ABSTRACT

Advances in cardiac surgery over the past decades have enabled more efficient, complex and successful repairs of cardiac injuries. Cardiac injuries may be caused by blunt, penetrating or iatrogenic trauma. 25% of the trauma related deaths are caused by chest trauma. The lethal nature of this injury is due to the high concentration of major vascular and visceral structures within the mediastinum. The most common cause of blunt cardiac injury is high impact motor vehicle accidents. Other sources of blunt cardiac trauma are falls from heights, crush injuries and athletic injuries. Only 5% of these patients would receive medical intervention. Blunt trauma causes pericardial and epicardial hemorrhage and myocardial contusion. Myocardial contusion may range in severity from minor subepicardial hematoma to larger extravasations including the full thickness of the myocardium. Larger contusions lead to necrosis which may heal by scarring or may lead to lethal rupture of the myocardium. Rupture in the ventricles, atria, atrioventricular septum and pulmonary veins can be seen. Rupture in papillary muscles may lead to acute mitral or tricuspid failure. Fistulization, laceration and thrombosis in the coronary arteries may lead to further myocardial injury necessitating coronary artery bypass surgery. Patients with blunt cardiac trauma, either symptomatic or asymptomatic, should be monitored closely for possible complications of myocardial contusion. Penetrating cardiac injuries may be caused by gunshot wounds or stab wounds. Iatrogenic injuries may be encountered most commonly during catheterisation procedures and reoperations due to excessive adhesions caused by previous operations. Major factor affecting survival of these patients is the duration of transport from the scene of trauma to the medical center for interventions. Patients with prominent signs of cardiac tamponade should be taken into the operating room promptly and treated without necessitating further diagnostic tools. Emergency thoracotomy or sternotomy may be instituted to decompress the heart and control possible hemorrhage. In severe hypovolemic shock, emergency sternotomy may be performed before placement of intravenous lines and volume replacement with crystalloids, colloids and blood can be administered directly into the right atrium through large bore needles. Simple injuries may be repaired primarily with careful monitoring and stabilization of hemodynamics. In cases of larger defects or complex injuries such as valvular disruption and acute failure, injury of coronary arteries necessitating coronary artery bypass surgery and atrioventricular septal defects, cardiopulmonary bypass may be used to avoid further myocardial injuries. Close monitoring of asymptomatic cardiac trauma patients for at least 48 to 72 hours after admission for possible complications and aggressive and rapid intervention in patients with manifest symptoms are vital for survival and effective treatment of cardiac injuries. (JAREM 2014; 2: 45-8)