We describe computed tomographic (CT) findings in two patients with cardiac injury who required emergency surgery. Chest CT revealed an unexpected low-density area, indicating pericardial effusion. We emphasize that, given the situation of trauma, an incidental low-density area covering more than two slices along the inferior border of the heart suggests pericardial effusion, which may be caused by cardiac injury.
Cardiac injury due to trauma has a high mortality rate. In a study of 102 patients with cardiac injury, only 10.8% of patients reached hospital alive (1). We describe the computed tomographic (CT) findings in two patients with cardiac injury who required emergency surgery.
CASE REPORTS
Case 1A 16-year-old man was severely injured in a traffic accident when he collided with a truck while riding on a motorbike. He was immediately transferred to our hospital. Initial clinical assessment showed a decreased level of consciousness and shock. After receiving intravenous fluid replacement and pressure agent, he recovered rapidly.Plain chest radiography showed mild cardiomegaly and dilatation of the azygos vein without any evidence of pneumothorax or widening of the upper mediastinum (Fig. 1A). CT demonstrated a low-density area on sIices of the inferior border of the heart and just above the diaphragm (Fig. 1B and C). A low-density area on three contiguous slices indicated pericardial effusion. An echocardiogram confirmed a small amount ofpericardial effusion.Subsequent pericardiocentesis failed to aspirate blood. Immediately after pericardiocentesis, cardiac arrest suddenly occurred. Emergency thoracotomy was performed. There was massive pericardial effusion. The cardiac surgeon found a tear in the right atrium, right ventricle, and left ventricle. The rupture in the right atrium was the largest and was considered to be the main cause of pericardial effusion. The tears were repaired surgically. Although aggressive treatment was continued in the intensive care unit, the patient died 5 days after the surgery, owing to disseminated intravascular coagulation and multiple organ failure.
Case 2A 38-year-old man was stabbed in the chest and abdomen with a 27-cm-long knife in a street fight. He was alert upon admission, although his systolic blood pressure was approximately 70 mmHg. His blood pressure returned to normal after intravenous fluid replacement.Plain chest radiography detected a mass shadow in the shape of a teardrop in the left lower lung field, suggesting a penetrating injury of the pulmonary parenchyma. The overall radiolucency of the left lung was decreased, suggesting the presence of a large amount of pleural effusion. The contour
• Pericardial Effusion in Cardiac TraumaEmergency Radiology °