Red cell distribution width improves the prediction of prognosis after transcatheter aortic valve implantation

The aim of this study was to determine if red cell distribution width (RDW) could improve the prediction of prognosis after transcatheter aortic valve implantation (TAVI). In this single-centre study, 197 consecutive patients underwent TAVI (median age 82 (77-86), 46.2% men). Normal RDW at baseline was defined as a parts per thousand currency sign15.5%, elevated RDW at baseline was defined as > 15.5%. Ouctomes according to the Valve Academic Research Consortium 2 and survival up to one year were compared between these groups. Compared with the patients with RDW a parts per thousand currency sign15.5% (n = 168), those with RDW > 15.5% (n = 29) had a higher Society of Thoracic Surgeon (STS) score (7.2 vs 5.0%, P = 0.041), higher systolic pulmonary arterial pressure (50 vs 41 mmHg, P = 0.021) and lower haemoglobin (11.5 vs 12.4 mg/dl, P = 0.003). Patients with RDW > 15.5% developed significantly more adverse events after TAVI (major vascular complications: 10.3 vs 1.8%, P = 0.042; aortic regurgitation grade II-IV: 50.0 vs 18.0%, P = 0.001) and survival up to 1 year was significantly lower (85.6 vs 65.2%, log-rank: P = 0.007). In addition, RDW > 15.5% at baseline was the most significant predictor for mortality (hazard ratio: 2.701 (1.279-5.704), P = 0.009), even when the STS score was added to the model [RDW > 15.5%: hazard ratio: 2.276 (1.045-4.954), P = 0.038]. Elevated RDW is a significant predictor for adverse events and increased 1-year mortality after TAVI. Adding RDW to the classical STS score could be a valuable strategy to improve preoperative risk assessment in potential TAVI candidates.