The Significance of Hypothermia in Preserving Ischemic Myocardium

A 57-year-old male immigrant was being driven to the emergency department (ED) of a nearby hospital because of substernal pressure and pain, 1 hour in duration. While getting out of the car he suddenly collapsed; an ED nurse was immediately summoned and determined that the patient was in cardiac arrest. Cardiopulmonary resuscitation was immediately initiated and he was promptly electrically defibrillated. Total time from onset of cardiac arrest to return to cardiac function was estimated to be no greater than 3½ minutes. The electrocardiogram after defibrillation revealed an acute anterior myocardial infarction with 6-mm “J” point elevation in leads V₁ to V₄ and 4-mm elevation in leads V₅ and V₆. Elevation of “J” point was also noted in leads I and aVL with reciprocal depression in leads II, III, and aVF. The ED was equipped to perform therapeutic hypothermia and elected to apply whole body...