Coronary Artery Bypass Graft Surgery (CABG)

What is coronary bypass graft surgery?

Coronary artery bypass graft surgery (CABG) is a procedure used to treat coronary artery disease. Coronary artery disease (CAD) is the narrowing of the coronary arteries - the blood vessels that supply oxygen and nutrients to the heart muscle. CAD is caused by a build-up of fatty material within the walls of the arteries. This build-up narrows the inside of the arteries, limiting the supply of oxygen-rich blood to the heart muscle.

One way to treat the blocked or narrowed arteries is to bypass the blocked portion of the coronary artery with a piece of a healthy blood vessel from elsewhere in the body. Blood vessels, or grafts, used for the bypass procedure may be pieces of a vein from the legs or an artery in the chest. An artery from the wrist may also be used. One end of the graft is attached above the blockage and the other end is attached below the blockage. Blood is routed around, or bypasses, the blockage by going through the new graft to reach the heart muscle. This is called coronary artery bypass surgery.

Traditionally, to bypass the blocked coronary artery, a large incision is made in the chest and the heart is temporarily stopped so that the surgeon can perform the delicate procedure. To open the chest, the breastbone (sternum) is cut in half and spread apart. Once the heart is exposed, tubes are inserted into the heart so that the blood can be pumped through the body by a cardiopulmonary bypass machine (heart-lung machine). The bypass machine is necessary to pump blood while the heart is stopped and kept still in order for the surgeon to perform the bypass operation.

While the traditional "open heart" procedure is still commonly done and often preferred in many situations, less invasive techniques have been developed to bypass blocked coronary arteries. "Off-pump" procedures, in which the heart does not have to be stopped, were developed in the 1990's. Other minimally invasive procedures, such as keyhole surgery (performed through very small incisions) and robotic procedures (performed with the aid of a moving mechanical device), may be used.

Why might I need coronary artery bypass surgery?

Coronary artery bypass graft surgery (CABG) is used to treat a blockage or narrowing of one or more of the coronary arteries to restore the blood supply to the heart muscle.

Symptoms of coronary artery disease may include, but are not limited to:

  • Chest pain
  • Fatigue (severe tiredness)
  • Palpitations
  • Abnormal heart rhythms
  • Shortness of breath
  • Swelling in the hands and feet

Unfortunately, there may be no symptoms of early coronary artery disease, yet the disease will continue to progress until there's enough artery blockage to cause symptoms and problems. If the blood supply to the heart muscle continues to decrease as a result of increasing obstruction of a coronary artery, a heart attack may occur. If the blood flow can't be restored to the particular area of the heart muscle affected, the tissue dies.

There may be other reasons for your doctor to recommend CABG surgery.

What are the risks of coronary artery bypass surgery?

Possible risks associated with coronary artery bypass graft surgery (CABG) include, but are not limited to, the following:

  • Bleeding during or after the surgery
  • Blood clots that can cause heart attack, stroke, or lung problems
  • Infection at the incision site
  • Pneumonia
  • Breathing problems
  • Cardiac arrhythmias (abnormal heart rhythms)

There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.

How do I get ready for coronary artery bypass surgery?

  • Your doctor will explain the procedure and ask if you have any questions.
  • You will be asked to sign a consent form that gives your permission to do the test. Read the form carefully and ask questions if anything is not clear.
  • In addition to a complete medical history, your doctor may perform a complete physical exam to ensure you are in good health before undergoing the procedure. You may need blood tests or other diagnostic tests.
  • You will be asked to fast (not eat or drink) for 8 hours before the procedure, generally after midnight.
  • If you are pregnant or think you are pregnant, tell your doctor.
  • Tell your doctor if you are sensitive to or are allergic to any medications, iodine, latex, tape, or anesthetic agents (local and general).
  • Tell your doctor about all medications (prescription and over-the-counter), vitamins, herbs, and supplements that you are taking.
  • Tell your doctor if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. You may need to stop some of these medications prior to the procedure.
  • Your doctor may do blood tests prior to the procedure to determine how long it takes your blood to clot.
  • Tell your doctor if you have a pacemaker.
  • If you smoke, you should stop smoking as soon as possible. This may improve your chances for a successful recovery from surgery and benefit your overall health.
  • Based on your medical condition, your doctor may request other specific preparation.

What happens during coronary artery bypass?

Coronary artery bypass graft surgery (CABG) requires a stay in a hospital. Procedure may vary depending on your condition and your doctor's practices.

Generally, CABG follows this process:

  1. You will be asked to remove any jewelry or other objects that may interfere with the procedure.
  2. You will be asked to remove your clothing and will be given a gown to wear.
  3. You will be asked to empty your bladder prior to the procedure.
  4. An intravenous (IV) line will be started in your arm or hand. Additional IV catheters will be put in your neck and wrist to monitor your heart and blood pressure, as well as to take blood samples. Alternate sites for the additional catheters include under the collarbone and the groin.
  5. You will lie on your back on an operating table.
  6. The anesthesiologist will continuously monitor your heart rate, blood pressure, breathing, and blood oxygen level during the surgery. Once you are sedated (put into a deep sleep), a breathing tube will be put into your throat and you will be connected to a ventilator, which will breathe for you during the surgery.
  7. A catheter will be put into your bladder to drain urine.
  8. The skin over the surgical site will be cleaned with an antiseptic solution.
  9. Once all the tubes and monitors are in place, incisions (cuts) may be made in one or both of your legs or one of your wrists to access the blood vessel(s) to be used for the grafts. The vessel(s) will be removed, the incision(s) will be sewed shut, and dressings will be applied.
  10. The doctor will make an incision (cut) down the center of your chest from just below the Adam's apple to just above the navel.
  11. The sternum (breastbone) will be cut in half. The doctor will separate the two halves of the breastbone and spread them apart to expose your heart.

Coronary artery bypass graft surgery--on-pump procedure

  1. To sew the grafts onto the very small coronary arteries, the heart must be temporarily stopped. Tubes will be put into the heart so that your blood can be pumped through your body by a cardiopulmonary bypass machine.
  2. Once the blood has been diverted into the bypass machine for pumping, the heart will be stopped by injecting it with a cold solution.
  3. When the heart has been stopped, the doctor will perform the bypass graft procedure by sewing one end of a section of vein over a tiny opening made in the aorta, and the other end over a tiny opening made in the coronary artery just below the blockage. If the internal mammary artery inside your chest is being used as a bypass graft, the lower end of the artery will be cut from inside the chest and sewn over an opening made in the coronary artery below the blockage.
  4. You may have more than one bypass graft performed, depending on how many blockages you have and where they are located. After all the grafts have been completed, the doctor will closely check them as blood runs through them to make sure they are working.
  5. Once the bypass grafts have been checked, the blood circulating through the bypass machine will be allowed back into your heart and the tubes to the machine will be removed. Your heart may restart on its own, or a mild electric shock may be used to restart it.
  6. Temporary wires for pacing may be put into your heart. These wires can be attached to a pacemaker and your heart can be paced, if needed, during the initial recovery period.

Coronary artery bypass surgery--off-pump procedure

  1. Once the chest has been opened, the area around the artery to be bypassed will be stabilized with a special instrument.
  2. The rest of the heart will continue to function and pump blood through the body.
  3. The cardiopulmonary bypass machine and the person who runs it may be kept on stand-by just in case the procedure need to be completed on bypass.
  4. The doctor will perform the bypass graft procedure by sewing one end of a section of vein over a tiny opening made in the aorta, and the other end over a tiny opening made in the coronary artery just below the blockage.
  5. You may have more than one bypass graft performed, depending on how many blockages you have and where they are located.
  6. Before the chest is closed, the doctor will closely examine the grafts to make sure they are working.

Procedure completion, both methods

  1. The sternum will be sewn together with small wires (like those sometimes used to repair a broken bone).
  2. The skin over the sternum will be sewn back together.
  3. Tubes will be put into your chest to drain blood and other fluids from around the heart. These tubes will be connected to a suction device to keep fluids pulled away from the heart as it heals.
  4. A tube will be put through your mouth or nose into your stomach to drain stomach fluids.
  5. A sterile bandage or dressing will be applied.

What happens after coronary artery bypass surgery?

In the hospital

After the surgery, you may be taken to the recovery room before being taken to the intensive care unit (ICU) to be closely monitored. Or, you may be taken directly to the ICU from the operating room. You will be connected to machines that will constantly display your electrocardiogram (ECG) tracing, blood pressure, other pressure readings, breathing rate, and your oxygen level. Coronary artery bypass surgery (CABG) requires an in-hospital stay of at least several days.

You will most likely have a tube in your throat to assist with breathing through a ventilator (breathing machine) until you are stable enough to breathe on your own. As you continue to wake up from the anesthesia and start to breathe on your own, the breathing machine will be adjusted to allow you to take over more of the breathing. When you are awake enough to breathe completely on your own and you are able to cough, the breathing tube will be removed. In most cases, the breathing tube is removed soon after the operation, usually the same day or by early the next morning. The stomach tube will also be removed at this time.

After the breathing tube is out, a nurse will help you cough and take deep breaths every two hours. This will be uncomfortable due to soreness, but it is extremely important that you do this in order to keep mucus from collecting in your lungs and possibly causing pneumonia. Your nurse will show you how to hug a pillow tightly against your chest while coughing to help ease the discomfort.

The surgical incision may be tender or sore for several days after a CABG procedure. Take a pain reliever for soreness as recommended by your doctor. Aspirin or certain other pain medications may increase the chance of bleeding. Be sure to take only recommended medications.

You may be on special IV drips to help your blood pressure and your heart, and to control any problems with bleeding. As your condition stabilizes, these drips will be gradually decreased and turned off.

Once the breathing and stomach tubes have been removed and you are stable, you may start to drink liquids. Your diet may be gradually advanced to more solid foods as you are able to tolerate them.

When your doctor determines that you are ready, you will be moved from the ICU to a post-surgical nursing unit. Your recovery will continue there. Your activity will be gradually increased as you get out of bed and walk around for longer periods. You can eat solid foods as soon as you can tolerate them.

Arrangements will be made for you to go home and a follow-up visit with your doctor will be scheduled.

At home

Once you are home, it will be important to keep the surgical area clean and dry. Your doctor will give you specific bathing instructions. The sutures or surgical staples will be removed during a follow-up office visit, if they were not removed before leaving the hospital.

You should not drive until your doctor tells you to. Other activity restrictions may apply.

Notify your doctor if you have any of the following:

  • Fever and/or chills
  • Redness, swelling, or bleeding or other drainage from any of the incision sites
  • Increase in pain around any of the incision sites

Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.

Next steps

Before you agree to the test or the procedure make sure you know:

  • The name of the test or procedure
  • The reason you are having the test or procedure
  • The risks and benefits of the test or procedure
  • When and where you are to have the test or procedure and who will do it
  • When and how will you get the results
  • How much will you have to pay for the test or procedure