Updates on the risk factors of acute kidney injury after transcatheter aortic valve replacement

We agree with Onuigbo and Agbasi that previous studies have attempted to identify effective interventions to prevent postoperative acute kidney injury (AKI) events including cardiac surgery-associated AKI and most of them failed to be successful (1,2). In the setting of transcatheter aortic valve replacement (TAVR), we recently performed a comprehensive review of available data on incidence and risk factors of AKI after TAVR (3). We demonstrated that causes of AKI following TAVR are likely multifactorial including hypotension during rapid ventricular pacing for balloon valvuloplasty and valve deployment, use of contrast agents, and embolization resulting from the manipulation of catheters in the aorta of patients with diffuse atherosclerosis (4-6). However, we found that the data on effects of transapical (TA) vs. transfemoral (TF) approaches, contrast media and blood transfusion on AKI following TAVR were still controversial. Thus, we performed additional studies to evaluate these effects on AKI after TAVR, and ultimately to prevent AKI. We recently conducted a meta-analysis of 17 cohort studies with 5,085 patients assessing the risk of AKI in patients undergoing TA-TAVR vs. TF-TAVR (7). We found a