Background: Previous studies demonstrated that acute kidney injury (AKI) after transcatheter aortic valve implantation (TAVI) is frequent and associated with adverse outcomes. These studies however applied only serum creatinine (sCr) criteria while discarding urine output criteria. We hypothesized that adding urinary output criteria might contribute to early AKI diagnosis
Methods: We included 104 patients with severe aortic stenosis who underwent a TAVI procedure between December 2012 and September 2013. Urinary output was assessed hourly for at least 24 hours following TAVI, and sCr was assessed at least daily until discharge. Based on the Valve Academic Research Consortium (VARC), AKI was determined using the AKI network classification (AKIN) including Scr and urine output criteria. We compared the incidence of AKI and time to AKI diagnosis based on the two AKIN methods.
Results: The mean age was 82 + 9 years (range 61-94) and 47% were male. AKI occurred in 20 patients (19 %), 15 of whom (14.5%) had AKI defined by Scr criteria. Ten (9.6%) patients had AKI defined by urinary output criteria, only 5 of whom had AKI defined also by sCr criteria, while in the other 5 patients no significant changes in sCr were observed throughout hospitalization. The use of urinary output criteria resulted in earlier identification of AKI (12.2 vs.31.6 hours, p=0.001) and was associated with lower Scr elevation in patients having AKI defined by only urinary output criteria (0.12 vs 0.42 mg/dl, p=0.028).
Conclusion: Among patients undergoing TAVI the implication of AKIN urine criteria enables earlier identification of AKI, thus allowing early interventions to prevent further renal impairment.
