From the Guidelines
Carotid artery stenosis often presents asymptomatically and is discovered incidentally during physical examination or imaging studies, but when symptomatic, it typically manifests as transient ischemic attacks (TIAs) or strokes, characterized by sudden weakness or numbness on one side of the body, slurred speech, vision disturbances, or facial drooping. These symptoms occur when narrowed carotid arteries restrict blood flow to the brain or when plaque fragments break off and cause embolic events 1. During physical examination, a carotid bruit (an abnormal whooshing sound) may be heard when auscultating over the carotid artery.
Key Points
- Risk factors include advanced age, smoking, hypertension, diabetes, hyperlipidemia, and family history of cardiovascular disease.
- Diagnosis is confirmed through carotid duplex ultrasonography, CT angiography, or MR angiography, which can determine the degree of stenosis.
- Management depends on symptom status and stenosis severity, ranging from medical therapy (antiplatelet medications like aspirin 81-325mg daily or clopidogrel 75mg daily, statins, blood pressure control) to surgical interventions such as carotid endarterectomy or stenting for severe stenosis (>70%) or symptomatic moderate stenosis (50-69%) 1.
Presentation and Diagnosis
The presentation of carotid artery stenosis can vary, but it is often asymptomatic, and when symptoms do occur, they can be nonspecific. However, some patients may present with symptoms such as:
- Sudden weakness or numbness on one side of the body
- Slurred speech
- Vision disturbances
- Facial drooping These symptoms are typically caused by a reduction in blood flow to the brain or by embolic events caused by plaque fragments breaking off from the narrowed carotid artery.
Management
The management of carotid artery stenosis depends on the severity of the stenosis and the presence of symptoms. According to the Canadian Stroke Best Practice Recommendations, patients with recent transient ischemic attack or non-disabling stroke and ipsilateral 50 to 99 percent symptomatic carotid stenosis should have an evaluation by a clinician with stroke expertise and selected patients should be offered carotid end-arterectomy (revascularization) as soon as possible 1.
Surgical Interventions
Surgical interventions such as carotid endarterectomy or stenting may be necessary for severe stenosis (>70%) or symptomatic moderate stenosis (50-69%). The choice of surgical intervention depends on various factors, including the patient's overall health, the severity of the stenosis, and the presence of other medical conditions. Carotid endarterectomy is generally more appropriate than carotid stenting for patients over age 70 years who are otherwise fit for surgery, as current evidence indicates stenting carries a higher peri-procedural risk of stroke and death in older patients 1.
From the Research
Presentation of Carotid Artery Stenosis
Carotid artery stenosis can present with a wide range of symptoms, from mild to life-threatening. The symptoms may include:
- Blurred vision
- Confusion
- Hemiplegia (paralysis of one side of the body)
- Dysphasia (difficulty speaking)
- Vision loss
- Amaurosis fugax (temporary loss of vision in one eye)
- Transient hemodynamic insufficiency of the retina [ 2 ]
Severity of Symptoms
The presentation of carotid artery stenosis is often insidious, with symptoms exhibiting predominantly at severe stenosis [ 3 ]. The annual risk of stroke in patients with asymptomatic carotid stenosis is less than 5%, while symptomatic carotid stenosis poses a greater risk for recurrent stroke, with estimates as high as 15% per year [ 4 ].
Classification of Carotid Artery Stenosis
Carotid artery stenosis can be classified as symptomatic or asymptomatic disease [ 5 ]. Symptomatic disease is characterized by the presence of neurological symptoms, such as those mentioned above, while asymptomatic disease is characterized by the absence of these symptoms.
Diagnostic and Management Strategies
The diagnosis and management of carotid artery stenosis involve various imaging modalities, including duplex ultrasound (DUS) imaging, and procedures such as carotid endarterectomy (CEA) and carotid stenting [ 3, 6, 5 ]. The choice of management strategy depends on the severity of the stenosis, the presence or absence of symptoms, and other factors, such as the patient's overall health and medical history.