Definition and Overview
The carotid artery, which is the main artery that delivers blood to the face and brain, can sometimes become partially or totally blocked due to plaque accumulation. This condition reduces the amount of blood supplied to the brain and may thus cause a stroke.
The condition is initially treated to remove blockage by performing procedures such as angioplasty with stent placement and endarterectomy, which aim to remove plaque that has accumulated in the artery and to provide support to keep the artery from collapsing in the future (stenting). However, in some cases, another procedure is performed to rechannel blood flow through other vessels.
Who Should Undergo and Expected Results
The process of rechanneling an artery and other procedures used to treat blocked or narrowed blood vessels are performed on patients whose blood vessels have become clogged due to plaque buildup. Plaque tends to build up, especially in the medium and large arteries, depending on the patient's age, lifestyle, and hereditary factors. Plaque buildup results in a disorder called atherosclerosis, in which the arteries harden. When this affects the carotid arteries, it results in another condition called carotid stenosis or carotid artery disease, which may cause carotid artery pain and other symptoms.
Prior to performing a rechanneling procedure, the doctor will first perform a series of tests to determine the extent to which the artery is blocked. If as much as 70% of the artery is blocked, then the doctor can prescribe surgery.
However, this procedure may not be safe for all patients. Those who suffer from temporary injury to their brain or have suffered a stroke are not advised to undergo the procedure.
After rechanneling the artery, blood flow to the brain is expected to improve. This can reduce the patient’s risk of suffering from a stroke. According to the National Stroke Association, successfully rechanneled arteries reduce the risk of stroke by up to 70% among patients with existing blockage in their arteries and up to 80% among people who have had a stroke or symptoms of it before. It also reduces the risk of stroke by 50% among people who have carotid artery stenosis, or blockage of 66% up to 90% in their carotid arteries.
Patients who have carotid artery blockage below 50%, however, are not good candidates for the rechanneling of the artery. The benefit for such patients is much lower and does not fully warrant the use of the procedure with all the risks involved. Thus, the procedure is reserved mostly for high-risk individuals.
How is the Procedure Performed?
Prior to the rechanneling of the artery, the patient will be asked to stop smoking. Any medication that makes it harder for blood to clot should also be stopped; these may include aspirin, ibuprofen, clopidogrel, Naprosyn, and other similar medications. The doctor may also provide certain instructions about what to eat and drink prior to the procedure.
Also, since this procedure has its own risks, patients should inform their doctor about any illness they may have, aside from a blocked carotid artery. These include even a simple cold or flu.
On the scheduled day of the surgery, patients are advised to arrive at the hospital on time for preparations. He or she will be given general anesthesia, which means that the patient will be asleep and completely unable to feel pain all throughout the procedure. However, it is also possible for the procedure to be performed under local anesthesia, in which only the part of the body where the surgery is being performed becomes numb. This is usually accompanied by sedatives or medicines that help the patient relax during the procedure.
While the procedure is being performed, the patient is asked to lie on his side on the operating table, making sure to expose the side where the blocked carotid artery is located. The procedure begins with the surgeon making a large cut or incision on the neck, just over the said artery. He then inserts a flexible catheter into the artery, allowing blood to flow through it and around the blockage. With blood flow diverted, the surgeon can start rechanneling the artery to restore normal blood flow to the brain. All throughout the procedure, the patient’s cardiovascular activities are closely monitored.
After the procedure, the surgeon closes the incision. The whole procedure may take about 2 hours. It is then followed by some tests to confirm whether blood flow to the brain is normal. Patients are also placed under close monitoring for a few hours, possibly overnight if the procedure is done later in the day, to check for signs of bleeding, stroke, or poor blood flow. However, if the procedure is done earlier in the day, the patient may be able to go home the same day.
Possible Risks and Complications
There are serious risks involved during a rechanneling of any artery in the neck. These complications may arise during or after the procedure. These include:
High blood pressure
Bleeding inside the brain
Restenosis, or when plaque builds up in the carotid artery again
The following are symptoms associated with nerve injury:
Poor saliva management
Compromised tongue movement
Restenosis can occur between five months and thirteen years following a rechanneling of the artery.
A person’s risk of suffering from these complications is affected by his age and overall health. However, the surgeon’s skill and experience level may also play a role.
The overall risk to patients should be initially examined prior to the procedure to ensure that the surgery is safe for the patient.
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Lovrencic-Huzjan A, Rundek T, Katsnelson M. “Recommendations for management of patients with carotid stenosis.” Stroke Research and Treatment vol. 2012. https://www.hindawi.com/journals/srt/2012/175869/
Johnson BF, Verlato F, Bergelin RO, Primozich JF, Strandness DE Jr. “Clinical outcome in patients with mild and moderate carotid artery stenosis.” Journal of Vascular Surgery. http://www.jvascsurg.org/article/S0741-5214(95)70250-4/abstract