Abstract: In order to evaluate the accuracy of left ventricular ejection fraction(EF)and fractional shortening(FS)for predicting malignant ventricular arrhythmia(VA)after coronary artery bypass graft(CABG). One hundred and fifty consecutive patients were selected for an isolated CABG procedure, EF and FS, left ventricular potential(LVP), myocardial enzymes and 24 h Holter were measured in special perioperative period. 1)Patients with previous myocardial infarction(MI), aneurysm, positive LVP had obviously lower value of EF and FS before CABG than those without them. 2)In patients with LVD, significant improvements were found in EF and FS indexes after CABG. 3)The incidence of postoperative VA is higher in these patients with LVD, VA, VLP+ and aneurysm than the others. The results showed that: 1)EF and FS were sensitive indexes in reflecting left ventricular function. 2)CABG and aneurysmectomy not only improved myocardial blood supply, but also increased the heart out put, and brought the best benefits to those patients with LVD. 3)For the reason of myocardial depression, the cardiac function of patients without LVD decreased in short term follow up(14±1)d. 4)EF≤40% and/or EF≤24% were independent predictors for the prevision of malignant VA, the value of FS accurately reflected left ventricular function. 5)Integrate with other indexes, such as LVD, VLP and aneurysm, would improve the sensitivity, specialty and accuracy for predicting malignant VA after CABG.

Key words: left ventricular ejection(EF)|fractional shortening(FS)|coronary artery bypass grafting(CABG)|ventricular arrhythmia