Coronary artery disease is a condition in which the arteries that supply blood and oxygen to the heart become narrowed and hardened. Typically, this condition is caused by the build up of plaque and fat on artery walls, which narrows the vessels that connect to the heart. This narrowing of the arteries restricts blood from reaching the heart, and proper circulation of blood and oxygen is not provided to the heart and its surrounding tissue. Blood clots can also form and completely block the artery. Coronary artery disease develops gradually and can eventually lead to a heart attack or heart failure.
Coronary artery disease is often initially treated with medication, and in some cases, angioplasty and stenting are performed. For many types of blockages however, coronary bypass surgery is the best option for treatment. The coronary artery bypass procedure creates new pathways for oxygen-rich blood to flow into the heart and bypass the blocked arteries. During the coronary artery bypass procedure, one or more blocked coronary arteries are bypassed using a blood vessel grafted from another part of the body, restoring normal blood flow to the heart. The blood vessel grafts come from the patient‘s own arteries and veins in either the chest, leg, or arm.
The Coronary Artery Bypass Procedure
General anesthesia is administered to the patient during coronary bypass surgery. The surgery can be performed "on-pump" with the use of a heart-lung bypass machine or as an "off-pump" procedure also known as "beating heart" surgery. The type of method that is used depends upon the patient‘s age, health and an evaluation of the patient‘s heart and arteries.
During surgery the sternum is divided and the heart is temporally stopped. Based on the prior evaluation, the patient‘s vital functions may become fully supported by a cardiopulmonary bypass pump which takes over the function of the heart and lungs, blood circulation and oxygen content of the body. Healthy blood vessels are taken, often from inside the chest wall or from the lower leg, and attached to the the ends above and below the blocked artery so that blood flow is diverted, or bypassed around the narrowed portion of the clogged artery. The coronary artery bypass procedure generally takes about 3-5 hours to perform, depending on the number of arteries that are being bypassed. On average, two to four coronary arteries are repaired during this procedure.
A minimally invasive form of coronary artery bypass surgery may also be performed. In this procedure, the coronary bypass is performed through a smaller incision in the chest, often with the assistance of robotics and video imaging that help the surgeon operate in a small area.
Recovery from Coronary Artery Bypass Surgery
After coronary artery bypass surgery, most patients spend 1 to 2 days in the cardiac intensive care unit for monitoring. Monitoring includes continuous heart function, blood pressure and oxygen monitoring and frequent vital sign checks. Overall, the patient is hospitalized for about 1 week. Medications such as statins and cholesterol-lowering medicine are often prescribed after surgery. Most patients will take part in a cardiac rehabilitation program as a part of their recovery. Most people can return to work within 4 to 6 weeks and full recovery usually takes about 10 weeks.
Risks of Coronary Artery Bypass Surgery
As with any invasive procedure there are risks associated with coronary artery bypass surgery. Risks include:
- Bleeding
- Infection
- Heart arrhythmias
- Heart attack
- Stroke
The risk of developing these complications depends on the overall health of the patent prior to surgery. Any concerns should be discussed with a doctor prior to undergoing surgery.
Although bypass surgery improves blood supply to the heart, it does not cure underlying coronary artery disease. Medication and healthy lifestyle changes are strongly recommended to reduce the risk of recurring heart disease, and the need for additional heart surgery in the future.