Carotid artery disease is responsible for 10-20% of strokes. The disease is caused due to narrowing of the carotid arteries due to the deposition of cholesterol in the vessel walls. Damage to the wall may cause further narrowing by the formation of blood clots. This deposition can be removed surgically by carotid endarterectomy or it can be mitigated by the placement of a stent.
- Carotid endarterectomy: Endarterectomy refers to the removal of material inside the vessel. This is a surgical procedure done under general anesthesia. Your surgeon will make an incision in your neck and reach the affected carotid artery. The artery is then opened and the cholesterol deposit and the blood clot are scooped out after which the artery is closed. A drain may be left in place in some cases.
- Carotid artery stenting: In this procedure, a thin tube (catheter) is introduced into the artery in your groin. Under x-ray monitoring, the catheter reaches the narrowed artery. Once the catheter is in its place its tip is expanded for a few seconds to widen the narrowed artery. A stent is then introduced to ensure that the artery remains open. Some stents might also have drugs in them that prevent the narrowing of the artery in the future.
Indications for Carotid Surgery and Stents
- Carotid endarterectomy (CEA): surgery causes substantial benefit in individuals with 70% narrowing in the carotid artery. Studies have shown that this procedure has the greatest benefits when performed within 2 weeks of the onset of symptoms of TIA or stroke. Hence it is indicated in individuals with recent symptoms and a high grade of narrowing. There isn’t enough evidence for recommending the surgery to asymptomatic patients without a high grade of narrowing.
- Carotid endarterectomy is specially suggested in people with tortuous blood vessels which might make access to the carotid artery difficult with a catheter.
- Carotid artery stenting (CAS): studies have shown that in most cases CAS and CEA are equally efficacious. CAS has the advantage of being less invasive. This procedure is preferred when the narrowing in the artery is nearer to the base of the skull. Individuals with a contraindication for surgical procedures are advised to have CAS instead.
Causes of carotid stenosis
Carotid artery stenosis can be caused by various factors, some of which can be modified to reduce the risk of developing this condition. These factors include
- A Sedentary Lifestyle
- High Blood Pressure
- High Cholesterol
While some of these factors can compound others, they all increase the likelihood of developing carotid artery stenosis over time.
Symptoms of carotid stenosis
Symptoms of carotid artery stenosis typically arise when a stroke occurs, often caused by plaque or platelets that travel to the brain and cut off its blood supply. This can lead to ischemic stroke, which causes brain cells to die when the blockage is permanent. The symptoms of a TIA or stroke can include
- Drooping one side of the face
- Slurred speech or difficulty communicating
- Vision loss in one eye
- Loss of feeling or muscle strength on one side of the body.
If carotid artery stenosis has not yet caused a stroke, there may be no noticeable symptoms.
How is carotid stenosis diagnosed?
Carotid artery stenosis is typically detected following the onset of stroke symptoms, which may prompt a thorough examination by a healthcare professional to identify any blockages that could be contributing to the condition. Additionally, a healthcare provider may use a stethoscope to detect an unusual sound, known as a bruit or murmur, during a neck exam, which can lead to a diagnosis of carotid artery stenosis. To confirm this diagnosis and gather more information about the size and location of the blockage, various tests may be conducted by healthcare providers. These tests can include:
- Computed tomography angiography (CTA)
- Cerebral angiography
- Magnetic resonance angiography (MRA)
Treatment of carotid stenosis
The treatment for carotid artery stenosis involves the following:
- Halting the progression of the disease by making lifestyle modifications such as adopting a healthy diet, exercising regularly, and quitting smoking
- Taking a daily dose of aspirin along with medications that lower blood pressure and cholesterol
In more severe cases or cases that cause symptoms of TIA or stroke, surgical procedures may be required such as:
- Carotid endarterectomy – involves the removal of plaque from the carotid artery through an incision
- Carotid artery stenting – involves the placement of a stent through a needle puncture, opening up the artery to its proper size and trapping the plaque away from the blood flow between the stent and the wall
The suitability of these procedures is determined by a vascular surgeon or specialist and is only recommended when the risk of severe stenosis or stroke is greater than the risk of the procedure. Not all cases of carotid stenosis require surgical or interventional treatment, as these procedures themselves come with risks.