heart bypass

What is a heart bypass

Heart bypass is often referred to as coronary artery bypass surgery or coronary artery bypass graft (CABG), is a common surgical procedure to treat coronary heart disease (coronary artery disease), which is when the arteries that supply your heart muscle with oxygen-rich blood (the coronary arteries) become narrowed by a gradual build-up of fatty material (atheroma) within their walls. Coronary artery bypass surgery involves taking a healthy blood vessel from another part of your body – usually the chest, leg or arm – and using it to bypass the blocked or narrowed coronary artery. The new blood vessel is called a graft, and it helps to reroute blood around the narrowed part of the artery, which improves the supply of blood and oxygen to the heart muscle.

The number of coronary artery bypasses you need depends on where in your heart and how severe your blockages are. You’re said to have single-, double-, or triple-artery disease depending on the number of coronary arteries that are narrowed. For some people, coronary heart disease can be managed with just medication and lifestyle changes. For those whose arteries are more extensively affected, heart bypass can be an option. Heart bypass is done to improve the symptoms of coronary artery disease and help reduce the chances of having a heart attack.

Although coronary artery bypass surgery doesn’t cure the heart disease that caused the blockages (atherosclerosis or coronary artery disease), it can ease symptoms, such as chest pain and shortness of breath. For some people, this procedure can improve heart function and reduce the risk of dying of heart disease.

Doctors called cardiothoracic surgeons do the coronary artery bypass surgery.

Coronary artery bypass surgery generally takes between three and six hours and requires general anesthesia.

Most coronary bypass surgeries are done through a long incision in the chest also called open heart bypass surgery, while a heart-lung machine keeps blood and oxygen flowing through your body. This is called on-pump coronary bypass surgery.

The surgeon cuts down the center of the chest, along the breastbone. He or she then spreads open the rib cage to expose the heart. After the chest is opened, the heart is temporarily stopped with medication and a heart-lung machine takes over to circulate blood to the body.

Other coronary artery bypass surgical techniques your surgeon might use include:

  • Off-pump or beating-heart surgery. This procedure allows surgery to be done on the beating heart using special equipment to stabilize the area of the heart the surgeon is working on. This type of surgery is challenging because the heart is still moving. It’s not an option for everyone.
  • Minimally invasive surgery. A surgeon performs coronary bypass through small incisions in the chest, often with the use of robotics and video imaging that help the surgeon operate in a small area. Variations of minimally invasive surgery might be called port-access or keyhole surgery.

The surgeon will take an artery or vein from your body—for example, from your chest or leg—to use as the bypass graft. For surgeries with several bypasses, both artery and vein grafts are commonly used.

  • Artery grafts. These grafts are much less likely than vein grafts to become blocked over time. The left internal mammary artery most often is used for an artery graft. This artery is located inside the chest, close to the heart. Arteries from the arm or other places in the body also are used.
  • Vein grafts. Although veins are commonly used as grafts, they’re more likely than artery grafts to become blocked over time. The saphenous vein—a long vein running along the inner side of the leg—typically is used.

After completing the graft, the surgeon will restore your heartbeat, disconnect you from the heart-lung machine and use wire to close your chest bone. The wire will remain in your body after the bone heals.

Most people make a full recovery within 12 weeks, although it varies between individuals.

Coronary artery bypass surgery might also be performed in emergency situations, such as a heart attack, if you’re not responding to other treatments.

Even with coronary artery bypass surgery, you’ll need to make lifestyle changes after surgery. Medications are prescribed routinely after coronary bypass surgery to lower your blood cholesterol, reduce the risk of developing a blood clot and help your heart function as well as possible.

Figure 1. Heart coronary arteries

Heart coronary arteries

How long do heart bypass grafts last?

People tend to do very well after heart bypass and most get a good 15 years before needing another intervention, which at that point would almost always be having a stent inserted. Redoing heart bypass could also be an option if stenting weren’t suitable. It’s important to remember that heart bypass doesn’t cure the underlying coronary heart disease (coronary artery disease), so look after your heart health by following the lifestyle advice that’s been recommended and continue taking any prescribed medication.

How long is a heart bypass operation?

On average, the operation takes three and a half hours.

What is open-heart surgery?

Open-heart surgery is any kind of surgery in which a surgeon makes a large incision (cut) in your chest to open the rib cage and operate on the heart. “Open” refers to the chest, not the heart. Depending on the type of surgery, the surgeon also may open the heart.

Once the heart is exposed, the patient is connected to a heart-lung bypass machine. The machine takes over the heart’s pumping action and moves blood away from the heart. This allows the surgeon to operate on a heart that isn’t beating and that doesn’t have blood flowing through it.

Open-heart surgery is used to do coronary artery bypass surgery, repair or replace heart valves, treat atrial fibrillation, do heart transplants, and place ventricular assist devices (VADs) and total artificial hearts (TAHs).

Will I have a scar?

The traditional heart surgery technique will create a long scar down the middle of the breastbone. There will also be scars on the legs and/or arms if blood vessels are removed from these sites. The size can vary depending on the technique used to remove the blood vessel. Scars will be pink at first and usually fade over time.

What is minimally invasive heart surgery?

For minimally invasive heart surgery, a surgeon makes small incisions (cuts) in the side of the chest between the ribs. This type of surgery may or may not use a heart-lung bypass machine.

Minimally invasive heart surgery is used to do some bypass and maze surgeries. It’s also used to repair or replace heart valves, insert pacemakers or implantable cardioverter defibrillator (ICDs), or take a vein or artery from the body to use as a bypass graft for coronary artery bypass grafting (CABG).

One type of minimally invasive heart surgery that is becoming more common is robotic-assisted surgery. For this surgery, a surgeon uses a computer to control surgical tools on thin robotic arms.

The tools are inserted through small incisions in the chest. This allows the surgeon to do complex and highly precise surgery. The surgeon always is in total control of the robotic arms; they don’t move on their own.

What is minimally invasive heart bypass surgery?

Minimally invasive heart bypass surgery is done without stopping the heart and putting the patient on a heart-lung machine. A 3 to 5 inch (8 to 13 cm) incision is made in the left part of the chest between the ribs. This incision is much less traumatic than the traditional heart bypass surgery incision which separates the breast bone. Minimally invasive heart bypass surgery allows the patient less pain and a faster recovery.

Figure 2. Open heart bypass surgery versus minimally invasive heart bypass surgery

Open heart bypass surgery versus minimally invasive heart bypass surgery

Heart bypass surgery types

There are several types of coronary artery bypass grafting (CABG). Your doctor will recommend the best option for you based on your needs.

Traditional coronary artery bypass surgery

Traditional coronary artery bypass grafting (CABG) is used when at least one major artery needs to be bypassed. During the surgery, the chest bone is opened to access the heart.

Medicines are given to stop the heart; a heart-lung bypass machine keeps blood and oxygen moving throughout the body during surgery. This allows the surgeon to operate on a still heart.

After surgery, blood flow to the heart is restored. Usually, the heart starts beating again on its own. Sometimes mild electric shocks are used to restart the heart.

Off-Pump coronary artery bypass surgery

This type of coronary artery bypass grafting (CABG) is similar to traditional coronary artery bypass surgery because the chest bone is opened to access the heart. However, the heart isn’t stopped, and a heart-lung bypass machine isn’t used. Off-pump coronary artery bypass surgery sometimes is called beating heart bypass grafting.

Minimally invasive direct coronary artery bypass surgery

This type of surgery differs from traditional coronary artery bypass surgery because the chest bone isn’t opened to reach the heart. Instead, several small cuts are made on the left side of the chest between the ribs. This type of surgery mainly is used to bypass blood vessels at the front of the heart.

Minimally invasive bypass grafting is a fairly new procedure. It isn’t right for everyone, especially if more than one or two coronary arteries need to be bypassed.

Why is heart bypass surgery done?

Coronary artery bypass surgery is one option if you have a blocked artery to your heart. Your heart needs a constant supply of oxygen-rich blood to survive, and this is supplied by blood vessels called coronary arteries, located on the outside of the heart. The heart has three major coronary arteries: two of these arise from the left main coronary artery, which then branches into two; and the other major artery is called the right coronary artery. Over time, fatty deposits can build up on the inside of these arteries, causing coronary artery disease and reducing blood flow to the heart. When this happens, you can develop symptoms such as chest pain – angina – and you may become short of breath. You are also more at risk of a heart attack.

You and your doctor might consider heart bypass surgery if:

  • You have severe chest pain caused by narrowing of several of the arteries that supply your heart muscle, leaving the muscle short of blood during even light exercise or at rest.
  • You have more than one diseased coronary artery, and the heart’s main pumping chamber — the left ventricle — isn’t functioning well.
  • Your left main coronary artery is severely narrowed or blocked. This artery supplies most of the blood to the left ventricle.
  • You have an artery blockage for which temporarily inserting and inflating a tiny balloon to widen the artery (angioplasty) isn’t appropriate, you’ve had a previous angioplasty or placement of a small wire mesh tube (stent) to hold the artery open that hasn’t been successful, or you’ve had stent placement, but the artery has narrowed again (restenosis).

Who needs heart bypass surgery?

Coronary artery bypass grafting (CABG) is used to treat people who have severe coronary heart disease (coronary artery disease) that could lead to a heart attack. coronary artery bypass also might be used during or after a heart attack to treat blocked arteries.

Your doctor may recommend coronary artery bypass if other treatments, such as lifestyle changes or medicines, haven’t worked. He or she also may recommend coronary artery bypass if you have severe blockages in your large coronary (heart) arteries, especially if your heart’s pumping action has already grown weak.

Coronary artery bypass also might be a treatment option if you have blockages in your coronary arteries that can’t be treated with percutaneous coronary intervention (PCI), also known as coronary angioplasty or percutaneous coronary angioplasty (PTCA).

Your doctor will decide whether you’re a candidate for coronary artery bypass based on factors such as:

  • The presence and severity of coronary artery disease symptoms
  • The severity and location of blockages in your coronary arteries
  • Your response to other treatments
  • Your quality of life
  • Any other medical problems you have

Physical exam and diagnostic tests

To find out whether you’re a candidate for coronary artery bypass, your doctor will give you a physical exam. He or she will check your heart, lungs, and pulse.

Your doctor also may ask you about any symptoms you have, such as chest pain or shortness of breath. He or she will want to know how often and for how long your symptoms occur, as well as how severe they are.

Your doctor will recommend tests to find out which arteries are clogged, how much they’re clogged, and whether you have any heart damage.

EKG (Electrocardiogram)

An EKG or ECG is a simple test that detects and records your heart’s electrical activity. The test shows how fast the heart is beating and its rhythm (steady or irregular). An EKG also records the strength and timing of electrical signals as they pass through each part of the heart.

An EKG can show signs of heart damage due to coronary artery disease and signs of a previous or current heart attack.


Echocardiography (echo) uses sound waves to create a moving picture of your heart. The test shows the size and shape of your heart and how well your heart chambers and valves are working.

Echo also can show areas of poor blood flow to the heart, areas of heart muscle that aren’t contracting normally, and previous injury to the heart muscle caused by poor blood flow.

There are several types of echo, including stress echo. This test is done both before and after a stress test. A stress echo usually is done to find out whether you have decreased blood flow to your heart, a sign of coronary artery disease.

Stress Test

Some heart problems are easier to diagnose when your heart is working hard and beating fast.

During stress testing, you exercise to make your heart work hard and beat fast while heart tests are done. If you can’t exercise, you may be given medicine to raise your heart rate.

The heart tests done during stress testing may include nuclear heart scanning, echo, and positron emission tomography (PET) scanning of the heart.

Coronary Angiography and Cardiac Catheterization

Coronary angiography is a test that uses dye and special x rays to show the insides of your coronary arteries.

To get the dye into your coronary arteries, your doctor will use a procedure called cardiac catheterization.

A thin, flexible tube called a catheter is put into a blood vessel in your arm, groin (upper thigh), or neck. The tube is threaded into your coronary arteries, and the dye is released into your bloodstream.

Special x rays are taken while the dye is flowing through the coronary arteries. The dye lets your doctor study blood flow through the heart and blood vessels. This helps your doctor find blockages that can cause a heart attack.

Other Considerations

When deciding whether you’re a candidate for coronary artery bypass, your doctor also will consider your:

  • History and past treatment of heart disease, including surgeries, procedures, and medicines
  • History of other diseases and conditions
  • Age and general health
  • Family history of coronary artery disease, heart attack, or other heart diseases

Your doctor may recommend medicines and other medical procedures before coronary artery bypass. For example, he or she may prescribe medicines to lower your cholesterol and blood pressure and improve blood flow through your coronary arteries.

PTCA (percutaneous coronary angioplasty) also might be tried. During this procedure, a thin, flexible tube with a balloon at its tip is threaded through a blood vessel to the narrow or blocked coronary artery.

Once in place, the balloon is inflated, pushing the plaque against the artery wall. This creates a wider path for blood to flow to the heart.

Sometimes a stent is placed in the artery during PTCA (percutaneous coronary angioplasty). A stent is a small mesh tube that supports the inner artery wall.

What happens during heart bypass?

Coronary artery bypass grafting (CABG) requires a team of experts. A cardiothoracic surgeon will do the surgery with support from an anesthesiologist, perfusionist (heart-lung bypass machine specialist), other surgeons, and nurses.

There are several types of coronary artery bypass surgery. They range from traditional surgery to newer, less-invasive methods.

On average, heart bypass takes about three and a half hours and requires general anesthesia. For general anesthesia, a breathing tube is inserted through your mouth. This tube attaches to a ventilator, which breathes for you during and immediately after the surgery.

Open heart bypass surgery

The surgeon needs to access your heart, and in the open heart bypass surgery also called traditional heart surgery technique, this involves cutting the breastbone to expose the heart. It’s also possible to access the heart using a smaller incision that is made directly over the area where the artery is affected, but this technique is not suitable for all patients.

Next, blood vessels are removed from the legs, the saphenous vein is harvested from the inside of your leg and/or arms and prepared to provide the new grafts. Pieces of this great vein will be used to bypass the blocked arteries in your heart. The venous graft is sewn to the aorta and to the affected coronary artery past the blocked site. The internal mammary artery from the chest may also be used to bypass a clogged artery. Several arteries may be bypassed depending on the condition of your heart.

In most cases, the heart is then stopped and the blood is diverted to a heart-lung machine that takes over the pumping function. In ‘off-pump’ or ‘beating heart’ surgery, the heart-lung machine is not required, because the surgery is performed without stopping the heart. The choice of technique depends on the individual surgeon, but excellent results are achieved with both.

After the heart has been stopped (or while it is still beating, if during ‘off-pump’ surgery), the prepared grafts will be used to bypass the narrowed areas in your coronary arteries.

Once the narrowed arteries have been bypassed, the heart will be restarted and the blood will slowly be allowed to re-enter the heart from the heart-lung machine. Once the heart has taken over pumping, the heart-lung machine is turned off.

When the surgeon is satisfied that the operation is complete, the breastbone is securely closed using wires that will stay in place permanently. Sutures are then used to close the skin on the chest and on any cuts made to remove blood vessels.

Nontraditional coronary artery bypass surgery

Nontraditional coronary artery bypass surgery includes off-pump coronary artery bypass surgery and minimally invasive coronary artery bypass surgery.

Off-Pump Coronary Artery Bypass Surgery

Surgeons can use off-pump coronary artery bypass surgery to bypass any of the coronary (heart) arteries. Off-pump coronary artery bypass surgery is similar to traditional coronary artery bypass surgery because the chest bone is opened to access the heart.

However, the heart isn’t stopped and a heart-lung-bypass machine isn’t used. Instead, the surgeon steadies the heart with a mechanical device.

Off-pump coronary artery bypass surgery sometimes is called beating heart bypass grafting.

Minimally Invasive Direct Coronary Artery Bypass Surgery

There are several types of minimally invasive direct coronary artery bypass (MIDCAB) grafting. These types of surgery differ from traditional bypass surgery because the chest bone isn’t opened to reach the heart. Also, a heart-lung bypass machine isn’t always used for these procedures.

  • Minimally invasive direct coronary artery bypass (MIDCAB) procedure. This type of surgery mainly is used to bypass blood vessels at the front of the heart. Small incisions are made between your ribs on the left side of your chest, directly over the artery that needs to be bypassed. The incisions usually are about 3 inches long. (The incision made in traditional coronary artery bypass surgery is at least 6 to 8 inches long.) The left internal mammary artery most often is used for the graft in this procedure. A heart-lung bypass machine isn’t used during MIDCAB grafting.
  • Port-access coronary artery bypass procedure. The surgeon does this procedure through small incisions (ports) made in your chest. Artery or vein grafts are used. A heart-lung bypass machine is used during this procedure.
  • Robot-assisted technique. This type of procedure allows for even smaller, keyhole-sized incisions. A small video camera is inserted in one incision to show the heart, while the surgeon uses remote-controlled surgical instruments to do the surgery. A heart-lung bypass machine sometimes is used during this procedure.

Heart bypass surgery recovery

The average stay in hospital after heart bypass is six nights and usually consists of about a day or two in the intensive care unit (ICU), one night in the high dependency unit and about four nights on the ward. The breathing tube will remain in your throat until you are awake and able to breathe on your own. Most people are well enough to sit in a chair after one day, walk after three days and walk up and down stairs after five or six days. After a big operation such as heart bypass, it’s normal to feel tired, emotional and uncomfortable. The amount of discomfort varies from person to person, and medication can be given to help.

Cardiac rehabilitation often begins while you’re still in the hospital. You’ll be given a program of exercise and education designed to help you recover. You’ll continue with monitored programs in an outpatient setting until you can safely follow a home-based maintenance program.

Barring complications, you’ll likely be discharged from the hospital within a week. You still might have difficulty doing everyday tasks or walking a short distance. If, after returning home, you have any of the following signs or symptoms, call your doctor:

  • Fever
  • Rapid heart rate
  • New or worsened pain around your chest wound
  • Reddening around your chest wound or bleeding or other discharge from your chest wound

Expect a recovery period of about six to 12 weeks. In most cases, you can return to work, begin exercising and resume sexual activity after four to six weeks, but make sure you have your doctor’s OK before doing so.

Recovery at home

Your doctor will give you specific instructions for recovering at home, especially concerning:

  • How to care for your healing incisions
  • How to recognize signs of infection or other complications
  • When to call the doctor right away
  • When to make followup appointments

You also may get instructions on how to deal with common side effects from surgery. Side effects often go away within 4 to 6 weeks after surgery, but may include:

  • Discomfort or itching from healing incisions
  • Swelling of the area where an artery or vein was removed for grafting
  • Muscle pain or tightness in the shoulders and upper back
    Fatigue (tiredness), mood swings, or depression
  • Problems sleeping or loss of appetite
  • Constipation
  • Chest pain around the site of the chest bone incision (more frequent with traditional coronary artery bypass surgery)

For the first two or three days at home, people should try to do about the same amount of moving around and walking exercise as they did with the physiotherapist during their last couple of days in hospital. After a few days, it’s OK to slowly increase activity levels. Walking is ideal, but before leaving hospital, it’s good to ask the medical team how much activity is appropriate and what the safest way to increase it is.

Wound infections can sometimes occur nine to 10 days after surgery. Signs of a possible infection can include the wound becoming more painful or looking red, inflamed or swollen. If this happens, you should contact the medical team involved in the operation. Wound infections can usually be treated successfully with antibiotics if they are diagnosed early.

Full recovery from traditional coronary artery bypass surgery may take 6 to 12 weeks or more. Less recovery time is needed for nontraditional coronary artery bypass surgery.

Cardiac rehabilitation

Cardiac rehabilitation is absolutely fundamental. The hospital where you’ve been treated should invite you to go on a cardiac rehabilitation program and this usually starts around six weeks after you leave hospital. People who attend cardiac rehabilitation are more likely to get the full benefits of their surgery, have a better quality of life and have fewer hospital admissions.

Ongoing Care

Care after coronary artery bypass surgery may include periodic checkups with doctors. During these visits, tests may be done to see how your heart is working. Tests may include ECG (electrocardiogram), stress testing, echocardiography, and cardiac CT.

Coronary artery bypass surgery is not a cure for coronary heart disease (coronary artery disease). You and your doctor may develop a treatment plan that includes lifestyle changes to help you stay healthy and reduce the chance of coronary artery disease getting worse.

Lifestyle changes may include making changes to your diet, quitting smoking, doing physical activity regularly, and lowering and managing stress.

Your doctor also may refer you to cardiac rehabilitation (rehab). Cardiac rehab is a medically supervised program that helps improve the health and well-being of people who have heart problems.

Rehab programs include exercise training, education on heart healthy living, and counseling to reduce stress and help you return to an active life. Doctors supervise these programs, which may be offered in hospitals and other community facilities. Talk to your doctor about whether cardiac rehab might benefit you.

Taking medicines as prescribed also is an important part of care after surgery. Your doctor may prescribe medicines to manage pain during recovery; lower cholesterol and blood pressure; reduce the risk of blood clots forming; manage diabetes; or treat depression.

Heart bypass surgery recovery time

This can vary from person to person, but most people find that it takes between two and three months to make a full recovery. People over the age of 80 may find recovery takes longer than this. It’s not unusual for it to take six months to a year to derive the full benefits of heart bypass surgery.

Your doctor will tell you when you can start physical activity again. It varies from person to person, but there are some typical timeframes. Most people can resume sexual activity within about 4 weeks and driving after 3 to 8 weeks.

Returning to work after 6 weeks is common unless your job involves specific and demanding physical activity. Some people may need to find less physically demanding types of work or work a reduced schedule at first.

Heart bypass surgery risks

Heart bypass is safer than ever, but as with all operations, there are risks, and any operation puts the body under stress. The risk of developing complications depends on a number of things, including your health before the surgery. About one in 10 people will experience significant memory loss after surgery, but the vast majority affected will fully recover from this. Reduced kidney function also happens in about one in three people and usually resolves in the days following surgery. Major complications, such as stroke, carry a general risk of one to two per cent. Your doctor can advise you on your risk as an individual.

Because coronary bypass surgery is an open-heart surgery, you might have complications during or after your procedure. Possible complications include:

  • Reactions to anesthesia
  • Bleeding
  • Heart rhythm irregularities (arrhythmias)
  • Infections of the chest wound
  • Memory loss or troubles with thinking clearly, which often improve within six to 12 months
  • Kidney problems
  • Stroke
  • Heart attack, if a blood clot breaks loose soon after surgery
  • Death

Your risk of developing complications is generally low, but it depends on your health before surgery. Your risk of complications is higher if the operation is done as an emergency procedure or if you have other medical conditions, such as emphysema, kidney disease, diabetes or blocked arteries in your legs (peripheral artery disease).

Some patients have a fever associated with chest pain, irritability, and decreased appetite. This is due to inflammation involving the lung and heart sac.

This complication sometimes occurs after surgeries that involve cutting through the pericardium (the outer covering of the heart). The problem usually is mild, but some patients may develop fluid buildup around the heart that requires treatment.

Memory loss and other issues, such as problems concentrating or thinking clearly, might occur in some people.

These problems are more likely to affect older patients and women. These issues often improve within 6–12 months of surgery.

In general, the risk of complications is higher if heart bypass surgery is done in an emergency situation (for example, during a heart attack). The risk also is higher if you have other diseases or conditions, such as diabetes, kidney disease, lung disease, or peripheral arterial disease (P.A.D.).

Heart bypass surgery results

After surgery, most people feel better and might remain symptom-free for as long as 10 to 15 years. Over time, however, it’s possible that other arteries or even the new graft used in the bypass will become clogged, requiring another bypass or angioplasty.

Your results and long-term outcome will depend in part on taking your medications to prevent blood clots, lower blood pressure, lower cholesterol and help control diabetes as directed, and following healthy lifestyle recommendations, including these:

  • Stop smoking.
  • Follow a healthy-eating plan, such as the DASH diet.
  • Achieve and maintain a healthy weight.
  • Exercise regularly.
  • Manage stress.

Heart bypass surgery prognosis

The results of coronary artery bypass surgery usually are excellent. The surgery improves or completely relieves angina symptoms in most patients. Although symptoms can recur, many people remain symptom-free for as long as 10 to 15 years. Coronary artery bypass surgery also may lower your risk of having a heart attack and help you live longer.

You may need repeat surgery if blockages form in the grafted arteries or veins or in arteries that weren’t blocked before. Taking medicines and making lifestyle changes as your doctor recommends can lower the risk of a graft becoming blocked.

Health Jade Team

The author Health Jade Team

Health Jade