Mas-Peiro S, Faerber G, Bon D, et al. - Researchers examined the impact of renal impairment, as measured by estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD) stages, on the mid-term survival in patients undergoing transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR). They included data from 29,893 patients enrolled in the German Aortic Valve registry from January 2011 to December 2015 receiving TAVI (n = 12 834) or SAVR (n = 17 059) at 88 sites. Observations revealed independent value of CKD ≥ 3b and CKD ≥ 3a as major risk factors for mortality in patients undergoing TAVI and SAVR, respectively. In the overall population of patients with severe aortic stenosis, a better selection of patients suitable for such therapies may be aided by an appropriate stratification based on CKD substage.