The multiple causes of stroke in atrial fibrillation: Thinking broadly

Publication date: Available online 30 August 2018Source: Canadian Journal of CardiologyAuthor(s): Atlantic D’Souza, Kenneth S. Butcher, Brian H. BuckAbstract:Atrial Fibrillation (AF) is numerically the most important risk factor for stroke. It is well established that patients with AF have a five-fold increased risk of stroke relative to those without, and that anticoagulation reduces the risk of stroke by approximately two-thirds. Definitively attributing the mechanism of an individual stroke to AF is much more problematic, however. In fact, there is no way to reliably establish the etiology of any ischemic infarction. This necessitates screening for all potential stroke risk factors and treating accordingly.The pattern of infarction is often used to classify the presumed mechanism of infarction as thrombotic, or embolic, although even this is approach is based on association and increasingly is recognized as not completely reliable. Furthermore, it should not dictate management—patients with perforating arterial territory infarcts with AF also require and benefit from anticoagulation. Similarly, if other potential embolic sources beyond AF are identified, anticoagulation remains the standard of care.The traditional conceptual model of the mechanistic link between AF and cardioembolic infarction is likely over-simplified. Long-term cardiac rhythm recording studies indicate an inconsistent temporal relationship between AF and infarction. This suggests that cardioembolic s...
Source: Canadian Journal of Cardiology - Category: Cardiology Source Type: research