Coronary artery bypass graft
During coronary artery bypass graft (CABG) surgery, your surgeon will use a healthy blood vessel from another part of your body to create an alternate route, or bypass, around narrowed or blocked sections of your coronary arteries. This bypass surgery allows more blood to reach your heart muscle.
Your medical team will monitor your vital signs, such as blood pressure, heart rhythm, and blood oxygen levels.
Opening the chest
Your surgeon will make a cut, or incision, in the middle or side of your chest. He or she may cut through your breastbone and spread apart your rib cage. The rib cage is opened to expose all internal organs within your chest cavity (a process called a sternotomy). Your surgeon next cuts through the saclike lining that protects the heart (pericardium) to access the heart itself. Your coronary arteries lie on both the front and back surfaces of the heart.
Harvesting a vein to use as a graft blood vessel
The surgeon can remove a piece of healthy blood vessel from these places in the body:
- The inside of your leg
- Your forearm
- Just behind your chest wall
These blood vessels will be used as bypass grafts around narrowed or blocked portions of your coronary arteries.
Leg and arm. While your chest cavity is being opened, the surgeon’s assistant may begin to remove, or harvest, a healthy blood vessel from your arm (radial artery) or leg (saphenous vein).
Using a chest-wall artery for a graft vessel
Besides your saphenous vein and radial arteries, other blood vessels can be used as bypass grafts. In fact, given that they are located close to the heart and coronary arteries, the left and right internal mammary arteries (LIMA and RIMA) are actually favored by many doctors. These arteries have two distinct advantages besides their location:
- Mammary arteries are already attached to the main artery (the aorta). This means that only its other end must be disconnected and grafted onto the diseased coronary artery.
- Because they are arteries, the LIMA and RIMA are more accustomed to a forceful blood flow than a saphenous vein. (Veins carry blood from the body back to the heart and aren’t under as much pressure.) So the LIMA or RIMA may prove to be more durable in the years after your surgery.
Putting you on the heart-lung bypass machine
After your coronary arteries have been exposed and a usable blood vessel segment has been harvested, your surgical team may place you on a heart-lung bypass machine. Alternately, your surgical team may do the operation while your heart is beating. If you are placed on the heart-lung bypass machine, your heart will be temporarily stopped during the surgery so your surgeon can perform surgery on your coronary arteries. The heart-lung bypass machine does the work of your heart and lungs so that all the parts of your body still receive the oxygen-rich blood they need to survive.
While the ventilator physically inflates and deflates your lungs, the bypass machine performs the lungs’ main job of adding oxygen and removing unwanted gases from your blood. Also, the machine circulates that blood through your body.