Carotid-retinal embolism with coexistent mitral valve prolapse.

A 63-year-old hypertensive woman with a prolapsing mitral valve developed sudden blindness of the left eye secondary to a central retinal artery embolus. The decision to perform carotid arteriography led to discovery of an ulcerated plaque in the left internal carotid artery, which was found at the time of endarterectomy to bear a large friable platelet thrombus. The frequent occurrence of mitral valve prolapse in normal populations suggests that this anomaly may be incidental rather than etiologic in patients with cerebral embolic phenomena. The finding of mitral valve prolapse should not routinely exclude evaluation for other sources of embolic stroke.