Coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that bypass surgery aims to reroute bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood around blocked heart arteries caused by atherosclerotic plaques—fatty deposits that slow down or block bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood flow.
Much like a road bridge that allows vehicles to cross a river or obstacle, this procedure creates new pathways so that oxygen-rich bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood can continue to nourish the heart muscle, despite existing blockages.
It is important to understand that this surgery does not cure coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that disease. It does not remove the cause of atherosclerosis. However, it can relieve symptoms, improve quality of life, and, in some cases, prolong life by preventing serious complications such as heart attacks.
This text outlines the different steps involved in coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that bypass surgery:
- The progression of the disease that leads to surgery
- Preparation
- How the bypass procedure is performed (video)
- Recovery in the hospital
The progression of the disease that leads to surgery
Before explaining the surgery itself, it’s helpful to review the role of the heart and how it receives oxygen.
The Heart – A Vital Muscle Pump
The heart is a muscle about the size of a fist, located in the center of the chest between the two lungs. It powers the circulatory system, pumping bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood continuously—over 100,000 times a day.
The Heart’s Fuel: Oxygen
Like any muscle, the heart needs oxygen to function. This fuel is delivered to it by the bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood.
The coronary arteries
Oxygen-rich bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood reaches the heart muscle through the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that. These arteries supply the heart directly, and any reduction in this supply can lead to serious, sometimes irreversible, consequences.
Two Main Arteries
There are two main coronary arteries—one on the left and one on the right. They lie directly on the surface of the heart, which makes them accessible to the surgeon.
No Bigger Than a Nail Head
Though essential, the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that are very small—ranging from 1 to 3 millimeters in diameter, about the size of a nail head.
Cholesterol Plaques
As coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that disease progresses—also known as atherosclerotic coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that disease—the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that begin to narrow due to deposits called atheromatous plaques, more commonly referred to as cholesterolCholesterol is essential for the proper functioning of the human body, but it can also have harmful effects if present in excess. >> plaques.
These plaques build up slowly over time. They are made of a mix of fat (cholesterolCholesterol is essential for the proper functioning of the human body, but it can also have harmful effects if present in excess. >>) and calcium that sticks to the inner walls of the arteries.
As these plaques thicken, they start to slow down bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood flow. The heart receives less oxygen, especially during physical effort.
This can lead to angina—a warning sign felt as chest pain, sometimes with shortness of breath or fatigue.
Angina: A Warning Sign
If a coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that becomes severely narrowed—or completely blocked—blood can no longer reach part of the heart. That section of the heart muscle lacks oxygen and begins to suffer.
This often causes intense and persistent chest pain.
If the pain lasts more than 20 to 30 minutes, part of the heart muscle may stop working—or die.
Heart Attack (Myocardial Infarction)
When a part of the heart muscle dies, it is replaced with scar tissue.
This is called a heart attack or myocardial infarction.
Scar tissue cannot contract like healthy heart muscle. Think of it like the tough white strip in a piece of meat—it’s stiff and doesn’t help the heart pump bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood.
What happens next?
The heart becomes less efficient, making it harder to pump bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood through the body.
This can lead to:
- Fatigue
- Shortness of breath
- And over time, heart failure
Tests Leading to Bypass Surgery
It all starts in a healthcare provider’s office, when they suspect coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that disease after listening to the patient and reviewing their symptoms.
Diagnostic tests are then ordered—such as an electrocardiogram (ECG), an echocardiogram, or a stress test.
If the results suggest there may be significant blockages in the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that, a coronary angiogram is usually recommended.
This test allows doctors to directly visualize the heart’s arteries using a contrast dye injected into the blood vessels. It shows the presence, number, and location of blockages—whether partial or complete.
When is surgery considered?
If the angiogram shows that multiple arteries are affected—or that the location of the blockages makes other treatments less effective or impossible—a referral for cardiac surgery is made.
In many cases, this referral is automatic after the angiogram, if the criteria are clearly met.
Preparation
Pre-Admission
Most hospitals that perform heart surgery have a pre-admission service. This means you may need to go to the hospital ahead of time for some preparatory tests.
In some cases, your healthcare provider may order additional tests to speed up the process. These may include:
- A bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood test
- A chest X-ray
- An ultrasound of the carotid arteries in the neck (to ensure blood flow to the brain is not compromised during surgery)
The hospital or the cardiac surgery department will contact you to coordinate the details and set a date for the procedure.
Bring your medication list
During your pre-admission visit, be sure to bring a complete list of your medications.
The surgical team will carefully review it, as some medications may need to be stopped temporarily before the operation.
A Tip Before Leaving Home
Before heading to the hospital for surgery, it’s best to bring only the essentials.
We recommend not bringing any valuables like a phone, computer, radio, or other electronic devices, to reduce the risk of loss or theft during your hospital stay. If needed, these items can be brought to you later, once you’re back on the regular unit after surgery.
For the first few days, the following items are usually sufficient:
- Basic personal hygiene products
- Comfortable clothes for your return home
- An up-to-date list of your medications
Admission and Final Preparations
In most cases, hospital admission for heart surgery takes place the day before the procedure.
It is essential to bring your medications or a complete, up-to-date list so the medical team can review your current treatment accurately.
During this day, you may meet various members of the healthcare team who will be involved before, during, and after the surgery.
In many hospitals, patients are also offered a short visit to the intensive care unit (ICU) to help them become familiar with the environment where they will recover immediately after the operation.
A key step before surgery is signing the informed consent form, if it hasn’t already been completed.
Consent to the Procedure
Signing the surgical consent form confirms that all essential information regarding the planned procedure—particularly the risks associated with the surgery—has been explained clearly and understandably. This is an important step in the surgical process.
- Duration and Course of the Procedure
Preparation by the anesthesia team usually takes between 30 and 60 minutes.
The surgery itself—coronary artery bypass—lasts on average between 2 and 4 hours, depending on the complexity of the case.
Once the procedure is completed, the patient is transferred to the intensive care unit, where close monitoring is provided during the first night.
- Risks Associated with the Surgery
Coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that bypass surgery is widely performed around the world and is considered very safe.
Serious risks associated with the procedure are estimated at around 1 to 2%.
These complications, though rare, may include major events such as death, stroke, or coma.
Such events may occur during surgery, immediately afterward, or in the days following the operation.
- A Commonly Performed Surgery
Bypass surgery is one of the most frequent cardiac procedures worldwide.
Thanks to constant progress in surgical techniques and postoperative care, its success rate remains very high.
- Other Possible Risks
Less serious but more frequent complications may also occur. These include:
- Cardiac arrhythmias (irregular or abnormal heartbeats), seen in about one-third of patients
- The need for a bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood transfusion
- Infections at the surgical site or in the lungs
- And in some cases, temporary kidney problems
The extent of the risks can vary depending on several factors, including age, medical history, and the presence of chronic illnesses. Each clinical situation is unique.
An Informed Decision
After being informed of the risks, benefits, and alternatives to surgery, the person concerned is invited to sign a consent form.
This document confirms that they freely and knowingly accept to undergo the procedure.
Heading to the Operating Room
When it’s time to go to the operating room, the patient must wear a hospital gown.
No underwear, socks, jewelry, or watches are allowed. In addition, nail polish should be removed, as it can interfere with the monitoring of certain parameters during the surgery.
Once again, it is strongly recommended to leave all valuables at home.
Personal belongings are usually transferred between the different hospital units where the patient stays, but since surgery often involves several moves, it’s safer to minimize the risk of loss.
How the bypass procedure is performed
To treat angina or a heart attack, the goal is to restore proper bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood flow through the heart’s arteries.
When these vessels are too narrowed or blocked, a surgery called coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that bypass may be necessary.
A Procedure with a Long History
For more than 50 years, bypass surgery has helped millions of patients regain a better quality of life.
It works by bypassing a blocked artery using a grafted bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood vessel, allowing bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood to flow normally again.
To read: First bypass surgery
Building Bridges
As the name suggests, this surgery creates an alternate route—similar to building a bridge over a blocked river.
Blood is redirected beyond the blockage to supply the heart muscle properly.
Two Types of Grafts
Bypass grafts can be made using two types of vessels:
- Veins, usually taken from the leg
- Arteries, typically taken from the chest
Venous Bypass Grafts
In this type of surgery, a portion of the saphenous vein is removed from the leg.
This segment is then used to bypass the blocked coronary arteryThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that.
Blood return from the leg is not compromised, as neighboring veins take over the role.
Arterial Bypass Grafts
These are often performed using the left internal mammary artery, located inside the chest wall. Once redirected to the heart, it effectively replaces the diseased artery.
The bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood that originally flowed through this artery is naturally redirected by other branches, without causing any issues.
How Many Bypasses?
The number of bypasses depends on how many coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that are blocked.
These blockages are identified through a coronary angiogram, an imaging test that shows the heart’s arteries in detail.
Surgeons often perform 1 to 3 bypasses, but in some cases, 6 or more may be needed depending on the extent of the disease.
The Surgery
Bypass surgery is performed under general anesthesia, which means the patient is completely asleep.
To access the heart, the surgeon makes an incision down the center of the chest to open the rib cage.
This opening provides a safe path to the heart and allows the procedure to begin.
The Beating Heart Becomes Visible
Once the chest is open, the heart becomes visible—constantly moving—between the two lungs.
It can be seen gently sliding within its protective membrane, called the pericardiumThe pericardium is a sac surrounding the heart and containing a lubricating fluid that allows it to glide with each beat without friction..
The pericardiumThe pericardium is a sac surrounding the heart and containing a lubricating fluid that allows it to glide with each beat without friction. is then opened, giving the surgeon access to the coronary arteriesThe two coronary arteries, the right and the left, form the blood network that supplies the heart with oxygen and nutrients. They are located directly on the surface of the heart and branch into smaller vessels that that need repair.
Identifying the Arteries to Repair
The surgeon identifies the segments of blocked arteries that require bypassing.
Next, the vessels (veins or arteries) that will be used to bypass the obstructions are harvested.
Preparing the Grafts for the Bypasses
In most cases, a vein from the leg (often the saphenous vein) and the left internal mammary artery, located inside the chest, are used to create the bypasses over the blocked arteries.
In some cases, other vessels may be selected, such as:
- A vein from the thigh or the back of the leg
- The right internal mammary artery (from the right side of the chest)
- Or the radial artery, located in the forearm (where the pulseThe pulse is the sensation of beating that one feels by applying slight pressure on an artery, usually at the wrist or neck. It corresponds to the blood flow pulsated by the heart through the arteries with is usually taken)
Two Surgical Techniques
Today, bypass surgery can be performed using two main approaches:
- Either with the heart temporarily stopped, supported by a heart-lung machine
- Or with the heart still beating, a more recent method called “off-pump” or beating-heart surgery, used depending on the situation and the patient’s condition
Stopped-Heart Technique
The first method involves temporarily stopping the heart, which requires the use of a heart-lung machine, also called cardiopulmonary bypass.
To do this, the heart is cooled to reduce its oxygen needs—much like putting it into hibernation, like a bear in winter.
It then stops beating.
During this time, bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood is diverted outside the body using tubes connected to the machine.
This pump takes over the role of the heart and lungs: it oxygenates the bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood and sends it back into the circulation by injecting it into the aorta, so that all organs continue to receive bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood during the surgery.
Beating-Heart Technique
The second approach allows the bypasses to be performed without stopping the heart.
The heart continues to beat naturally throughout the procedure.
In this technique, the heart-lung machine is not used.
However, since the heart is constantly moving, a special stabilizing device is used to locally steady the area where the bypass is to be performed.
This allows the surgeon to work with precision, despite the heart’s motion.
Tiny Tubes Sewn with Very Fine Thread
To connect the new vessels to the heart’s arteries, the surgeon must perform extremely delicate stitching.
They wear magnifying lenses attached to their glasses or use a surgical microscope to better see the fine details.
The thread used is extremely thin, as fine as a human hair, because the vessels are very small in diameter.
Checking That the Bypasses Are Working Properly
Once the bypasses are complete, the surgeon uses a measuring device to check that blood is flowing properly through the new grafts.
This ensures that the sutures are secure and that each bypass is functioning as intended.
Warming the Heart and Restarting Its Activity
When the surgery is performed with cardiopulmonary bypass, the heart is cooled to allow it to rest.
At the end of the procedure, it is gradually rewarmed to about 22°C (72°F).
The heart usually starts beating on its own again, under the close supervision of the surgical team, assisted by the heart-lung pump technicians.
A Temporary Pacemaker—Just in Case
Before closing the chest, the surgeon places small pacing wires on the heart.
These wires are connected to a temporary pacemaker, which can be used if the heart rate slows down after surgery.
At the same time, chest drains are placed around the heart and lungs to remove any air or bloodBlood is composed of red blood cells, white blood cells, platelets, and plasma. Red blood cells are responsible for transporting oxygen and carbon dioxide. White blood cells make up our immune defense system. Platelets contribute to blood that may accumulate.
And Then We Close Everything Up
To close the chest, the sternum is secured with steel wires, like an internal zipper.
The skin is then closed with dissolvable stitches (which fade on their own), or in some cases, with small metal staples.
Recovery in the hospital
Monitoring in the Intensive Care Unit
Once the surgery is complete, the patient is transferred to a specialized bed and brought to the intensive care unit (ICU).
They are still under the effects of anesthesia and will wake up gradually, usually a few hours later, under the close supervision of the medical team.
Recovery Begins
The first moments after surgery are often accompanied by a sense of relief, and sometimes even mild euphoria.
The patient becomes aware that the operation is behind them, and the joy of being alive outweighs the fatigue.
However, the next day may be more difficult. The body reacts to the procedure, energy levels drop, and a temporary low mood or sadness may set in.
This is completely normal.
Fortunately, these feelings are temporary.
Recovery progresses steadily, vitality returns, and the patient gradually regains confidence in their strength and ability to heal.
Postoperative Guidelines
After heart surgery, the recovery period begins in the hospital and requires active cooperation between the care team and the patient.
Several aspects are essential to speed up recovery, prevent complications, and prepare for discharge—whether returning home or transitioning to a rehabilitation center.
- Rest and Gradual Return to Movement
Rest is necessary during the first hours after surgery. Then, progressive mobilization—initially supervised, then autonomous when safe—is strongly encouraged.
Getting up, walking, and moving regularly helps prevent lung and circulation complications, such as blood clots.
- Pain Management
Effective pain control is crucial. It supports deep breathing, movement, and overall comfort.
Medications are provided as needed, following a plan tailored to each patient.
- Breathing Exercises
After heart surgery, breathing exercises are recommended to help fully expand the lungs and support a good recovery.
These exercises, often done with an incentive spirometer, should be performed several times a day. They help prevent:
- Airway congestion
- Atelectasis (partial lung collapse)
- Lung infections
Coughing also plays a key role in clearing the airways.
However, some patients hold back from coughing due to fear of pain around the chest incision.
In this case, supporting the chest with a pillow while coughing is a simple and helpful way to reduce discomfort and allow for effective coughing.
To read: Post-Surgery Breathing Physiotherapy
- Wound Monitoring
The surgical site(s) must be checked regularly to detect any sign of infection or other abnormalities.
Wound care is performed following strict hygiene protocols.
- Precautions After Sternotomy
When the chest has been opened (sternotomy), specific precautions are provided to avoid movements or efforts that could disturb the healing of the sternum.
- Ongoing Health Monitoring
The medical staff closely monitors your recovery to detect any sign of problems, such as arrhythmias, infections, or overall instability in your condition.
Average Hospital Stay
The length of hospital stay after bypass surgery varies from person to person.
Each patient recovers at their own pace, depending on their overall health, age, the complexity of the surgery, and whether complications occur.
That said, in most cases, hospitalization lasts less than a week.
Some patients are discharged after just 4 or 5 days, once their condition is stable and the initial recovery goals have been met.
To read: At Home After Heart Surgery
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