Cardiac Center
MRK-D-20-2012
Coronary Artery Bypass Graft
What is Coronary Artery bypass surgery? Coronary bypass surgery is a procedure that restores blood flow to your heart muscle by diverting the flow of blood around a section of a blocked artery in your heart. Coronary bypass surgery uses a healthy blood vessel taken from your leg, arm, chest or abdomen and connects it to the other arteries in your heart so that blood is bypassed around the diseased or blocked area. After a coronary bypass surgery, normal blood flow is restored. Coronary bypass surgery is just one option to treat heart disease. Coronary bypass surgery can help reduce your risk of having a heart attack. For many people who have coronary bypass surgery, symptoms such as chest pain and shortness of breath are reduced after having the surgery. Coronary bypass surgery is an option if: • You have severe chest pain caused by narrowing of several of the arteries that supply your heart muscle, leaving the muscle short of blood during even light exercise or at rest. • You have more than one diseased coronary artery and the heart’s main pump — the left ventricle — is not functioning well. • Your left main coronary artery is severely narrowed or blocked. This artery supplies most of the blood to the left ventricle. • You have an artery blockage for which angioplasty isn’t appropriate, you’ve had a previous angioplasty or stent placement that hasn’t been successful, or you’ve had stent placement but the artery has narrowed again (restenosis).
Risks: • •
Bleeding. Heart rhythm irregularities (arrhythmias).
Less common complications include: • Heart attack, if a blood clot breaks loose soon after surgery. • Kidney failure. • Infections of the chest wound. • Memory loss or troubles with thinking clearly, or it might be a Stroke. How you prepare: To prepare for coronary bypass surgery, your doctor will give you specific instructions about any activity restrictions and changes in your diet or medications you should follow before surgery. You’ll need several presurgical tests, often including chest X-rays, blood tests, an electrocardiogram and a coronary angiogram. What you can expect: During the procedure: Coronary bypass surgery generally takes between three and six hours and requires general anesthesia. On average, surgeons repair two to four coronary arteries. The number of bypasses required depends on the location and severity of blockages in your heart. Graft Preparation • Internal mammary arteries: These arteries can be kept intact at their origin because they have their own oxygen-rich blood supply, and then sewn to the coronary artery below the site of the blockage. If the surgeon removes the mammary artery from its origin, it is called a “free” mammary artery. • The radial (arm) artery is another common type of arterial graft. There are two arteries in the arm, the ulnar and radial arteries. Most people receive blood to their arm from the ulnar artery and will not have any side effects if the radial artery is used. Careful preoperative and intraoperative tests determine if the radial artery can be used. If the radial artery is used as the graft, the patient may be required to take a calcium channel blocker medication for several months after surgery. This medication helps keep the artery open. Some people report numbness in the wrist after surgery. • Saphenous veins can be used as bypass grafts. Minimally invasive saphenous vein removal does not require a long incision. One to two incisions are made at the knee and a small incision is made at the groin. This results in less scarring and a faster recovery. • The gastroepiploic artery to the stomach and the inferior epigastric artery to the abdominal wall are less commonly used for grafting. To bypass the blockage, the surgeon makes a small opening just below the blockage in the diseased coronary artery. If a saphenous (leg) or radial
(arm) vein is used, one end is connected to the coronary artery and the other to the aorta. If a mammary artery is used, one end is connected to the coronary artery while the other remains attached to the aorta. The graft is sewn into the opening, redirecting the blood flow around this blockage. The procedure is repeated until all affected coronary arteries are treated. It is common for three or four coronary arteries to be bypassed during surgery. Before the patient leaves the hospital, the doctor or nurse will explain the specific bypass procedure that was performed. Heart-Lung Machine During surgery, the heart-lung bypass machine (called “onpump” surgery) is used to take over for the heart and lungs, allowing the circulation of blood throughout the rest of the body. The heart’s beating is stopped so the surgeon can perform the bypass procedure on a “still” heart. Off-pump or beating heart bypass surgery allows surgeons to perform surgery on the heart while it is still beating. The heart-lung machine is not used. The surgeon uses advanced operating equipment to stabilize (hold) portions of the heart and bypass the blocked artery in a highly controlled operative environment. Meanwhile, the rest of the heart keeps pumping and circulating blood to the body. Minimally Invasive Technique Minimally invasive coronary artery bypass (MIDCAB) surgery is an