Randomized, multicenter, Phase III, controlled clinical trial. Patients with shock due to left ventricular failure complicating myocardial infarction were randomly assigned to emergency revascularization or initial medical stabilization. Revascularization was accomplished by either coronary-artery bypass grafting or angioplasty. A total of 152 patients were randomized to early revascularization and 150 patients to conventional therapy consisting of thrombolytics and a possible late attempt at revascularization. Intraaortic balloon counterpulsation was performed in 86 percent of the patients in both groups. The primary endpoint was mortality from all causes at 30 days. Secondary endpoints included all-cause mortality at six months and assessment of the quality of life in survivors after discharge.