(i) Atrial fibrillation
Aggressive screening for atrial fibrillation in patients over 65 years of age by pulse check with additional electrocardiography if necessary may be beneficial in primary care settings (class IIa/class B).
In all patients with non-valvular atrial fibrillation with a high risk of stroke (hereafter referred to as risk) and in most patients with non-valvular atrial fibrillation with moderate risk, warfarin is recommended if it is safe to administer and the dose is adjusted so that the international normalized rate (INR) of prothrombin time is between 2.0 and 3.0 (Class I/Class A).
Aspirin antiplatelet therapy may be recommended for low-risk patients and some moderate-risk patients based on individual patient preference, results of anticoagulation bleeding risk assessment, and conditions of anticoagulation index monitoring (Class I/Class A).
In patients with high-risk atrial fibrillation who are not amenable to anticoagulation, dual antiplatelet therapy with clopidogrel + aspirin may provide better stroke prevention compared with aspirin alone, but may be justified by the increased risk of serious bleeding (Class IIb/Grade B).
In elderly patients with atrial fibrillation, antithrombotic therapy combined with aggressive blood pressure management may be beneficial (Class IIa/Grade B).
(ii) Cardiac problems
(i) The American College of Cardiology and Heart Association (ACC/AHA) guidelines provide strategies related to stroke risk reduction for various cardiac conditions (including heart valve disease, unstable angina, chronic stable angina, and acute myocardial infarction), which should be endorsed in this guideline.
Screening for cardiac lesions (e.g., oval foramen may not be necessary) is not recommended for patients without neurological lesions, or without a specific cardiac cause (Class III/Class A).
The use of warfarin for stroke prevention is reasonable in patients after myocardial infarction with ST-segment elevation and associated left ventricular appendage thrombus or left ventricular wall segmental motion inability (Class IIa/Class A).
(iii) Asymptomatic carotid stenosis
Patients with asymptomatic carotid stenosis should be screened for other treatable risk factors for stroke and treated with appropriate lifestyle modification and medication (Class I/Class C).
Patients with asymptomatic carotid stenosis should be selected for carotid angioplasty, including endarterectomy (CEA) and stenting (CAS), based on assessment of systemic disease and life expectancy, consideration of individual factors, adequate discussion of the benefits and risks of the procedure, and understanding of patient preferences (Class I/Class C)
Given that all carotid endarterectomy (CEA) studies used aspirin as an antiplatelet agent, the use of aspirin as adjuvant therapy is recommended for all patients with CEA, except in contraindicated cases (Class I/Class C).
In selected patients with asymptomatic carotid stenosis (angiographic stenosis >60% or Doppler ultrasound stenosis >70% and proven), prophylactic CEA surgery is beneficial only when residual rates and mortality are <3% (Class IIa/Class A). It is important to note that the benefits of surgery as demonstrated in previous trials may be relatively low due to advances in drug therapy, and the proposed 3% allowance for surgical comorbidities may be high.
Prophylactic carotid stenting (CAS) may be considered in selected patients with asymptomatic carotid stenosis (arteriogram > 60%, confirmed Doppler ultrasound > 70%, or ultrasound stenosis of 50-69% but CTA or MRA > 80%). The superiority of angioplasty over current pharmacologic therapy is not fully established (class IIb/class B).
The effectiveness of CAS as an alternative therapy has not been established in patients with asymptomatic carotid stenosis who are at high risk for CEA surgery (Class IIb/Grade C).
Screening for asymptomatic carotid stenosis in the population is not recommended (Class III/Grade B).
(iv) Sickle cell disease (SCD)
Children with SCD should be screened for stroke risk with transcranial Doppler cerebrovascular ultrasound (TCD) from age 2 years (class I/level B).
the optimal screening interval is not defined, but more frequent screening is reasonable in younger children and in children with TCD flow velocities at the borderline of abnormality for timely detection of high-risk TCD flow velocity changes requiring treatment (class IIa/level B)
in children at high risk of stroke, transfusion therapy (goal: S hemoglobin reduction from >90% to <30%) is effective in reducing stroke risk (Class I/Grade B).
Continued transfusion is likely to be required pending the results of further studies, including those whose TCD flow rate has returned to normal (Class IIa/Grade B).
Hydroxyurea or bone marrow transplantation may be considered for children at high risk of stroke who are unable or unwilling to undergo regular red blood cell therapy (Class IIb/Grade C).
For the selection of indications for transfusion for stroke prevention, the criteria for magnetic resonance imaging (MRI) of the brain and magnetic resonance angiography (MRA) have not been established and such methods are not recommended as an alternative to TCD for this purpose (Class III/Grade B).
For adult patients with SCD, screening for known stroke risk factors should be performed and managed according to these guidelines (Class I/Class A).
(v) Hormone replacement therapy during menopause
Hormone therapy (estrogen ± megestrol acetate) should not be used for primary stroke prevention in postmenopausal women (Class III/Class A).
Selective stimulant receptor modulators (raloxifene, tamoxifen, tibolone, etc.) should not be used for primary prevention of stroke (Class III/Class A).