CABG (Coronary Artery Bypass Grafting): When & How It's Done

CABG, short for coronary artery bypass grafting, is a surgical procedure that restores normal blood flow to the heart muscle. It’s performed by using a vein or artery from another part of the body, most often the saphenous vein from the leg, to create a new pathway for blood to travel from the aorta to the heart muscle.

This surgery helps improve circulation when the coronary arteries become blocked by fatty deposits, restricting blood flow to the heart. It’s typically recommended when other treatments, like angioplasty or medications, are not effective enough to relieve symptoms or improve heart function.

CABG is performed by a cardiac surgeon in a hospital under general anesthesia. According to the American Heart Association (AHA), coronary artery bypass grafting can significantly improve blood flow to the heart, reduce chest pain, and lower the risk of future heart attacks for people with severe coronary artery disease. 

When CABG is recommended

Doctors may recommend CABG in situations such as:

• Blocked or narrowed coronary arteries

• Multiple narrowed arteries in the heart

• Blockage in the left main coronary artery

• Artery blockages that cannot be treated with angioplasty

• Unsuccessful angioplasty

• Complex coronary artery disease

• Chest pain (angina) caused by several narrowed arteries

• Emergency treatment after a heart attack or during cardiogenic shock

CABG is usually considered when more than two arteries are affected, especially if one is a major vessel such as the left anterior descending artery or the left coronary trunk. The decision is made jointly by the doctor and the patient, based on overall health and test results.

Preparing for CABG

Before the procedure, the cardiologist will order several tests, such as an electrocardiogram, blood and urine tests, a chest X-ray, and a surgical risk evaluation.

Patients are generally advised to stop smoking and avoid alcohol for at least a month before surgery. It’s also important to inform the doctor about any ongoing medications, as some can interfere with anesthesia, increase bleeding risk, or delay recovery.

Patients should discuss any allergies or other health problems and take the opportunity to ask questions about what to expect before, during, and after CABG.

How CABG is done

CABG usually takes about five hours and is performed under general anesthesia. The main steps include:

• Inserting an IV line to provide fluids, medications, and anesthesia

• Inserting a breathing tube into the trachea to assist with breathing

• Connecting the patient to a heart-lung machine (if needed) to maintain oxygen flow while the heart is temporarily stopped

• Removing a segment of the saphenous vein from the leg

• Making an incision in the middle of the chest and opening the sternum to access the heart

• Cooling the heart and injecting a protective solution called cardioplegia to reduce the risk of tissue damage

• Identifying the blocked arteries and determining where to place the new grafts

• Sewing the harvested vein (or another artery such as the internal mammary or radial artery) from the aorta to the blocked coronary artery to restore normal blood flow

• Closing the chest with special sutures and dressing both the chest and leg incisions

After surgery, the breathing tube remains in place for several hours. The patient is transferred to the intensive care unit (ICU) for close monitoring, with chest drains inserted to remove residual blood.

Although the saphenous vein is the most common vessel used in CABG, arteries from the chest (internal mammary arteries) may also be used for longer-lasting results. When these arteries are used, the procedure is sometimes called a mammary bypass.

Impact on leg circulation

Removing part of the saphenous vein generally does not cause circulation problems in the leg. Blood continues to flow through other veins, and over time, the body naturally forms new blood vessels (a process called revascularization)to replace the removed vein segment.

Recovery after CABG

After CABG, the patient typically stays in the ICU for 2 to 3 days for observation to prevent complications such as bleeding, infection, or irregular heartbeat.

Once stable, the person is moved to a hospital room and continues to receive pain relievers to manage chest discomfort. Light physical therapy, walking, and breathing exercises are introduced early to promote recovery.

Recovery time

Recovery from CABG can take 4 to 6 weeks, depending on overall health and healing progress. Following medical recommendations closely is essential to avoid complications and ensure a smooth recovery.

Home care after CABG

After being discharged, patients should follow daily care instructions, such as:

• Taking prescribed medications exactly as directed

• Avoiding driving, heavy lifting, and smoking

• Taking warm showers daily, washing the incision with mild soap, and drying gently with a clean towel

• Keeping the incision clean and dry, and using antiseptics as advised by the doctor

• Wearing compression stockings during the day and removing them at night

• Taking short walks around the house to promote circulation

• Monitoring blood pressure twice a day and recording the results for follow-up visits

• Eating a balanced diet rich in fresh fruits, vegetables, and whole grains

After about three months, most people can gradually return to their usual activities. Attending all follow-up appointments and undergoing recommended heart tests are essential for proper recovery.

Risks of CABG

The main risks of CABG include infection, bleeding, irregular heartbeat, or heart attack. These complications are more likely in people with other health conditions such as kidney disease, additional heart problems, or when surgery is performed as an emergency.

Following all medical guidance significantly lowers these risks. In most cases, the benefits of CABG (including improved circulation, reduced chest pain, and a lower risk of heart attack) far outweigh the potential complications.