Heart Bypass Surgery: Overview

Heart bypass surgery, or coronary artery bypass graft (CABG) surgery, is done when coronary arteries, which supply your heart with oxygenated blood, become blocked or damaged. If these arteries are blocked or blood flow is restricted, the heart doesn’t work properly. This surgery may be recommended for those with obstructive coronary artery disease (CAD), which means that plaque has built up in the arteries to the point that it is blocking the supply of blood to the heart. This blockage is usually the result of an accumulation of inflammatory cells and fatty material (composed of cholesterol, calcium, and fibrin) called plaque.

What Is Heart Bypass Surgery?

A heart bypass procedure involves attaching (grafting) a blood vessel taken from elsewhere in the body to the diseased coronary artery. This results in a redirection of the blood flow around the blockage. When a person has a double (or triple) bypass surgery, it means that two or three arterial blockages are rerouted.

Heart bypass surgery is done as an inpatient procedure. It's often a planned procedure, but in some instances, an emergency heart bypass procedure is performed after a person has a heart attack.

Heart bypass surgery may sometimes be performed on infants and children, but not for the same reason adults have the procedure done. Rather, infants and children would be more likely to need heart bypass surgery because of congenital (present at birth) heart disease.

The steps involved in a traditional open method of heart bypass surgery include:

1. The anesthesiologist administers medication to induce unconsciousness (put you to sleep) so that your surgery is pain-free. 
2. The surgeon will make an incision in the middle of the chest and the breastbone is separated to allow for an opening to perform the surgery.
3. You may be connected to a machine called a cardiopulmonary bypass pump (CPB), sometimes called a heart-lung bypass machine, which takes over the function of the heart—while your heart is stopped—so that the surgeon can perform the procedure. 
4. The surgeon will construct the bypass graft by taking a healthy vein or artery (from a different part of the body) and using it to build the bypass around the blocked coronary artery. Often, the saphenous vein—from the leg—is used to create the bypass. In this instance, an incision is made along the inside of the leg to remove the saphenous vein.
5. The saphenous vein is connected to the blocked artery (below the area where the blockage exists) on one end and then to the aorta (via an opening that is created) at the other end. Blood can now travel through the newly constructed artery, bypassing the blockage. There are other arteries that may be used as grafts in bypass surgery, including the radial artery in the wrist and the internal mammary artery (IMA) in the chest. Note, IMA-sourced grafts are said to be superior to vein grafts because they are able to withstand the blood pressure over time. this results in better outcomes, which reduces the incidence of the future need for re-operation.
6. Depending on how many blocked arteries you have, the surgeon may perform more than one coronary artery bypass procedure during the same surgery.
7. Once the graft has been completed, the breastbone is closed (using wires that stay inside the body). The incision is then sutured. 

The duration of the surgery is about four to six hours. After the procedure, you will be taken to the intensive care unit (ICU) or the coronary intensive care unit (CICU) to recover.

Various Surgery Techniques 

There are several variations of the surgical technique that differ from an open CABG procedure, these include:

Off-Pump Coronary Artery Bypass (OPCAB)

An off-pump coronary artery bypass does not employ the cardiopulmonary bypass pump (CPB). The operation is done while the heart is beating.

Minimally Invasive Direct Coronary Artery Bypass (MIDCAB)

MIDCAB is a less invasive procedure with a minimal (2.5 inch) opening in which an artery is harvested directly or by utilizing a surgical robot. It is performed while the heart is still beating so the heart-lung bypass machine is not required.

This procedure has several advantage such as a quicker recovery time, fewer side effects, and a decrease in the need for blood transfusions.

Totally Endoscopic Coronary Artery Bypass (TECAB)

TECAB is performed through four to five fingertip-sized slits with the help of the da Vinci Surgical System. This system enables the surgeon better control and precision than traditional surgical methods.

This procedure, however, has not been broadly adopted by the cardiothoracic surgical community, and there is no randomized trial evidence documenting any superiority over the standard coronary artery bypass graft (CABG) procedure. While the operative time is longer, recovery time may be shorter than the traditional CABG procedure.

The robot doesn’t actually perform the surgery, but rather, acts as a tool that the surgeon controls from a nearby console. A very small camera, attached to the robotic arms, provides a three-dimensional view of the operating space inside the thorax (chest). The advantages of robotic surgery include:

• Quicker recovery times
• Much smaller incisions (without the need to split the breastbone open)
• Quicker pain resolution and minimal blood loss
• Ideal for elderly people with weakened bones (due to osteoporosis) because the breastbone does not have to be cut, which would require re-growth and healing after surgery.
• The heart continues beating during the surgery, so the heart-lung bypass machine is not required.
• Most often, internal mammary artery grafts are used; grafts from other parts of the body, which may not be as strong in withstanding the blood pressure, are infrequently used.

Hybrid Technique (Bypass plus stenting)

A hybrid bypass procedure is a MIDCAB or TECAB combined with stenting techniques. A hybrid technique may be recommended for those with multiple blockages, or in people who do not qualify to have all blockages repaired via minimally invasive surgery.

The combined procedure involves very small incisions and guide catheters used to insert a stent (a small mesh tube) which helps to enlarge part of the artery to improve blood flow. This approach offers the advantage of having two procedures (the coronary bypass surgery and the stenting technique) in one operation.

Other advantages of the hybrid technique include:

• Reduction in blood loss
• Smaller incisions
• Quicker recovery times
• The long-term benefit of having surgery, plus stenting.

Each type of procedure has its own complexities, benefits, risks, prerequisites, and contraindications. Be sure to speak to your surgeon about which procedure is right for you.

Contraindications

Contraindications for heart bypass surgery include those whose coronary arteries aren’t compatible with grafting or heart muscle tissue that isn’t viable to graf. Even if these don't apply to you, bypass surgery will only be considered after weighing the risks and benefits in your case.

This is a major procedure. Your prognosis, age, and any comorbidities, among other things, will all factor into your healthcare provider's recommendation.

Note, although age is not considered a contraindication for having heart bypass surgery, it does pose an increased risk for complications. A 2020 study found that those who were 80 to 89 years old were more likely to develop heart, liver and respiratory complications, and they had a higher mortality (death) rate associated with heart bypass surgery.

Benefits

There are many important benefits to having heart bypass surgery, these include:

• A lower risk of future heart attacks
• A symptom-free life, without pain (such as angina) for up to 15 years
• Longer survival rates compared to those who had other types of surgery (such as angioplasty, a procedure to open blocked blood vessels). 

Potential Risks 

There are many serious risks associated with heart bypass surgery; these include the risk of:

• Bleeding at the graft site: Nearly 30% of those who received a heart bypass surgery required a blood transfusion after the procedure.
• Additional surgery: This may be required due to bleeding and other causes.
• Irregular heart rhythm: Atrial fibrillation, a condition in which the heart quivers instead of pumping and does not sufficiently circulate the blood.
• Blood clots: These may form in the heart and travel to other parts of the body. Clots can contribute to the risk of heart attack, stroke or lung problems.
• Infection: This can occur at the surgical site. It is a rare complication that only occurs in 1% of people who undergo heart bypass surgery.
• Failure of the graft: If this occurs, it may result in a re-operation and/or further treatment.
• Post-pericardiotomy syndrome: A condition that involves symptoms of fever and chest pain; this condition occurs in approximately 30% of those who undergo heart bypass surgery
• Kidney failure: This can result from the surgery, which can inadvertently damage the kidneys, but this is usually temporary.
• Memory loss: The cause of this complication is unknown, but one theory is that it may be linked to the use of the heart-lung machine, which could dislodge minute particles of fatty build-up from an artery to travel to the brain.
• Complications of general anesthesia: There is a risk of pneumonia occurring, as with any type of surgical procedure.
• Death: This is rare, but when death occurs in-hospital after the procedure, it is usually caused by a heart attack or stroke.

There has been a dramatic reduction in the incidence of serious complications associated with a heart bypass surgeries. In fact, in 95% of the cases of heart bypass surgeries, there are no serious complications and the risk of death is as low as 1-2%. But, in spite of this good news, it's still important to discuss the risks and benefits of heart bypass surgery with your healthcare provider. 

Purpose of Heart Bypass Surgery

The primary purpose of heart bypass surgery is to ensure adequate blood flow and oxygenation to the heart muscle, for those who have coronary artery disease, associated with:

• Angina: The primary symptom of coronary artery disease involving chest pain from ischemia (loss of blood flow and adequate oxygen to the heart).
• Coronary artery stenosis: A condition involving atherosclerotic plaques that are made up of cholesterol deposits. The plaques occlude the passage of normal blood flow in one or more or the arteries that supply oxygen to the heart muscle.
• Myocardial infarction (heart attack): This results from blocked coronary arteries (a heart bypass procedure may be performed when the blockage is so severe, it doesn’t respond to other types of treatment).

How to Prepare

There are many things to do when preparing for heart bypass surgery, such as:

• Stop taking certain types of medication: Before surgery, some medications, like blood thinners, should not be taken. Your surgeon will review with you which medicines to take, and which ones you should stop taking before your scheduled procedure.
• Abstain from alcohol use and stop smoking: These behaviors have been linked with several serious complications of surgery. Studies show that the sooner you stop these behaviors before your scheduled surgery, the lower your risk of complications.
• Eat a healthy diet and engage in a regular workout routine: Be sure to consult with your healthcare provider before beginning any type of exercise.
• Arrange for post-surgery care: Make sure you have someone to take you home from the hospital after your surgery, as well as for a person to help you during the first week at home once you are discharged.
• Take care of personal and legal matters: Consider employing a living will. Although death rarely occurs after a heart bypass surgery, it is a possibility. Therefore, making your end-of-life wishes clear is important to address before your surgery.
• Undergo testing: Your healthcare provider will order several types of lab and imaging tests to ensure you are healthy enough for surgery. These tests will be done in the upcoming days or weeks before surgery.
• Attend your preoperative exam appointment: Make sure to attend all appointments before your surgery and follow your surgeon's advice explicitly on how to prepare for your surgery. Common instructions include specific steps on how to shower the night before and the morning of surgery, as well as taking nothing by mouth for a specific amount of time (typically 12 hours) before surgery.

What to Expect on the Day of Surgery

On the day of your surgery, you will go to the hospital and check in before your procedure, you will also:

• Drink and eat nothing: Nothing is to be consumed by mouth on the day of your heart bypass surgery.
• Take any prescribed medications: Take only the medications ordered by your surgeon the day of surgery (with a very small sip of water).
• Check-in: Once you arrive at the hospital’s admitting area, you will meet with the nurse who will start an IV (a needle placed in the arm to administer fluids and drugs before, during, and after your procedure). The nurse will also have you sign consent forms that state you understand your procedure and the risks involved, and that you consent to the surgery.
• Talk to your anesthesiologist: They will explain what type of medicine (anesthesia) you will be getting along with some basic teaching about the risks and benefits of the anesthesia. The anesthesiologist will answer any questions you have.
• Transfer to the surgical suite: Here, the anesthesiologist will administer the medication (anesthesia) that will put you to sleep during the procedure.
• Awaken in the recovery room: After your surgery, you will be in the cardiac intensive care unit (CICU) or surgical intensive care unit (ICU) after your procedure.
• Be very closely monitored: While in the CICU or ICU, frequent assessments by nursing staff and monitors (such as ECG or EKG monitors) will be used to trace your breathing, blood pressure, oxygen level, and other vital readings.
• Be moved to a regular hospital bed: This will happen once your surgeon deems you are stable and ready to be moved.
• Stay in the hospital for several days (or longer): This depends on how fast you recover and your surgeon’s orders.

Recovery

Although everyone recovers from heart bypass surgery differently, there are some general rules of thumb. You should be able to:

• Sit in a chair after the first day.
• Walk down the hall on day three.
• Walk up and down the stairs on day five or six.
• Make a full recovery in approximately 12 weeks after your surgery.

Be sure to follow the orders of your surgeon or other health-care providers regarding when it's okay to partake in certain activity after your heart bypass surgery.

Long-Term Care 

Getting home after heart bypass surgery is just the first step in a long process of recovery. There are many aspects of preventative care required to manage risk factors linked with heart disease that will be important in the upcoming weeks and months, including:

• Quitting smoking and controlling alcohol use
• Eating a heart healthy diet
• Managing stress
• Losing weight (for those who are overweight or obese)
• Exercising and employing other healthy lifestyle measures

These are just a few examples of things that will be important to your long-term recovery. Keep in mind that there are many sources of support to help you along the way, such as support groups, nutritionists and other medical professionals to help you implement these and other healthy lifestyle changes. 

A Word From Verywell

If you or a loved one is having heart bypass surgery, keep an open line of communication with your healthcare provider and surgeon. Don't hesitate to bring up any thoughts or questions that come to mind. If you can, bring along a loved one to help you take notes and understand the procedure. Make sure to pay attention to not only the details of the procedure but also any post-operative instructions. Knowing what's ahead, will help you throughout your journey.