Hydropneumopericardium presenting as an acute coronary syndrome: a rare complication of paraesophageal hernia.

Hydropneumopericardium is a very rare complication of long-standing paraesophageal hernia, occurring as a result of rupture of the intrathoracic gastric volvulus into the pericardium. A chronic paraesophageal hernia that is complicated by gastric volvulus can develop into such surgical emergencies as acute gastric obstruction, strangulation, perforation, and rupture into adjacent structures. Subsequent hydropneumopericardium constitutes an acute emergency that requires immediate surgical treatment and pericardial drainage.