History of Cardiac Embolism

In 1742, for the first time, Gerhard van Swieten postulated that embolism might arise inside the heart chambers and great vessels, but another century was needed before clinicians became accustomed to the concept that embolism can lead to occlusion of the brain artery. In fact, in 1875, Gowers described a case of blindness and contralateral hemiplegia in a patient with mitral stenosis. At autopsy, emboli were found in the middle cerebral artery and in the central retinal artery. Specifically, emboli were found to originate from clots on the auricular appendices. Subsequently, in 1954, Fisher demonstrated that a thromboembolic mechanism underlies most ischemic strokes, and that the source of thrombus might be the heart rather than a proximal arterial lesion. He suggested that the embolus might have arisen after myocardial infarction in the fibrillating atrial appendage. In 1977, a necropsy study provided additional evidence supporting the role of atrial fibrillation as a crucial cause of cerebral embolism, and this was later confirmed by large epidemiological studies. Finally, in the first half of the 1990s, several studies reported that oral anticoagulants consistently reduced the risk of stroke in patients with atrial fibrillation. Oral anticoagulants currently remain the most powerful stroke prevention strategy available for patients with atrial fibrillation.