[A case of acute hemorrhagic gangrenous acalculous cholecystitis with bile peritonitis during anti-coagulant therapy after coronary-artery bypass grafting].

Acute acalculous cholecystitis is a relatively rare complication occurring after surgery on organs other than the bile duct system. It is often misinterpreted to be a post-operative symptom, and can progress into a very serious condition with high risk of mortality if gangrene and perforation develop. Its occurrence after open heart surgery is relatively rare. We experienced a case of acute hemorrhagic, gangrenous acalculous cholecystitis that developed after coronary-artery bypass grafting. The patient, a 78-year-old man, complained post-operatively of a right upper abdominal pain. The diagnosis of acute gangrenous acalculous cholecystitis was established on the basis of abdominal sonography and CT, and emergency operation performed was successful. Etiological factors in this case may have included post-operative stasis of bile, swelling of the gallbladder, hypotension during cardiopulmonary bypass, and post-operative anti-coagulant therapy administered after open heart surgery. These factors induced intracystic hemorrhage followed by sudden exacerbation, which resulted in gangrenous cholecystitis followed by perforative biliary peritonitis.