Association of renal regional tissue oxygen saturation and post-procedural acute kidney injury following transcatheter aortic valve implantation

Purpose Acute kidney injury (AKI) is a common complication and a strong risk factor for adverse outcomes after transcatheter aortic valve implantation (TAVI). Renal regional tissue oxygen saturation (rSO ₂ ) reflects tissue perfusion and can be measured using near-infrared spectroscopy. We hypothesized that decrease in renal rSO ₂ during TAVI would predict post-procedural AKI. Methods Patients with severe aortic stenosis who scheduled for transfemoral TAVI were enrolled. Patients undergoing emergent procedures, those with severe renal impairment, those with a distance from skin to renal capsule > 4 cm, those on mechanical ventilation, or those who refused to participate were excluded. The primary outcome was the relationship between changes in renal rSO ₂ during TAVI and post-procedural AKI. AKI was determined according to the Valve Academic Research Consortium-2 criteria. Results Sixty-four patients were included and analyzed. The mean (standard deviation [SD]) age of patients was 82 (4) years, and the median [interquartile range] procedure time was 75 [65–90] min. The incidence of post-procedural AKI was 33% (21/64). There was no difference in the mean (SD) time-weighted renal rSO ₂ (70% [13%] and 73% [11%]), changes in renal rSO ₂ (–14% [10%] and − 15% [13%]), or nadir rSO ₂ (55% [17%] and 60% [17%]) during TAVI between patients who developed post-TAVI AKI and those who did not ( p  = 0.227, 0.157, and 0.333, respectively). In multivariable regression analysis, renal rSO ₂ variables were not predictors of post-TAVI AKI. Conclusion Procedural changes in renal rSO ₂ measured using near-infrared spectroscopy did not predict the development of post-TAVI AKI. Further studies are needed to investigate more effective strategies to predict and prevent AKI following TAVI.