Acute cardiogenic shock or cardiac arrest (CS/CA) before cardiopulmonary bypass (CPB) installation are life-threatening events in acute coronary syndromes. We evaluated whether continuous retrograde warm-blood perfusion(CRWBP) before aortic cross-clamping (ACC),with immediate CPB installation may improve hospital results in these dreadful events. Hospital outcome of 18 coronary artery bypass grafting (CABG) (Group A) with CS/CA before CPB, with immediate CPB installation and CRWBP,has been compared with 24 CABG (Group B) with CS/CA undergoing only immediate CPB installation. No differences have been detected in the mean time to establish CPB(P = 0.655). Electrocardiography normalized in a significantly higher number of CRWBP (P = 0.0001). Group B showed longer CPB (116.2 +/- 21.2 min vs. 157.8 +/- 32.4;P = 0.0001) and postoperative intra-aortic balloon pumping time course (36.2 +/- 5.9 h vs. 77.8 +/-13.2; P = 0.0001).CRWBP reduced postoperative acute myocardial infarction (P = 0.004) and damage (P = 0.033), death (P = 0.026),and need for high inotropic support (0% vs. 37.5%; P =0.003). Troponin I was significantly lower in Group A(P = 0.013 from coronary sinus; P </= 0.0001 at 12, 24, and 48 h postoperatively; P = 0.008 at 72 h), never reaching values suggestive of acute myocardial infarction. Group A had also lower lactate release from aortic declamping to 48 h postoperatively (P </= 0.0001).CRWBP improved post operative left ventricular ejection fraction (EF) (P = 0.017)and wall motion score index (P = 0.041), whereas Group B showed a significant worsening of EF (P = 0.0001) and wall motion score index (P = 0.002). Patients in Group A had shorter intubation time (P = 0.0001), intensive therapy unit(ITU) stay (P = 0.001), and hospital stay (P = 0.0001).CRWBP reverses myocardial damage in patients with CS/CA during acute coronary syndromes, adding a straightforward benefit to hospital survival.