1.    Surgery for the symptoms of angina

2.    Surgery to increase life expectancy

Most, but not all patients undergoing coronary artery surgery are suffering with angina, which usually manifests itself as chest pain or discomfort in the jaw or arm on exertion. In many patients angina can be treated with appropriate medications, but if symptoms persist they can often be treated by coronary artery bypass surgery. Certain subgroups of patients with angina will also have an increased life expectancy after surgery, compared with patients left on medical or other treatments. This is because the small risk associated with undergoing coronary artery surgery is more than compensated for by a decreased incidence of myocardial infarction with its associated complications after successful surgery. Occasionally it is appropriate to offer surgery to patients with few or no symptoms because of the associated potential benefits on survival.

Techniques of operation

The aim of coronary artery surgery is to increase the blood flow to heart muscle by bypassing the narrowings in the coronary arteries. In the same way that a road through a village may be bypassed by a dual carriageway around the outside, the heart bypass increases flow around the problem area, but the native coronary artery with its associated narrowing is left in place once the bypass is completed. The key to successful coronary artery surgery is to manufacture sufficient satisfactory bypasses whilst minimising  the complications which can be associated with surgery.