Causes of ischemic stroke in patients with atrial fibrillation

Abstract

Objective: Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting 1% of the adult population. However, ischemic strokes in patients with AF can be triggered by alternative mechanisms, especially in high-risk patients with additional vascular risk factors. In some patients, atherothrombotic mechanisms may cause stroke, and AF may be incidental or a symptom of atherosclerotic disease. In this case, it may be difficult to distinguish cardioembolic stroke from stroke due to large artery atherosclerosis. The aim of this study was to determine the causes of non-cardioembolic ischemic stroke in patients with non-valvular AF and to determine the risk factors for craniocervical atherosclerotic stenosis.Materials and Methods: This study identified risk factors for craniocervical atherosclerotic stenosis in patients followed up at the Uludag University Faculty of Medicine Department of Neurology with a diagnosis of ischemic stroke and non-valvular AF. In this study, 180 patients who were followed up with a diagnosis of non-valvular AF and acute ischemic stroke between January 1st, 2019 - March 1st 2020, in Uludag University Faculty of Medicine Department of Neurology, were retrospectively included.Results: In this study, the non-cardiac stroke rate was 20% in patients with non-valvular AF who had acute ischemic stroke. Ischemic stroke due to large vessel atherosclerosis was found in 14.4% of these patients, and 9.5% of all patients with AF were stented. When dermographic features, clinical features, and risk factors were analyzed for craniocervical atherosclerotic stenosis, a significant statistical result was obtained with male sex (p=0.020) and smoking (p<0.001).Conclusion: Stroke is a heterogeneous group of diseases caused by many complex mechanisms. Prevention of stroke recurrence is possible by starting effective treatment early. The presence of critical artery stenosis in a patient with acute ischemic stroke with AF causes stroke recurrence and this relapse cannot be prevented by anticoagulant treatment. Angiographic evidence also revealed ethnic and racial differences in patients with acute ischemic stroke. Therefore, more precise information can be obtained through prospective studies in our population.