What are the findings and recommendations of the SAMPRIS (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis) trial?

SAMMPRIS Trial Summary: Findings and Implications

The SAMMPRIS (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis) trial demonstrated that aggressive medical management alone is superior to intracranial stenting plus medical management for preventing recurrent stroke in patients with symptomatic intracranial stenosis. 1

Key Findings of SAMMPRIS

Study Population and Design

• Patients with symptomatic intracranial stenosis of 70-99%
• Randomized to either:
  • Aggressive medical management alone
  • Aggressive medical management plus intracranial stenting using the Gateway-Wingspan system

Primary Results

• The trial was stopped prematurely due to higher-than-expected perioperative complications in the stenting group
• Medical management was shown to be superior to stenting plus medical management for preventing stroke recurrence

Aggressive Medical Management Protocol

The aggressive medical management arm consisted of:

• Dual antiplatelet therapy:
  • ASA 325 mg daily
  • Clopidogrel 75 mg daily
  • Started within 30 days of stroke/TIA and continued for up to 90 days 1
• Aggressive risk factor management:
  • Blood pressure control (target <140/90 mmHg)
  • Cholesterol management (target total cholesterol <200 mg/dL)
  • Diabetes management
  • Lifestyle modifications 1

Implications for Clinical Practice

Current Guideline Recommendations

Based on SAMMPRIS results, current guidelines recommend:

1. Intracranial stenting is not recommended for treatment of recently symptomatic intracranial 70-99% stenosis [Evidence Level B] 1

2. First-line treatment is aggressive medical management including:

   • Dual antiplatelet therapy (ASA + clopidogrel) for up to 90 days
   • Aggressive management of all vascular risk factors 1

3. Aspirin is recommended over warfarin for patients with stroke or TIA due to 50-99% stenosis of a major intracranial artery 1

4. Blood pressure and lipid targets:

   • Long-term BP maintenance <140/90 mmHg
   • Total cholesterol <200 mg/dL 1

Special Considerations

Refractory Cases

For patients who experience recurrent stroke despite maximal medical therapy:

• Intracranial angioplasty (with or without stenting) may be considered in carefully selected patients [Evidence Level C] 1
• However, this should be approached with caution given the SAMMPRIS results

Real-World Application Challenges

A 2017 study found that the 30-day risk of recurrent stroke in real-world settings was higher (20.4%) than observed in the SAMMPRIS medical arm (4.4%), even with aggressive medical management 2. This suggests:

• Challenges in implementing the SAMMPRIS protocol in routine clinical practice
• Need for careful patient monitoring and adherence to the aggressive medical regimen

Recent Evidence

The CASSISS trial (2022) further confirmed SAMMPRIS findings, showing no significant difference in stroke or death between stenting plus medical therapy versus medical therapy alone in patients with symptomatic severe intracranial atherosclerotic stenosis 3.

Practical Management Algorithm

1. For patients with symptomatic intracranial stenosis (50-99%):

   • Initiate aggressive medical management:
     • Dual antiplatelet therapy (ASA 325mg + clopidogrel 75mg daily) for 90 days
     • Single antiplatelet therapy thereafter
     • Target BP <140/90 mmHg
     • Target total cholesterol <200 mg/dL
     • Aggressive diabetes management if applicable
     • Lifestyle modifications (smoking cessation, diet, exercise)

2. Monitor closely for recurrent symptoms

3. If recurrent stroke occurs despite maximal medical therapy:

   • Consider referral to specialized center for evaluation
   • Angioplasty without stenting may be considered as a potentially safer alternative to stenting in selected cases 4
   • Any intervention should be performed by highly experienced operators with documented low complication rates

Common Pitfalls to Avoid

• Premature consideration of stenting before optimizing medical management
• Inadequate risk factor control (particularly BP and cholesterol)
• Insufficient duration of dual antiplatelet therapy
• Failure to recognize that stenting carries significant procedural risks that outweigh benefits in most patients