What is the recommended antiplatelet (antiplatelet) therapy for patients with ischemic stroke due to atrial fibrillation (AF) while awaiting anticoagulation?

Antiplatelet Therapy for AF-Related Ischemic Stroke While Awaiting Anticoagulation

Aspirin (160-325 mg daily) should be initiated early in the acute phase of ischemic stroke due to atrial fibrillation, but antiplatelet therapy should NOT be used as a bridging strategy while waiting to start oral anticoagulation. 1

Acute Phase Management (First 48 Hours)

Early aspirin is recommended for acute stroke management, but NOT as bridging therapy:

• Aspirin 160-325 mg should be started within 48 hours of acute ischemic stroke for all patients, including those with AF 1
• This early aspirin reduces early recurrent stroke and improves outcomes in the acute phase 1
• However, heparinoids (LMWH or UFH) should NOT be used as bridging therapy in acute AF-related stroke, as they increase symptomatic intracranial hemorrhage risk without net benefit 1, 2
• Very early anticoagulation (<48 hours) with warfarin or DOACs should be avoided due to increased hemorrhagic transformation risk 1, 2

Transition to Anticoagulation

Stop antiplatelet therapy when starting oral anticoagulation:

• Oral anticoagulation should typically be initiated within 2 weeks of stroke, with exact timing based on stroke severity 1, 2
• Once oral anticoagulation is started, antiplatelet therapy should be discontinued 1, 3
• The combination of OAC plus antiplatelet in AF patients without coronary disease provides no additional stroke prevention benefit and significantly increases bleeding risk 4, 5

Timing Algorithm for Anticoagulation Initiation:

• TIA (no infarct on imaging): Start anticoagulation at 1 day 2
• Mild stroke (NIHSS <8): Start anticoagulation at 3 days 2
• Moderate stroke (NIHSS 8-15): Start anticoagulation at 6-8 days 2
• Severe stroke (NIHSS ≥16): Start anticoagulation at 12-14 days 2

Critical Pitfalls to Avoid

Do NOT use antiplatelet monotherapy as long-term secondary prevention:

• Antiplatelet therapy alone (without OAC) in AF patients after stroke significantly increases risk of recurrent stroke and death compared to OAC alone (HR 1.31,95% CI 1.14-1.50) 6
• Antiplatelet monotherapy should never be used for secondary prevention in AF-related stroke except when absolute contraindications to anticoagulation exist 1, 3, 4
• Aspirin is inferior to warfarin for stroke prevention in AF, and this gap widens further with DOACs 7, 8

Do NOT combine antiplatelet with anticoagulation unless specific coronary indication:

• For AF patients with stable coronary disease (>12 months from ACS), OAC monotherapy is preferred over OAC plus aspirin 1
• Adding aspirin to anticoagulation increases major bleeding by 1.6% per year without reducing stroke or MI 5
• The combination of OAC plus antiplatelet increases mortality risk without additional stroke prevention benefit 4

Special Circumstances Requiring Dual Therapy

Only use antiplatelet plus anticoagulation in these specific scenarios:

• Recent ACS (<12 months) or recent PCI/stenting: Use triple therapy (OAC + aspirin + clopidogrel) for 1-3 months, then dual therapy (OAC + clopidogrel) up to 12 months based on bleeding risk 1
• If aspirin must be combined with OAC, use low-dose aspirin 75-100 mg daily with PPI for GI protection 1
• Prefer clopidogrel over aspirin when combining P2Y12 inhibitor with OAC 1

VTE Prophylaxis During Immobilization

Prophylactic anticoagulation for immobility is different from therapeutic anticoagulation:

• Use prophylactic-dose LMWH or intermittent pneumatic compression for immobilized stroke patients starting 2-4 days post-stroke 1, 3, 9
• This is for DVT/PE prevention, NOT for stroke prevention 3
• Avoid elastic compression stockings (not effective) 1