False negative of pericardial effusion using focused assessment with sonography for trauma and enhanced CT following traumatic cardiac rupture; A case report

BACKGROUND: The focused assessment with sonography for trauma (FAST) examination is helpful for the identification of pericardial effusion in trauma. However, in a cardiac rupture with a pericardial perforation, pericardial effusion is not always detected by FAST. We experienced the case that FAST and enhanced CT failed to detect pericardial effusion. CASE PRESENTATION: A 51-year old woman injured after falling from a height of 3 m was brought to our institute. Focused assessment with sonography for trauma and enhanced computed tomography did not reveal any pericardial effusion; however, a massive hemothorax was revealed. Because the patient's hemodynamic state had become unstable, we performed an urgent left anterolateral thoracotomy. A left pericardial perforation was detected. By performing a clamshell thoracotomy, we found a rupture of 1 cm in diameter at the left atrial appendage. The hemodynamic state was stabilized by suturing the injury site. The postoperative course was uneventful, and the patient was transferred to another hospital after 31 days of admission. CONCLUSIONS: Cardiac injury in the left atrial appendage is rare and sometimes difficult to diagnose and to repair. In the case of a blunt chest trauma with a massive hemothorax, although focused assessment with sonography for trauma gives negative results for pericardial effusion, a cardiac rupture with pericardial perforation should be considered.