CABG (coronary artery bypass graft)

How coronary artery bypass graft is carried out

About coronary artery bypass graft (CABG)

The coronary arteries are blood vessels that supply your heart with oxygen and nutrients. If you have coronary heart disease, they are narrowed or blocked. This can starve your heart of oxygen, which causes angina (the feeling of chest pain, chest tightness and breathlessness).

CABG surgery aims to bypass the blocked arteries to increase blood flow to your heart muscle. In the operation, your surgeon will attach a new blood vessel (a graft) from your aorta (the main artery leaving your heart) to a point in the coronary artery that is beyond the blockage. Your surgeon will take blood vessels (arteries or veins) from your chest wall, leg or arm to create one or more grafts.

CABG will help to manage your symptoms but it won't cure coronary heart disease, so it's possible that blockages may recur either in the grafts or in other coronary arteries. You might then need to have further surgery, although this is relatively uncommon. You may need to make lifestyle changes to help prevent your condition from getting worse.

What are the alternatives to coronary artery bypass graft (CABG)?

There are several alternative treatments, which include the following.

  • Medicines, such as calcium channel blockers, beta-blockers, statins and antiplatelets may improve your symptoms or prevent your condition from getting worse.
  • A coronary angioplasty is a procedure in which your surgeon will insert a plastic tube called a catheter into a blood vessel (either in your groin or your wrist). A balloon that is attached to the catheter is then used to open up (dilate) the narrowed arteries so that blood flows more easily to your heart muscle. Often a stent (a small metal tube) is used to help keep the artery open.

Your treatment will depend on the condition of your coronary arteries. Your surgeon will advise you which treatment is most suitable for you.

Preparing for a coronary artery bypass graft (CABG)

Your surgeon will explain how to prepare for your operation. For example, if you smoke you will be asked to stop, as smoking increases your risk of getting a chest and wound infection, which can slow your recovery.

CABG usually requires a hospital stay of about five days and it’s usually done under general anaesthesia. This means that you will be asleep during the operation.

If you’re having a general anaesthetic, you will be asked to follow fasting instructions. This means not eating or drinking, typically for about six hours beforehand. However, it's important to follow your surgeon or anaesthetist's advice.

You may be asked to wear compression stockings after the operation to help prevent blood clots forming in the veins in your legs. You may need to have an injection of an anticlotting medicine called heparin as well as, or instead of, wearing compression stockings.

Your surgeon will discuss with you what will happen before, during and after your procedure, and any pain you might have. This is your opportunity to understand what will happen, and you can help yourself by preparing questions to ask about the risks, benefits and any alternatives to the procedure. This will help you to be informed, so you can give your consent for the procedure to go ahead, which you may be asked to do by signing a consent form.

What happens during coronary artery bypass graft (CABG)?

The procedure may take three to four hours.

Your surgeon will first prepare the graft(s). If your surgeon is going to remove a blood vessel from your leg, he or she will make a cut along the inside of your leg, between your ankle and groin to reach the vein. Alternatively your surgeon may use an artery in your forearm as a graft and will make a cut from your wrist to your elbow to remove the vein or artery.

To reach your heart, your surgeon will make a cut about 25cm (10 inches) long, down the middle of your breastbone (sternum) and will open your chest. If your surgeon is to use an artery from your chest wall (the mammary artery), he or she will remove it from behind your breastbone.

Your surgeon may attach the new grafts while your heart is still beating. This type of surgery is called off-pump or beating heart CABG. Alternatively he or she will temporarily stop your heart and divert your blood to a heart-lung (bypass) machine. This will help to maintain oxygen levels in your blood during the operation.

Your surgeon will attach the grafts and restart your heart (if it was stopped in the operation). Your surgeon will rejoin your breastbone using stainless steel wires and will close the skin on your chest, often with dissolvable stitches.

Keyhole surgery

CABG can be done using keyhole surgery (minimally invasive surgery – also called mini heart bypass surgery).

If your surgeon is going to remove a blood vessel from your leg, he or she will make small cuts near your knee and pass special instruments through the cuts to take the vein. Your surgeon will also insert a tube-like telescopic camera, which will send pictures to a monitor so your surgeon can see inside your leg. This keyhole technique is called endoscopic saphenous vein harvesting.

To reach your heart, your surgeon will make two or three small cuts in your chest and will pass special instruments through the cuts to perform the operation. Your surgeon will control robotic arms to do the surgery. A tube-like telescopic camera will be attached to the robotic arms and your surgeon will look at a monitor to see inside your chest. This method is called totally endoscopic robotically-assisted CABG.

Keyhole surgery isn't suitable for everybody – your surgeon will advise you if it's appropriate for you.

What to expect afterwards

After your operation, you will be taken to the intensive care unit (ICU) and will be closely monitored for about 24 hours before you go back to your ward.

When you wake up you will be connected to machines that record the activity of your heart, lungs and other body systems. These might include a ventilator machine to help you breathe.

You may need pain relief to help with any discomfort as the anaesthetic wears off.

If you had open surgery, you may have a catheter to drain urine from your bladder into a collection bag. You may also have tubes running out from the wound. These drain fluid into another bag and are usually removed after a day or two.

You may also be wearing compression stockings on your legs to help maintain circulation. You will be encouraged to get out of bed and move around as this will help prevent chest infections and blood clots developing in your legs.

A physiotherapist (a health professional who specialises in maintaining and improving movement and mobility) will usually visit you every day to guide you through exercises designed to help your recovery.

When you're ready to go home, you will need to arrange for someone to drive you home. Try to have a friend or relative stay with you for the first week or so.

Your nurse will give you some advice about caring for your healing wounds before you go home. You may be given a date for a follow-up appointment.

The wires holding your breastbone together are permanent. The length of time your dissolvable stitches in your skin will take to disappear depends on what type you have. For this procedure, they should usually dissolve in about six to eight weeks.

Recovering from coronary artery bypass graft (CABG)

It usually takes about two to three months to make a full recovery from CABG, but this varies between individuals, so it’s important to follow your surgeon’s advice.

If you need pain relief, you can take over-the-counter painkillers such as paracetamol or ibuprofen. Always read the patient information leaflet that comes with your medicine and if you have any questions, ask your pharmacist for advice.

Your breastbone should take about six to eight weeks to heal. Don't lift heavy objects or do any strenuous activity until the breastbone has fully healed. Your surgeon will give you advice about how soon you can return to work and how to exercise safely.

Follow your surgeon's advice about driving. Don't drive for at least a month and after this time you must be confident that you could perform an emergency stop without discomfort. If you drive a lorry or a bus, you need to notify the DVLA about your operation and you will be disqualified from driving for three months. You will need to take an exercise test before you’re allowed to drive again.

What are the risks?

As with every procedure, there are some risks associated with CABG. We have not included the chance of these happening as they are specific to you and differ for every person. Ask your surgeon to explain how these risks apply to you.


These are the unwanted but mostly temporary effects you may get after having the procedure. Side-effects of CABG include:

  • soreness, swelling and bruising around your healing wound – this can last two months
  • scarring – you will have permanent scars, which will be pink and noticeable at first, but usually fade over time


Complications are when problems occur during or after the procedure. The possible complications of any operation include an unexpected reaction to the anaesthetic, infection, excessive bleeding or developing a blood clot, usually in a vein in the leg (deep vein thrombosis, DVT). Specific complications of CABG are rare but can include:

  • a heart attack
  • stroke
  • kidney failure

The complications of CABG can occasionally be life threatening. However, it's important to consider that having no treatment, or an alternative treatment, may have a higher risk.

If you have keyhole surgery, there's a chance your surgeon may need to convert to open surgery if it's impossible to complete the operation safely using the keyhole technique.

What can I do to prevent my arteries narrowing?


To help prevent your arteries narrowing you can take medicines and make lifestyle changes. That way you may not need surgery to treat coronary heart disease.


If you have coronary heart disease, it's not possible to reverse the damage that has already been done. If you have angina (the feeling of chest pain, chest tightness and breathlessness), you may be able to manage your symptoms with medicines. Medicines for angina include:

  • beta-blockers (eg atenolol, bisoprolol)
  • long-acting nitrates (eg isosorbide mononitrate)
  • calcium-channel blockers (eg nifedipine)
  • potassium-channel activators (eg nicorandil)
  • ivabradine (Procoralan)
  • aspirin
  • statins (eg simvastatin)

These medicines aren't suitable for everyone. Ask your doctor if they are an option for you.

Lifestyle changes may help to prevent your condition from getting worse. These include:

  • giving up smoking
  • getting medical treatment to reduce your blood pressure and cholesterol levels, if they’re high
  • maintaining a healthy weight and eating a balanced diet
  • staying active

Ask your doctor for more advice on how to make changes to keep your heart healthy.

My doctor says that I may be able to have 'off-pump' coronary artery bypass graft (CABG). What is this?


'Off-pump' CABG (OPCAB) or 'beating heart surgery', is an alternative technique to conventional CABG that doesn't require you to be connected to a heart-lung (bypass) machine.


In a conventional CABG operation your heart will be stopped using medicines that contain potassium. Your heart and lungs will then be connected to a bypass machine that will take over to add oxygen to your blood and maintain your circulation.

OPCAB is an alternative technique where your heart continues to beat as your surgeon performs the bypass grafts. OPCAB is thought to be just as effective as a traditional CABG operation but may have a slightly lower risk of complications. However, research is ongoing to determine the safety of OPCAB and whether it’s as effective as the traditional technique.

Since my coronary artery bypass graft (CABG) I have been feeling depressed. Is this normal?


Yes. Feeling depressed, unhappy or anxious is often a natural reaction to having major surgery. 


After your surgery you may find that you feel depressed or unhappy. This is quite common and you may even find that you experience a range of emotions, from being happy that the operation is over to being sad that it will take time to recover.

It's a good idea to have someone stay with you for the first week or two to keep you company and to take care of you. If you live alone, it should be possible to arrange care visits from a nurse.

When you leave hospital, notify your GP so that he or she can help to provide you with any care that you may need.