An update on cardioembolic stroke.

About one-fifth of all ischaemic strokes are cardioembolic. Recent years have seen considerable progress in our understanding of atrial fibrillation, the most important cause of cardioembolism, and evidence-based treatment strategies have emerged. Progress in relation to other cardioembolic disorders has been more limited and here stroke prevention strategies remain less certain and subject to debate. This article briefly reviews the methods currently used to identify and investigate cardioembolic stroke and then provides an update on stroke prevention in relation to atrial fibrillation, valvular heart disease, patent foramen ovale and left ventricular dysfunction (after myocardial infarction and chronic failure).