Abstract 14658: Echocardiographic Metrics Before Coronary Artery Bypass Grafting Are Associated With Postoperative Kidney Injury in Patients With Preserved Ejection Fraction, and Mean Perfusion Pressure May Mediate This Relationship

Abstract

Introduction: Preserved left ventricular ejection fraction (LVEF) patients often suffer acute kidney injury (AKI) after coronary-artery bypass surgery (CABG). We studied the relationship of relative wall thickness (RWT) and LV filling pressure (E/e’), measured by preoperative transthoracic echocardiogram (TTE), with AKI in this population. As these markers may identify subclinical cardiac dysfunction, we also examined the role of intraoperative hypotension by mean perfusion pressure (MPP). Hypothesis: Are LV RWT and E/e’ from preoperative TTE associated with post-CABG AKI in preserved LVEF patients? Are LV RWT and E/e’ associated with hemodynamic instability measured by total minutes of MPP (MAP-CVP) < 60mmHg (1 min. resolution)? Aims: We aim to identify novel preoperative TTE markers that provide mechanistic insight (low MPP) to AKI development in preserved LVEF patients undergoing CABG. This could lead to interventions during high-risk surgeries to reduce AKI. Methods: We accessed 1343 patient records and used multivariate logistic regression models adjusted for covariates (Fig. 1). Results: Mean (SD) age was 65 (10). 170/709 patients had AKI. RWT and E/e' are weakly correlated (r=.15, p=.0075, n=314). Each E/e’ increase associated with AKI, OR 1.11 (1.04-1.19, p=.003). Every 0.1 RWT increase associated with AKI, OR 1.21 (1.02-1.43, p=.031, n=518). Each minute MPP < 60mmHg associated with 0.6% AKI increase (n=714). E/e’ associated with low MPP; RWT did not. Conclusion: In preserved LVEF patients, RWT and E/e’ are associated with higher AKI risk after CABG. E/e’ is also associated with intraoperative MPP<60mmHg, which may partially mediate the E/e’-AKI relationship.