Coronary artery bypass graft surgery is a type of operation carried out to treat disease of the coronary arteries, which supply the heart muscle with blood. A disease known as atherosclerosis can cause fatty deposits to collect inside arteries, leading to narrowing and, eventually, obstruction. When the coronary arteries become obstructed, this can lead to loss of blood supply to the heart, causing conditions such as angina and heart attacks. Coronary artery bypass graft surgery involves taking pieces of blood vessels, known as grafts, from other parts of the body and rerouting blood through them, bypassing the blocked coronary artery.
Preparing for a coronary artery bypass graft operation generally involves having a medical check, where tests may be carried out and information collected regarding a patient's current medication, previous experience with anesthetics, allergies, and the condition of the teeth. The teeth are inspected and treated, if necessary, because bacteria from the mouth could potentially infect the heart. It is advisable to give up smoking, because it can delay healing and could increase the risk of blood clots and chest infections following coronary artery bypass graft surgery.
During surgery, blood is diverted to a machine used to carry out the work of the lungs and heart, so the heart can be stopped. Different types of grafts may be taken from blood vessels in the chest, arms or legs. An average of around four coronary arteries may need to be bypassed in each operation.
The heart is accessed by cutting through the breastbone, and each coronary artery bypass graft is sewn into place. After the last graft has been attached, electric shocks are used to restart the heart. In an alternative technique, known as OPCAB, or off-pump coronary artery bypass, surgery is carried out by keeping the heart beating, removing the need for blood to be diverted to a heart-lung machine.
After coronary artery bypass graft surgery, it is usually necessary to spend some time being monitored in an intensive care unit. Painkilling drugs are given to relieve discomfort, and recovery is a gradual process. It may be several days before it is possible to get up and walk around, and a complete recovery generally takes about 12 weeks. The outlook following surgery is most often positive. Around three quarters of patients remain free from heart symptoms for five years after their graft surgery.
