Raised red cell distribution width as a prognostic marker in aortic valve replacement surgery

Abstract

Background and aim: Several studies have reported that elevated red cell distribution width (RDW) is associated with poor outcomes in patients with coronary artery disease, chronic heart failure and aortic stenosis following transcatheter aortic valve replacement. Their prognostic utility in patients undergoing aortic valve replacement (AVR) surgery is unknown.

Methods: We prospectively evaluated the prognostic value of RDW in a group of 191 consecutive patients with severe symptomatic aortic stenosis undergoing AVR. The pre-defined primary endpoint at the 30-day follow-up was composed of: all cause mortality, perioperative myocardial infarction, perioperative renal failure, prolonged mechanical ventilation, stroke, heart failure, successfully resuscitated cardiac arrest, the occurrence of multiple-organ failure, and the need for additional surgery for any reason. The secondary endpoint was total mortality.

Results: The composite endpoint occurred in 54 patients. In univariate analysis RDW (p < 0.0001), haemoglobin level (p = 0.005), haematocrit (p = 0.01), red blood cell count (RBC; p = 0.002), glomerular filtration rate (p = 0.003), New York Heart Association classification (p = 0.02), atrial fibrillation (p = 0.0044), and pulmonary blood pressure (p = 0.004) were associated with the occurrence of the composite endpoint. RDW (p = 0.0005), haemoglobin level (p = 0.004), haematocrit (p = 0.004), RBC (p = 0.0009) and mean corpuscular volume (p = 0.01) were associated with an increased risk of death. In multivariate analysis, RDW (OR 3.274; 95% CI 1.285–8.344; p = 0.0003) and RBC (OR 0.373; 95% CI 0.176–0.787; p = 0.0097) remained independent predictors of the composite endpoint. Receiver operating characteristic analysis determined a cut-off value of RDW for the prediction of the occurrence of the combined endpoint at 14.1%.

Conclusions: Elevated RDW is associated with a worse outcome following AVR, independent of RBC.