Coronary artery bypass


Coronary artery bypass


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 CABG procedures are performed 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 old.


Why they are carried out

Like all organs in the body, the heart needs a constant supply of blood. This is supplied by two 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 and you are much more likely to be affected by the condition if you smoke, if you're overweight or obese, and if you eat 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 CABG to improve the blood supply to the heart.

Another risk associated with coronary heart disease is that one of the plaques in the coronary artery ruptures (splits), creating a blood clot. The blood clot can block the supply of blood to the heart, triggering a heart attack. Therefore, a CABG may also be recommended to reduce your chances of having a heart attack.


The procedure

A CABG 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 have become narrowed.

A CABG is carried out under general anaesthetic, which means you will be asleep during the operation. It usually takes between three and six hours.



Most people will need to stay in hospital for at least seven days after a CABG.

Recovery from a CABG takes time and everyone recovers at slightly different speeds. Generally, you should be able to sit in a chair after one day, walk after three days and walk up and down stairs after five or six days.

When you go home, you will need to take things easy for a few weeks. You will usually be able to return to most of your normal activities after about six 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 CABG carries a risk of complications.

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

Overall, more than 95% of people who have a CABG will live for at least one year and around 90% will live at least five years.


After surgery

After a CABG, 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 is important to realise that a CABG is not a cure for coronary heart disease. If you do not make lifestyle changes, such as eating a healthy diet and exercising regularly, your grafted arteries will eventually become hardened and narrowed too.

In some cases, a CABG 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).


Are there any alternatives?

The main alternative to a CABG is a coronary angioplasty. This is a less invasive operation that involves inserting a long, flexible hollow plastic tube called a catheter 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.

Recovery from a coronary angioplasty is usually faster than after a CABG, but there is a higher chance that the procedure will need to be repeated and it 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.


Preparing for a coronary artery bypass graft 

Before going into hospital to have a coronary artery bypass graft (CABG), it is a good idea to make some preparations.

You may find the advice below useful:

Get informed – Find out as much as you can about what is involved in your operation. Your hospital may provide written information.

Arrange help – Line up a friend or relative to help you at home for a week or two after coming home from hospital.

Sort out transport – Arrange for either a friend, a relative or a taxi to take you to and from the hospital.

Prepare your home – Before you go for your operation, put your TV remote control, radio, telephone, medications, tissues, address book and glasses on a table next to where you will spend most of your time when you come out of hospital.

Stock up – Get in a stock of food that is easy to prepare (for example, frozen ready meals, cans, and staples such as rice and pasta) or prepare your own dishes to freeze and reheat during your recovery.

Clean up – Before going into hospital, have a good long bath or shower, cut your nails (don’t forget to take off any nail polish) and wash your hair. Put on freshly washed clothes. This helps prevent unwanted bacteria coming into hospital, which can increase your risk of developing complications.


Pre-admission assessment

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

At this clinic, you will 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 will 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 any concerns at any time.

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

whether you are taking any tablets or other types of medication – it helps if you bring details with you of anything you are 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 are allergic to anything

You will be advised to stop smoking if you smoke. This is because smoking increases your chances of a serious chest infection and slows down the time your wounds will take to heal. Smoking can also increase your risk of 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 temporarily swell after the operation)

something comfortable and easy to wear during the day


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 concerning 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.

Although you will have a bedside locker for your personal belongings, it's a good idea to avoid taking any unnecessary valuables into hospital.


What happens during coronary artery bypass surgery 

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.

Because the procedure is performed using a general anaesthetic (where you are asleep during the operation), you must not eat or drink for at least six hours before the operation. You may be able to have occasional sips of water until two hours before the operation.


During the operation

CABG surgery usually lasts three to six 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 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 three or four vessels grafted. If you need two, three or four 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 does not 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 sternum 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 CABG procedure.

A CABG is often described as on-pump surgery as 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 the OPCAB, your heart is still beating while the new blood vessel grafts are attached and a heart-lung bypass machine is not used.

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

The benefits of an OPCAB are:

it often takes less time to perform than a CABG

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 is usually shorter

The main disadvantage is that OPCAB is more technically demanding, as the grafted vessels have to be delicately connected while the heart is beating. This means that OPCAB 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.


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 known as an endoscope is then inserted into the incision. An endoscope is a thin, long flexible tube that contains a light source and a video camera, so that images of the inside of your body can be relayed to an external monitor (screen).

The endoscope allows the surgeon to locate your saphenous vein. Surgical instruments can then 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 is likely to be less scarring and your leg will usually heal more quickly 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.


Totally endoscopic robotically assisted coronary artery bypass (TECAB) grafting

Another new technique in heart surgery is totally endoscopic robotically assisted coronary artery bypass (TECAB) grafting, which is a minimally invasive (keyhole) way 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'.

With this type of surgery there are lower rates of wound infection, minimal scarring and a faster recovery time. However, as this is a new technique that has only been carried out on a small number of people, it is 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 are considering having a totally endoscopic robotically assisted CABG, it is important you understand that there are still uncertainties about how safe the procedure is and how well it works.

Heart bypass illustration

1. bypass
2. aorta
3. coronary artery
4. vena cava
5. auricle


Recovering from coronary artery bypass surgery  

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

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 will feel some discomfort and grogginess after the procedure, but you will be given painkillers to help relieve any pain. You should tell your doctor or nurse if the pain increases or if you notice any excessive bleeding.

Recovery from a CABG procedure takes time and everyone recovers at slightly different speeds. Generally, you should be able to sit in a chair after one day, walk after three days and walk up and down stairs after five or six days.

Most people make a full recovery within 12 weeks of the operation. However, if you experience complications during or after the 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 press on your wounds can also help.

For the first three to six weeks, you will probably feel tired a lot of the time. This is because your body is using a lot of energy to heal itself. By six weeks, you should be able to do most normal activities and by three months, you are 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 the skin heals.

While you are recovering in hospital, you will 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 are healing.

You will 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 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 six 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.

How long you need off work varies from person to person. If you are recovering well and your job is not physically strenuous, you can usually go back to work in about six to eight weeks. However, you will normally need more time off if you experience any complications or your job involves a lot of standing and lifting.

While you are 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:

a loss of appetite


swelling or pins and needles where the blood vessel graft was removed

muscle or back pain

tiredness and difficulty sleeping

feeling upset and having mood swings

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

Side effects tend to disappear within four to six weeks after 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 support groups.


When to seek medical advice

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

severe or increasing pain in or around the wound

extreme shortness of breath

swelling around the wound

any pus coming from the wound

a high temperature (fever)

palpitations that make you feel dizzy or faint

excessive sweating

If you cannot contact your GP, 


Cardiac rehabilitation

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

While you are in hospital before and after your operation, a member of the cardiac rehabilitation team may speak to you about this. You may be invited to join a cardiac rehabilitation programme starting a few weeks after you leave hospital.

What happens in cardiac rehabilitation programmes can vary widely throughout the country, but most will cover areas such as exercise, education, relaxation and emotional support.


Life after a coronary artery bypass graft

When you have fully recovered from your operation, it is important to adopt a healthy lifestyle to reduce your risk of developing further heart problems in the future. This includes:

stopping smoking if you smoke

eating a healthy diet

losing weight if you are overweight or obese

moderating your alcohol intake

exercising regularly

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

Risks of surgery 

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

Some of the main complications associated with a CABG are described below.


Irregular heartbeat

Up to one in every three people who have a CABG will develop a problem called atrial fibrillation. This is a condition that causes an irregular and often abnormally fast heart rate.

However, this is not usually serious and can normally be treated easily with a course of medication.



There is 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 CABG. This is estimated to occur in up to one in every 25 people who have the procedure.

There is also a smaller chance of more serious infections affecting the lungs or inside of the chest after a CABG.

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


Reduced kidney function

Less than one in every 20 people who have a CABG 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.


Problems affecting the brain

Up to one in every 20 people experience some problems with their memory after a CABG 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 is also a risk of serious problems affecting the brain during or after a CABG, such as a stroke. It's estimated that around one in every 50 people who has a CABG will experience a stroke, which can leave you with permanent movement, speaking and swallowing problems and can be fatal in some cases.


Heart attacks

Both the heart and the coronary arteries that supply the heart with blood are in a vulnerable state after surgery, especially in the first 30 days after a CABG.

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


Who's most at risk?

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 is thought that this may lead to a higher risk of experiencing complications because they are generally older at the time of surgery.

Having emergency surgery to treat a heart attack – Emergency surgery is always riskier as there is less time to plan the surgery, and the heart can be seriously damaged from the heart attack.

Having three or more vessels grafted – The more complex the operation, the greater the chance that complications will occur.

Being obese – If you are 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 your specific risk before surgery takes place.


Life after a coronary artery bypass 

A coronary artery bypass graft (CABG) is not 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 the risk of heart problems in the future.


Healthy lifestyle

There are a number of lifestyle changes you can make after having a CABG 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 CABG. To reduce this risk, you should try to eat a diet that 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)


cakes and biscuits

Instead, you should try to eat foods such as:

wholegrain rice, bread and pasta

fruit and vegetables – ideally five portions a day

oily fish, such as mackerel and sardines

You should also try to cut down on the amount of salt you add to your food and make sure you 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 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 is strenuous enough to leave you slightly breathless.

Examples of moderate-intensity aerobic activities include:

walking fast

riding a bike on level ground or with few hills

doubles tennis

pushing a lawn mower


If you find it difficult to achieve 150 minutes of activity a week, start at a level that 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 begins to improve.


Lose weight

If you are overweight or obese, you can reduce your risk of further heart problems by trying to reach a healthy weight. Find out if you need to lose weight with the BMI healthy weight calculator.

The best way to lose weight is to follow a healthy diet and exercise regularly (see above). You may find it helpful to follow a structured weight loss plan, 


Stop smoking

Smoking can significantly increase your risk of heart problems because it causes your arteries to narrow and raises your blood pressure.

If you want to stop smoking,  which will provide you with dedicated help and advice about the best ways to give up smoking.123 1044. The specially trained helpline staff will offer you free expert advice and encouragement.

If you are committed to giving up smoking but do not want to be referred to a stop smoking service, your GP should be able to prescribe medical treatment to help with withdrawal symptoms you may experience after giving up.


Moderate your alcohol consumption

If you drink alcohol, do not exceed the recommended daily limits of three to four units for men and two to three units for women. A unit of alcohol is roughly half a pint of normal-strength lager, half a standard glass of wine or a single measure (25ml) of spirits.

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


Taking medication

Although you will probably need to take less medication after having a CABG, it is likely you will 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:

low-dose aspirin



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

If you are prescribed one of these medications after your operation, it is 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 CABG, you may also be prescribed some other medications, such as beta-blockers and angiotensin-converting enzyme (ACE) inhibitors. 


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Alternatives to a coronary artery bypass 

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 your 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 then 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.

Serious complications of a coronary angioplasty are uncommon, but heart attacks, strokes and deaths are estimated to occur in less than one in every 100 cases.

A coronary angioplasty may not 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 CABG, 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 will recover from the effects of the operation quicker than you will from a CABG. Coronary angioplasty usually has a smaller risk of complications, but there is a chance you will 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.

CABG has a longer recovery time than coronary angioplasty and a higher risk of complications. However, only one person in 10 who has a CABG requires further treatment. Also, some evidence suggests that CABG is usually a more effective treatment option for people who are 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 is possible to treat coronary heart disease with a number of different medications, such as:

antiplatelets – to help prevent your blood from clotting and reduce your risk of problems such as heart attacks

statins – to help reduce high cholesterol

beta-blockers and nitrates – to help prevent angina and treat high blood pressure

These medications can help control some of the symptoms of heart disease and can reduce the risk of the condition getting worse, but a CABG may be recommended if the condition is severe or there is a particularly high risk of serious problems (such as heart attacks) because it is a more effective treatment in these cases.