開心術後非閉塞性腸管虚血と思われた原発性小腸軸捻転症

Primary Volvulus of the Small Intestine Mimicking Nonocclusive Mesenteric Ischemia Following Open-heart Surgery

成人例での原発性小腸軸捻転症は非常にまれである．絞扼性イレウスに比して経過は緩やかであるが，治療介入が遅れると致死的である．われわれは，開心術後加療中に非閉塞性腸管虚血と思われた原発性小腸軸捻転症を経験したので，文献的考察を加えて報告する．

A 73-year-old female who underwent aortic valve replacement with a biological valve, coronary artery bypass, and left atrial appendage closure had sudden onset of nausea and abdominal pain 43 days after surgery. She had a history of nonocclusive mesenteric ischemia on 4th postoperative day, for which conservative management was successfully carried out. A contrast-enhanced computed tomography （CT） was performed because a recurrence of nonocclusive mesenteric ischemia was suspected. It revealed a whirl sign in the small intestine, suggestive of small intestine volvulus. At the subsequent emergency laparotomy, volvulus caused severe congestion in the small intestine, aproximately 40 cm from the cecum. However, there was no evidence of transmural necrosis, and reduction of torsion notably improved blood supply to the small intestine. Her regular diet was resumed on 4th postoperative day, and her postoperative course was uneventful. Volvulus should be considered as a differential diagnosis in the setting of acute abdominal pain after open-heart surgery.