ABSTRACT: Background Postoperative clinical outcomes associated with the preoperative continuation or discontinuation of angiotensin-converting enzyme inhibitors ( ACEIs ) or angiotensin receptor blockers ( ARBs ) before cardiac surgery remain unclear. Methods and Results In a single-center, open-label, randomized, registry-based clinical trial, patients undergoing nonemergent cardiac surgery were assigned to ACEI / ARB continuation or discontinuation 2 days before surgery. Among the 584 patients screened, 261 met study criteria and 126 (48.3%) patients were enrolled. In total,121 patients (96% adherence; 60 to continuation and 61 to ACEI / ARB discontinuation) underwent surgery and completed the study protocol, and follow-up was 100% complete. Postoperative intravenous vasopressor use (78.3% versus 75.4%, P=0.703), vasodilator use (71.7% versus 80.3%, P=0.265), vasoplegic shock (31.7% versus 27.9%, P=0.648), median duration of vasopressor (10 versus 5 hours, P=0.494), and vasodilator requirements (10 versus 9 hours, P=0.469) were not significantly different between the continuation and discontinuation arms. No differences were observed in the incidence of acute kidney injury (1.7% versus 1.6%, P=0.991), stroke (no events, mortality (1.7% versus 1.6%, P=0.991), median duration of mechanical ventilation (6 versus 6 hours, P=0.680), and median intensive care unit length of stay (43 versus 27 hours, P=0.420) between the treatment arms. Conclusions A randomized study evaluating the routine continuation or discontinuation of ACEIs or ARB s before cardiac surgery was feasible, and treatment assignment was not associated with differences in postoperative physiological or clinical outcomes. These preliminary findings suggest that preoperative ACEI / ARB management strategies did not affect the postoperative course of patients undergoing cardiac surgery. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT 02096406.
