Non-obstructive mesenteric ischemia: a potentially lethal complication after cardiovascular surgery: report of two cases.

We report two cases of non-obstructive mesenteric ischemia (NOMI), a rare but potentially lethal complication after cardiovascular surgery, which was successfully managed. In both cases (a 74-year-old chronic hemodialysis patient who underwent emergency aortic valve replacement and coronary artery bypass graft (CABG), and a 74-year-old patient who underwent emergency abdominal aortic aneurysm operation), NOMI occurred early postoperatively (on day 8 and 22, respectively). They suffered from severe abdominal pain, confusion, and metabolic acidosis. Contrast-enhanced multi-detector CT (MDCT) scan and subsequent selective mesenteric angiography revealed characteristic signs of NOMI, for which selective papaverine infusion through the angiography catheter was performed. It was effective in both cases to halt progressive bowel ischemia and bided our time to perform a hemicolectomy of the necrotic segment. Contrast-enhanced MDCT scan and subsequent selective angiography are vital for diagnosis. If the condition does not improve after selective papaverine infusion, exploratory laparotomy and resection of necrotic intestinal segment should be performed immediately.