To assess the incidence and severity of cardiac arrhythmias in the acute period following a cerebrovascular accident (CVA), 30 patients with a CVA in a stroke intensive care unit had 24 hours of dynamic ECG recordings. Twenty consecutive patients electively admitted for cataract surgery served as a control group and also had recordings. Fifteen (50%) of 30 CVA patients had serious ventricular ectopy, compared with only three (15%) of the 20 control subjects. Among the patients with CVA, two had ventricular tachycardia, two had complete atrioventricular block, and two had asystole, all occurring in CVAs involving the anterior circulation. None of the control subjects experienced these arrhythmias. Cardiac arrhythmias are common in patients with acute CVAs, especially those involving the anterior circulation. Dynamic ECG recordings may detect such arrhythmias and provide data for therapeutic consideration.