Is severely left ventricular dysfunction a predictor of early outcomes in patients with coronary artery bypass graft?

Background: Traditionally, the Coronary artery bypass grafting (CABG) surgery outcomes of patients with low ejection fraction (EF) have been worse compared to patients with moderate to good left ventricular function. During the past decade, despite improvements in surgical techniques, the trend in the outcomes of these patients remained unclear.

Aim: We sought to determine the effect of left ventricular dysfunction on early mortality and morbidity and to specify predictors of early mortality of isolated CABG in a large group of patients EF≤35%.

Method: We retrospectively analyzed data of 14 819 consecutive patients undergoing isolated CABG from February 2002 to March 2008 at Tehran Heart Center. Patients were divided into two groups based on their LVEF (EF≤35% and EF>35%). Differences in case-mix between patients with EF≤35% and those without were controlled by constructing a propensity score.

Results: Mean age of our patients was 58.7±9.5 years. EF≤35% was present in 1342 (9.1%) of patients. In-hospital mortality was significantly increased univariate in EF≤35%, while this association diminished after confounders were adjusted for by using the propensity score (p=0.242). Following adjustment it was demonstrated that renal failure, cardiac arrest, heart block, infectious complication, total ventilation time, and total ICU hours were more frequent in patients with EF≤35%.

Conclusion: We demonstrated EF≤35% was not predictor of in-hospital mortality in patients underwent CABG. Careful preoperative patient selection remains essential in patients with EF≤35% undergoing CABG.