Effect of continuing angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers on the day of surgery on myocardial injury after non-cardiac surgery: A retrospective cohort study

Study objective: To evaluate the effect of continuing of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) prescriptions 24 h before surgery on postoperative myocardial injury and blood pressure in patients undergoing non-cardiac surgery. Design: A single-center, retrospective study. Setting: Operating room and perioperative care area. Patients: 42,432 patients who had been taking chronic ACEI/ARB underwent non-cardiac surgery from January 2012 to June 2022. Interventions: Patients who discontinued ACEI/ARB 24 h before surgery (withheld group, n=31,055) and those who continued ACEI/ARB 24 h before surgery (continued group, n=11,377). Measurements: Primary outcome was myocardial injury after non-cardiac surgery (MINS) within 7 days postoperatively. MINS was defined as an elevated postoperative cardiac troponin measurement above the 99th percentile of the upper reference limit with a rise/fall pattern. Perioperative blood pressure and clinical outcomes were secondary outcomes. Main results: Among 42,432 patients, MINS occurred in 2848 patients (6.7%) and was the all-cause of death within 30 days in 122 patients (0.3%). Incidence of MINS was significantly higher in the continued group than the withheld group (847/11,377 [7.4%] vs. 2001/31,055 [6.4%]; OR [95% CI] 1.17 [1.07-1.27]; P<0.001). After 1:1 propensity score matching, 11,373 patients were included in each group. There was still a significant difference for the occurrence of MINS between two groups in matched cohort (7.4% vs. 6.6%, OR [95% CI] 1.14 [1.03-1.26]; P=0.015). Time-average weight of mean arterial pressure <65 mmHg during surgery was significantly higher in the continued group (mean 0.11 vs. 0.09 [95% CI of mean difference] [0.01-0.03]; P<0.001). However, there was no significant difference in other clinical outcomes and mortality. Conclusions: Withholding ACEI/ARB before surgery was associated with a reduced risk of intraoperative hypotension and postoperative myocardial injury, but it did not affect overall clinical outcomes in patients undergoing non-cardiac surgery.