Transient focal cerebral ischemic attacks are rare in patients who have episodes of cardiac dysrhythmias of the type associated with significant reduction in cardiac output. Of 290 patients who received pacemakers for disturbances of cardiac rhythm or conduction, only four had focal neurologic symptoms or signs, and only two (1%) had focal cerebral symptoms that could be related to a specific episode of cardiac dysfunction. The vast majority of the 290 patients had symptoms of general cerebral ischemia, primarily syncope.
Reed RL, Siekert RG, Merideth J. Rarity of Transient Focal Cerebral Ischemia in Cardiac Dysrhythmia. JAMA. 1973;223(8):893-895. doi:10.1001/jama.1973.03220080025006