Effect of angiography timing on acute kidney injury after cardiac surgery in patients with preoperative renal dysfunction

BACKGROUND: Cardiac surgery-associated acute kidney injury (AKI) is one of the common complications of cardiac surgery. Preoperative angiography helps assess heart disease but may increase the risk of AKI. Although more and more patients with preoperative renal dysfunction can undergo cardiac surgery with the advances in surgical techniques, there is little research on the effect of angiography on postoperative AKI in these patients. This study investigates whether angiography increases the risk of AKI after cardiac surgery in patients with preoperative renal dysfunction (15 ≤ eGFR < 60 ml/min/1.73m(2)). METHODS: Patients with preoperative renal dysfunction (15 ≤ eGFR < 60 ml/min/1.73m(2)) who underwent angiography and cardiac surgery successively from January 2015 to December 2020 were retrospectively enrolled in this study. The primary outcome was postoperative AKI, defined as the Kidney Disease: Improving Global Outcomes Definition and Staging (KDIGO) criteria. Univariate analysis and multivariate regression were performed to identify the association between angiography timing and AKI. RESULTS: A total of 888 consecutive eligible patients with preoperative renal dysfunction (15 ≤ eGFR < 60 ml/min/1.73m(2)) were enrolled in this study. The incidence of AKI was 48.31%. Male (OR = 1.903), the interval between angiography and surgery (0-2d OR = 2.161; 3-6d OR = 3.291), cross-clamp duration (OR = 1.009), were identified as predictors for AKI. The interval between angiography and surgery was also associated with AKI in the patients with 15 ≤ eGFR < 30ml/min/1.73m(2) (0-2d OR = 4.826; 3-6d OR = 5.252), 30 ≤ eGFR < 45 ml/min/1.73m(2) (0-2d OR = 2.952; 3-6d OR = 3.677), but not associated with AKI in patients with 45 ≤ eGFR < 60 ml/min/1.73m(2). CONCLUSIONS: In patients with preoperative renal dysfunction, the interval between angiography and cardiac surgery (0-2d and 3-6d) was associated with AKI. For patients with poorer preoperative renal function, the interval between angiography and cardiac surgery is of great concern.