DOCUMENTATION of human cerebral electrical activity at the time of cardiac arrest is rarely available. During a recent case of emergency carotid endarterectomy, a 27-s period of ventricular asystole occurred. Cerebral electrical activity was lost within 15 s of asystole and returned almost instantly on resuscitation. This case is presented because complete documentation of physiological measurements for the period before, during, and immediately after the patient's cardiac arrest was available. <h3>Report of a Case</h3> The patient was a 62-year-old woman with a history of syncopal episodes for several months. Two days before surgery, she sustained an apparent stroke resulting in right-arm paralysis. Angiography disclosed severe left internal carotid artery stenosis. Preoperative ECGs showed evidence of intermittent anterolateral subendocardial ischemia. Because of progressive neurological deterioration, an emergency carotid endarterectomy was performed. Following insertion of intravenous (IV), radial, and pulmonary artery catheters and application of EEG and ECG monitors (including precordial leads),