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Coronary artery bypass graft surgery

Bypass surgery is used to get blood to part of your heart muscle when your arteries are blocked. Find out the pros and cons and what to expect when having coronary artery bypass graft surgery.

image of a normal heart next to a heart that's had a coronary artery bypass graft. The heart that's had the coronary artery bypass graft shows a blockage and new vein.

Coronary artery bypass graft surgery (CABG) is done mainly to relieve angina symptoms. The surgery improves blood flow to the heart muscle. This can result in a better quality of life with less or no angina.

Note: Bypass surgery is not a cure for heart disease. It may help control your symptoms, but it does not fix the underlying heart disease that caused the symptoms in the first place. To lower your chance of further heart problems, you will need to make and maintain changes to your lifestyle.

What happens during bypass surgery?

A blood vessel is grafted between the aorta (the main artery leading from the heart) and the coronary artery, or arteries leading to the heart muscle. This allows the blood to bypass blocked arteries and restores blood flow to the heart muscle. It is quite normal to need two to four grafts, otherwise known as a double, triple or quadruple bypass.

Your surgeon will then make a cut, about 25cm (10 inches) long, down the middle of your breastbone (sternum) and will open your ribcage to reach your heart. Your surgeon may attach the new grafts while your heart is still beating, but it's more common to temporarily stop your heart.

Your blood is then diverted to a heart-lung (bypass) machine. This takes over from your heart and lungs to add oxygen to your blood and maintain your circulation.

The grafts will be attached and your heart will be restarted. Your sternum will be rejoined using wires and the skin on your chest will be closed with dissolvable stitches.

The procedure itself takes around three hours, but may take longer depending on how many grafts need to be done. If blood vessels from your leg or arm are being used for grafts, your surgeon will remove and prepare these first.

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

You will be encouraged to get out of bed and move around as this helps prevent chest infections and blood clots in your legs. A physiotherapist will usually visit you every day to guide you through exercises designed to help your recovery. When you are ready to go home, you will need to arrange for someone to drive you home. You should try to have a friend or relative stay with you for the first 24 hours.

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 sternum together are permanent. Dissolvable stitches will disappear in seven to 10 days on their own.

The New Zealand Transport Agency medical guidelines state that you must not drive a car for at least four weeks following your surgery. You will need an assessment by a specialist to check on your condition before you return to driving.

Before you're discharged from hospital you will be invited to join a cardiac rehabilitation programme. These programmes provide practical help, advice and support to you and your family/whānau after hospital discharge. Explore our Heart Help directory to find a list of your local cardiac rehabilitation programmes.

After a bypass, you will usually feel some discomfort and have some swelling around the wound areas for a few weeks. You're likely to have permanent scars on your chest and in the area from where your graft is taken. These may fade over time.

You may suffer from poor memory and concentration, but this usually wears off gradually within six months. The most common problem after surgery is the return of chest pain (angina).

No procedure is ever completely free of risks. However, open heart surgery has been performed for many years with successful results and limited complications.

Your doctors will explain all relevant risks of this procedure to you prior to surgery. These may include:

  • Risks associated with anaesthesia
  • Death
  • Heart attack
  • Stroke
  • Excessive bleeding
  • Infection
  • Subtle problems in long-term memory, comprehension, calculation skills and concentration.

For more information about what to expect with having coronary artery bypass graft surgery, explore our PDF resource.

Get the bypass resource