Includes bibliographical references.The vast majority of patients with penetrating cardiac injuries do not reach the hospital alive as the pre-hospital mortality rate for these injuries is in the region of 86%. The patients that do reach the hospital alive are potential survivors and it is obviously crucial that any cardiac injury is detected and managed appropriately. Most of these injuries present with either cardiac tamponade or hypovolaemic shock and are relatively straightforward to diagnose and require immediate surgery. There is, however, a group of patients that are relatively stable with an underlying cardiac injury and it is in these patients that a potential or occult cardiac injury needs to be identified