Prof. Charles J. Ferro, Department of Nephrology, Queen Elizabeth Hospital, Birmingham B15 2WB, United Kingdom.
Objectives The study sought to determine the risk factors for post-transcatheter aortic valve replacement (TAVR) dialysis and to determine the impact of pre-TAVR or post-TAVR dialysis on mortality.
The prevalence of pre-procedural renal dysfunction in patients undergoing TAVR is high (50% to 60% with chronic kidney disease [CKD] stage 3 or worse) (3,4) and has been shown to be significantly associated with increased mortality (3,4) and acute kidney injury (AKI) (5) post-TAVR. However, although the reported new need for dialysis after TAVR has been examined in several studies (6–22), most are single center and report data on <300 patients with rates for post-procedure dialysis varying between 0% and 21%. A recent meta-analysis examining the impact of AKI after TAVR analyzed 13 studies and reported a rate of new dialysis of 5.8% (89 of 1528 patients) (5). A high (9-fold increase) mortality at 1 year associated with the need for dialysis after TAVR was reported in a single study of 270 subjects (16). Data from the German TAVI-registry also suggested new dialysis requirement after TAVR was associated with higher mortality at 30 days but not at 1 year (23). To the best of our knowledge no study has yet compared outcomes of patients requiring dialysis support after TAVR with those already on dialysis before the procedure.
The median follow-up period was 625 (268 to 1,208) days. Overall, 2,486 (37%) patients died during the follow-up period. In total, 314 (4.9%) patients died during the hospital admission. Two hundred twenty-three (3.7%) patients with no dialysis requirement, 9 (7.8%) patients on dialysis before the procedure, and 82 (40.6%) patients requiring dialysis after TAVR died in hospital (p < 0.001). The Kaplan-Meier cumulative survival curves are shown in Figure 2. The Kaplan-Meier mortality estimates in patients with no dialysis requirements were 0.06, 0.07, 0.08, 0.16, and 0.46 at 30 days, 60 days, 90 days, 1 year, and 4 years, respectively. These were significantly higher in patients requiring dialysis after the procedure at 0.35, 0.45, 0.50, 0.64, and 0.84 at the same time points (log-rank p < 0.001). Mortality was also higher in patients requiring dialysis after TAVR compared with those already on dialysis before the procedure (log-rank p < 0.001).
Dr. Doshi has served as a proctor for Edwards and Boston Scientific. Mr. Moat has served as a proctor and consultant to Medtronic. Dr. Hildick-Smith has served as a proctor and consultant for Boston Scientific, Medtronic, and Edwards. Dr. Townend has received educational support and training from Edwards. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(2015) Transcatheter aortic valve implantation in patients with pre-existing chronc kidney disease. IJC Heart Vasc 8:9–18.