What is a carotid endarterectomy?
Carotid endarterectomy is a surgical procedure to unblock a carotid artery. The carotid arteries are the main blood vessels that supply the head and neck.
Carotid endarterectomies are carried out when one or both carotid arteries have become narrowed due to a build-up of fatty deposits (plaque). This is known as carotid artery disease or carotid artery stenosis.
If a narrowed carotid artery is left untreated, the blood flow to the brain may be affected, resulting in a:
- stroke - a serious medical condition that can cause brain damage or death
- transient ischaemic attack (TIA) - sometimes known as a "mini-stroke", a TIA is similar to a stroke but the signs and symptoms are temporary and usually disappear within 24 hours
Carotid endarterectomy can significantly reduce the risk of a stroke in people with severely narrowed carotid arteries. In people who have previously had a stroke or a TIA, their risk of having another stroke or TIA within the next three years is reduced by a third after surgery.
Read more about when carotid endarterectomy is needed.
About the procedure
The carotid endarterectomy procedure can be carried out using local anaesthetic or general anaesthetic. Local anaesthetic is often preferred because it means your surgeon can monitor the response of your brain to the changes in blood flow during surgery.
During the procedure, a 7-10cm (2.5-4 inch) incision will be made between the corner of your jaw and your breastbone. A small incision is then made along the narrowed section of artery and the fatty deposits that have built up there are removed.
The artery is then closed with stitches or a patch and your skin is sealed with stitches.
What happens after the procedure
You will usually be moved to the recovery area of the operating theatre after a carotid endarterectomy so your health can be monitored. Most people are well enough to go home within about 48 hours of the procedure.
In most cases, the only problems experienced after the operation are temporary numbness or discomfort in the neck. However, there is a small risk of serious complications due to the procedure - including stroke and death.
Nevertheless, this risk is much lower than in people with carotid artery disease who have not had the operation.
Are there any alternatives?
A carotid endarterectomy is the main treatment for narrowing of the carotid arteries, but sometimes an alternative procedure called carotid artery stent placement may be available.
This is a less invasive procedure than a carotid endarterectomy because it does not involve an incision being made in the neck. Instead, a thin, flexible tube is guided to the carotid artery through a small cut in the groin. A mesh cylinder (stent) is then placed into the narrowed section of artery to widen it and allow blood to flow through it more easily.
Read more about carotid artery stent placement.
Carotid endarterectomy diagnosis
A carotid endarterectomy may be needed if one or both of your carotid arteries become narrowed due to a build-up of fatty deposits (plaque).
Why carotid artery disease develops
Normal, healthy arteries are elastic and smooth on the inside, allowing blood to easily flow through them. As a person gets older, plaque can build up inside the arteries, making them narrower and stiffer. This process is called atherosclerosis.
As well as ageing, there are several other factors that can contribute to a build-up of plaque, including:
- a high-fat diet
- high blood pressure (hypertension)
- diabetes - a lifelong condition that causes a person's blood sugar level to become too high
Read more about the causes of atherosclerosis.
Carotid artery disease and stroke
There are two ways that a stroke or TIA could occur if the flow of blood through your carotid arteries becomes blocked or restricted. These are described below:
- if the carotid artery is completely blocked, limiting the blood supply to your brain - this type of stroke is known as an ischaemic stroke
- if a blood clot forms on the roughened surface of the carotid artery and breaks off it may block one or more arteries in the brain - this type of stroke is known as an embolic stroke
Diagnosing carotid artery disease
Carotid artery disease is usually diagnosed if a person has the symptoms of a stroke or TIA, such as the face drooping on one side, numbness or weakness in the arms or legs, speech problems or loss of vision in one eye.
However, occasionally narrowing of the carotid arteries may be diagnosed if you are having tests for another reason and the doctor testing you notices that your arteries are narrowed. This is called an asymptomatic carotid stenosis.
If you have recently had a stroke or a TIA, you will be referred for some brain imaging tests. This will allow the blood supply to your brain to be checked and any narrowing in your carotid arteries to be diagnosed.
Several tests can be used to examine your carotid arteries and find out how much plaque has built up inside them. These include:
- Duplex ultrasound scan - sound waves are used to produce an image of your blood vessels and measure the blood flow through them. It can also show how narrow your blood vessels are.
- Computerised tomography (CT) scan -a series of X-rays are taken at slightly different angles. A computer assembles the images to create a detailed picture of the inside of your body.
- Computed tomographic angiogram (CTA) - a special dye is injected into a vein and a CT machine is used to take X-rays to build up a picture of your neck arteries.
- Magnetic resonance angiography (MRA) - a magnetic field and radio waves are used to produce images of your arteries and the blood flow within them.
An ultrasound scan is usually used first to check if there is any narrowing in your arteries and to determine whether it is severe enough for you to benefit from having surgery.
If your arteries are narrowed, you may need to have further tests to confirm the diagnosis, such as a CTA or MRA.
Grading narrowed arteries
If tests indicate that your carotid arteries are narrowed, the severity of the narrowing (stenosis) will be graded to determine if you need surgery.
In the UK, the most common grading system that is used is the NASCET scale (North American Symptomatic Carotid Endarterectomy Trial). The scale has three categories:
- minor - 0%-49% narrowed
- moderate - 50%-69% narrowed
- severe - 70%-99% blocked
When surgery is recommended
You should be assessed within a week of the start of your stroke or TIA symptoms, and the operation will ideally be carried out within two weeks of the start of your symptoms.
It is absolutely crucial that you seek medical advice as soon as possible if you develop symptoms of a stroke or TIA, as surgery has the best chance of preventing a further stroke if it is performed as soon as possible.
Surgery will sometimes be recommended if you have not previously had a stroke or a TIA, but you are found to have severe stenosis.
Surgery will not be recommended if you have minor stenosis (less than 50%). This is because surgery has the most benefit for people with moderate and severe stenosis (over 50%), with the maximum benefit being seen in those with severe stenosis (70%-99%).
A carotid endarterectomy is not of any benefit in people with a complete blockage of their carotid artery.
Carotid endarterectomy risks
As with all types of surgery, there are risks associated with having a carotid endarterectomy.
The two main risks are:
- stroke - the risk of stroke is around 2%, although this may be higher in people who have had a stroke before the operation
- death - there is a less than 1% risk of death, which can occur due to complications such as a stroke or heart attack
Most strokes that occur after carotid endarterectomy are caused by an artery in the brain becoming blocked during the early post-operative period, or because there is some bleeding into the brain tissue. Your surgical and anaesthetic team will do all they can to prevent this.
As well as stroke and death, there is a small chance of developing other complications after having a carotid endarterectomy. These include:
- pain or numbness at the wound site - this is temporary and can be treated with painkillers
- bleeding at the site of the wound
- wound infection - the wound where the incision was made can get infected; this affects less than 1% of people and is easily treated with antibiotics
- nerve damage - this can cause a hoarse voice and weakness or numbness on the side of your face; it affects around 4% of people but is usually temporary and disappears within a month narrowing of carotid artery again - this is called restenosis; further surgery is required in about 2-4% of people
Your surgeon should explain the risks that are associated with a carotid endarterectomy before you have the procedure. Ask them to clarify anything you're not sure about and answer any concerns you have.
Factors that increase your risk of experiencing complications due to a carotid endarterectomy include:
- your age - the risk increases as you get older
- whether you smoke
- having previously had stroke or transient ischaemic attack (TIA) - the risk will depend on the severity of the stroke or TIA, how well you recovered and how recently it occurred
- whether you have a blockage in your other carotid artery as well
- whether you have other health conditions, such as cancer, heart disease, high blood pressure (hypertension) or diabetes
Carotid endarterectomy alternatives
Carotid endarterectomy is the main treatment for narrowing of the carotid arteries because it is very effective. However, there is also an alternative procedure called carotid artery stent placement, or "stenting".
Carotid artery stent placement
Carotid artery stent placement is less invasive than a carotid endarterectomy because it does not involve an incision being made in the neck.
Stenting is carried out under local anaesthetic and involves a narrow, flexible tube called a catheter being inserted into an artery in your groin. It is then threaded up into the carotid artery using X-rays to guide it into place.
At the end of the catheter there is a small balloon which is inflated to around 5mm at the site of the narrowed artery. A small mesh cylinder called a stent will then be inserted into the artery. The balloon will be deflated and removed, leaving the stent in place to keep the artery open and allow blood to flow through it.
After the procedure, you will need to lie flat and keep still for about an hour to prevent any bleeding from the artery. You will also need to stay in hospital overnight and will be able to return home the next day.
Like carotid endarterectomy, there are some risks associated with stenting. The risks of having another stroke or dying are the same for both procedures. As with carotid endarterectomy, stenting will therefore only be recommended if your carotid arteries become severely narrowed.
The National Institute for Health and Care Excellence (NICE) has confirmed that stenting is a safe procedure and has good short-term results, although the long-term effectiveness of stenting is not yet known. NICE advises that, provided the risks of stenting are judged similar to those after surgery, it is safe to offer this alternative.
Before being admitted for surgery, you will have a careful pre-operative assessment.
If a carotid endarterectomy has been arranged in advance, this assessment will usually be carried out in a hospital pre-assessment clinic a few days before you are due to have the procedure. In some cases, you will be asked to attend the pre-assessment clinic on the day the operation is scheduled.
Alternatively, you may be seen in a specialist clinic if you have recently had a stroke or transient ischaemic attack (TIA). At these clinics, tests to check the health of your arteries will be carried out and you may be admitted for surgery immediately if your carotid arteries are found to be severely narrowed.
At a pre-admission clinic you will have a physical examination and be asked about your medical history. Any further tests or investigations that are needed will also be carried out at this time.
The pre-admission clinic is a good opportunity for you to ask your treatment team about the procedure, although you can discuss any concerns that you have at any time.
If you are taking any medication (prescribed or otherwise), it would be useful to bring it with you to the pre-admission clinic so the details can be noted.
You will be asked whether you've had anaesthetic (painkilling medication) in the past and whether you experienced any problems or side effects, such as feeling sick.
You will be also asked whether you are allergic to anything, to avoid a reaction to any medication that you may need during your treatment.
Your treatment team will ask you about your teeth, including whether you wear dentures, have caps or a plate. This is because during the operation you may need to have a tube put down your throat to help you breathe and loose teeth could be dangerous.
Preparing for surgery
Before having a carotid endarterectomy, your surgeon will discuss how you should prepare. They may give you the following advice:
- Stop smoking - smoking will increase your risk of developing a chest infection, it can delay healing and increase your risk of developing a blood clot.
- Watch your weight - if you are overweight, losing weight will be recommended; as strenuous exercise could be dangerous, you will need to do this by dieting; your doctor will be able to advise you about how to lose weight.
- Gentle post-op exercise - being active can help your recovery, but you should not overdo it; your surgeon or doctor can advise you about how much you can do.
- Think positive - a positive mental attitude can help you deal with the stress of surgery and aid your recovery.
Read more about preparing for surgery.
Recovery from a carotid endarterectomy
After a carotid endarterectomy, you will usually be moved to the recovery area of the operating theatre, or in some cases a high dependency unit (HDU).
A HDU is a specialist unit for people who need to be kept under close observation after surgery, usually because they have high blood pressure and need to be closely monitored.
Following surgery, your breathing and heart rate will be monitored to ensure that you are recovering well.
You may have some discomfort in your neck around where the incision was made. This can usually be controlled with painkillers. You may also experience numbness around the wound, which should disappear after a while.
Most people are able to eat and drink a few hours after having surgery. You will usually be able to leave hospital and return home within 48 hours.
The wound on your neck will be closed with stitches. You may have dissolvable stitches, which should disappear after about three weeks. However, you may need to have the stitches removed. Your surgeon will be able to advise you about this.
Your surgeon will also be able to give you advice about caring for your wound. This will usually be a simple matter of keeping it clean using mild soap and warm water.
You may be left with a small scar running from the angle of your jaw to the top of your breastbone. The scar is usually about 7 to 10cm (2.5 to 4 inches) long and will fade to a fine line after two or three months.
Your doctor will be able to advise you about when it is safe for you to drive following surgery. You will be able to drive when you can safely carry out an emergency stop. For most people, this is between two to three weeks after the operation.
If you have had a stroke or transient ischaemic attack (TIA), you will not be allowed to drive for a month afterwards. If you have fully recovered, you do not need to inform the DVLA unless you drive a lorry or a bus for a living.
Work and exercise
Most people are able to return to work three to four weeks after having a carotid endarterectomy. Your surgeon or doctor will be able to advise you further about returning to work.
You may be advised to limit physical activity for a few weeks after having surgery. This includes manual labour and playing sports. If your job involves manual labour, you should only perform light duties until you have fully recovered.
A carotid endarterectomy will either be carried out under general or local anaesthesia.
Anaesthetic is painkilling medication that allows surgery to take place without a patient feeling pain or discomfort.
If you have a general anaesthetic, you will be asleep throughout the procedure. If you have a local anaesthetic, you will remain conscious but the area on your neck will be numbed so you cannot feel any pain.
Studies comparing the results of carotid endarterectomies found no difference between the two types of anaesthetic. Therefore, it will be up to you, your surgeon and your anaesthetist (specialist in anaesthesia) to decide which type of anaesthetic to use.
Your surgeon may prefer to use local anaesthetic so that you remain conscious during the operation. This will allow them to monitor your brain’s reaction to the decreased blood supply throughout the procedure.
A carotid endarterectomy usually takes one to two hours to perform. If both of your carotid arteries need to be unblocked, two separate procedures will be carried out. One side will be done first and the second side will be done a few weeks later.
Once you are asleep, or the area has been numbed, your neck will be cleaned with antiseptic to stop bacteria getting into the wound. If necessary, the area may also be shaved. A small incision will then be made to allow the surgeon to access your carotid artery.
During the procedure, your surgeon will decide whether to use a temporary shunt to maintain adequate blood flow to the brain. A shunt is a small plastic tube that can be used to divert blood around the section of the carotid artery being operated on.
The decision to use a shunt is based on surgeon preference and the results of brain blood flow monitoring during the operation. A shunt will not usually be used if the carotid artery on the other side of the neck is supplying the brain with enough blood.
When the surgeon has access to the carotid artery, the artery is clamped to stop blood flowing through it and an opening made across the length of the narrowing. If a shunt is to be used, it will be inserted now.
The surgeon will then remove the inner lining of the narrowed section of artery, along with any fatty deposits (plaque) that have built up.
Once the narrowing has been removed, the opening in the artery will then either be closed with stitches or a special patch. The majority of surgeons in the UK use a patch but the choice is down to surgeon preference.
Your surgeon will then check for any bleeding. After any bleeding has stopped, the incision in your neck will be closed. A small tube (drain) may be left in the wound to drain away any blood that might build up after the operation. The tube will usually be removed the following day.
After the procedure
When the operation is finished, you will usually be moved to the recovery area of the operating theatre, where your health can be monitored to ensure you are recovering well.
Read more about recovering from a carotid endarterectomy.