Red Cell Distribution Width and Coronary Artery Bypass Surgery

OBJECTIVES:

The red cell distribution width (RDW) has been identified as an independent risk factor with regard to prognosis in patients with coronary artery disease with or without heart failure. We sought to investigate the role of RDW in patients undergoing isolated coronary artery bypass graft surgery (CABG).

METHODS:

Analysis of consecutive patients on a validated prospective cardiac surgery database was performed for patients undergoing isolated CABG. Univariate and multivariate analysis was performed for in hospital mortality, long-term survival, length of hospital stay, length of intensive care unit stay and creatinine kinase muscle-brain (CKMB) release.

RESULTS:

Overall mortality was 2.1% for all cases, N = 8615. Median follow up was 5.8 years. Univariate analysis demonstrated that the RDW has a significant effect on CKMB release, P = 0.001, in-hospital mortality, P < 0.0001, and long-term survival, P < 0.0001, but no significant effect on the ITU length of stay, P = 0.9, or hospital length of stay, P = 0.2. Multivariate analysis revealed that the RDW was a significant factor determining in-hospital mortality and long-term survival, but had no significant effect on CKMB release, ITU or hospital length of stay. Confounding factor analysis revealed that in the absence of anaemia, the RDW was still a significant factor determining in-hospital mortality and long-term survival.

CONCLUSIONS:

The RDW is a significant factor determining in-hospital mortality and long-term survival in patients undergoing isolated CABG. The mechanism of association requires further study.