Effect of Elapsed Time From Coronary Angiography Until Off-Pump Coronary Artery Bypass Surgery on Postoperative Renal Function

Abstract

Background: A new concern in acute kidney injury (AKI) following coronary artery bypass grafting (CABG) is the elapsed time from coronary angiography (CAG) until subsequent surgery. This study aimed to retrospectively evaluate renal function following elective off-pump CABG (OPCAB). Methods and Results: Three hundred and seven patients were divided either into group A (elapsed time between CAG and surgery ≤5 days, n=138) or B (elapsed time >5 days, n=169). The estimated glomerular filtration rate (eGFR) was obtained on the 1st, 3rd and 7th day following CABG. The pre-, intra-and postoperative relevant data were analyzed. 51 patients (16.6%) developed postoperative AKI. Patients with shorter elapsed time were more likely to present postoperative AKI than those with a longer elapsed time (23.9% vs. 10.7%, P=0.003). Multivariate logistic regression analysis showed that elapsed time had an independent influence on the development of postoperative AKI (odds ratio 2.35, 95% confidence interval 1.45-5.26, P=0.009). The eGFR reduced gradually after surgery, dropped to a minimum within 3 days, and then increased slowly in both groups. Minimum eGFR following surgery in group B was significantly higher than that in group A (64.3±6.5 ml/min vs. 59.2±9.3 ml/min, P<0.0001). Conclusions: Beginning OPCAB early after CAG did affect postoperative renal function and increased the incidence of AKI.