Acute kidney injury following transcatheter aortic valve implantation: incidence, predictors and clinical outcome.

Background: Limited data exist on renal complications of transcatheter aortic valve implantation (TAVI) within a comprehensive program using different valves with transfemoral, transapical, and trans-subclavian approach.

Methods: Prospective single-center registry of 102 consecutive patients undergoing TAVI using both approved bioprostheses and different access routes. The main objective was to assess the incidence, predictors and the clinical impact of acute kidney injury (AKI). AKI was defined according to the valve academic research consortium (VARC) indications.

Results: Mean age was 83.7 ± 5.3 years, logistic EuroSCORE 22.6 ± 12.4%, and STS score 8.2 ± 4.1%. Chronic kidney disease at baseline was present in 87.3%. Periprocedural AKI developed in 42 patients (41.7%): 32.4% stage 1, 4.9% stage 2 and 3.9% stage 3. The incidence of AKI was 66.7% in transapical, 30.3% in transfemoral, and 50% in trans-subclavian procedures. The only independent predictor of AKI was transapical access, with a hazard ratio (HR) between 4.57 and 5.18 based on the model used. Cumulative 1-year survival was 88.2%. At Cox regression analysis, the only independent predictor of 30-day mortality was diabetes mellitus (HR 7.05, 95% CI 1.07-46.32; p=0.042), whilst the independent predictors of 1-year death were baseline glomerular filtration rate<30 mL/min (HR 5.74, 95% CI 1.42-23.26; p=0.014) and post-procedural AKI 3 (HR 8.59, 95% CI 1.61-45.86, p=0.012).

Conclusions: TAVI is associated with a high incidence of AKI. Although in the majority of the cases AKI is of mild entity and reversible, AKI 3 holds a strong negative impact on 1-year survival. The incidence of AKI is higher with transapical access.