What are the symptoms and treatment options for carotid stenosis?

Symptoms and Treatment of Carotid Stenosis

Carotid stenosis can present with a spectrum of symptoms ranging from asymptomatic to severe neurological deficits, with treatment options including medical management, carotid endarterectomy, or carotid stenting depending on symptom status and stenosis severity.

Symptoms of Carotid Stenosis

Symptomatic Carotid Stenosis

Patients with carotid stenosis may present with various neurological symptoms due to cerebral ischemia:

1. Focal Neurological Deficits:

   • Motor deficits: Isolated paresis of hand, arm, or face (less commonly the leg) 1
   • Sensory deficits: Numbness or tingling on one side of the body 1
   • Language disturbances: Aphasia (if left hemisphere affected) 1
   • Cognitive symptoms: Hemineglect (predominantly in right hemisphere lesions) 1
   • Visual field defects: Hemianopsia 1

2. Ocular Symptoms:

   • Amaurosis fugax (temporary monocular blindness) 1
   • Permanent partial or total blindness in the ipsilateral eye 1
   • Retinal emboli (may be detected during examination) 1

3. Transient Ischemic Attack (TIA):

   • Focal neurologic deficits lasting <24 hours (typically <60 minutes) 1
   • High risk of subsequent stroke (up to 20% in first 3 months in older studies, ~6% in first year in recent registries) 1

4. Unusual Presentations:

   • "Limb-shaking TIA" due to hemodynamic impairment 1
   • "Stuttering stroke" with symptom progression over hours to days 1

Asymptomatic Carotid Stenosis

By definition, asymptomatic carotid stenosis has no associated neurological symptoms. However:

• Patients may have silent brain infarction on imaging 1
• Retinal emboli may be detected incidentally 1
• Typically defined as absence of ipsilateral symptoms within the previous 6 months 1

Diagnostic Evaluation

1. Initial Imaging:

   • Duplex ultrasonography (DUS) is recommended as first-line examination 1, 2
   • Measures peak systolic velocity in the internal carotid artery to determine stenosis severity 1

2. Additional Imaging:

   • CT angiography (CTA) and/or MR angiography (MRA) to evaluate extent and severity 1, 3
   • Brain imaging (CT or MRI) to assess for silent infarcts or other pathology 1

3. Risk Stratification:

   • Plaque morphology assessment (echolucency, ulceration, inflammation) 3
   • Transcranial Doppler to detect microemboli 4

Treatment Approaches

Medical Management

Medical therapy is the cornerstone of treatment for all patients with carotid stenosis:

1. Antiplatelet Therapy:

   • Low-dose aspirin or clopidogrel (in case of aspirin intolerance) 1
   • For recent minor stroke or TIA, short-term dual antiplatelet therapy may be reasonable 1

2. Risk Factor Modification:

   • Statin therapy for lipid management 3
   • Blood pressure control, preferably with ACE inhibitors 3
   • Smoking cessation 2
   • Diabetes management 2
   • Diet modification and regular physical activity 1

Surgical Management for Symptomatic Carotid Stenosis

For symptomatic patients with 50-99% stenosis, carotid endarterectomy (CEA) is strongly recommended, ideally performed within 14 days of symptom onset 1.

Key considerations:

• CEA should be performed by experienced surgeons with audited perioperative stroke and death rates <6-7% 1
• Greatest benefit is seen in men, patients ≥75 years, and those treated within two weeks of symptoms 1
• CEA is generally more appropriate than stenting for patients over 70 years 1

Surgical Management for Asymptomatic Carotid Stenosis

For asymptomatic carotid stenosis (50-99%), the approach is more nuanced:

• Medical therapy alone has improved significantly, with annual stroke risk now approximately 1% 4, 3
• CEA may be considered in selected patients with high-grade (>60%) asymptomatic stenosis 1, 3
• Patients with specific high-risk features (microemboli on transcranial Doppler) may benefit more from intervention 4

Carotid Artery Stenting (CAS)

CAS may be considered in specific situations:

• Patients who are not candidates for CEA due to technical, anatomical, or medical reasons 1
• High surgical risk patients (severe coronary disease, contralateral occlusion) 1
• Should be performed by experienced interventionists with audited results 1

Common Pitfalls and Caveats

1. Timing of Intervention:

   • Delaying intervention for symptomatic stenosis beyond 2 weeks significantly reduces benefit 1
   • Urgent evaluation by a clinician with stroke expertise is essential for symptomatic patients 1

2. Patient Selection:

   • Women with asymptomatic stenosis may derive less benefit from CEA than men 5
   • The benefit of intervention for asymptomatic stenosis has diminished with improved medical therapy 4, 3

3. Perioperative Risk:

   • Perioperative stroke or death risk must be <6% for symptomatic and <3% for asymptomatic patients to maintain benefit 1
   • CAS carries higher perioperative risk than CEA, particularly in older patients 1

4. Measurement Accuracy:

   • Inaccurate measurement of stenosis severity can lead to inappropriate treatment decisions 5
   • CTA is recommended to guide surgical decision-making 1

In conclusion, the management of carotid stenosis requires careful consideration of symptom status, stenosis severity, patient characteristics, and surgical risk. While symptomatic carotid stenosis generally warrants prompt intervention, asymptomatic disease is increasingly managed medically with selective intervention for high-risk features.