Spiked helmet pattern ST elevation in subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is occasionally associated with the electrocardiographic (ECG) pattern of ST-segment elevation myocardial infarction (STEMI). Missing the true clinical diagnosis can result in inappropriate and harmful interventions. We report the case of a 40-year-old female who was found down. The ECG was diagnostic for acute lateral STEMI. Further analysis of the ECG showed marked prolongation of the QT interval and the "spiked helmet sign" (SHS). The patient was ruled out for myocardial infarction and a head CT demonstrated a massive SAH with acute hemorrhage into the ventricles. Review of the literature and of our own ECG files revealed additional cases where severe acute central nervous system (CNS) conditions were associated with the SHS.