Impact of Pre-existing Kidney Dysfunction on Outcomes Following 
Transcatheter Aortic Valve Replacement

BACKGROUND: Pre-existing chronic kidney disease (CKD) portends adverse outcomes following heart valve surgery. However, only limited and conflicting evidence is available on the impact of CKD on outcomes following transcatheter aortic valve replacement (TAVR). The objective of this review was to evaluate the effect of pre-existing CKD on TAVR outcomes. METHODS: We performed a systematic electronic search using the PRISMA statement to identify all randomized controlled trials and observational studies investigating the effect of pre-existing CKD on outcomes following TAVR. 30-day and long-term outcomes were measured comparing patients with Glomerular filtration rate (GFR) ≥60 to those with GFR <60. RESULTS: Ten studies were analyzed comprising of 8688 patients. Compared to patients with GFR ≥60, those with GFR < 60 had worse 30-day all cause mortality (OR 1.40, 95% CI: 1.13-1.73), cardiovascular mortality (OR 1.66, 95% CI: 1.04-2.67), strokes (OR 1.39, 95% CI: 1.05-1.85), acute kidney injury (OR 1.42, 95% CI: 1.21-1.66) and the risk for dialysis (OR 2.13, 95% CI: 1.07-4.22). There was no difference in device success (p=0.873), major or life threatening bleeds (p = 0.302), major vascular complications (p=0.525), need for pacemaker implantation (p = 0.393) or paravalvular leaks (p = 0.630). All-cause mortality at 1 year was also significantly higher in patients with GFR <60 (OR 1.80, 95% CI: 1.26-2.56). CONCLUSION: Pre-existing CKD defined as GFR <60 is a strong predictor of worse short and long-term outcomes following TAVR. Active measures should be taken to mitigate the postprocedure risk in these group of patients.