The above-mentioned ECC results about on-pump, beating-heart CABG pay much attention to the biventricular assist (BiVA). Nonetheless, much evidence also reveals that BiVA triggers an intense inflammatory response due to extracorporeal membrane lung and circuit line. Comparatively speaking, single left ventricular assist (LVA), with shorter circuit line, less priming volume and free of extracorporeal membrane lung, theoretically should reduce the inflammatory response and relative complications. As a result, aiming to the high-risk patients with severe left ventricle dysfunction, who need ECC assistance (BiVA or LVA), the investigators designed the randomized prospective study to evaluate: 1) the differences in myocardial injury as expressed by cardiac Troponin I(cTnI) and in inflammatory response by C-reactive protein (CRP), 2) the differences in the early postoperative outcomes including graft number, incidence of atrial fibrillation, in-hospital mortality and ICU stay.