What is the best management approach for a 70-year-old male with blurred vision in the left eye, history of Coronary Artery Disease (CAD), Hypertension (HTN), Type 2 Diabetes Mellitus (T2DM), and significant left Internal Carotid Artery (ICA) stenosis, already on Plavix (clopidogrel) for CAD and stent placement?

Management of Blurred Vision in a Patient with Significant Carotid Stenosis

Urgent Assessment and Diagnosis

For a 70-year-old male with blurred vision in the upper half of the left eye and significant carotid stenosis (70-80% left ICA, 55% right ICA), urgent carotid revascularization with carotid endarterectomy (CEA) is recommended within 14 days to prevent stroke, along with dual antiplatelet therapy for at least 21 days. 1

The patient's presentation with monocular vision loss in the setting of high-grade carotid stenosis should be treated as a transient ischemic attack (TIA) and requires immediate intervention. This symptom pattern strongly suggests retinal ischemia due to emboli from the ipsilateral carotid stenosis.

Immediate Management:

1. Initiate dual antiplatelet therapy (DAPT):

   • Aspirin 81-100 mg daily PLUS
   • Clopidogrel 75 mg daily
   • Continue DAPT for at least 21 days 1, 2
   • After 21 days, continue with single antiplatelet therapy (clopidogrel 75 mg or aspirin) long-term 1

2. Urgent vascular team consultation:

   • Multidisciplinary assessment including vascular surgeon, neurologist, and cardiologist 1
   • Complete neurological assessment to evaluate for other deficits

Revascularization Decision

The patient has symptomatic high-grade (70-80%) left ICA stenosis, which meets criteria for urgent revascularization:

• Carotid endarterectomy (CEA) is recommended for symptomatic 70-99% ICA stenosis within 14 days of symptom onset 1
• The procedure should only be performed at centers with documented perioperative stroke/death risk <6% 1

Factors supporting CEA in this case:

• Symptomatic high-grade stenosis (70-80%) on the left side
• Visual symptoms corresponding to the side of severe stenosis
• Multiple vascular risk factors (HTN, HLD, T2DM, CAD)
• Already on antiplatelet therapy (Plavix) for CAD

Perioperative and Long-term Management

Perioperative care:

1. Continue Plavix (clopidogrel) through the perioperative period
2. Add aspirin if not already taking it
3. Monitor for complications:
   • Hyperperfusion syndrome
   • Wound hematoma
   • Cranial nerve injuries
   • Hypertension/hypotension 1

Post-procedural care:

1. Duplex ultrasound surveillance within the first month after revascularization 1

2. Antiplatelet therapy:

   • After CEA: Continue long-term aspirin or clopidogrel 1
   • Given patient's history of CAD with stent, clopidogrel should be continued indefinitely

3. Aggressive risk factor management:

   • Statin therapy: High-intensity statin to achieve LDL <70 mg/dL 2
   • Blood pressure control: Target <130/80 mmHg 2
   • Diabetes management: Optimize glycemic control
   • Smoking cessation (if applicable)

Follow-up Protocol

1. First follow-up: Within 1 month with carotid duplex ultrasound 1
2. Regular follow-up: At least yearly to assess:
   • Neurological symptoms
   • Cardiovascular risk factors
   • Treatment adherence
   • Carotid ultrasound surveillance 1

Important Considerations and Pitfalls

1. Timing is critical: Delay in treatment increases risk of recurrent stroke

   • 14-day window for CEA after symptom onset is strongly supported by evidence 1

2. Antiplatelet management:

   • Do not discontinue antiplatelet therapy before CEA
   • Avoid excessive bleeding risk by maintaining proper DAPT duration (21 days minimum) 1, 2

3. Asymptomatic right carotid stenosis (55%):

   • Routine revascularization is not recommended for asymptomatic moderate stenosis 1
   • Monitor with regular ultrasound surveillance

4. Comprehensive vascular assessment:

   • Consider evaluation for other atherosclerotic disease given multiple risk factors
   • Assess for cardiac sources of emboli

The evidence strongly supports urgent intervention for this patient with symptomatic high-grade carotid stenosis. The combination of appropriate antiplatelet therapy and timely surgical intervention offers the best opportunity to prevent progression to a completed stroke.