What is the recommended treatment for a patient with large artery disease due to 100% narrowing of intracranial atherosclerosis, including dual antiplatelet therapy dosage?

Treatment of 100% Intracranial Atherosclerotic Occlusion

For a patient with 100% (complete) occlusion of an intracranial artery due to atherosclerosis, revascularization procedures are not recommended, and treatment should focus on aggressive medical management with single antiplatelet therapy, not dual antiplatelet therapy. 1

Why Revascularization is Contraindicated

• Carotid revascularization (including stenting or endarterectomy) is explicitly not recommended for patients with chronic total occlusion of the targeted artery. 1
• This contraindication applies to both extracranial and intracranial complete occlusions, as the risk-benefit ratio does not favor intervention in this setting. 1

Antiplatelet Therapy Recommendations

Single Antiplatelet Therapy is Standard

For intracranial atherosclerotic disease with 50-99% stenosis, aspirin 325 mg daily is recommended over oral anticoagulation, and there are no strong recommendations supporting dual antiplatelet therapy (DAPT) over single antiplatelet therapy (SAPT) in this population. 1

• The evidence base (SAMMPRIS trial) demonstrated that DAPT is superior to stenting, but did not prove DAPT is superior to SAPT for intracranial atherosclerotic disease. 1
• A post-hoc analysis of the CHANCE trial showed no differences in the beneficial effect of DAPT versus SAPT in minor stroke patients with versus without intracranial atherosclerotic disease. 1

When DAPT Would Be Considered (Not Applicable to 100% Occlusion)

For context, DAPT is only recommended in specific acute scenarios that do not apply to chronic total occlusion:

• DAPT with aspirin 81 mg daily plus clopidogrel 75 mg daily is indicated for minor ischemic stroke (NIHSS ≤3) or high-risk TIA within 12-24 hours of symptom onset, continued for 21 days. 1, 2
• Loading doses of aspirin 160-325 mg plus clopidogrel 300-600 mg should be given at initiation. 1, 2
• This acute DAPT protocol applies to patients with patent vessels and recent symptoms, not chronic occlusions. 1, 2

Comprehensive Medical Management for 100% Occlusion

Antiplatelet Monotherapy

Long-term single antiplatelet therapy is indicated for all patients with non-cardioembolic ischemic stroke who do not require anticoagulation. 1

Acceptable options include:

• Aspirin 81-325 mg daily 1
• Clopidogrel 75 mg daily 1
• Aspirin 25 mg plus extended-release dipyridamole 200 mg twice daily 1

Blood Pressure Management

• Target systolic blood pressure <140 mmHg is recommended for patients with intracranial atherosclerotic disease. 1, 2
• Blood pressure must be cautiously managed in the early acute phase but aggressively controlled long-term. 3

Lipid Management

• High-dose statin therapy is recommended to achieve an LDL cholesterol target of 1.8 mmol/L (70 mg/dL). 1, 2
• Statin therapy should be initiated regardless of baseline lipid levels for atherosclerotic stroke prevention. 4

Additional Risk Factor Control

• At least moderate physical activity is recommended. 1, 2
• Aggressive diabetes control, smoking cessation, diet modification, and exercise are essential components of medical management. 1, 2

Critical Pitfalls to Avoid

Do Not Use Anticoagulation

Anticoagulation is not recommended for intracranial atherosclerotic disease unless there is another indication such as atrial fibrillation. 1, 2

• Warfarin has been shown to be no more effective than aspirin and carries significantly higher bleeding risk in this population. 3, 4

Do Not Pursue Revascularization

For chronic total occlusion (100% stenosis), neither angioplasty nor stenting should be performed. 1

• Even for patent vessels with 50-99% stenosis, angioplasty and stenting are not recommended based on SAMMPRIS trial results showing superiority of aggressive medical management. 1, 2

Do Not Extend DAPT Beyond Indicated Duration

If DAPT were initiated for an acute event (which would not apply to chronic occlusion):

• Never extend DAPT beyond 21-90 days for intracranial atherosclerotic disease without stenting, as prolonged therapy increases bleeding risk without additional benefit. 2, 5

Clinical Context: Complete Occlusion vs. High-Grade Stenosis

The distinction between 100% occlusion and 50-99% stenosis is critical:

• Guidelines for intracranial atherosclerotic disease specifically address 50-99% stenosis, not complete occlusion. 1
• Complete occlusion represents a fundamentally different pathophysiologic state where the vessel is chronically occluded and collateral circulation has developed. 1
• The focus shifts entirely to preventing new events in other vascular territories through aggressive medical management rather than attempting to recanalize a chronically occluded vessel. 1