Coronary Angiography Within 48 Hours Before Cardiac Surgery Increases the Risk of Postoperative Acute Kidney Injury

Background: Cardiac surgery and coronary examination, such as invasive coronary angiography (CAG), are both pos-sibly associated with acute kidney injury (AKI). Preoperative CAG examination and cardiac surgery within a short interval may increase the incidence of AKI. Methods: We retrospectively reviewed 1112 patients who underwent CAG examination within 30 days prior to the car-diac operation in this study. Postoperative AKI was defined, according to Kidney Disease Improving Global Outcomes Definition and Staging (KDIGO) criteria. Results: The total incidence of AKI was 40.8% and cys-tatin C level was 1.260 (1.028, 1.672) mg/L. For patients who received CAG, age, body mass index, cardiopulmonary time, and the time interval between preoperative CAG examina-tion and cardiac operation within 48h was shown to be inde-pendent predictors of postoperative AKI. The incidence of AKI in patients undergoing preoperative CAG within 48h was 11.2% higher than in those more than 48h (P < 0.001). Patients undergoing valve surgery with or without coronary artery bypass grafting (CABG) exhibited a higher AKI risk than those only accepting CABG. The in-hospital stay of patients who developed AKI was 2 days longer than those without AKI. However, undergoing CAG within 48h prior to cardiac operation did not prolong ICU length of stay or hospital length of stay, nor did it increase the risk of death or renal failure after an operation. Conclusion: Undergoing CAG within 48 hours before cardiac surgery increases the risk of postoperative AKI.