Coronary artery bypass graft


A coronary artery bypass graft (CABG) is a surgical procedure used to treat coronary heart disease.

It diverts blood around narrowed or clogged parts of the major arteries to improve blood flow and oxygen supply to the heart. 

Around 20,000 coronary artery bypass grafts are carried out in England every year. Most of these are carried out in men, and around 80% are used to treat people who are at least 60 years of age.

Why they’re carried out

Like all organs in the body, the heart needs a constant supply of blood. This is supplied by 2 large blood vessels called the left and right coronary arteries.

Over time, these arteries can become narrowed and hardened by the build-up of fatty deposits called plaques. This process is known as atherosclerosis. People with atherosclerosis of the coronary arteries are said to have coronary heart disease.

Your chances of developing coronary heart increase with age. You’re also much more likely to be affected if:

  • you smoke
  • you’re overweight or obese
  • you have a high-fat diet

Coronary heart disease can cause angina, which is chest pain that occurs when the supply of oxygen-rich blood to the heart becomes restricted. While many cases of angina can be treated with medication, severe angina may require a coronary artery bypass graft to improve the blood supply to the heart.

Another risk associated with coronary heart disease is the possibility of one of the plaques in the coronary artery rupturing (splitting), creating a blood clot. If the blood clot blocks the blood supply to the heart, it can trigger a heart attack. Therefore, a coronary artery bypass graft may also be recommended to reduce your chances of having a heart attack.

The procedure

A coronary artery bypass graft involves taking a blood vessel from another part of the body – usually the chest, leg or arm – and attaching it to the coronary artery above and below the narrowed area or blockage. This new blood vessel is known as a graft.

The number of grafts needed will depend on how severe your coronary heart disease is and how many of the coronary blood vessels are narrowed.

A coronary artery bypass graft is carried out under general anaesthetic, which means you’ll be unconscious during the operation. It usually takes between 3 and 6 hours.


Most people will need to stay in hospital for at least 7 days after having a coronary artery bypass graft.

Recovering takes time and everyone recovers at slightly different speeds. Generally, you should be able to sit in a chair after 1 day, walk after 3 days and walk up and down stairs after 5 or 6 days.

When you go home, you’ll need to take things easy for a few weeks. You should be able to return to most of your normal activities after about 6 weeks, including working, driving, and having sex – most people make a full recovery within 12 weeks.

Risks of surgery

As with all types of surgery, a coronary artery bypass graft carries a risk of complications.

These are usually relatively minor and treatable, such as an irregular heartbeat or a wound infection, but there’s also a risk of serious complications such as a stroke or heart attack.

Overall, more than 95% of people who have a coronary artery bypass graft will live for at least 1 year, and around 90% will live at least 5 years.

After surgery

After having a coronary artery bypass graft, most people will experience a significant improvement in symptoms such as breathlessness and chest pain, and their heart attack risk will be lowered.

However, it’s important to be aware that a coronary artery bypass graft isn’t a cure for coronary heart disease. If you don’t make lifestyle changes, such as eating a healthy diet and exercising regularly, your grafted arteries will also eventually become hardened and narrowed.

In some cases, a coronary artery bypass graft may need to be repeated or you may need a procedure to widen your arteries using a small balloon and a tube called a stent (coronary angioplasty).


A coronary angioplasty is the main alternative to a coronary artery bypass graft. It’s a less invasive operation where a long, flexible hollow plastic tube called a catheter is inserted into a blood vessel in your arm or groin.

A balloon attached to the catheter is then inflated to widen the artery and a small metal tube called a stent is often used to help keep the artery open.

It usually takes less time to recover from a coronary angioplasty than from a coronary artery bypass graft, but there’s a higher chance that the procedure will need to be repeated.

Also, a coronary angioplasty may not be recommended if multiple coronary arteries have become blocked and narrowed or the structure of the blood vessels near your heart is abnormal.

Getting ready

It’s a good idea to be well prepared before going into hospital to have a coronary artery bypass graft (CABG).

You may find the advice below useful:

  • Get informed – find out as much as you can about what your operation involves. Your hospital may provide written information
  • Arrange help – ask a friend or relative to help you at home for a week or two after coming home from hospital
  • Sort out transport – arrange for a friend, relative or a taxi to take you to and from the hospital
  • Prepare your home – before going for your operation, put your TV remote control, radio, telephone, medications, tissues, address book and glasses on a table next to where you’ll spend most of your time when you come out of hospital
  • Stock up – stock up on food that’s easy to prepare, such as frozen ready meals, cans, and staples like rice and pasta, or prepare your own dishes to freeze and reheat during your recovery
  • Clean up – before going into hospital, have a long bath or shower, cut your nails (don’t forget to take off any nail polish) and wash your hair. Wear freshly washed clothes to help prevent taking unwanted bacteria into hospital, which can increase your risk of developing complications

Pre-admission assessment

Before surgery, you’ll attend a pre-admission clinic, where you’ll be seen by a member of the team who will be looking after you in hospital.

At this clinic, you’ll have a physical examination and be asked for details of your medical history. You may also have some tests such as a chest X-ray, blood tests and an electrocardiogram (ECG). During an ECG, small electrodes are put on your arms, legs and chest to record the electrical signals produced by your heart.

You’ll usually be told more about the operation during your visit to the pre-admission clinic. This is a good time to ask any questions you have about the procedure, although you can discuss concerns at any time.

While at the pre-admission clinic, you’ll also be asked:

  • whether you’re taking any tablets or other types of medication – it helps if you bring details with you of anything you’re taking (perhaps bring the packaging with you)
  • about previous anaesthetics you’ve had, and whether you had any problems with these, such as feeling sick
  • whether you’re allergic to anything

You’ll be advised to stop smoking if you smoke. This is because smoking increases your chances of developing a serious chest infection and slows down the time your wounds will take to heal. Smoking can also increase your risk of getting blood clots.

What should I take into hospital?

When getting ready for your stay in hospital, you may wish to pack:

  • a change of nightclothes and a dressing gown
  • some comfortable shoes or slippers (preferably a pair that are easily adjustable, as your feet may swell temporarily after the operation)
  • something comfortable and easy to wear during the day
  • toiletries
  • medication that you normally take
  • books, magazines, crosswords and other things to help pass the time during your recovery
  • healthy snacks for between meals
  • your address book and important phone numbers

Different hospitals tend to have different rules about personal electronic equipment. You may want to check with your hospital about their policy on the use of mobile phones, MP3 players, laptops and tablets during your hospital stay.

You’ll have a bedside locker for your personal belongings, but it’s a good idea to avoid taking any unnecessary valuables into hospital.

How it’s performed

Before your coronary artery bypass graft (CABG), your surgeon will discuss every aspect of the procedure with you.

This will give you the opportunity to ask any questions to make sure you understand the procedure fully.

As the procedure is carried out using a general anaesthetic (where you’re unconscious during the operation), you must not eat or drink for at least 6 hours before the operation. You may be able to have occasional sips of water until 2 hours before the operation.

During the operation

Coronary artery bypass graft surgery usually lasts 3 to 6 hours. However, it may take longer depending on how many blood vessels are being grafted.

Blood vessels can be taken from your leg (saphenous vein), inside your chest (internal mammary artery) or your arm (radial artery). Other blood vessels in these areas are able to compensate for the loss of these blood vessels after the operation.

The number of blood vessels used will depend on how severe your coronary heart disease is and how many of the coronary blood vessels have become narrowed. Most people will need 3 or 4 vessels grafted. If you need 2, 3 or 4 grafts, you may hear your operation referred to as a ‘double’, ‘triple’ or ‘quadruple’ bypass.

One of the graft vessels is usually your internal mammary artery. Surgeons prefer to use this vessel because it doesn’t narrow over time, unlike the blood vessels taken from your leg or arm.

Once all the graft vessels have been removed, your surgeon will make a cut (incision) down the middle of your chest so they can divide your breastbone (sternum) and access your heart.

During the procedure, your blood may be re-routed to a heart-lung bypass machine. This takes over from your heart and lungs, pumping blood and oxygen through your body. Your heart will be temporarily stopped using medication while your surgeon attaches the new grafts to divert the blood supply around the blocked artery.

After the grafts have been attached, your heart will be started again using controlled electrical shocks. Your breastbone will then be fixed together using permanent metal wires and the skin on your chest sewn up using dissolvable stitches.

Newer surgical techniques

Off-pump coronary artery bypass surgery (OPCAB)

More surgeons are now performing off-pump coronary artery bypass surgery (OPCAB), which is a variation of the conventional procedure.

A coronary artery bypass graft is often described as on-pump surgery because it involves using a heart-lung bypass machine to pump blood and oxygen around your body during the procedure, while the heart is temporarily stopped.

During OPCAB, your heart is still beating while the new blood vessel grafts are attached and a heart-lung bypass machine isn’t used.

According to the National Institute for Health and Care Excellence (NICE), the procedure works as well as a coronary artery bypass using a pump.

The benefits of OPCAB are:

  • it often takes less time to perform than the conventional procedure 
  • it can reduce your chance of bleeding during the surgery
  • you may be less likely to develop certain serious complications after surgery, such as a stroke
  • your stay in hospital will usually be shorter

The main disadvantage is that OPCAB is more technically demanding because the grafted vessels have to be delicately connected while the heart is beating. This means the procedure may be too difficult to perform if a large number of blood vessels need to be grafted.

For the same reason, if emergency surgery is required, there may not be ready access to a surgeon with the training required to perform an OPCAB.

Read the NICE guidelines about off-pump coronary artery bypass grafting.

Endoscopic saphenous vein harvesting (ESVH)

Endoscopic saphenous vein harvesting (ESVH) is a new method of removing the veins from your legs. Rather than making a large incision in your leg, the surgeon makes a number of small incisions near your knee. This is known as ‘keyhole’ surgery.

A special device called an endoscope will be inserted into the incision. An endoscope is a thin, long flexible tube with a light source and video camera at one end, so that images of the inside of your body can be relayed to an external television monitor.

The endoscope allows the surgeon to locate your saphenous vein. Surgical instruments can also be passed along the endoscope to remove a section of the vein. Nearby tissue is then sterilised with antibiotic fluid and the incision is healed.

The main advantages of this technique are that there’s likely to be less scarring and your leg will usually heal quicker after the operation. However, as this is a relatively new technique, there are uncertainties about how well the grafts work in the years after the procedure.

Read the NICE guidelines about endoscopic saphenous vein harvest for coronary artery bypass grafting.

Totally endoscopic robotically assisted coronary artery bypass (TECAB) grafting

Totally endoscopic robotically assisted coronary artery bypass (TECAB) grafting is another new technique in heart surgery. It’s a minimally invasive (keyhole) method of performing a heart bypass.

During a TECAB grafting procedure, the surgeon deflates your lungs and makes a number of small incisions between your ribs. Robotic arms, controlled by the surgeon, are used to carry out the surgery. An endoscope is attached to the robotic arms so the surgeon can see inside your body and view the results of the surgery on a screen.

TECAB grafting can be carried out using a heart-lung bypass machine or it can be done ‘off-pump’.

There are lower rates of wound infection with this type of surgery, plus minimal scarring and a faster recovery time. However, as this is a new technique that’s only been carried out on a small number of people, it’s difficult to assess how effective and safe it is in the short and long term, and how the outcomes compare with other types of surgery.

If you’re considering having TECAB, it’s important you understand there are still uncertainties about how safe the procedure is and how well it works.

Read the NICE guidelines about totally endoscopic robotically assisted coronary artery bypass grafting.


You’ll usually need to stay in hospital for around 7 days after having a coronary artery bypass graft (CABG), so medical staff can closely monitor your recovery.

During this time, you may be attached to various tubes, drips and drains that provide you with fluids and allow blood and urine to drain away. These will be removed as you get better.

It’s likely you’ll feel some discomfort and grogginess after the procedure, but you’ll be given painkillers to help relieve any pain. Tell your doctor or nurse if the pain increases or if you notice any excessive bleeding.

Recovering from a coronary artery bypass graft procedure takes time and everyone recovers at slightly different speeds. Generally, you should be able to sit in a chair after 1 day, walk after 3 days and walk up and down stairs after five or 6 days.

Most people make a full recovery within 12 weeks of the operation. However, if you experience complications during or after surgery, your recovery time is likely to be longer.

At home

To ease any soreness where the cuts were made, you may need to continue taking painkillers at home for a few weeks. Wearing loose, comfortable clothing that doesn’t rub on your wounds can also help.

For the first 3 to 6weeks, you’ll probably feel tired a lot of the time. This is because your body is using a lot of energy to heal itself. By 6 weeks, you should be able to do most of your normal activities and by 3 months, you’re likely to be fully recovered.

Caring for your wound

The metal wires holding your breastbone (sternum) together are permanent. However, the stitches closing your skin will gradually dissolve over the weeks following surgery as your skin heals.

While you’re recovering in hospital, you’ll be told about how to care for your wounds at home. It’s important to keep the wounds clean and protect them from the sun while they’re healing.

You’ll have a scar where the surgeon cut down your chest, as well as where the grafted blood vessel (or vessels) was taken from. These will be red at first, but will gradually fade over time.


The team caring for you in hospital will also usually be able to advise you about any activities you need to avoid as you recover.

Generally, in the first few days after you return home from hospital, you can do light activities such as walking short distances, cooking, playing cards and board games, and lifting light objects.

After about 6 weeks, you may be well enough to do slightly more strenuous activities, such as driving, carrying children, carrying heavier objects (but not very heavy objects, such as bags of compost or cement), vacuuming, mowing the lawn and having sex.

The length of time you need off work varies from person to person. If you’re recovering well and your job isn’t physically strenuous, you can usually go back to work in about 6 to 8 weeks. However, you’ll normally need more time off if you experience any complications or your job involves a lot of standing and lifting.

While recovering, it’s best to try to build up your activities gradually over time and make sure you take regular rests when you feel tired.

Side effects of surgery

After you’ve been discharged from hospital, you may experience some side effects as a result of the operation. These can include:

  • loss of appetite
  • constipation
  • swelling or pins and needles where the blood vessel graft was removed
  • muscle pain or back pain
  • tiredness and difficulty sleeping
  • feeling upset and having mood swings

It’s natural to feel a bit low after having bypass surgery. You’ll experience good and bad days, but it’s important to remember your recovery will take weeks rather than days.

Side effects tend to disappear within 4 to 6 weeks of the operation. A full recovery may take a few months or longer, depending on your overall health before the procedure.

If you would like some extra support and advice while you recover, speak with your GP or contact the British Heart Foundation, who can provide you with details of local heart support groups.

When to seek medical advice

Contact your GP for advice as soon as possible if you experience any of the following problems:

Call NHS 24 111 Service or contact your local out-of-hours service if you’re unable to contact your GP.

Cardiac rehabilitation

Many hospitals offer a cardiac rehabilitation programme for people who’ve had heart surgery. The programme, which usually lasts at least 6 weeks, aims to help you recover from the procedure and get back to everyday life as quickly as possible.

A member of the cardiac rehabilitation team may speak to you about this when you go into hospital to have your operation. You may be invited to join a cardiac rehabilitation programme starting a few weeks after you leave hospital.

The way cardiac rehabilitation programmes are carried out can vary widely throughout the country, but most will cover areas such as exercise, education, relaxation and emotional support.

The British Heart Foundation has more information about cardiac rehabilitation.

Life after a coronary artery bypass graft

When you’ve fully recovered from your operation, it’s important to adopt a healthy lifestyle to reduce your risk of developing further heart problems in the future. For example, you should:

You should also continue to take any medications you’ve been prescribed.


As with all types of surgery, a coronary artery bypass graft (CABG) carries risks of complications.

Some of the main complications associated with a coronary artery bypass graft are described below.

Irregular heartbeat

Up to 1 in every 3 people who have a coronary artery bypass graft will develop a problem called atrial fibrillation, a condition that causes an irregular and often abnormally fast heart rate.

However, this isn’t usually serious and can normally be easily treated with a course of medication.


There’s a chance that the wounds in your chest and arm or leg (depending on where the grafted blood vessels were removed) could become infected after a coronary artery bypass graft.

This is estimated to occur in up to 1 in every 25 people who have the procedure.

There’s also a smaller chance of more serious infections affecting your lungs or the inside of the chest after having a coronary artery bypass graft.

Most infections that do develop after the procedure can usually be treated successfully with antibiotic tablets or injections.

Reduced kidney function

Less than 1 in every 20 people who have a coronary artery bypass graft will experience reduced kidney function after surgery. In most cases, this is only temporary and the kidneys begin working normally after a few days or weeks.

In rare cases, you may need to have temporary dialysis until your kidneys recover. This involves being attached to a machine that replicates the functions of the kidneys.

Brain-related problems

Up to 1 in every 20 people experience some problems with their memory after a coronary artery bypass graft and also find it difficult to concentrate on things like reading a book or newspaper. This will usually improve in the months following the operation, but it can sometimes be permanent.

There’s also a risk of serious problems affecting the brain during or after a coronary artery bypass graft, such as a stroke. It’s estimated that around 1 in every 50 people who has a coronary artery bypass graft will experience a stroke, which can leave you with permanent movement, speaking and swallowing problems, and in some cases can be fatal.

Heart attacks

Both the heart and the coronary arteries that supply the heart with blood are in a vulnerable state after a coronary artery bypass graft, particularly during the first 30 days after surgery.

Around 1 in every 15-50 people who have a coronary artery bypass graft are estimated to have a heart attack during surgery, or shortly afterwards. Heart attacks are the leading cause of death after a coronary artery bypass graft.

Who’s most at risk?

Following a coronary artery bypass graft, there are several factors that increase your risk of developing complications, including:

  • your age – your risk of developing complications after surgery increases as you get older
  • having another serious long-term health condition – having a condition such as diabetes, chronic obstructive pulmonary disease or severe chronic kidney disease can increase your risk of complications
  • being a woman – women tend to develop coronary artery disease later than men; it’s thought this may lead to a higher risk of experiencing complications because they’re generally older at the time of surgery
  • having emergency surgery to treat a heart attack – emergency surgery is always riskier because there’s less time to plan the surgery, and the heart can be seriously damaged from the heart attack
  • having 3 or more vessels grafted – the more complex the operation, the greater the chance that complications will occur
  • being obese – if you’re obese the surgeon will have to make a deeper incision to gain access to your heart, and deeper incisions carry a higher risk of becoming infected.

Your surgical team will be able to provide you with more detailed information about any specific risks before you have surgery.

Life after a coronary artery bypass

A coronary artery bypass graft (CABG) isn’t a cure for heart disease, so it’s important to adopt a healthy lifestyle and continue taking any prescribed medication after the operation to reduce your risk of getting heart problems in the future.

Healthy lifestyle

There are a number of lifestyle changes you can make after having a coronary artery bypass graft to help reduce your risk of further heart problems. These are described below.

Healthy diet

An unhealthy diet can increase your chances of developing heart problems after a coronary artery bypass graft. To reduce this risk, you should ensure your diet is low in saturated fat and salt, but high in fibre and omega-3 (a fatty acid that can help reduce your cholesterol levels).

Examples of foods you should try to avoid include:

  • meat pies
  • sausages and fatty cuts of meat
  • butter, lard and ghee (a type of butter often used in Indian cooking)
  • cream
  • cakes and biscuits

Instead, you should try to eat:

  • starchy foods, such as wholegrain rice, bread and pasta
  • fruit and vegetables – ideally five portions a day
  • oily fish, such as mackerel and sardines

Also, cut down on the amount of salt you add to your food and check the nutrition labels on food when shopping to find products with the lowest levels of salt.

Read more about healthy eating.

Exercise regularly

Once you’ve fully recovered from the effects of surgery, you should exercise regularly to reduce your risk of developing further heart problems.

Adults should do at least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity every week. Moderate-intensity means an activity that’s strenuous enough to leave you slightly breathless.

Examples of moderate-intensity aerobic activities include:

  • fast walking
  • cycling on level ground or with few hills
  • doubles tennis
  • pushing a lawn mower
  • hiking

If you find it difficult to achieve 150 minutes of activity a week, start at a level you feel comfortable with (for example, around 10 minutes of light exercise a day) and gradually increase the duration and intensity of your activity as your fitness starts to improve.

Read more about the physical activity guidelines for adults (19 to 64).

Lose weight

If you’re overweight or obese, you can reduce your risk of further heart problems by trying to reach a healthy weight. To find out whether you need to lose weight you can read more about BMI.

The best way to lose weight is to make sure you have a healthy diet and exercise regularly. 

Stop smoking

Smoking can significantly increase your risk of developing heart problems because it narrows your arteries and raises your blood pressure.

If you want to stop smoking, you can call the Quit Your Way Scotland service on 0800 84 84 84. Specially trained helpline staff will offer you free expert advice and encouragement.

If you’re committed to giving up smoking but don’t want to be referred to a stop smoking service, your GP should be able to prescribe medication to help with withdrawal symptoms you may experience after giving up.

Moderate your alcohol consumption

If you drink alcohol, don’t exceed the recommended limits.

  • men and women are advised not to regularly drink more than 14 units a week
  • spread your drinking over 3 days or more if you drink as much as 14 units a week

1 unit of alcohol is roughly half a pint of normal-strength lager or a single measure (25ml) of spirits. A small glass of wine (125ml) contains about 1.5 units of alcohol.

Regularly exceeding the recommended alcohol limits can raise your blood pressure and cholesterol level, increasing your risk of heart problems.

Read more about tips on cutting down your alcohol intake.

Taking medication

You’ll probably need to take less medication after having a coronary artery bypass graft, but you may still need to take some to reduce your risk of further problems.

Some of the medications you may be prescribed are described below.

Anticoagulants and antiplatelets

Anticoagulants and antiplatelets are types of medication that reduce the risk of blood clots forming.

Examples of these medications include:

After a coronary artery bypass graft, you may be prescribed one of these medications to take for a few months, or for the foreseeable future.

If you’re prescribed one of these medications after your operation, it’s important to take it because they can reduce your risk of serious problems such as heart attacks.


Statins are a type of medication used to lower your blood cholesterol level. This will help prevent further damage to your coronary arteries and should reduce your risk of problems such as heart attacks.

Examples of statins include:

  • atorvastatin (Lipitor)
  • fluvastatin (Lescol)
  • simvastatin (Zocor)

In most cases, treatment with statins will be recommended for life.

Other medications

Depending on the specific reason why you had a coronary artery bypass graft, you may also be prescribed some other medications, such as beta-blockers and angiotensin-converting enzyme (ACE) inhibitors. 


If you have coronary heart disease and the arteries around your heart are severely narrowed, it may be possible to have a procedure called a coronary angioplasty instead of a coronary artery bypass graft (CABG).

Coronary angioplasty

During a coronary angioplasty, a long, flexible plastic tube called a catheter is inserted into a blood vessel, either in your groin or arm.

The tip of the catheter is guided under X-ray to the arteries that supply your heart, to the point where the narrowing of the artery has occurred.

A balloon attached to the catheter is inflated to widen the artery and a small metal tube called a stent is often left in the affected section of artery to help keep it open.

It’s uncommon for a coronary angioplasty to have serious complications. Heart attacks, strokes and deaths are estimated to occur in less than 1 in every 100 cases.

It’s unlikely a coronary angioplasty will be recommended if multiple coronary arteries have become blocked and narrowed. It may also not be technically possible if the anatomy of the blood vessels near your heart is abnormal.

Which procedure is best?

You may not always be able to choose between having a coronary angioplasty or a coronary artery bypass graft, but if you are it’s important to be aware of the advantages and disadvantages of each technique.

As a coronary angioplasty is minimally invasive, you’ll recover from the effects of the operation quicker than you will from a coronary artery bypass graft. Coronary angioplasty usually has a smaller risk of complications, but there’s a chance you’ll need further treatment because the affected artery may narrow again.

However, the number of people who need further treatment has fallen in recent years because of the use of special drug-eluting stents that reduce the risk of the artery narrowing again. See how a coronary angioplasty is performed for more information about these.

A coronary artery bypass graft has a longer recovery time than coronary angioplasty and a higher risk of complications. However, only 1 person in 10 who has a coronary artery bypass graft needs further treatment.

There’s also some evidence to suggest that a coronary artery bypass graft is usually a more effective treatment option for people over 65 years of age and particularly for people with diabetes.

If possible, you should discuss the benefits and risks of both types of treatment with your cardiologist and cardiac surgeon before making a decision.


In some cases, it’s possible to treat coronary heart disease with a number of different medications, such as:

These medications can help control some of the symptoms of coronary heart disease and can reduce the risk of the condition getting worse. However, a coronary artery bypass graft may be recommended if the condition is severe or there’s a particularly high risk of serious problems, such as heart attacks, because it’s a more effective treatment in these cases.

Last updated:
13 April 2023