Coronary Bypass Graft (CABG) is a surgical operation employed to treat partially or completely blocked coronary arteries that supply oxygen-rich blood to the heart muscle.
Going around or “bypassing” the blocked artery to enhance the flow of oxygen-rich blood to the heart achieves this.
The surgery may be done as an emergency solution following a heart attack, or on an elective basis in cases where conservative treatment methods have failed to alleviate symptoms of coronary artery disease such as chest pain, and shortness of breath.
The coronary arteries transport blood to the heart muscle. The moment these arteries become narrowed or blocked, blood flow to the heart is decreased. This decrease in blood flow diminishes oxygen supply to the myocardium (heart muscle).
Every time the myocardium is deprived of oxygen it sends out signs in the form of angina (chest pain), shortness of breath, or even a heart attack.
Coronary Artery Disease (CAD)
Coronary Artery Disease is generally a result of a condition called Atherosclerosis. In this condition, a waxy substance called plaque progressively accumulates on the walls of the coronary arteries.
Eventually, the plaque thickens, hardens, and narrows the coronary arteries compromising blood flow.
Symptoms of CAD include chest pain (angina), shortness of breath, and, if left untreated, heart attack.
Refer to the diagram to see the difference between a normal artery and a narrowed artery caused by Atherosclerosis.
Coronary Artery Disease Risk Factors
Risk factors for Coronary Artery Disease include the following
- Family history
- Hypertension (high blood pressure)
- High cholesterol or other fat levels in blood
- Inactive lifestyle - obesity/overweight/lack of exercise
- Diabetes (high blood sugar)
- Cigarette smoking
- Non-compliance with medicines to treat hypertension and high cholesterol
Signs and Symptoms
Coronary Artery Disease is the most common cause of Angina and Heart Attack.
Chest pain is the most common complaint in heart attack. Unlike angina, pain does not subside on resting. However, the symptoms may be different.
- Fullness, uncomfortable pressure, squeeze in the middle of the chest
- Tightness, burning or heavy weight over your chest
- Pain may radiate to your shoulders, neck, arms, upper abdomen, back or jaw.
20% of the patients with heart attack have no pain. This is seen in diabetics, high blood pressure, and elderly patients.
Heart attack is a medical emergency and if you suspect symptoms of heart attack, you should call for an ambulance or seek immediate medical help.
A cardiologist should evaluate all heart conditions for proper diagnosis and treatment.
Your cardiologist will perform the following:
- Medical history
- Physical examination
Diagnostics Studies may include:
- Blood tests
- (EKG or ECG) Electrocardiogram
- Nuclear Heart Scans
Conservative Treatment Options for CAD
Healthy life choices will improve your overall health and your heart health and can help you slow the progression of your heart disease.
Some heart healthy choices include:
- Healthy Diet Choices
- Don't Smoke
- Weight Loss
- Diabetes Control
Along with life style modifications, medications may be needed to control symptoms and improve the heart health. Your cardiologist may prescribe more than one medication.
What Is Coronary Artery Bypass Graft
Coronary Artery Bypass Graft, also called CABG, is a surgery used to treat narrowed or blocked arteries that supply blood to the heart.
This is accomplished by going around or "bypassing" the blocked artery with a healthy vessel called a "graft" that is taken from the leg, arm or chest. The graft will now carry the blood around the blockage to improve the blood flow to the heart.
The operation usually takes 4 - 6 hours but may be longer depending on the number of bypass to be done.
"Open Heart Surgery" is a common name referring to the traditional method of performing CABG surgery. Many lay people believe the heart is "opened up" in "open heart surgery". However, this is not the case. The name refers to the fact that the surgery is performed through a large, open, chest incision. The surgery is actually performed on the vessels on the outside of the heart.
How is it Done?
The goal of Coronary Artery Bypass Graft surgery is:
- To relieve symptoms of CAD
- Improve blood flow to the heart
- To lengthen the patient's life
During a CABG, the patient is placed lying on their back on the operating table. The chest and graft area are shaved and scrubbed with antiseptic. You will be given a general anesthetic so you will be asleep and not feel any pain.
Your surgeon will make along incision down the middle of your chest bone (sternum). Special instruments called retractors are used to spread the ribs apart so the surgeon can access the heart.
At the same time, another surgeon will "harvest" (remove) a vessel from either your arm (radial artery) or leg (long saphenous vein) to be used as the graft. This may be done through a large "open" incision or endoscopically through a much smaller incision.
Your surgeon may choose to use an artery in the chest called the internal thoracic artery. In this case, you will not have a "graft site" incision on your arm or leg unless you are having multiple bypasses performed.
You will usually be given medicine to stop the heart so your surgeon can perform surgery while the heart is still.
If your heart is stopped your blood will be redirected to a machine called a heart lung machine. This is referred to as cardiopulmonary bypass. This machine does the work of your heart and lungs while your heart is stopped by adding oxygen to your blood and keeping your circulation moving.
If a leg or arm graft is used the surgeon then attaches one end of the graft with fine sutures to the Aorta.
The other end of the graft is then attached to the coronary artery beyond the blockage. This enables the blood to "bypass" the blockage and flow freely to the heart.
If the internal thoracic artery is used, your surgeon will redirect the artery by detaching one end of it, and reattaching it below the blockage on the coronary artery.
Once your surgeon has completed the number of bypasses needed, your heart will be restarted with controlled electrical shocks and you will be removed from the bypass machine.
The surgeon will use wires to reattach the sternum and suture the incision closed, usually with dissolvable sutures.
After CABG surgery you will be taken to the Cardiac Care Unit (CCU) for monitoring.
You will probably have a tube in your throat connected to a respirator for the first day to help you breathe. You will not be able to speak while the tube is in place.
You will have drain tubes in your chest to help drain blood and fluids.
You will likely spend a few days in the hospital. Common post-operative guidelines following Coronary Artery Bypass Surgery include the following:
- You will need someone to drive you home after you are released from the hospital. You should not drive for two weeks after the surgery. If you drive commercially, you may have to wait for a few months. Your surgeon will give you guidelines as to when you may drive based on your situations and your surgeon's preference.
- You will be given instructions on care of your incisions. Normally, you will be able to shower without retractions.
- Expect significant fatigue for the first two weeks after your surgery. This is common and will improve gradually over the next month.
- Your surgeon will give you activity restrictions such as no heavy lifting or strenuous exercise for the first few months to allow the sternum to heal completely.
- You will usually be able to resume sexual activity after a few weeks.
- Talk to your surgeon as to when you may return to work. This time frame will depend on the type of work you perform and your particular situation.
- You will have soreness and bruising around the incision and graft sites for the first month or so. You may hear a clicking sound in the chest while the sternum is healing, especially during movement.
- You will probably have chest pain with sudden movement, coughing, or sneezing. Be assured this is usually musculoskeletal pain and not angina. Your doctor will prescribe pain medications for you to take at home.
- Your doctor will prescribe blood-thinning medicines to prevent blood clots. It is very important that you adhere to your prescribed medications to prevent blood clots from forming.
- It is common to feel depressed after heart surgery. Talk with your doctor, as treatment is available through medication or therapy.
- Sleep disturbances are commonly reported. Again, discuss your concerns with your doctor should you have problems sleeping.
- You will be referred to a cardiac rehabilitation program to educate and assist you with your recovery.
- It is important to know abnormal symptoms to report. Contact your doctor immediately if you have fever, chills, purulent drainage from the incisions, redness, bleeding, irregular heartbeat, chest pain, shortness of breath, weakness, or dizziness.
Risks and Complications
As with any medical procedure there are potential risks involved. The decision to proceed with the procedure is made because the advantages outweigh the potential disadvantages.
It is important that you are informed of these risks before the procedure takes place.
Most patients do not have complications after Coronary Artery Bypass Graft surgery; however, complications can occur and depend on what type of surgery your doctor performs as well as the patient's health status. (i.e. obese, diabetic, smoker, etc.)
Complications can be medical (general) or specific to Coronary Bypass surgery.
Medical complications include those of anesthesia and our general wellbeing. Almost any medical condition can occur so this list is not complete. Complications include:
- Allergic reaction to medications or dye
- Blood loss requiring transfusion with its low risk of disease transmission
- Heart attack, strokes, kidney failure, pneumonia, bladder infections
- Complications from nerve blocks such as infection or nerve damage
- Serious medical problems can lead to ongoing health concerns, prolonged hospitalization, or rarely death.
Specific Complications for Coronary Artery Bypass Graft Include:
- Deep wound infection requiring IV antibiotics and possible surgical debridement.
- Arrhythmia (irregular heart beat)
- Nerve damage causing weakness, neuropathy, or paralysis.
- Blood vessel damage requiring an operation for repair.
- Vein graft occlusion or stenosis
- Recurrent Angina
- Blood clots
- Death (usually less than 3%)
Risk factors that can increase the chance of complications following CABG include:
- History of kidney disease
- Poor cardiac function
- Poor nutrition
- Age (over 75)
- Chronic illness
- Steroid use
- Extensive heart disease
Although every effort is made to educate you on Coronary Artery Bypass Graft surgery and take control, there will be specific information that will not be discussed.
Click here to schedule a talk about any concerns you have about this surgery.
You must not proceed until you are confident that you understand this procedure, particularly, the complications.