CABG 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 chest (thoracic), leg (saphenous) or arm (radial). The graft goes around the blocked artery (or arteries) to create new pathways for oxygen-rich blood to flow to the heart.
The goals of the procedure are to relieve symptoms of coronary artery disease (including angina), enable the patient to resume a normal lifestyle and to lower the risk of a heart attack or other heart problems. bypass surgery may be performed in combination with other heart surgeries, when necessary, such as valve surgery, aortic aneurysm surgery or surgery to treat atrial fibrillation (an irregular heart beat).
Who is eligible to receive coronary artery bypass graft surgery?
Diagnostic tests have helped your heart doctor identify the location, type and extent of your coronary artery disease. The results of these tests, the structure of your heart, your age, the severity of your symptoms, the presence of other medical conditions, and your lifestyle will help your cardiologist, surgeon and you determine what type of treatment is best.
What happens during coronary artery bypass surgery?
After general anesthesia is administered, the surgeon prepares the arteries or removes the veins to use for bypass grafts.
To bypass the blockage, the surgeon makes a small opening just below the blockage in the diseased coronary artery. If a saphenous (leg) vein or radial (arm) artery is used, one end is connected to the coronary artery and the other to the aorta. If an internal thoracic artery is used, one end is connected to the coronary artery while the other remains attached to the aorta. The graft is sewn into the opening, redirecting the blood flow around this blockage.
The procedure is repeated until all affected coronary arteries are treated. It is common for three or four coronary arteries to be bypassed during surgery.
The surgeon makes an incision down the center of your chest, through your sternum to view your heart and coronary arteries.
Types of coronary artery bypass grafts
Internal thoracic arteries [also called ITA grafts or internal mammary arteries (IMA)] are the most common bypass grafts used, as they have shown the best long-term results. There are two internal mammary arteries, and in most cases, these arteries can be kept intact at their origin because they have their own oxygen-rich blood supply, and then sewn to the coronary artery below the site of the blockage. If the surgeon removes the mammary artery from its origin, it is called a “free” mammary artery. Use of the ITA graft is a standard of care for bypass grafting. It is factored into STS star-rating calculations for cardiac surgery programs. The goal is to use the ITA in all patients who are undergoing isolated coronary bypass surgery.
The radial (arm) artery is another common type of arterial graft. There are two arteries in the arm, the ulnar and radial arteries. Most people receive blood to their arm from the ulnar artery and will not have any side effects if the radial artery is used. Careful preoperative and intraoperative tests determine if the radial artery can be used. If the radial artery is used as the graft, the patient may be required to take a calcium channel blocker medication for several months after surgery. This medication helps keep the artery open. Some people report numbness in the wrist after surgery. However, long-term sensory loss or numbness is uncommon. While medium term results are good, long-term outcomes are not fully known.
The gastroepiploic artery is a branch leading to the stomach and the inferior epigastric artery to the abdominal wall are less commonly used for grafting, as they are more difficult to use, but can be a good option for specific patients.
Saphenous veins can be used as bypass grafts. Minimally invasive saphenous vein removal does not require a long incision. One to two incisions are made at the knee and a small incision is made at the groin. This results in less scarring and a faster recovery. While progress has been made over the years to decrease the rate of vein graft failure, failure of vein grafts over the long term continues to be a problem.
How is the choice of graft made?
The surgeon determines the right type of bypass graft to treat your coronary artery disease. The choice depends on many factors including location of the blockage, extent of the blockage, size of the coronary arteries, availability of arteries and veins, the age of the patient and co-existing medical conditions.
Heart-Lung Bypass Machine
During surgery, the heart-lung bypass machine (called “on-pump” surgery) is used to take over for the heart and lungs, allowing the circulation of blood throughout the rest of the body. The heart’s beating is stopped so the surgeon can perform the bypass procedure on a “still” heart.
Off-pump or beating heart bypass surgery allows surgeons to perform surgery on the heart while it is still beating. The heart-lung machine is not used. The surgeon uses advanced operating equipment to stabilize (hold) portions of the heart and bypass the blocked artery in a highly controlled operative environment. Meanwhile, the rest of the heart keeps pumping and circulating blood to the body. More information about off-pump surgery
How long does the procedure last?
The surgery generally lasts from 3 to 5 hours, depending on the number of arteries being bypassed.
What are the risks?
As with any surgery, there are risks involved. Your surgical risks are related to your age, the presence of other medical conditions and the number of procedures you undergo during a single operation. Your cardiologist will discuss these risks with you before surgery; please ask questions to make sure you understand why the procedure is recommended and what all of the potential risks are.
After the grafts have been completed during the “on pump” procedure, the heart-lung machine is turned off, the heart starts beating on its own, and the flow of blood returns to normal.
Temporary pacing wires and a chest tube to drain fluid are placed before the sternum is closed with special sternal wires. Then the chest is closed with internal stitches or traditional external stitches. Sometimes a temporary pacemaker is attached to the pacing wires to regulate the heart rhythm until your condition improves.
The patient is transferred to an intensive care unit for close monitoring for about one to two days after the surgery. The monitoring during recovery includes continuous heart, blood pressure and oxygen monitoring and frequent checks of vital signs and other parameters, such as heart sounds.
Once the patient is transferred to the step-down nursing unit, the hospital stay is about 3 to 5 more days.
How will I feel after surgery?
For a while after the surgery, you may feel worse than you did before surgery. This is normal and is usually related to the trauma of surgery, not necessarily to the functioning of your heart valves. It may take you from 4 to 10 weeks to fully recover from surgery.
How you feel after surgery depends on your overall health, the results of the surgery, and how well you take care of yourself after surgery. After recovering from surgery, most patients do feel better. To some extent, how you feel will depend on how you felt before surgery.
Patients with more severe symptoms before surgery may experience a greater sense of relief after surgery. Call your doctor if you are concerned about your symptoms or rate of recovery.
Full recovery from coronary artery bypass graft surgery takes about 2 months, or may be sooner if minimally invasive surgery techniques were used. Most patients are able to drive in about 3 to 8 weeks after surgery. Your doctor will provide specific guidelines for your recovery and return to work, including specific instructions on activity and general health after the surgery.
Cardiac Rehabilitation is an important program for patients recovering from coronary artery bypass surgery. The combination of exercise, risk factor and lifestyle education, and peer support will help you recover safely, enjoyably and provide long-term benefits.
Follow Up Care
Patients after heart surgery at Cleveland Clinic see their heart surgery team a few days after discharge from the hospital. You will need to visit with a cardiologist your your primary care doctor within the first month and then at 6 to 8 weeks to make sure you are on the right medication and right dose, and your recovery is on track.
Regular follow up appointments with your cardiologist are important (even if you have no symptoms). These should be scheduled every year, or more often, as recommended by your doctor. Your appointments should include a medical exam. Diagnostic studies (such as an echocardiogram) may be repeated at regular intervals.
You should call your doctor if your symptoms become more severe or frequent. Don’t wait until your next appointment to discuss changes in your symptoms.
Importance of Making Lifestyle Changes
Coronary artery bypass graft surgery increases the blood supply to your heart, but it does not cure coronary artery disease. You will still need to decrease your risk factors by making lifestyle changes, taking medications as prescribed and following your doctor’s recommendations to prevention future disease. Lifestyle changes include:
- Quitt smoking
- Treat high cholesterol
- Manage high blood pressure and diabetes
- Exercise regularly
- Maintain a healthy weight
- Eat a heart-healthy diet
- Control stress and anger
- Take prescribed medications as directed
- Participate in a cardiac rehabilitation program, as recommended
- Follow up with your doctor for regular visits