Objective To investigate whether stent implantation before cardiac surgery with cardiopulmonary bypass (CPB) have any effect on the development of impaired renal function in patients with renal artery stenosis (RAS).
Methods In this retrospective study, 69 patients with RAS were included, among whom there were 38 patient receiving renal artery stent implantations just before CPB. To assess acute kidney injury (AKI) after CPB, serum urea nitrogen (SUN), serum creatinine (SCr), creatinine clearance (CrCl) were recorded at baseline, at the end of operation, during the 1st and 2nd postoperative 24 h. Patients with abnormal SCr (>106 μmol/l) before cardiac surgery were not included in this study.
Results Baseline characteristics were similar between groups. Changes of SUN, SCr and CrCl were similar between groups. The incidences of AKI (22.6%, 26.3%) in patients without or with stent implantation were not significantly deferent from each other. In patients without stent implantation, AKI defined by RIFLE occurred in 7 (22.6%) patients: 5 (16.1%) with class R, 2 (6.5%) with I, and no patients with F. In patients with stent implantation, 10 patients (26.3%) had an episode of AKI during hospitalisation: 6 (15.8%) had RIFLE-R, 4 (10.5%) had RIFLE-I, and no patients had RIFLE-F.
Conclusion There is no data suggesting that stent implantation can improve the renal dysfunction after CPB. However, it cannot be concluded that RAS is not associated with AKI after CPB.