Association between intraoperative hypotension and postoperative myocardial injury in patients with prior coronary stents undergoing high-risk surgery: a retrospective study

We conducted a single-center retrospective study to evaluate the effects of intraoperative hypotension (IOH) on postoperative myocardial injury during major noncardiac surgery in patients with prior coronary stents with preoperatively normal cardiac troponin I levels. Although IOH is assumed to increase the risk of postoperative myocardial injury in patients with prior coronary stents, the level and duration of hazardous low blood pressure have not been clarified. Of 2517 patients with prior coronary stents undergoing noncardiac surgery between January 2010 and March 2017, we analyzed 195 undergoing major surgery (vascular, abdominal, and thoracic surgery) who had a normal preoperative high-sensitivity cardiac troponin I (hs-cTnI) level and were followed up postoperatively within 3 days. Postoperative myocardial injury was defined as a hs-cTnI level greater than the 99th percentile reference value. Primary IOH exposure was defined as a decrease of ≥ 50%, 40%, or 30% from the preinduction mean blood pressure. Additional definition of IOH was absolute mean blood pressure