What are the current guidelines for treating symptomatic intracranial arterial stenosis?

From the Guidelines

Aggressive medical management is the recommended first-line therapy for symptomatic intracranial stenosis, with a focus on dual antiplatelet therapy, high-intensity statin therapy, blood pressure control, and lifestyle modifications, as supported by the 2021 guideline from the American Heart Association/American Stroke Association 1.

Key Recommendations

• Dual antiplatelet therapy is not well established for secondary stroke prevention in patients with 50% to 99% stenosis of a major intracranial artery, according to the 2021 guideline 1.
• Maintenance of systolic blood pressure below 140 mm Hg, high-intensity statin therapy, and at least moderate physical activity are recommended to prevent recurrent stroke and vascular events in patients with stroke or TIA attributable to 50% to 99% stenosis of a major intracranial artery 1.
• Angioplasty and stenting should not be performed as an initial treatment for patients with a stroke or TIA attributable to severe stenosis (70%–99%) of a major intracranial artery, due to the associated harm 1.

Medical Management

• The medical management arm includes dual antiplatelet therapy with ASA 325 mg and Clopidogrel 75 mg started within 30 days of stroke or transient ischemic attack and treated for up to 90 days, as well as aggressive management of all vascular risk factors, including blood pressure, lipids, diabetes mellitus, and other at-risk lifestyle patterns 1.
• High-intensity statin therapy, such as atorvastatin 40-80 mg or rosuvastatin 20-40 mg daily, is recommended regardless of baseline cholesterol levels.
• Blood pressure should be controlled to a target below 140/90 mmHg (or lower if tolerated), typically using ACE inhibitors or ARBs.

Endovascular Interventions

• Endovascular interventions like stenting are generally reserved for patients who experience recurrent strokes despite maximal medical therapy, particularly those with 70-99% stenosis 1.
• Close monitoring with transcranial Doppler or other imaging is recommended to assess stenosis progression.

Lifestyle Modifications

• Lifestyle modifications are crucial, including smoking cessation, regular physical activity, and dietary changes to manage diabetes and reduce cholesterol.
• These modifications should be individualized and tailored to each patient's specific needs and risk factors.

From the Research

Treatment Guidelines for Symptomatic Intracranial Stenosis

• The optimal medical management of atherosclerotic intracranial stenosis involves aggressive medical management, with intensive risk factor control and antithrombotic therapy, as shown to be beneficial in reducing the high risk of recurrent stroke in patients with symptomatic intracranial atherosclerotic stenosis (sICAS) 2.
• High-intensity statins are recommended for patients with atherosclerotic stroke, including sICAS, with a treatment target of low-density lipoprotein <70 mg/dL 2.
• For patients with diabetes, the goal is to treat to hemoglobin A1C ≤7% for most patients through a combination of diet, insulin, and hypoglycemic drugs 2.
• Some degree of physical activity, such as walking or stationary biking, should be encouraged in all patients with sICAS who are not severely disabled, with a minimum of 10 minutes of moderate-intensity aerobic activity 4 times a week recommended for patients who are capable of exercise 2.
• Dual antiplatelet therapy for up to 90 days followed by single antiplatelet agent is recommended for all patients with severe sICAS (70%-99% stenosis) 2.

Comparison of Medical and Endovascular Therapy

• Endovascular treatment of intracranial arterial stenosis is a rapidly evolving therapeutic option, with antiplatelet agents currently recommended as the primary treatment for symptomatic intracranial stenosis, and endovascular therapy reserved for appropriate high-risk cases refractory to medical therapy 3.
• The impact of stenosis degree on outcomes of stenting compared with medical therapy alone in patients with symptomatic intracranial artery stenosis has been explored, with results suggesting that patients with higher degrees of stenosis are more likely to benefit from stenting 4.
• Aggressive medical management has been associated with half the risk of stroke compared to that in similar patients in a previous symptomatic intracranial stenosis trial after adjustment of confounding characteristics 5.

Management of Symptomatic Intracranial Stenosis

• Intracranial atherosclerotic disease is a common cause of stroke worldwide, causing approximately 10% of strokes in the USA and up to 50% in Asian populations, with recurrent stroke risks particularly high in those with a stenosis of 70% or more and a recent transient ischemic attack or stroke 5.
• Warfarin has been associated with higher major hemorrhage rates and no reduction of recurrent stroke compared to aspirin in patients with symptomatic intracranial stenosis 3, 5.
• A randomized controlled trial of intracranial stenting plus aggressive medical therapy versus aggressive medical therapy alone is needed to determine the optimal treatment for patients with severe symptomatic intracranial stenosis 6.