Association between Continuous Peri-procedural Use of ACE Inhibitors or ARBs in Patients with AKI Undergoing Cardiac Catheterization Bin Hu, M.D, Usman A. Khan, M.D, and Erdal Sarac, M.D., F.A.C.P., F.A.S.N. Department of Internal Medicine, St. Elizabeth Health Center, Youngstown, Ohio Introduction To determine if pre-procedural and earlier resumption of angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) therapy in AKI (Acute kidney injury) patients receiving cardiac catheterization is associated with long-term reno-protection and improvement in survival. Method A retrospective study of 345 patients undergoing cardiac catheterization with an admitting diagnosis of acute kidney injury was conducted. Baseline data collection included patient characteristics, peri-catheterization variables, and medications. Serum creatinine values were recorded for every patient throughout the hospital stay. We defined AKI recovery as the improvement between initial serum creatinine and the serum creatinine at discharge. Additional secondary clinical outcomes were in-hospital mortality, dialysis initiated during the hospital stay, and patient disposition (DNR or hospice). Results Of the 345 patient with AKI undergoing cardiac catheterization, 88 patients used ACEi/ARB before admission. Most patients in this study (71/88), exhibited kidney function resumption or improvement at hospital discharge. No differences in pre-catheterization characteristics, including comorbidities and medications, were noted. Pre-catheterization serum creatinine levels exhibited no significant differences between patients on whom medications were continued and held. Similarly, there were no significant differences in peak creatinine levels or creatinine levels at between these two groups. Discussion  In this study, there was no evidence that continued preoperative ACEi/ARB administration resulted in worsening AKI, as evidenced by improvement in most of the patient’s serum creatinine post-catheterization. Thus, the clinical significance of AKI in patients on ACEi/ARBs undergoing cardiac catheterization is unclear. Future studies should assess optimal strategies for administration of these medications in the perioperative setting. Conclusion While some guidelines have recommended discontinuation of ACEi/ARB temporarily during AKI, kidney function recovery did not differ in the current series of patients who either continued taking ACEi/ARB or discontinued these medications prior to the procedure. Thus, pre-catheterization discontinuation of ACEi/ARB may be unnecessary. References   Shah M, Jain AK, Brunelli SM, et al. BMC Nephrology 2014, 15-53. Bakris GL, Weir MR. Arch Intern Med. 2000 Mar 13;160(5):685-93. Testani JM, Kimmel SE, Dries DL et al. Circ Heart Fail 2011 Nov;4(6):685-91. Mangrum AJ, Bakris GL. Semin Nephrol 2004 Mar;24(2):168-75. Coca SG, Garg AX, Swaminathan MS, et al. Nephrol Dial Transplant. 2013 Sep 28: 2787-2799.