A hidden tear: Survival following blunt right atrial appendage rupture without external chest trauma

Blunt cardiac chamber ruptures are rare and often fatal. These injuries are typically associated with overt chest trauma, making their diagnosis difficult when external signs are absent.

We report the case of a 17-year-old male who sustained a right atrial appendage rupture with pericardial tamponade after a high-speed auto-versus-pedestrian collision. There was no evidence of chest injury, including rib fractures, upon presentation. The initial assessment revealed hemodynamic instability and a positive Focused Assessment with Sonography for Trauma (FAST) exam in the right upper quadrant, with equivocal pericardial space findings, prompting emergent exploratory laparotomy and pericardial window. Upon decompression of a significant pericardial effusion, cardiothoracic surgery identified and repaired a 2 cm defect of the right atrial appendage via emergent median sternotomy. The patient recovered well following surgical intervention and was discharged home on hospital day 12.

This case highlights the diagnostic challenge of blunt cardiac injury in the absence of apparent external chest trauma. It emphasizes the importance of maintaining a high index of suspicion for occult cardiac injury in patients with unexplained hypotension following high-energy mechanisms, even when chest imaging and exam findings are discordant. Early surgical intervention remains critical for survival in these rare but potentially survivable injuries.