Coronary Bypass

Written by: 
Dr Roger Henderson

A coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft (CABG) is a surgical procedure used to divert bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. around blocked or narrowed arteries in the heart. The procedure has the effect of improving bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. flow and oxygen supply to the heart and so reducing symptoms of ischaemic heart disease such as anginaA central chest pain caused by insufficient oxygen supply to the heart..

Each year more than 800,000 people worldwide have a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft. The majority of these are men over the age of 60.[1] It is usually a successful operation in that the long-term benefits are good, with most people remaining free of heart-related symptoms for at least five years and many for ten years.

For people who may need the procedure the main questions are:

When are coronary artery bypass grafts needed?

Coronary arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass grafts are performed:

  • To treat coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. disease when medication and changes in lifestyle have not improved symptoms
  • To help reduce the risk of a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction..

They are recommended:

  • In cases of severe anginaA central chest pain caused by insufficient oxygen supply to the heart.
  • If there is more than one diseased coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood.
  • If the main coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. is blocked
  • If the main pumping chamber of the heart (the left ventricleEither of the two lower chambers of the heart, or any of the four cavities within the brain.) is not working properly
  • After an initial heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. to prevent a repeat.

The operation does not provide a permanent cure, however, because over time the coronaryRelating to the arteries supplying the heart itself. arteries can become clogged up again and so the procedure may need to be repeated.

How is a coronary artery bypass graft performed?

A coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft operation is performed under a general anaestheticAny agent that reduces or abolishes sensation, affecting the whole body..

It takes between 2 and 5 hours, depending on the complexity of the surgery and how many arteries in the heart are being bypassed.

To start with, your surgeon will take a healthy bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. vessel from your leg, chest or arm before accessing the heart by cutting open the chest through the breastbone.

During the operation it is usual for bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. to be re-routed to a heart-lung bypass machine, which takes over the work normally done by your heart and lungs and pumps bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. and oxygen through the body while the heart is temporarily stopped. This allows the surgeon to attach the new grafts from the healthy vessels to the heart to bypass the diseased segments of the coronaryRelating to the arteries supplying the heart itself. arteries. 

Once the grafts are in place and secure, the heart is restarted using electric shocks and the breastbone is then stitched up using wire clips.

Some surgeons are now using a technique known as off-pump coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass surgery, in which the heart continues to beat as the new bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. vessels are attached.

This has the benefit of taking less time than a conventional coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft operation, reduces the length of hospital stay and carries less risk of post-operative complications.

Another option, available in some cases, is to have a minimally invasive coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft. The operation is performed with precision instruments through small incisions, and so does not require the cutting open of the chest. It is performed under general anaestheticAny agent that reduces or abolishes sensation, affecting the whole body..

What are the possible complications after a coronary artery bypass graft?

Possible complications after a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft include: 

  • Infection
  • Reaction to the anaestheticA medication that reduces sensation.
  • Having a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction.
  • Having an abnormal heart beat
  • Having a stroke
  • Bleeding (either during or after the operation).

These risks are increased if you are already suffering from kidney disease, diabetes, chronicA disease of long duration generally involving slow changes. lung disease such as emphysema or if you have peripheral vascular disease where other bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. vessels in the body are narrowed or blocked.

Percutaneous transluminal coronary angioplasty (PTCA) 

If your surgeon feels the risks of a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft procedure are too great, he or she may suggest an alternative treatment known as a percutaneous transluminal coronaryRelating to the arteries supplying the heart itself. angioplastyThe mechanical widening or clearing of a narrowed or obstructed blood vessel, performed during angiography, which is used to help with visibility., also sometimes called percutaneous intervention (PCIAbbreviation for percutaneous coronary intervention, or angioplasty: the mechanical widening or clearing of a narrowed or obstructed blood vessel.) or just angioplastyThe mechanical widening or clearing of a narrowed or obstructed blood vessel, performed during angiography, which is used to help with visibility..

In this procedure, any material that is blocking the bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. vessels is flattened out so that bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. can flow through them more easily once more.

A percutaneous transluminal coronaryRelating to the arteries supplying the heart itself. angioplastyThe mechanical widening or clearing of a narrowed or obstructed blood vessel, performed during angiography, which is used to help with visibility. has a number of benefits:

  • It is much less risky than a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft
  • It is performed under local anaestheticA medication that reduces sensation in a part of the body., whereas a standard coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft requires general anaestheticAny agent that reduces or abolishes sensation, affecting the whole body.
  • It usually involves one day only in hospital and has a quicker recovery time than a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft
  • It also is preferred in people with milder heart disease who may not warrant a full coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft.

Studies have found that, compared with people who have undergone a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft, those who have had a percutaneous transluminal coronaryRelating to the arteries supplying the heart itself. angioplastyThe mechanical widening or clearing of a narrowed or obstructed blood vessel, performed during angiography, which is used to help with visibility. are

  • No more likely to have a further heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. or to die in the three years after the procedure
  • Are more likely to require a repeat procedure.[2]

What happens after a coronary artery bypass graft?

Following a standard, open coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft, patients are closely monitored in an intensive care unit for up to 24 hours before being moved to a high-dependency bed where the working of the heart and lungs can be closely monitored.

Most patients are able to leave hospital within 5 to 7 days of surgery, provided there are no complications such as infectionInvasion by organisms that may be harmful, for example bacteria or parasites. or bleeding.

Pain or discomfort from the surgery, including any leg discomfort if a vein was taken from the leg, can be treated with simple painkillers.

Most discomfort has settled after 6 weeks and a full recovery should be expected after 12 weeks.

It is quite normal to feel tired or short of breath after a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft, and rest is important in the early stages of recovery. You may also feel rather low in mood but this will gradually lift as your recovery continues.

Getting back to normal

Many people are able to go back to work 6 weeks after surgery, although if you have a manual job this may take a little longer.

You can resume having sex after 6 weeks and start low-impact sports after 12 weeks.

In many countries you will be required to inform driver-licensing authorities that you have had a coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft.

Is a coronary artery bypass graft associated with memory loss? 

A few people report that their memory seemed to be affected following coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. bypass graft surgery, but this is uncommon and is usually back to normal a year afterwards.

Staying healthy 

To help reduce the chances of needing further heart surgery in the future, you will probably be recommended to:

  • Stop smoking. This is the single most important thing you can do to help improve your health overall
  • Maintain a healthy body weight and try to lose weight if you are overweight
  • Control your bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. pressure
  • Keep a tight control on your bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. sugar levels if you have diabetes
  • Exercise daily
  • Eat a healthy diet low in saturated fatOne of the three main food constituents (with carbohydrate and protein), and the main form in which energy is stored in the body. and rich in fresh fruit and vegetables

It is also worth asking your doctor about cardiac rehabilitationA staged programme of exercise and lifestyle changes to help recovery from a heart attack and help to prevent a repeat heart attack. , a programme including exercise, health education and help with reducing stressRelating to injury or concern., supervised by medical professionals.
 

References: 

1. Severe morbidity after coronaryRelating to the arteries supplying the heart itself. arteryA blood vessel that carries blood away from the heart. Apart from the pulmonary artery and umbilical artery, all arteries carry oxygenated blood. surgery. Pepper J. Curr Opin Cardiol 2000;15:400–5.

2. S J McPhee, MA Papadakis and LM Tierney. Current Medical Diagnosis and Treatment 2008. McGraw Hill Medical Books, 2007.