Red Cell Distribution Width as a Prognostic Marker in Patients Undergoing Valve Surgery.

ABSTRACT

BACKGROUND: Numerous studies have shown that elevated red cell distribution width (RDW) is associated with poor outcomes in patients with cardiovascular diseases such as acute myocardial infarction, stroke, and chronic heart failure. The prognostic utility of RDW in patients with valvular disease undergoing heart valve surgery is unknown. METHODS: A prospective study was conducted on a group of consecutive patients with hemodynamically significant valvular heart disease that underwent elective valvular surgery. The preoperative complete blood count, data on risk factors, course of operations and the postoperative period were assessed. The primary and secondary endpoints were 30-day mortality and any major adverse event within 30 days. The data were analyzed with Kaplan-Meier survival curves, regression analyses, and receiver operator characteristic (ROC) curves. RESULTS: The study group included 500 consecutive patients who underwent replacement or repair of the valve/valves. Sixteen patients died during the follow up period. On multivariate analysis, creatinine (p = 0.04), red blood cell (RBC) count (p = 0.005) and RDW (p = 0.02) were each associated with an increased risk of death. The composite endpoint occurred in 208 patients. On multivariate analysis, chronic kidney disease (p = 0.003), raised pulmonary blood pressure (p = 0.02) and RDW (p = 0.001) remained independent predictors of the secondary endpoint. The preoperative RDW in patients with valvular disease undergoing valve surgery, combined with EuroSCORE II, predicted 30-day mortality significantly better than did EuroSCORE II alone. CONCLUSIONS: An elevated RDW is associated with a worse outcome following valve surgery. The predictive ability of the RDW, when assessed by the area under the ROC curve, improved the predictive ability of the EuroSCORE II calculator.