Percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) achieves high patency rates. Conversely, it has been shown that after thrombolysis, early reocclusion of the infarct-related artery (IRA) is associated with substantial morbidity and mortality. The aim of this retrospective study was to study the incidence, prognostic implications, and clinical risk factors for in-hospital reocclusion of the IRA after successful emergency PTCA for AMI. We studied 399 consecutive patients (aged 59+/-14 years, 52% with anterior wall infarction) admitted <6 hours after AMI onset, of whom 374 (94%) were successfully treated with primary (n = 297) or rescue (n = 77) PTCA, with a stenting rate of 8%. Predischarge angiography was performed in 306 (82%). Early reocclusion of the IRA occurred in 28 patients (9%) and was silent in 6 (2%). The reocclusion rate was 10% for primary PTCA and 8% for rescue PTCA (p = NS). Twenty-two of 28 patients (6%) underwent repeat emergency coronary angiography because of early recurrent ischemia and most (n = 18) were treated with emergency PTCA. Early recurrent ischemia occurred mostly (86%) within 5 days of AMI onset. There was a higher prevalence of on-site hemorrhage (18% vs 5%, p = 0.007), blood transfusion (11% vs 2%, p = 0.01), pulmonary edema (21% vs 4%, p <0.01), and in-hospital death (21% vs 1%, p = 0.0001) in patients with predischarge reocclusion. On multivariate analysis, cardiogenic shock on admission and absence of dyslipidemia were strong and independent predictors (p = 0.01) of IRA reocclusion. In conclusion, early reocclusion after emergency PTCA occurred in 9% of the patients and was associated with substantial morbidity and mortality. This warrants attempts to decrease its incidence, e.g., with more frequent use of stents.