Several predisposing factors of CSA-AKI have been identified, such as cardiovascular and pulmonary diseases, nephrotoxic agents (i.e., nonsteroidal anti-inflammatory drugs, inhibitors of the renin-angiotensin system, X-ray contrast agents), and prolonged cardiopulmonary bypass (CPB) and aortic clamp time [6]. Here, REN is linked to acute kidney injury.