Bicuspid aortic valve represents the most common congenital heart abnormality. In the absence of endocarditis, the association between bicuspid aortic valve and cerebral ischemia has only recently been suggested. ''Spectacular shrinking deficit’ is a term coined to describe a major hemispheric syndrome that resolves significantly over a short period. It has been associated with cardiogenic embolism. A 46-year-old man presented with a severe nondominant syndrome which spontaneously resolved within 1 h. Noninvasive investigation suggested that a congenital bicuspid aortic valve was the most plausible cause of reversible cerebral ischemia. Patients who present with dramatic though transient ischemic deficits should be investigated for a cardiac source of embolism. Congenital bicuspid aortic valve may be an under-recognized source of embolism in such cases.