. Other medications used to treat angina may include beta blockers, nitrates, and angiotensin-converting enzyme (ACE) inhibitors. Medications may also be prescribed to lower lipoprotein levels, since elevated lipoprotein levels have been associated with an increased risk of cardiovascular problems.

Treatment with vitamin E is not recommended because it does not lower the rate of cardiovascular events in people with coronary artery disease. Although antioxidants such as vitamin C, beta-carotene, and probucol show promising results, they are not recommended for routine use. Treatment with folic acid and vitamins B6 and B12 lowers homocysteine levels (reducing the risk for cardiovascular problems), but more studies are needed to determine if lowered homocysteine levels correlate with a reduced rate of cardiovascular problems in treated patients.

Less invasive, nonsurgical interventional procedures—such as balloon angioplasty, stent placement, rotoblation, atherectomy, or brachytherapy—can be performed to open a blocked artery. These procedures may be the appropriate treatment for some patients before coronary artery bypass graft surgery is considered.

Enhanced external counterpulsation (EECP) may be a treatment option for patients who are not candidates for interventional procedures or coronary artery bypass graft surgery. During EECP, a set of cuffs is wrapped around the patient's calves, thighs, and buttocks. These cuffs gently but firmly compress the blood vessels in the lower limbs to increase blood flow to the heart. The inflation and deflation of the cuffs are electronically synchronized with the heartbeat and blood pressure using electrocardiography and blood pressure monitors. EECP may encourage blood vessels to open small channels to eventually bypass blocked vessels and improve blood flow to the heart. Not all patients are candidates for this procedure, and treatments, lasting one to two hours, must be repeated about five times a week for up to seven weeks.

Resources

books

American Heart Association. "Considering Surgery or Other Interventions." In Guide to Heart Attack Treatment, Recovery, Prevention. New York: Time Books, 1996.

Barry, Frank. The Healthy Heart Formula: The Powerful, New, Commonsense Approach to Preventing and Reversing Heart Disease. New York: John Wiley & Sons, 1998.

DeBakey, Michael E., and Antonio M. Gotto Jr. "Surgical Treatment of Coronary Artery Disease." In The New Living Heart. Holbrook, MA: Adams Media Corporation, 1997.

McGoon, Michael D., and Bernard J. Gersh. Mayo Clinic Heart Book: The Ultimate Guide to Heart Health, Second Edition. New York: William Morrow and Co., Inc., 2000.

Texas Heart Institute. "Heart Surgery." In Texas Heart Institute Heart Owner's Handbook. New York: John Wiley & Sons, 1995.

Topol, Eric J. Cleveland Clinic Heart Book: The Definitive Guide for the Entire Family from the Nation's Leading Heart Center. New York: Hyperion, 2000.

Trout, Darrell, and Ellen Welch. Surviving with Heart: Taking Charge of Your Heart Care. Golden, CO: Fulcrum Publishing, 2002.

periodicals

Eagle, K. A., et al. "ACC/AHA Guidelines for Coronary Artery Bypass Graft Surgery: Executive Summary and Recommendations: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Revise the 1991 Guidelines for Coronary Artery Bypass Graft Surgery)." Circulation 100 (1999): 1464–1480.

Mullany, Charles J. "Coronary Artery Bypass Surgery." Circulation 107 (2003): e21–e22.

Sabik, Joseph. Off-Pump Bypass Surgery: Improving Outcomes for Coronary Artery Bypass Surgery. Cleveland Clinic Heart Center, The Cleveland Clinic Foundation. November 2001.

organizations

American College of Cardiology. Heart House. 9111 Old Georgetown Rd., Bethesda, MD 20814-1699. (800) 253-4636, ext. 694, or (301) 897-5400. <http://www.acc.org>.

American Heart Association. 7272 Greenville Ave., Dallas, TX 75231. (800) 242-8721 or (214) 373-6300. <http://www.americanheart.org>.

The Cleveland Clinic Heart Center, The Cleveland Clinic Foundation. 9500 Euclid Avenue, F25, Cleveland, Ohio, 44195. (800) 223-2273, ext. 46697, or (216) 444-6697. <http://www.clevelandclinic.org/heartcenter>.

National Heart, Lung, and Blood Institute. National Institutes of Health. Building 1. 1 Center Dr., Bethesda, MD 20892. E-mail: [email protected]. <http://www.nhlbi.nih.gov>.

Texas Heart Institute. Heart Information Service. P.O. Box 20345, Houston, TX 77225-0345. <http://www.tmc.edu/thi>.

other

The Heart: An Online Exploration. The Franklin Institute Science Museum. 222 North 20th Street, Philadelphia, PA, 19103. (215) 448-1200. <http://sln2.fi.edu/biosci/heart.html>.

HeartCenterOnline. <http://www.heartcenteronline.com>.

Heart Information Network. <http://www.heartinfo.org>. HeartSurgeon.com. <http://www.heartsurgeon.com>.

Lori De Milto Angela M. Costello

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

The surgery team for coronary artery bypass graft surgery includes the cardiovascular surgeon, assisting surgeons, a cardiovascular anesthesiologist, a perfusion technologist (who operates the heart-lung machine), and specially trained nurses. The surgery is performed in a hospital.

QUESTIONS TO ASK THE DOCTOR

• Why is this surgery being performed?
• Am I a candidate for minimally invasive coronary artery bypass surgery?
• Which technique will be used during the surgery, the "on-pump" or "off-pump" technique?
• Who will be performing the surgery? How many years of experience does this surgeon have? How many other coronary artery bypass graft surgeries has this surgeon performed?
• Should I take my medications the day of the surgery?
• How long will I have to stay in the hospital after the surgery?
• After I go home from the hospital, how long will it take me to recover from surgery?
• What should I do if I experience chest discomfort or other symptoms similar to those I felt before surgery?
• What types of symptoms should I report to my doctor?
• How should I care for my incision?
• What types of medications will I have to take after surgery?
• When will I be able to resume my normal activities?
• If I have had the surgery once, can I have it again to correct future blockages?
• Are there any medications, foods, or activities I should avoid to prevent my symptoms from recurring?
• What lifestyle changes (including diet, weight management , exercise, and activity changes) are recommended after the procedure to improve my heart health?
• How often do I need to see my doctor for follow-up visits after the surgery?

Coronary Artery Bypass Graft Surgery

Definition

Coronary artery bypass graft surgery is a surgical procedure in which one or more blocked coronary arteries are bypassed by a blood vessel graft to restore normal blood flow to the heart. These grafts usually come from the patient's own arteries and veins located in the leg, arm, or chest.

Purpose

Coronary artery bypass graft surgery (also called coronary artery bypass surgery, CABG, and bypass operation) is performed to restore blood flow to the heart. This relieves chest pain and ischemia, improves the patient's quality of life, and in some cases, prolongs the patient's life. The goals of the procedure are to enable the patient to resume a normal lifestyle and to lower the risk of a heart attack.

The decision to perform coronary artery bypass graft surgery is a complex one, and there is some disagreement among experts as to when it is indicated. Many experts feel that it has been performed too frequently in the United States. According to the American Heart Association, appropriate candidates for coronary artery bypass graft surgery include patients with blockages in at least three major coronary arteries, especially if the blockages are in arteries that feed the heart's left ventricle; patients with angina so severe that even mild exertion causes chest pain; and patients who cannot tolerate percutaneous transluminal coronary angioplasty and do not respond well to drug therapy. Coronary artery bypass graft surgery often is the treatment of choice for patients with severe coronary artery disease (three or more diseased arteries with impaired function in the left ventricle).

Precautions

Coronary artery bypass graft surgery ideally should be postponed for three months after a heart attack. Patients should be medically stable before the surgery, if possible.

Description

Coronary artery bypass graft surgery builds a detour around one or more blocked coronary arteries with a graft from a healthy vein or artery. The graft goes around the clogged artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart. In the fall of 2003, a cardiac surgeon in Brazil reported success using a synthetic coronary artery bypass graft called the CardioPass on both an adult and pediatric patient. The company that makes the graft, CardioTech, was one of only two companies at the time in clinical trials on humans with synthetic grafts. This could be important, as some patients do not have a healthy graft to use in bypass surgery.

Coronary artery bypass graft surgery is major surgery performed in a hospital. The length of the procedure depends upon the number of arteries being bypassed, but it generally takes from four to six hours—sometimes longer. The average hospital stay is four to seven days. Full recovery from coronary artery bypass graft surgery takes three to four months. Within four to six weeks, people with sedentary office jobs can return to work; people with physical jobs must wait longer and sometimes change careers.

Coronary artery bypass graft surgery is widely performed in the United States. About 516,000 of these procedures were performed in 2001. The number performed has declined somewhat in the past five to 10 years due increased use of less invasive coronary angioplasty and stent therapy procedures.

Procedure

The surgery team for coronary artery bypass graft surgery includes the cardiovascular surgeon, assisting surgeons, a cardiovascular anesthesiologist, a perfusion technologist (who operates the heart-lung machine), and specially trained nurses. After general anesthesia is administered, the surgeon removes the veins or prepares the arteries for grafting. If the saphenous vein is to be used, a series of incisions are made in the patient's thigh or calf. More commonly, a segment of the internal mammary artery will be used and the incisions are made in the chest wall. The surgeon then makes an incision from the patient's neck to navel, saws through the breastbone, and retracts the rib cage open to expose the heart. The patient is connected to a heart-lung machine, also called a cardiopulmonary bypass pump, that cools the body to reduce the need for oxygen and takes over for the heart and lungs during the procedure. The heart is then stopped and a cold solution of potassium-enriched normal saline is injected into the aortic root and the coronary arteries to lower the temperature of the heart, which prevents damage to the tissue.

Next, a small opening is made just below the blockage in the diseased coronary artery. Blood will be redirected through this opening once the graft is sewn in place. If a leg vein is used, one end is connected to the coronary artery and the other to the aorta. If a mammary artery is used, one end is connected to the coronary artery while the other remains attached to the aorta. The procedure is repeated on as many coronary arteries as necessary. Most patients who have coronary artery bypass graft surgery have at least three grafts done during the procedure.

Electric shocks start the heart pumping again after the grafts have been completed. The heart-lung machine is turned off and the blood slowly returns to normal body temperature. After implanting pacing electrodes (if needed) and inserting a chest tube, the surgeon closes the chest cavity.

Success rate of coronary artery bypass graft surgery

About 90% of patients experience significant improvements after coronary artery bypass graft surgery. Patients experience full relief from chest pain and resume their normal activities in about 70% of cases; the remaining 20% experience partial relief. In 5-10% of coronary artery bypass graft surgeries, the bypass graft stops supplying blood to the bypassed artery within one year. Younger people who are healthy except for the heart disease do well with bypass surgery. Patients who have poorer results from coronary artery bypass graft surgery include those over the age of 70, those who have poor left ventricular function, or are undergoing a repeat surgery or other procedures concurrently, and those who continue smoking, do not treat high cholesterol or other coronary risk factors, or have another debilitating disease.

Long term, symptoms recur in only about 3-4% of patients per year. Five years after coronary artery bypass graft surgery, survival expectancy is 90%, at 10 years it is about 80%, at 15 years it is about 55%, and at 20 years it is about 40%.

Angina recurs in about 40% of patients after about 10 years. In most cases, it is less severe than before the surgery and can be controlled by drug therapy. In patients who have had vein grafts, 40% of the grafts are severely obstructed 10 years after the procedure. Repeat coronary artery bypass graft surgery may be necessary, and is usually less successful than the first surgery.

Minimally invasive coronary artery bypass graft surgery

There are two new types of minimally invasive coronary artery bypass graft surgery: port-access coronary artery bypass (also called PACAB or PortCAB) and minimally invasive coronary artery bypass (also called MIDCAB). These procedures are minimally invasive because they do not require the neck-to-navel incision, sawing through the breastbone, or opening the rib cage to expose the heart. Both procedures enable surgeons to work on the coronary arteries through small chest holes called ports and other small incisions. Port-access coronary artery bypass requires the use of a heart-lung machine but minimally invasive coronary artery bypass does not. Advantages of these procedures over standard coronary artery bypass graft surgery include a shorter hospital stay, a shorter recovery period, and lower costs.

Port-access coronary artery bypass enables surgeons to perform bypasses through smaller incisions. Using a video monitor to view the procedure, the surgeon passes instruments through ports in the patient's chest to perform the bypass. Mammary arteries or leg veins are used for the grafts. Minimally invasive coronary artery bypass is performed on a beating heart and is appropriate only for bypasses of one or two arteries. Small ports are made in the patient's chest, along with a small incision directly over the coronary artery to be bypassed. Generally, the surgeon uses a mammary artery for the bypass.

Early data on outcomes for port-access coronary artery bypass and minimally invasive coronary artery bypass are favorable. Mortality rates with port-access coronary artery bypass and minimally invasive coronary artery bypass are both less than 3%—about the same as in standard coronary artery bypass graft surgery. One clinical trial indicated that survival at seven years was the same in minimally invasive coronary artery bypass and standard coronary artery bypass graft surgery, but that another intervention was necessary five times more often with minimally invasive coronary artery bypass than with standard coronary artery bypass graft surgery. The American Heart Association Council on Cardio-Thoracic and Vascular Surgery feels that both procedures appear promising but that further study is needed. More data covering longer term outcomes are necessary in order to fully assess these procedures.

Preparation

The patient is usually admitted to the hospital the day before the coronary artery bypass graft surgery is scheduled. Coronary angiography has been previously performed to show the surgeon where the arteries are blocked and where the grafts might best be positioned. The patient is given a blood-thinning drug—usually heparin—that helps to prevent blood clots. The evening before the surgery, the patient showers with antiseptic soap and is shaved from chin to toes. After midnight, food and fluids are restricted. A sedative is prescribed on the morning of surgery and sometimes the night before. Heart monitoring begins.

Aftercare

The patient recovers in a surgical intensive care unit for at least the first two days after the surgery. He or she is connected to chest and breathing tubes, a mechanical ventilator, a heart monitor and other monitoring equipment, and a urinary catheter. The breathing tube and ventilator usually are removed within six hours of surgery, but the other tubes remain in place as long as the patient is in the intensive care unit. Drugs are prescribed to control pain and to prevent unwanted blood clotting. The patient is closely monitored. Vital signs and other parameters, such as heart sounds and oxygen and carbon dioxide levels in arterial blood, are checked frequently. The chest tube is checked to ensure that it is draining properly. The patient is fed intravenously for the first day or two. Daily doses of aspirin are started within six to 24 hours after the procedure. Chest physiotherapy is started after the ventilator and breathing tube are removed. The therapy includes coughing, turning frequently, and taking deep breaths. Other exercises will be encouraged to improve the patient's circulation and prevent complications due to prolonged bed rest.

If there are no complications, the patient begins to resume a normal routine around the second day. This includes eating regular food, sitting up, and walking around a little bit. Before being released from the hospital, the patient usually spends a few days under observation in a non-surgical unit. During this time, counseling is usually provided on eating right and starting a light exercise program to keep the heart healthy. Patients should eat a lot of fruits, vegetables, grains, and non-fat or low-fat dairy products, and reduce fats to less than 30% of all calories. An exercise program usually will be tailored for the patient, who will be encouraged to participate in a cardiac rehabilitation program where exercise will be supervised by professionals. Cardiac rehabilitation programs, offered by hospitals and other organizations, also may include classes on heart-healthy living.

Full recovery from coronary artery bypass graft surgery takes three to four months and is a gradual process. Upon release from the hospital, the patient will feel weak because of the extended bed rest in the hospital. Within a few weeks, the patient should begin to feel stronger.

While the incision scar from coronary artery bypass graft surgery heals, which takes one to two months, it may be sore. The scar should not be bumped, scratched, or otherwise disturbed. An exercise test often is conducted after the patient leaves the hospital to determine how effective the surgery was and to confirm that progressive exercise is safe.

Risks

Coronary artery bypass graft surgery is major surgery and patients may experience any of the complications associated with major surgery. The risk of death during coronary artery bypass graft surgery is two to three percent. Possible complications include graft closure and development of blockages in other arteries, long-term development of atherosclerotic disease of saphenous vein grafts, abnormal heart rhythms, high or low blood pressure, blood clots that can lead to a stroke or heart attack, infections, and depression. There is a higher risk for complications in patients who are heavy smokers, patients who have serious lung, kidney, or metabolic problems, or patients who have a reduced supply of blood to the brain. A 2003 report also described poverty as a risk factor for complications and death following coronary artery bypass surgery. It is likely that being poor is associated with a greater degree of stress, social isolation, and inadequate access to quick or preventive treatment.

Resources

PERIODICALS

"CardioPass Synthetic Coronary Artery Bypass Graft Implanted in Baby." Medical Devices & Surgical Technology Week September 7, 2003: 79.

"Graft Functioning Well in Coronary Artery Bypass Patient." Cardiovascular Week September 15, 2003: 38.

"Poverty Increases Risk of Complications and Death After CABG." Heart Disease Weekly September 7, 2003: 19.

Simonsen, Michael. "Changing Role for Cardiac Surgery as Use of Stents Continues Growth." Cardiovascular Device Update March 2003: 1-7.

Smith, Laquita Bowen. "Not-So-Open Heart Surgery: New Equipment Allows for a Three-Inch Incision." Memphis Business Journal 18, no. 53 (May 12 1997): 49.

ORGANIZATIONS

American Heart Association. 7320 Greenville Ave, Dallas, TX 75231. (214) 373-6300. 〈http://www.americanheart.org〉.

Texas Heart Institute. Heart Information Service. P.O. Box 20345, Houston, TX 77225-0345. 〈http://www.tmc.edu/thi〉.

KEY TERMS

Aorta— The main artery that carries blood from the heart to the rest of the body The aorta is the largest artery in the body.

Graft— To implant living tissue surgically. In coronary artery bypass graft surgery, healthy veins or arteries are grafted to coronary arteries.

Mammary artery— A chest wall artery that descends from the aorta and is commonly used for bypass grafts.

Saphenous vein— A long vein in the thigh or calf commonly used for bypass grafts.

Ventricles— The left and right ventricles are the large chambers of the heart. The ventricles propel blood to the lungs and the rest of the body.