What are the treatment options for a patient presenting 10 hours after the onset of acute ischemic stroke symptoms?

Treatment Options for Acute Ischemic Stroke at 10 Hours After Onset

At 10 hours after stroke onset, intravenous alteplase is NOT recommended as standard therapy, but endovascular thrombectomy remains a viable option for carefully selected patients with large vessel occlusion and salvageable brain tissue identified on advanced imaging. 1

Intravenous Thrombolysis: Not Standard at 10 Hours

• The standard time window for IV alteplase is up to 4.5 hours from symptom onset or last known well 1
• Treatment beyond 4.5 hours is not FDA-approved and falls outside established guideline recommendations for routine use 1
• The 2018 AHA/ASA guidelines establish 4.5 hours as the upper limit for standard IV alteplase administration 1

Extended Window Considerations (Beyond Guidelines)

While not standard practice at 10 hours, emerging evidence suggests potential benefit in highly selected cases:

• Perfusion imaging-selected patients may benefit from IV alteplase up to 9 hours when salvageable tissue is demonstrated on CT perfusion or MRI diffusion-weighted imaging 1, 2
• The EXTEND trial showed improved functional outcomes (35.4% vs 29.5% with placebo) when alteplase was given 4.5-9 hours after onset in patients selected by perfusion imaging, though symptomatic ICH increased (6.2% vs 0.9%) 2
• The Canadian guidelines note that MRI-selected patients (DWI-FLAIR mismatch) may benefit beyond 4.5 hours, but this requires consultation with stroke expertise and is not proven with CT-based selection 1

Critical caveat: At 10 hours, this approach is investigational and requires specialized stroke center capabilities with advanced imaging and neurological expertise 1

Endovascular Thrombectomy: Primary Option at 10 Hours

For patients with large vessel occlusion, mechanical thrombectomy is the recommended treatment at 10 hours 1, 3

Patient Selection Criteria

• Time window: Up to 24 hours from last known well for highly selected patients 1
• Imaging requirements at 10 hours: Advanced neurovascular imaging with CT perfusion or MRI diffusion-weighted imaging to demonstrate salvageable tissue 1
• Specific imaging criteria: Small ischemic core (typically ≤70 mL), substantial penumbra (≥10-15 mL), and favorable mismatch ratio 1, 3
• Target vessels: Anterior circulation large vessel occlusion (internal carotid artery, M1/proximal M2 middle cerebral artery) 1

Technical Approach

• Stent retriever devices are the standard technique, achieving recanalization rates of 72-88% 3
• Goal is modified TICI 2b/3 reperfusion 4
• Treatment provides 50% increase in good functional outcomes compared to medical therapy alone for large vessel occlusion 3

Clinical Algorithm for 10-Hour Presentation

1. Immediate CT scan to exclude hemorrhage 4
2. CT angiography to identify large vessel occlusion 1, 4
3. If large vessel occlusion present: Obtain CT perfusion or MRI to assess salvageable tissue 1
4. If favorable imaging profile: Proceed directly to mechanical thrombectomy 1
5. If no large vessel occlusion or unfavorable imaging: Medical management only (antiplatelet therapy after 24 hours, supportive care) 1

Important Safety Considerations

• Do not administer IV alteplase at 10 hours outside of clinical trials or highly specialized centers with perfusion imaging capabilities 1
• Symptomatic ICH risk increases substantially with delayed thrombolysis, particularly beyond 4.5 hours 5, 2
• Hyperglycemia (>11.1 mmol/L) dramatically increases hemorrhage risk and should be corrected before any reperfusion therapy 3
• Blood pressure must be controlled to <185/110 mmHg before any intervention 1, 4

Supportive Care Measures

• Maintain oxygen saturation >94% 4
• Correct hypoglycemia immediately; treat hyperglycemia to target range 4
• Continuous cardiac monitoring for at least 24 hours 4
• Treat fever >38°C with antipyretics 4
• Avoid antiplatelet agents and anticoagulants until 24 hours after any thrombolytic therapy 4

Bottom line: At 10 hours, mechanical thrombectomy for large vessel occlusion with favorable imaging is the evidence-based treatment; IV thrombolysis is not recommended outside of research protocols with advanced perfusion imaging selection 1, 3