Coronary Artery Bypass Grafting: Explained
Coronary artery disease is a condition in which plaque builds up within the blood vessels that supply the heart with oxygen-rich blood. As plaque accumulates, the coronary arteries narrow or become blocked, which can cause chest pain, heart attack, and, over time, heart failure.
If medical therapy or stents are not sufficient at managing coronary artery disease, a surgical procedure called coronary artery bypass grafting (CABG) may be recommended. With CABG (pronounced “cabbage”), surgeons take healthy blood vessels from elsewhere in the body and use it to make a graft that reroutes blood around the narrowed or blocked sections of the coronary arteries to restore blood flow to the heart. One end of the graft is sewn to the aorta (the largest artery) and the other end to the affected coronary artery.
Traditionally, CABG is done using a heart-lung bypass machine, which takes over the functions of the heart and lungs by circulating oxygen-rich blood throughout the body as the surgery takes place. Although the procedure, sometimes called “on-pump” CABG, is safe and effective, the use of the heart-lung bypass machine can, in some cases, cause inflammation throughout the body, resulting in problems with the functioning of multiple organs.
Another option is something called anaortic bypass, or “off-pump” CABG, in which the heart-lung bypass machine is not needed.
“We [instead] use specific instruments to stabilize a portion of the heart the bypass is targeting, and we let the heart and the lungs function normally for the entire operation,” says Fabio Ramponi, MD, a Yale Medicine cardiac surgeon. “And there is a very strong advantage. The patient essentially has much less of an inflammatory process to fight during the recovery.”
The other advantage of using advanced coronary surgery techniques is to use more arterial conduits, he adds. “Our blood vessels are categorized into arteries and veins. Arteries are exposed to high pressure, while veins are usually exposed to very low pressure. If we use a vein to deliver blood to the heart, over time, this high-pressure stress on the wall of the vein will essentially build up and they will block off,” Dr. Ramponi says. “There is a very large body of evidence that shows that the more arterial grafts you use, the better the benefit for the patient in the long run, not only in terms of reducing the risk of more chest pain or a heart attack or having to have another procedure done but also a survival benefit.”
At Yale, we embrace this culture of offering the best therapy for our patients, says Dr. Ramponi. “The anaortic off-pump approach offers the short-term benefit of avoiding a stroke and the long-term benefit of using arterial grafts so that the patient doesn't have to come back for another operation,” he says. “The aim is to fix coronary artery disease once and forever, with one operation.”
In the video above, Dr. Ramponi talks more about CABG.
