Red blood cell distribution width in patients undergoing transcatheter aortic valve implantation: Implications for outcomes

Background Red cell distribution width (RDW) is recently emerging as a prognostic indicator in many cardiovascular diseases. However, less is known about its predictive role in patients undergoing transcatheter aortic valve implantation (TAVI). Methods We retrospectively included very high‐risk patients with severe aortic valve stenosis undergoing TAVI between February 2012 and December 2019. Patients were classified according to RDW tertiles. Our primary endpoint was long‐term all‐cause mortality. The secondary endpoint was a composite of in‐hospital major adverse events as defined by the Valve Academic Research Consortium 2 criteria and/or long‐term all‐cause mortality. Results A total of 424 patients [median age 83.5 years, 52.6% females] were analysed. After a median follow‐up of 1.55 years, all‐cause mortality was 25.5%. At the multivariate‐adjusted Cox regression analysis, patients in the highest RDW tertile were associated with a higher risk for all‐cause mortality [hazard ratio [HR] 1.73, 95%confidence interval [CI] 1.02‐2.95] compared with the lowest tertile. When considering RDW as a continuous variable, we found an 11% increased risk in overall mortality [HR 1.11, 95% CI 1.00‐1.24] for each increased point in RDW. The highest RDW tertile was also independently associated with the occurrence of the composite endpoint [odds ratio [OR] 2.10, 95% CI 1.17‐3.76] compared with lower tertiles. Conclusions In our cohort, elevated basal RDW values were independent predictors of increased long‐term mortality and higher rate of in‐hospital adverse events. The inclusion of a routinely available biomarker as RDW, may help the pre‐operative risk assessment in potential TAVI candidates and optimise their management.