ABSTRACT: Thiele H, Zeymer U, Neumann FJ, Ferenc M, Olbrich HG, Hausleiter J, Richardt G, Hennersdorf M, Empen K, Fuernau G, Desch S, Eitel I, Hambrecht R, Fuhrmann J, Böhm M, Ebelt H, Schneider S, Schuler G, Werdan K; IABP-SHOCK II Trial Investigators: Intraaortic balloon support for myocardial infarction with cardiogenic shock. N Engl J Med 2012, 367:1287-1296.In the current international guidelines, intra-aortic balloon pump (IABP) counterpulsation is considered a class I treatment for acute myocardial infarction complicated by cardiogenic shock. However, evidence is based mainly on registry data, and there is a paucity of randomized clinical trials.To test the hypothesis that IABP counterpulsation, as compared with the best available medical therapy alone, results in a reduction in mortality among patients with acute myocardial infarction complicated by cardiogenic shock for whom early revascularization is planned.Randomized, prospective, open-label, multicenter trial.Thirty-seven centers in Germany.All adults had acute myocardial infarction complicated by cardiogenic shock and were expected to undergo early revascularization (by means of percutaneous coronary intervention or bypass surgery).After enrollment, 600 patients were randomly assigned to intra-aortic balloon counterpulsation (IABP group, 301 patients) or no IABP counterpulsation (control group, 299 patients).The primary efficacy endpoint is 30-day all-cause mortality.At 30 days, 119 patients in the IABP group (39.7%) and 123 patients in the control group (41.3%) had died (relative risk with IABP, 0.96; 95% confidence interval, 0.79 to 1.17; P=0.69). There were no significant differences in secondary endpoints or in process-of-care measures, including the time to hemodynamic stabilization, the length of stay in the intensive care unit, serum lactate levels, the dose and duration of catecholamine therapy, and renal function.The use of IABP counterpulsation did not significantly reduce 30-day mortality in patients with acute myocardial infarction complicated by cardiogenic shock for whom an early revascularization strategy was planned.