Secondary prevention after cardioembolic stroke

Cardiac causes of ischemic stroke usually lead to severe neurological deficits from large intracranial artery occlusion compared to small vessel ischemic stroke. The most common cause of cardioembolic stroke is nonvalvular atrial fibrillation (AF), which has an increasing incidence with age. AF stroke trials demonstrate that anticoagulation is superior to antiplatelet therapy for cerebral and systemic embolism prevention. Warfarin, the mainstay for decades, has been compared with direct thrombin (Factor II) inhibitors and Factor Xa inhibitors, which are collectively referred to as the direct oral anticoagulants (DOACs). Overall, DOACs have been found to be at least equally effective in reducing ischemic stroke as compared to warfarin with less intracranial bleeding risk. Patent foramen ovale (PFO) is a common finding on echocardiograms in patients with and without stroke, found in approximately 25% of the population, and a controversial source of cryptogenic stroke because of its overrepresentation in the cryptogenic stroke population (upward of 50%). Clinical trials suggest that cryptogenic stroke patients who are relatively young (<60 years), have a large PFO, and have clear embolic pattern of cerebral infarct benefit from PFO closure with a double disk device in addition to antiplatelet therapy as compared to antiplatelet therapy alone. Other less common causes of cardioembolic stroke include myocardial infarction, left ventricular thrombus, reduced left ventricular ejection fraction, valvular abnormalities, and endocarditis and left atrial cardiopathy. The best way to prevent cardioembolic stroke on a population basis remains early detection and treatment of AF in eligible patients.