Can red blood cell distribution width predict long-term cardiovascular event after off-pump coronary artery bypass? A retrospective study.

ABSTRACT

INTRODUCTION: The effect of red blood cell distribution width (RDW) on long-term major cardiac and cardiovascular event (MACCE) in patients with off-pump coronary artery bypass (OPCAB) has not been adequately studied. We investigated the relationship between RDW and the risk of MACCE in patients who underwent OPCAB. METHODS: We retrospectively analyzed the data of 440 consecutive, nonanemic patients (362 males; 82.27% and mean age 60.8 ± 8.9 years) who underwent OPCAB between October 2009 and September 2012 in Fuwai Hospital. Long-term follow-up was obtained through phone calls, hospital records, and clinic visits. MACCE (death, ST elevated infarction, repeat coronary revascularization, stroke) was determined. RESULTS: Over a median of 7.0-year follow-up, 80 incident MACCE events were identified. The RDW levels on admission were significantly higher in MACCE group than non-MACCE group (13.1 ± 0.7 vs 12.8 ± 0.7; P = .005). Using the Cox proportional hazards models, we found that per 1% increment of RDW, the incident of MACCE was increased in different models (hazard ratio [HR] was 1.520, 1.532, and 1.795, respectively; P = .002, .004, and .002). The receiver-operating characteristic analysis revealed an RDW cut-off value of 13% predicting MACCE. Therefore, patients were grouped on this cut-off value. The Kaplan-Meier plot revealed significantly lower event-free survival in the higher RDW group (P = .0158). Compared with subjects in the RDW <13% in full model, subjects in the RDW ≥13% had an HR of 1.829 (95% confidence interval, 1.103-3.032; P = .019). CONCLUSIONS: An RDW level greater than 13% in hospital admission is independently associated with an increased incidence of long-term MACCE after OPCAB.