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

Abstract

Objectives: 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).

Methods: 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 ≤15.5%, 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.

Results: Compared with the patients with RDW ≤15.5% (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].

Conclusions: 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.

Keywords: Aortic valve stenosis; Elderly; Red cell distribution width; Transcatheter aortic valve implantation.