Health library

Bypass surgery is one of the most common and effective ways to treat severe blockages of blood to the heart muscle.

Some people who have heart disease can improve their health by taking medicines or undergoing angioplasty to improve blood flow to the heart.

But for other people, cardiac bypass surgery offers the best treatment.

Bypass surgery may be done when arteries that carry nutrient-rich blood to the heart become clogged or blocked, cutting off blood flow and possibly causing chest pain or a heart attack.

Bypass surgery creates a detour—a bypass—that allows blood to move around the clogged arteries.

Doctors use segments of healthy blood vessels from another part of the body—usually from the leg or chest wall—to create the new pathway for the blood.

According to the American Heart Association (AHA) and the National Heart, Lung, and Blood Institute (NHLBI), the goals of bypass surgery are to:

• Improve the supply of oxygen and blood to the heart.
• Relieve chest pain.
• Reduce the risk of a heart attack.
• Improve physical activity levels.
• Improve the pumping action of the heart.
• Improve the quality and length of life.

How it's done

According to the NHLBI, coronary artery bypass grafting (CABG) is the most common heart surgery done on adults.

During CABG surgery, the surgeon cuts through the breast bone to work on the heart.

The replacement artery or vein is connected, or grafted, to the blocked artery, bypassing the blocked area.

A person can undergo one, two, three or four bypasses at once, depending on the number of arteries that are clogged. The surgery usually lasts three to six hours, depending on the number of arteries being bypassed.

In most cases, medicines are given to stop the heart during CABG surgery, and a heart-lung machine keeps blood and oxygen moving throughout the body. This allows the surgeon to operate on a heart that is not beating. (When the grafts are in place, the heart is restarted using mild electric shocks.)

However, off-pump CABG may also be done. This procedure does not use the heart-lung machine. Instead, the surgeon uses a mechanical device to keep just part of the heart still while the graft is being done.

According to the NHLBI, risks from coronary bypass surgery are uncommon but can include:

• Infection.
• Fever.
• Pain.
• Reaction to anesthesia.
• Blood clots.
• Stroke, heart attack or death.

Long-term results of traditional CABG are excellent, according to the NHLBI. Many people who have the procedure reduce their symptoms and lower their risk of a heart attack. A person's energy levels usually improve after the surgery as well.

Full recovery from CABG takes 6 to 12 weeks or more.

Minimally invasive approaches

In minimally invasive heart surgery, a surgeon makes small cuts in the side of the chest. This may require use of a heart-lung bypass machine.

Minimally invasive surgery is used for some bypass surgeries. It's also used to repair heart valves, insert pacemakers, and assist with a bypass graft for CABG.

Robotic-assisted surgery, in which a surgeon uses a computer to control surgical tools on thin robotic arms, is becoming more common. This allows the surgeon to do very precise, complex surgery.

Are you a candidate?

Your doctor will help you determine if you're a candidate for traditional CABG or one of the minimally invasive surgeries. A number of factors will be considered, including your overall health and the severity of your heart disease.

Reviewed 1/25/2024