What is the introduction of anticoagulants in the post-ischemic stroke period in patients with Atrial Fibrillation (AF)?

From the Guidelines

For patients with atrial fibrillation (AF) who have experienced an ischemic stroke, anticoagulation therapy with oral anticoagulants such as warfarin, dabigatran, rivaroxaban, or apixaban should be initiated to prevent recurrent strokes, as recommended by the 2014 AHA/ACC/HRS guideline 1. The introduction of anticoagulants in the post-ischemic stroke period is crucial to prevent recurrent strokes in patients with AF.

• The optimal anticoagulant therapy should be individualized based on shared decision making after discussion of the absolute risks and relative risks of stroke and bleeding and the patient’s values and preferences, as stated in the guideline 1.
• The CHA2DS2-VASc score is recommended for assessment of stroke risk in patients with nonvalvular AF, and oral anticoagulants are recommended for patients with a score of 2 or greater, or those with prior stroke, transient ischemic attack (TIA) 1.
• The choice of anticoagulant therapy should be based on the risk of thromboembolism, and options include warfarin, dabigatran, rivaroxaban, or apixaban, with the target international normalized ratio (INR) intensity for warfarin being 2.0 to 3.0 1.
• The decision to start anticoagulation involves balancing the risk of recurrent stroke against the risk of hemorrhagic transformation, and brain imaging should confirm absence of hemorrhage before initiating therapy.
• Long-term anticoagulation is typically required indefinitely for patients with AF to prevent future strokes, and the need for and choice of antithrombotic therapy should be reevaluated at periodic intervals to reassess stroke and bleeding risks 1.

From the FDA Drug Label

Oral anticoagulation therapy with warfarin is recommended in patients with persistent or paroxysmal AF (PAF) (intermittent AF) at high risk of stroke (i.e., having any of the following features: prior ischemic stroke, transient ischemic attack, or systemic embolism, age >75 years, moderately or severely impaired left ventricular systolic function and/or congestive heart failure, history of hypertension, or diabetes mellitus)

The introduction of anticoagulants in the post-ischemic stroke period in patients with Atrial Fibrillation (AF) is recommended for those at high risk of stroke, including patients with a history of prior ischemic stroke. The target INR for these patients is 2.0-3.0 2.

From the Research

Introduction of Anticoagulants in Post-Ischemic Stroke Period

• The introduction of anticoagulants in the post-ischemic stroke period in patients with Atrial Fibrillation (AF) is a crucial aspect of stroke prevention and management 3, 4.
• Studies have shown that anticoagulation therapy, including direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs), can significantly reduce the risk of stroke in patients with AF 5, 6.

Timing and Choice of Anticoagulants

• The timing of anticoagulant introduction after an ischemic stroke is critical, with current guidelines recommending oral anticoagulation alone for secondary prevention of stroke in patients with AF 6.
• The choice of anticoagulant, whether DOACs or VKAs, depends on various factors, including patient characteristics, stroke risk, and bleeding risk 3, 4.
• DOACs, such as apixaban, dabigatran, edoxaban, and rivaroxaban, have been shown to be effective and safe in preventing stroke in patients with AF, with a lower risk of intracranial bleeding compared to VKAs 4, 5.

Clinical Effectiveness of DOACs vs Warfarin

• Studies have compared the clinical effectiveness of DOACs and warfarin in patients with AF and ischemic stroke, with results showing that DOACs are associated with better outcomes, including reduced risk of major adverse cardiovascular events and improved patient-centered outcomes 7.
• The use of DOACs at discharge has been shown to be associated with more days at home and fewer deaths, all-cause readmissions, and cardiovascular readmissions compared to warfarin 7.

Considerations for Anticoagulant Use

• The use of anticoagulants in patients with AF and ischemic stroke requires careful consideration of individual patient characteristics, including renal function, liver disease, and bleeding risk 4, 5.
• The strategic dosage and lack of need for periodic prothrombin-time testing make DOACs an attractive option for patients with AF, particularly in older adults 4.