Coronary artery bypass grafting in patients with low ejection fraction: The effect of intra-aortic balloon pump insertion on early outcome

Background: Survival benefit with intra-aortic balloon pump (IABP) insertion for coronary artery bypass grafting (CABG) patients with left ventricular dysfunction is controversial. The aim of this study was to assess the early results of CABG that predict 30-day mortality and prolonged length of hospital stay (LOS) after isolated CABG and the role of IABP application as a main predictor in patients with an ejection fraction (EF) of 30% or less.
Materials and Methods: Eight hundred and thirty-three patients who underwent isolated CABG with EF ≤ 30% were entered and compared with 10881 patients with EF > 30% as the control group. Demographic and clinical characteristics and postoperative complications were considered. Data were analyzed using the student′s t-test and chi-square test for univariate analysis and the analysis of covariance and logistic regression for multivariate analysis.
Results: The thirty-day mortality rate (1.6% vs. 0.7%, P < 0.001), the mean of LOS (P < 0.001), and the mean of the length of ICU stay (P < 0.001) were significantly higher in the severe left ventricular dysfunction group than in the control group. In patients with severe left ventricular dysfunction, the use of intra-aortic balloon pomp was related to the 30-day mortality rate (P = 0.002) and prolonged LOS (P = 0.009). Also, urinary tract infection, prolonged ventilation, and renal failure as postoperative complications were statistically more in the group with the application of IABP.
Conclusion: Low ejection fraction can positively affect thirty-day mortality and prolonged LOS and ICU stay in patients who undergo CABG. In these patients, IABP insertion is a strong predictor for early complication and mortality.

Keywords
Coronary artery bypass grafting, intra-aortic balloon pump, left ventricular dysfunction, outcome