Progressive rise in red cell distribution width is associated with poor outcome after transcatheter aortic valve implantation.

Objective: To investigate the prognostic value of baseline and temporal changes in red cell distribution width (RDW) in patients undergoing transcatheter aortic valve implantation (TAVI).

Design: Single-centre retrospective observational study.

Setting: Tertiary cardiac centre.

Patients: 175 patients undergoing TAVI were included in this study.

Main Outcome Measure: Survival.

Results: We analysed data from 175 TAVI patients (mean (± SD) age 83 ± 7 years, 49% men, mean Logistic EuroSCORE 23 ± 1, 66% preserved left ventricular ejection fraction (LVEF)). Immediately pre-TAVI, mean RDW was 14.6 ± 1.6% with an RDW>15% in 29% of patients. Over median follow-up of 12 months, the median rate of change in RDW was 0.2% per month, and 51 (29%) patients died. On multivariate survival analyses, baseline RDW ≥ 15.5% predicted death (adjusted HR 2.70, 95% CI 1.40 to 5.22, p=0.003) independently of LVEF, transfemoral approach, baseline pulmonary artery systolic pressure, moderate/severe mitral regurgitation and body mass index. A greater rate of increase in RDW over time was associated with increased mortality (adjusted HR 1.11, 95% CI 1.04 to 1.18, p=0.001) independently of baseline RDW and other significant temporal variables including a change in creatinine, bilirubin, mean cell haemoglobin concentration or urea. An increase in RDW>0.1%/month was associated with a twofold increased risk of mortality.

Conclusions: Baseline RDW ≥ 15.5% and a rising RDW over time strongly correlate to an increased risk of death post-TAVI, and could be used to refine risk stratification. Investigating and ameliorating the causes of RDW expansion may improve survival.