Clinical features and outcomes of nonocclusive mesenteric ischemia after cardiac surgery: a retrospective cohort study.

Nonocclusive mesenteric ischemia after cardiac surgery is a life-threatening complication requiring emergent intervention. However, because of its rarity, the clinical features and outcomes of nonocclusive mesenteric ischemia remain unknown. The present study aimed to clarify patients' backgrounds, clinical features and mortality of nonocclusive mesenteric ischemia after cardiac surgery, using a Japanese national inpatient database. We identified patients undergoing cardiac or thoracic aortic surgery between July 2010 and March 2017, using the Japanese Diagnosis Procedure Combination database. We calculated the incidence proportion of nonocclusive mesenteric ischemia and examined treatment options (bowel resection and interventional radiology) and patients' discharge status (in-hospital mortality and destination of discharge). We identified 221,900 eligible patients to find 568 (0.26%) patients with bowel ischemia in the same admission. Of these, 124 (0.06%) patients developed nonocclusive mesenteric ischemia, and in-hospital mortality after nonocclusive mesenteric ischemia was 77%. Treatment options for nonocclusive mesenteric ischemia included bowel resection alone (n = 34), interventional radiology (n = 15), or both (n = 15); 27, 10, and 8 patients died, respectively. Seven patients (5.6%) were discharged to home. Among 60 patients without bowel resection or interventional radiology, 50 patients died. In multivariable regression analysis, older age, preoperative hemodialysis, preoperative circulatory support, and hypothermic cardiopulmonary bypass were associated with NOMI. The present study showed that nonocclusive mesenteric ischemia after cardiac surgery was very rare. Mortality following nonocclusive mesenteric ischemia was very high even if patients underwent bowel resection or interventional radiology.