A coronary artery bypass graft (CABG) is a procedure that diverts blood around narrowed or clogged parts of the major arteries (blood vessels), to improve blood flow and oxygen supply to the heart.
It may be necessary in the following situations:
- There is severe hardening and narrowing of the coronary arteries.
- Many coronary blood vessels are blocked.
- You are at risk of having a life-threatening heart attack.
- Your blood supply needs restoring after a heart attack.
- You need emergency treatment for ventricular arrhythmia.
These are discussed in more detail below.
Coronary arteries are severely affected
Your arteries harden and narrow naturally as you get older, but this process can be dangerously accelerated by:
When the coronary arteries become so narrow that blood supply to the heart is reduced, it is known as coronary heart disease.
If tests show that many branches of the coronary arteries are blocked, or the levels of hardening and narrowing are severe, then a CABG may be required.
If hardened or narrowed coronary arteries are not treated, you may experience a pain in your chest known as angina. Angina happens because blood flow to your heart is reduced.
Preventing a life-threatening heart attack
A CABG may also be recommended if you are thought to be at risk of a serious heart attack. You are thought to have such a risk if tests have found there is a particularly high level of narrowing in a section of your coronary artery called the left anterior descending artery (LAD). This is because heart attacks that are triggered by a blood clot blocking the LAD are extremely serious. If they are not treated within five minutes of symptoms starting, they are usually fatal.
Restoring blood supply after a heart attack
A CABG may also be used to help restore blood supply to your heart after a heart attack.
A coronary angioplasty is usually the preferred surgical option for treating heart attacks, but a CABG may be required if:
- The coronary angioplasty fails to restore the blood supply to your heart.
- It is not possible to perform angioplasty for technical reasons, for example, because many of the blood vessels are blocked.
