Ischemia Index to predict post coronary artery bypass graft change in left ventricular ejection fraction

Introduction: Both myocardial necrosis and ischemia can decrease the left ventricular ejection fraction (LVEF). An accurate estimate of the relative contributions of these irreversible and potentially reversible factors could lead to better decisions regarding the risk and benefit of coronary artery bypass grafting (CABG). The value of an Ischemia Index calculated by subtracting the ECG estimated infarction dependent LVEF from the measured LVEF to predict post-operative improvement of LVEF was studied in 55 patients with LVEF <40% before CABG. Patients were grouped according to absence or presence of other coexisting ECG confounders. Results: No significant (p=0.083) relationship was found between the Ischemia Index and the improvement in LVEF after CABG in the overall population, but a strong trend was present in the patients with ECGs without confounding QRS changes (p=0.056). Conclusion: These results suggest a positive relationship between the Ischemia Index and improvement of LVEF after CABG in patients without electrocardiographic confounders, but a prospective study using a larger sample is needed. (C) 2013 Elsevier Inc. All rights reserved.