Emergency percutaneous transluminal coronary angioplasty was performed in 62 patients with acute myocardial infarction complicated by hypotension. All patients were treated within 12 hours of the onset of chest pain. Angioplasty was completely successful (residual lesion less than or equal to 50%) in 48 patients, partially successful (patent vessel greater than 50% residual lesion) in four patients, and unsuccessful in 10 patients. Patients in whom angioplasty was successful had a hospital mortality rate of 19%; those in whom angioplasty was unsuccessful or only partially successful had hospital mortality rates of 60% and 50%, respectively, (p = 0.012). Patients with occlusion of the proximal left anterior descending vessel had the highest failure rate (42%) and the highest mortality rate (67%). Other univariate predictors of hospital mortality were older age and elevated end-diastolic pressure. Successful emergency angioplasty improves mortality in patients with acute infarction complicated by hypotension.