Intrathoracic Gastric Volvulus Mimicking a Cardiopulmonary Emergency: An Unusual but Fatal Diagnostic Pitfall in Critical Care.

Hiatal hernias are often incidental findings, yet acute intrathoracic gastric volvulus in large hernias can rapidly evolve into catastrophic cardiopulmonary collapse. We report the case of a 65-year-old man presenting with progressive dyspnea and retrosternal pain who deteriorated into hypoxemic respiratory failure and shock. Despite initial stabilization with high-flow oxygen, fluid resuscitation, and vasopressor support, he remained hemodynamically unstable. Chest computed tomography revealed a massive sliding hiatal hernia complicated by organoaxial gastric volvulus occupying the left hemithorax with mediastinal shift and lung compression. Within hours, the patient developed sudden neurological decline and refractory shock, progressing to pulseless electrical activity despite resuscitative efforts. This case underscores intrathoracic gastric volvulus as a rare but fatal mimic of primary cardiopulmonary emergencies in the critical care setting, emphasizing the need for early imaging and urgent surgical assessment when clinical severity exceeds pulmonary findings.