What are the anticoagulant guidelines for secondary prevention of ischemic stroke?

From the Guidelines

Anticoagulants are recommended for stroke secondary prevention in patients with atrial fibrillation or other cardioembolic sources, with direct oral anticoagulants (DOACs) preferred over warfarin due to their lower risk of intracranial hemorrhage, as stated in the 2021 American Heart Association guideline 1. The recommended DOACs include apixaban, dabigatran, edoxaban, or rivaroxaban, which should be selected in preference to warfarin for patients with atrial fibrillation or flutter, except for patients with moderate to severe mitral stenosis or a mechanical heart valve 1. Some key points to consider when prescribing anticoagulants for stroke secondary prevention include:

• Assessing bleeding risk using tools like HAS-BLED score and addressing modifiable risk factors
• Regular monitoring of renal function, especially for patients on DOACs
• Emphasizing medication adherence due to the short half-lives of these drugs
• Initiating anticoagulation within 4-14 days after ischemic stroke, with timing based on stroke severity
• Considering antiplatelet therapy, such as aspirin, for patients who cannot tolerate anticoagulation, but noting that antiplatelet therapy is not a substitute for anticoagulation in patients with atrial fibrillation 1. It is essential to weigh the benefits and risks of anticoagulation for each patient, taking into account their individual characteristics, such as renal function, bleeding risk, and stroke severity, as well as their preferences and values 1. In terms of specific dosing, the 2021 American Heart Association guideline recommends selecting apixaban, dabigatran, edoxaban, or rivaroxaban, without providing specific dosing recommendations, highlighting the importance of individualizing treatment based on patient characteristics and clinical judgment 1.

From the Research

Anticoagulant Guidelines for Stroke Secondary Prevention

• The use of non-vitamin K antagonist oral anticoagulants (NOACs) has been proven to be safer and equally effective compared to warfarin in stroke prevention for patients with nonvalvular atrial fibrillation 2.
• NOACs, such as apixaban, dabigatran, and rivaroxaban, have been shown to have a favorable safety profile, with a decreased risk of intracranial bleeding compared to warfarin 3.
• Direct comparisons of effectiveness and safety among apixaban, dabigatran, and rivaroxaban have found that patients treated with standard dose apixaban or dabigatran had a lower risk of major bleeding than patients treated with rivaroxaban 4.
• In reduced dose, patients treated with apixaban had a lower risk of major bleeding than those treated with dabigatran or rivaroxaban 4.
• Secondary prevention trials have found that anticoagulation therapy can achieve outcomes comparable to those of randomized trials, with a recurrent stroke rate of 5.1% per year and a major hemorrhage rate of 2.3% per year 5.
• The choice of anticoagulant should be based on individual patient characteristics, including stroke subtype, with consideration given to the risk of bleeding and the effectiveness of the treatment 5.
• Ongoing trials are addressing the optimal timing of NOAC initiation after a recent ischemic stroke and the benefit-harm ratio of NOAC treatment in patients with atrial fibrillation and a history of previous intracranial bleeding 2.
• The additive value of prolonged cardiac monitoring for subclinical atrial fibrillation detection and the optimal medical management of individuals with covert paroxysmal atrial fibrillation are topics of intensive research interest 2.