Pictured are Cerebral T waves which can be seen in subarachnoid hemorrhage. Subarachnoid hemorrhage can cause changes on the EKG such as deep t wave inversions or ST elevation.   ECG Findings of Cerebral T Waves   Inverted, wide T waves are most notable in precordial leads (can be seen in any lead).  QT interval prolongation.   Pearls   These are associated with acute cerebral disease, most notably an ischemic cerebrovascular event or subarachnoid hemorrhage.  They may be accompanied by ST segment changes, U waves, and/or any rhythm abnormality.  Differential diagnosis includes extensive myocardial ischemia.  Strongly suspect an intracranial etiology in a patient with altered mental status and these electrocardiographic findings. (Atlas of EM)