Anticoagulation Timing and Selection in Ischemic Stroke

Introduction to Anticoagulation Timing

The American Heart Association recommends starting anticoagulation immediately after a transient ischemic attack (TIA) in patients with atrial fibrillation to reduce recurrent stroke risk 1, 2
For patients with ischemic stroke and atrial fibrillation, anticoagulation should be initiated 2-14 days after the index event in those with low risk for hemorrhagic conversion 1, 2
In patients with high risk for hemorrhagic conversion, anticoagulation should be delayed beyond 14 days to reduce intracranial hemorrhage risk 1, 2

Direct oral anticoagulants (DOACs) are preferred over warfarin for nonvalvular atrial fibrillation, with options including apixaban, dabigatran, edoxaban, or rivaroxaban 1, 2, 3, 4
The American College of Cardiology recommends using DOACs as first-line treatment for stroke prevention in patients with atrial fibrillation 3, 4
Warfarin is indicated for patients with moderate to severe mitral stenosis, mechanical heart valves, or end-stage renal disease or dialysis 1, 2

In patients with valvular heart disease, warfarin (INR 2.5-3.5) plus aspirin 75-100 mg daily is recommended for mechanical mitral valve 3, 4
For patients with left ventricular or atrial thrombus, anticoagulation for at least 3 months is recommended, with vitamin K antagonists preferred for left atrial/appendage thrombus with cardiomyopathy 3, 4

The European Stroke Organisation recommends confirming absence of hemorrhagic transformation on neuroimaging before initiating anticoagulation 5
Repeat imaging at 7-10 days is recommended if higher-grade hemorrhagic transformation is present 5
Patients with atrial fibrillation and TIA or ischemic stroke should not receive antiplatelets for secondary stroke prevention if anticoagulation is indicated 3, 4