Background: MI is a rare complication of trauma. We anticipate that the aging of the population and the concomitant rise in geriatric trauma will result in an increase in acute illnesses of the elderly (such as MI) complicating recovery from injury . The purpose of this article is to define the presentation of MI in the immediate postinjury period. Study Design: Medical records of all trauma patients in whom MI developed during their hospitalizations at a single Level I trauma center, the Barnes Hospital/Washington University Medical Center, between 1990 and 1999 were screened through the trauma registry. Nineteen patients with possible postinjury MI were identified. Of these, five had bona fide cases of postinjury MI, five had ambiguity about whether MI preceded or followed trauma, one had an MI resulting in trauma, and eight were excluded because they did not meet strict diagnostic criteria for MI. Results: The five patients with posttraumatic MI were older than the general trauma population with ages ranging from 51 to 81 years (mean ± SD = 72 ±14 years). Each had preexisting medical illnesses, some of which are recognized to predispose to coronary artery disease. There were no identifiable precipitants other than the recent injury. Importantly, only one of the five patients had chest pain as a presenting symptom and each of the five cases was complicated by acute congestive heart failure. Conclusions: MI remains a rare but important complication of injury and may increase owing to the changing demographics of trauma victims. Methods for thorough history-gathering to identify preexisting conditions, for early hemodynamic monitoring and anticoagulation for MI in the setting of trauma, and for identifying preexisting conditions should be defined. The presentation of MI in the setting of injury is a typical and complications are frequent. (C) 2000 American College of Surgeons.