The aim of a coronary artery bypass is to restore blood flow to the heart msucle. The surgery does not remove the blockages but provides a ‘detour' around the blockage – a bypass.

What is involved?

A blood vessel from the leg, the arm or inside the chest can be used as a bypass graft. The surgeon will decide which to use at the time of the operation.

When a suitable graft has been found, one end of it is sewn onto the aorta (the main artery coming out of the heart), or another major artery within the chest.

The other end is sewn onto the coronary artery below the blockage. This results in a better blood supply to the heart muscle.

The procedure will vary from patient to patient. Your doctor can explain it to you and answer any questions.

The procedure

At the start of the operation the surgeon makes a cut along the middle of your breastbone, in order to reach your heart. This is called a sternotomy.

The bypass operation can then be done in one of two ways:

Heart–lung machine

You are connected to a heart–lung machine, which maintains the blood flow to your body during the procedure. Your body temperature is lowered to protect vital organs such as the brain and kidneys. A special fluid then stops the heart while the coronary artery grafting is done.

The heart is not taken out of the chest for the operation. When the grafts are complete, you are warmed back to normal temperature. The heart starts beating again, and the heart-lung machine is removed.

Off-pump surgery

The other way to do the operation is without using the heart-lung machine. The heart is operated on while it is still beating. This is called ‘off-pump' or ‘beating-heart' surgery.

The coronary arteries are held still, one at a time, using a stabilising device. The grafting is then performed in exactly the same way as before, except that your body is kept warm.

After surgery

Regardless of which method is used, at the end of the operation the breastbone is closed with stainless steel wires, and you are taken to intensive care. When you arrive there, your skin may feel cool to the touch because some heat is lost during transport.

This information was first published in You and Your Heart Surgery - an education booklet for patients, families and friends. © 2002 Northern Sydney Central Coast Area Health Service