Treatment of Cardioembolic Stroke
For patients with cardioembolic stroke, oral anticoagulation is the recommended long-term treatment for secondary prevention, but timing of initiation should be based on stroke severity, with delays of 1-12 days depending on the size of the infarct and presence of hemorrhagic transformation. 1
Acute Phase Management
- Immediate brain imaging (CT or MRI) is essential to exclude hemorrhage before initiating any antithrombotic therapy 1
- For eligible patients presenting within 3 hours of symptom onset, intravenous recombinant tissue plasminogen activator (r-tPA) is strongly recommended (Grade 1A) 2
- For patients presenting between 3-4.5 hours, IV r-tPA may be considered (Grade 2C) 2
- Systemic thrombolysis is contraindicated in patients on therapeutic oral anticoagulation (if INR >1.7 for warfarin users) 1, 2
- For patients with large vessel occlusion, endovascular thrombectomy should be considered within 6 hours of symptom onset, even in anticoagulated patients 1, 2
- Early aspirin therapy (160-325 mg) is recommended for patients with acute ischemic stroke who are not receiving thrombolysis 2
Timing of Anticoagulation Initiation
The timing of anticoagulation after cardioembolic stroke should follow this algorithm based on stroke severity 1, 2:
- TIA: Start oral anticoagulation 1 day after the event
- Mild stroke (NIHSS <8): Start oral anticoagulation 3 days after the event
- Moderate stroke (NIHSS 8-15): Start oral anticoagulation 6 days after the event
- Severe stroke (NIHSS ≥16): Start oral anticoagulation 12 days after the event
Anticoagulation Selection
- For patients with atrial fibrillation who have had a cardioembolic stroke, long-term oral anticoagulation is recommended, with a target INR of 2.0-3.0 for warfarin 1, 3
- Direct oral anticoagulants (DOACs) are appropriate alternatives to warfarin for non-valvular atrial fibrillation 1
- For patients with mechanical prosthetic heart valves, warfarin (target INR 2.0-3.0) is the anticoagulant of choice 1
- Avoid immediate full-dose anticoagulation in the acute phase as it increases risk of hemorrhagic transformation without clear benefit in preventing early recurrent stroke 1
Special Considerations
- For patients with restricted mobility after stroke, prophylactic-dose heparin or intermittent pneumatic compression devices are recommended to prevent venous thromboembolism 2
- Elastic compression stockings are not recommended for DVT prevention 2
- If oral anticoagulation is contraindicated, aspirin (75-325 mg/day) or clopidogrel (75 mg) should be used 1, 3
- Prolonged ECG monitoring for at least two weeks is recommended for patients with suspected cardioembolic stroke to detect paroxysmal atrial fibrillation 1
- Echocardiography should be considered for patients with suspected embolic stroke and normal neurovascular imaging 1, 4
Monitoring and Follow-up
- Regular monitoring of anticoagulation intensity is essential for patients on warfarin to maintain therapeutic INR range 1
- Patients with cardioembolic stroke are at high risk for early recurrence, with in-hospital mortality rates of up to 27.3% 4
- Secondary prevention with anticoagulants should be started according to the timing algorithm to prevent recurrent cardioembolic events 1, 4
- Patients with alcohol abuse, hypertension, valvular heart disease, nausea and vomiting, and previous cerebral infarction are at increased risk of early recurrent embolization 4
Pitfalls and Caveats
- Avoid using anticoagulation for non-cardioembolic ischemic stroke as it is not recommended and may increase bleeding risk 2
- Be cautious with thrombolytic therapy in patients with known intracardiac thrombi, as r-tPA may accelerate breakup or detachment of the thrombi and cause recurrent embolization 5
- The presence of multiple lacunar infarcts makes cardioembolic origin unlikely and may warrant different treatment approaches 4
- Ensure adequate hydration with isotonic intravenous normal saline to maintain euvolemia; volume expanders to achieve hemodilution are not recommended 2