Coronary Artery Disease and Heart Bypass Surgery
According to the U.S. Department of Health and Human Services about 14 million Americans are affected with Coronary Artery Disease (CAD). This disease is the leading cause of death for both men and women in the United States. Yet, over the past 20 years, modern medicine has greatly improved the life expectancy for people with heart disease.
One of the reasons for this is a specific surgical procedure called coronary artery bypass surgery. It’s also called CABG, with the “G” standing for graft. That means taking a blood vessel from another part of the body to bypass the diseased heart artery.
The purpose of this hub is to provide an overview of CAD and CABG. It is not intended as medical advice.
Healthy Coronary Arteries
The heart, like the rest of your body, needs oxygen to function. Blood carries oxygen to your heart through blood vessels called arteries. The specific arteries that supply blood and oxygen to your heart are called coronary arteries. Coronary arteries run across the surface of the heart, supplying it with blood rich in oxygen.
The artery on the right supplies blood to the right side and the bottom of the heart.
The artery on the left separates into two branches. One supplies blood to the back, left side, and bottom of the heart. The other branch supplies blood to the front and left side of the heart.
When things are working well, these arteries, with their smooth, interior flexible walls can increase the amount of blood flow provided when you need it. For example, when you are exercising or taking a steam shower. (See my other hub Steam Shower vs. Sauna. What’s the Difference? )
Coronary Artery Disease (CAD)
CAD begins with damage to the inner lining of a coronary artery. One of the primary causes is the build up of plaque in the layers of the artery wall. Plaque is made up of cholesterol and other particles found in the blood.
When plaque builds up in the arteries, the interior walls of the artery get narrower. This results in less blood getting through to your heart. At some point, if the plaque continues narrowing the artery, you can get angina, or chest pain.
If the plaque ruptures it can cut off blood flow in the artery entirely. The result is a part of the heart not receiving enough oxygen. This can result in a heart attack.
Even if plaque doesn’t rupture, CAD makes the heart work harder to get oxygen. Over time, this can weaken the heart and lead to heart failure.
Coronary Artery Bypass Surgery (CABG)
One of the options for CAD is to bypass the blocked parts of a coronary artery. This is done by creating a new pathway that goes around the blockage. This is what is referred to as coronary artery bypass surgery, or CABG.
The idea is to take a healthy vein or artery from another part of your body and graft, or connect it to the existing artery before and after the blocked part of the artery. Blood then flows through this graft, bypassing the blockage.
Healthy veins can be taken from your leg, your arm, or an internal artery located in the chest wall.
Depending on how many coronary arteries are bypassed during the surgery, there are four possible surgical alternatives:
- Single bypass (one artery is bypassed)
- Double bypass (two arteries are bypassed)
- Triple bypass (three arteries are bypassed)
- Quadruple bypass (four arteries are bypassed)
To reach the heart for this surgery, a heart surgeon must cut open the breastbone, which is then left open for the remainder of the surgery. Sometimes the heart must be stopped while the graft is attached. In this case, called an “on-pump” procedure, the patient’s blood is circulated through a heart-lung machine. The machine supplies oxygen to the blood which is then pumped back through the body.
A surgical procedure in which the heart does not have to be stopped is known as an “off-pump” procedure.
When the blood is again flowing through the attached grafts, the patient’s breastbone is then rejoined with wires. The wire will stay in the patient’s chest permanently.
Over half a million CABG surgeries are done every year. After a hospital stay of from 3 to 7 days, the patient usually goes home. Home recovery is typically 4 to 8 weeks.