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.

Why it's 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 disease 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 angina can often be treated with medicine, 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.

A coronary artery bypass graft may 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.

You should have a follow-up appointment, typically about 6 to 8 weeks after your operation.

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. If you have a heavy manual job, you may need to stay off work longer.

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.

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.

But 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.

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 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.

How long will I have to wait for surgery?

The length of time you'll have to wait to have a coronary artery bypass graft will vary from area to area.

Your GP or cardiac surgeon should be able to tell you what the waiting lists are like in your area or at the hospital you have chosen.

Ideally, you should be treated within 3 months of the decision to operate.


Getting Ready

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

Useful tips to help you prepare

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 2 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'll 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 have 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
  • medicine that you normally take
  • books, magazines, crosswords and other things to help pass the time during your recovery
  • healthy snacks for between meals

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 is it 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 asleep during the operation), you mustn't eat or drink for at least 6 hours before the operation.

You may be able to drink clear fluids like water, squash, black tea or black coffee until about 2 hours before the operation. Your care team will be able to advise you further about this.

During the operation

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

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.

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 taken from your chest (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 down the middle of your chest so they can divide your breastbone (sternum) and access your heart.

During the procedure, your blood may be rerouted 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 less invasive method of removing the veins from your legs.

Rather than making a large cut in your leg, the surgeon makes a number of small ones near your knee. This is known as keyhole surgery.

A special device called an endoscope will be inserted into the cut.

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 cut is healed.

The main advantages of this technique are that there's likely to be a:

  • shorter hospital stay
  • lower risk of leg wound infections
  • quicker recovery from CABG

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 a newer 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 cuts 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.

But 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 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 5 or 6 days.

Most people make a full recovery within 12 weeks of the operation.

But if you experience complications during or after surgery, your recovery time is likely to be longer.

You should have a follow-up appointment, typically about 6 to 8 weeks after your operation.

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 6 weeks, 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.

But 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 card and board games
  • 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
  • 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.

But 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 have 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. 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 about 3 months or longer, depending on your fitness, age and the severity of your condition.

If you'd 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

Call 999 if you:

  • have chest pain
  • have extreme shortness of breath
  • have palpitations that make you feel dizzy or faint
  • feel extremely unwell

Follow any advice that you have been given on discharge from hospital.

See a GP if you have:

  • worsening pain in or around the wound
  • redness and swelling around the wound
  • pus or blood coming from the wound
  • a very high temperature or you feel hot and shivery

Call 111 Wales if you're unable to contact your GP.

Cardiac rehabilitation

Many hospitals offer a cardiac rehabilitation programme for people who have 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.

Cardiac rehabilitation programmes 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 have 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:

  • stop smoking if you smoke
  • eat a healthy, balanced diet
  • lose weight if you're overweight or obese
  • moderate your alcohol intake
  • exercise regularly 

You should also continue to take any medications you have 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 covered on this page.

Irregular heartbeat

Some people who have a coronary artery bypass graft develop atrial fibrillation, a condition that causes an irregular and often abnormally fast heart rate.

But this isn't usually serious if found early and can normally be easily treated with a course of medication.


The wounds in your chest and arm or leg (depending on where the grafted blood vessels were removed) can become infected after a coronary artery bypass graft.

Infection can also affect 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

Some people have reduced kidney function after surgery. This is usually 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

Some 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.

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.

Some people who have a coronary artery bypass graft have a heart attack during surgery, or shortly afterwards.

Who's most at risk?

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

These include:

  • 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 (COPD) 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 cut to gain access to your heart, which has 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.

Living with

A coronary artery bypass graft (CABG) isn't a cure for heart disease.

After the operation, 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.

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 5 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.

Exercise regularly

Once you have 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 a 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.

Lose weight

If you're overweight or obese, you can reduce your risk of further heart problems by trying to reach a healthy weight.

You can use the BMI healthy weight calculator to find out whether you need to lose weight.

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, your GP will be able to refer you to the NHS Smokefree service, which will provide you with dedicated help and advice about the best ways to give up smoking.

You can also call Help Me Quit on 0808 278 2522. 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.

Drink less alcohol

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

One 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.

Taking medicine

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.

Anticoagulants and antiplatelets

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

Examples of these medications include:

  • low-dose aspirin
  • clopidogrel
  • warfarin

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)

Treatment with statins will usually be recommended for life.

Other medicines

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.

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.

But the number of people who need further treatment has fallen in recent years because of the use of special stents coated with medication that reduce the risk of the artery narrowing again.

A coronary artery bypass graft has a longer recovery time than coronary angioplasty and a higher risk of complications.

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, 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 medicines can help control some of the symptoms of coronary heart disease and can reduce the risk of the condition getting worse.

But 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.

The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website
Last Updated: 21/05/2024 13:38:35