The efficiency of remote ischemic preconditioning on serum cystatin C-based acute kidney injury in patients undergoing coronary angiography; a randomized controlled trial

Introduction: Contrast-induced acute kidney injury (CI-AKI) is a known complication of cardiac interventions. Remote ischemic preconditioning (RIPC) is a non-pharmacological method which has a nephroprotective effect. Serum cystatin C (CysC) is a suitable biomarker for the early diagnosis of AKI. Objectives: This study aimed to evaluate the incidence of CI-AKI after RIPC in patients undergoing coronary angiography, through assessment of CysC. Patients and Methods: Around 140 patients with stable coronary artery disease undergoing angiography were randomly allocated to two groups of RIPC and control groups. In each group, the following biomarkers were assessed: serum creatinine (Cr) and CysC at baseline, 24-hour and 48-hour serum Cr and 24-hour CysC. The endpoint was the development of AKI based on either the KDIGO criteria or a 15% increase in serum CysC. Results: No significant difference was observed between two groups regarding the incidence of AKI according to either KIDIGO criteria or by the increase of serum CysC (P =0.116 and P =0.392, respectively). Moreover, a 46.99% increase in CysC level was observed among patients with AKI during the first 24 hours after the procedure, while at the same interval, it increased only 16.01% in patients without AKI. Conclusion: RIPC with three cycles of 5-minute ischemia and 5-minute reperfusion, did not decrease serum CysC based CI-AKI or alter renal biomarkers course in patients with low risk, who underwent coronary angiography.