Significant ECG findings frequently accompany blunt chest trauma. Surface ECG in conjunction with creatinine phosphokinase (CPK) isoenzyme assay, has been an accepted standard for diagnosis of posttraumatic cardiac dysfunction, or "cardiac contusion." Studies employing recently developed noninvasive cardiac imaging techniques have called this practice into question and have shed new light on the pathophysiology of this clinical entity. As a result, it is appropriate to review the ECG manifestations of blunt chest trauma and to reappraise the utility of the ECG in its evaluation. This article will concern itself solely with nonpenetrating cardiac injuries not requiring initial surgical management, since clinical presentation, course, and prognosis differ when operative therapy is indicated.