A coronary bypass is a venous graft which bypasses a clogged section of one of the coronary arteries to supply the heart with oxygenated blood. The process of creating the graft is known as a coronary bypass surgery, and it is a major surgery, performed by a cardiovascular surgeon. This surgery is recommended to patients when treatments for angina appear to be ineffective, or when there are other signs that a clogged coronary artery is posing a health risk.
In the coronary bypass surgery, the surgeon identifies the artery or arteries which are clogged, and harvests veins from elsewhere in the patient's body, such as the leg. These veins are sewn to create a bridge between the aorta and an area of the clogged artery which is below the blockage, so that oxygenated blood can reach the heart. The surgeon may perform multiple bypasses in one procedure, if it is deemed necessary, so people may use terms like “triple bypass” or “quadruple bypass,” referring to the number of coronary arteries bypassed during the procedure.
The bypass surgery can take four to six hours, and sometimes longer, depending on the patient. During the surgery, the patient is kept under general anesthesia, and put on a heart-lung machine to do the work of the heart. This allows the surgeon to operate on a still heart, which is easier and safer than trying to perform surgery on a beating heart. The surgical team includes the heart surgeon, the technician to run the heart-lung machine, the anesthesiologist, and support staff which can include other doctors as well as surgical nurses.
People must stay in the hospital for up to a week after coronary bypass so that their progress can be monitored. Once released, the patient's activities are restricted for several weeks during the healing process. Because a coronary bypass requires that the sternum be cracked, the patient needs to be careful about reopening the incision, as this could be dangerous. After surgery the patient is not allowed to lift heavy objects, to reach above the head, or to engage in strenuous activity until the sternum has healed.
Coronary bypass surgery is usually scheduled, giving patient and surgeon time to prepare, although sometimes it can be undertaken on an emergency basis. Before the surgery, the patient will be evaluated to check for any risks which could make the procedure more dangerous, and the patient will also be familiarized with the restrictions associated with recovery.