[Impact of transcatheter aortic valve replacement on renal function in patients with severe aortic stenosis]

Objective: To explore the impact of transcatheter aortic valve replacement (TAVR) on renal function in patients with severe aortic stenosis. Methods: This is a single-center retrospective study. Consecutive patients with severe aortic valve stenosis and received TAVR in Zhongshan Hospital from December 2014 to December 2019 were included. The patients were divided into four groups according to the estimate glomerular filtration rate (eGFR) measured at one day before TAVR, namely eGFR>90 ml·min^-1·1.73m^-2 group, 60-1·1.73m^-2 group, 30-1·1.73m^-2 group and eGFR≤30 ml·min^-1·1.73m^-2 group. The patients were also divided into acute renal function recovery (AKR) group, acute kidney injury (AKI) group and no change in renal function group according to renal function changes at 72 hours after TAVR. AKR was defined as eGFR increased by more than 25% of the baseline value at 72 hours after TAVR, and AKI was defined as eGFR decreased more than 25% of the baseline value at 72 hours after TAVR. The clinical data of each group were compared, and multivariate logistic regression analysis was performed to analyze the determinants responsible for renal function changes after TAVR. Results: A total of 217 patients were enrolled in this study. The age was (76.7±7.4) years and there were 86 females. The Society of Thoracic Surgeons score was (9.5±5.8). The proportions achieved AKR after TAVR were 0, 30.2% (35/116), 58.6% (41/70) and 75.0% (9/12) respectively in eGFR>90 ml·min^-1·1.73m^-2 group, 60-1·1.73m^-2 group, 30-1·1.73m^-2 group and eGFR≤30 ml·min^-1·1.73m^-2 group. A total of 3 patients (1.4%) suffered AKI, including 2 patients in 30-1·1.73m^-2 group and 1 patient in 60-1·1.73m^-2 group. The incidence of AKI in eGFR<60 ml·min^-1·1.73m^-2 group was 2.4% (2/82). Among the 217 patients, AKR occurred in 85(39.2%) patients, 3(1.4%) experienced AKI and renal function remained unchanged in 129 (59.4%) patients post TAVR. Body mass index (BMI), left ventricular end diastolic dimension (LVEDD) and preoperative eGFR were statistically different between the 3 groups (P<0.05). Multivariate logistic regression analysis showed that BMI (OR=5.54, 95%CI 1.04-29.58, P=0.045), preoperative LVEDD (OR=1.22, 95%CI 1.09-1.38, P=0.001) and preoperative eGFR (OR=2.23, 95%CI 2.04-2.55, P=0.004) were associated with non-AKR post TAVR. Conclusions: After TAVR, most patients show no change or improvement of renal function. BMI, preoperative LVEDD and eGFR are related to renal function change after TAVR.