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.
You'll have the operation under general anaesthetic. This means you'll be asleep. You must not eat or drink for at least 6 hours before the operation.
You may be able to have occasional sips of water up to 2 hours before 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 grafted.
The procedure
Blood vessels can be taken from your leg, inside your chest or your arm. Other blood vessels in these areas will compensate for the loss of these blood vessels.
The number of blood vessels used will depend on how severe your coronary heart disease is. It will also depend on how many of the coronary blood vessels have become narrowed.
Most people will need 3 or 4 vessels bypassed. 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 bypass graft vessels is usually your internal mammary artery. Surgeons prefer to use this vessel. This is because it does not narrow over time, unlike the blood vessels taken from your leg or arm.
After your surgeon removes all the graft vessels, they will make a cut (incision) down the middle of your chest. This is done 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. You'll be given medicine to stop your heart while your surgeon attaches the new grafts. The grafts will divert the blood supply around the blocked artery.
After the grafts have been attached, your surgeon will use controlled electrical shocks to start your heart again. They will fix your breastbone together using permanent metal wires. They will sew the skin on your chest using dissolvable stitches.
Endoscopic saphenous vein harvesting (ESVH)
Endoscopic saphenous vein harvesting (ESVH) is a way of removing the veins from your legs. Instead of making a large incision in your leg, the surgeon makes some small incisions near your knee. This is known as 'keyhole' surgery.
A special device called an endoscope will be inserted into the incision. An endoscope is a thin, long flexible tube with a light source and video camera at one end. Using this camera, images of the inside of your body can be sent to an external television monitor.
Your surgeon can use an endoscope to locate your saphenous vein. They can pass surgical instruments through the endoscope to remove a section of the vein. Nearby tissue is then sterilised with antibiotic fluid and the incision is healed.
Advantages of this technique are that there is less scarring and your leg should heal quicker. There are uncertainties about how well the grafts work in the years after the procedure.
Content supplied by the NHS and adapted for Ireland by the HSE
