Strokes result from blood clots that form in the atrium or upper heart chamber. The clots can travel to the brain, cutting blood supply and causing a stroke, as well as to other parts of the body. A stroke can be the first time a patient learns he or she has it because AF may be silent.
AF can result from disease of the heart valves but much more frequently from disease of the atria. In this article, I will address the stroke prevention treatment of the latter, called non valvular atrial fibrillation
Stroke risk is estimated using a score called CHA2DS2 VASC (see chart). The April 2014 guidelines for management of AF outline the risks and benefits of using anticoagulants to prevent stroke. The guidelines recommend anticoagulant therapy for a score of 2 or more and no therapy or aspirin for a 0 score. With a score of 1, no therapy, aspirin or an anticoagulant may be chosen. Aspirin may provide little if any protection and poses a bleeding risk.