Stroke is being considered the second most common cause of death and the third most common cause of disability worldwide. For each patient of ischemic stroke, the prognosis, treatment strategy, and further risk of recurrence depend on the presumed etiology. Cardioembolic causes of stroke are responsible for up to 20% of ischemic strokes with a high rate of recurrence. Atrial fibrillation (AF) is the most common risk factor for cardioembolic stroke. This chapter covers the clinical features of cardioembolic stroke, acute myocardial infarction and stroke, cardiomyopathy and stroke, heart failure and stroke, valvular heart disease and stroke, patent foramen ovale and stroke, and glycemic control and stroke.