Reinfarction is one of the major determinants of car- diac mortality after acute myocardial infarction. 1-7 Early identification of patients at high risk for reinfarction is important, especially nowadays, when there is a trend toward early discharge of patients with acute myocar- dial infarction. Patients prone to reinfarction may bene- fit from prolonged anticoagulant therapy, angiotensin- converting enzyme inhibitor therapy, 1 primary angioplasty (associated with lower rate of recurrent ischemia or reinfarction than thrombolysis 8-10 ), or early revascularization procedures. These patients may not be candidates for early discharge and may be sched- uled for longer stay in the intensive coronary care unit. However, clinical data, early stress testing including radionuclide scanning, and even coronary angiography have not proven useful in predicting either reinfarction or early reocclusion of the infarct-related artery. 5,8,11-16 Most previous studies have focused on predictors of reinfarction after hospital discharge and have not addressed early hospital reinfarction. 1-7,11 Moreover, no previous studies have included electrocardiographic variables in the predictive model for reinfarction except for the Q wave versus the non-Q-wave infarc- tion. This retrospective analysis assessed the prognostic significance of simple clinical and electrocardiographic variables routinely obtained at admission to predict reinfarction during the index hospitalization in patients with acute myocardial infarction treated with throm- bolytic therapy. Methods Patients The study population consisted of 2602 patients who were enrolled in the GUSTO-I trial in 25 medical centers in Israel from September 1991 through February 1993. All patients were admitted within 6 hours of onset of symptoms, had chest pain lasting at least 20 minutes and ≥0.1 mV of ST-seg- ment elevation in two or more consecutive limb leads, or ≥0.2 mV in two or more consecutive precordial leads. In this study we included only patients admitted in the hyperacute electro- cardiographic stage of infarction: ST-segment elevation accompa- Admission clinical and electrocardiographic characteristics predicting an increased risk for early reinfarction after thrombolytic therapy Yochai Birnbaum, MD, a Izhak Herz, MD, a Samuel Sclarovsky, MD, a Bruria Zlotikamien, MD, a Angela Chetrit, MSc, b Liraz Olmer, BSc, b and Gabriel I. Barbash, MD, MPH c Petah-Tiqva, Tel-Hashomer, and Tel Aviv, Israel Background This study assessed the ability of clinical and electrocardiographic variables routinely obtained on admission to identify patients with acute myocardial infarction treated with thrombolytic therapy at risk of early reinfarction. Methods and Results The study included 2602 patients who received thrombolytic therapy for acute myocardial infarction. Baseline demographic variables and admission clinical and electrocardiographic variables were compared between patients with and without reinfarction. Multivariable logistic regression technique was used and included recurrent infarction as the dependent variable, and baseline demographic, clinical, and electrocardiographic variables as indepen- dent variables. History of hypertension (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.00 to 2.31) and diabetes mel- litus (OR 1.59, 95% CI 1.00 to 2.53) were associated with a higher risk, and current smoking was associated with a lower risk (OR [no versus yes] 1.64, 95% CI 1.05 to 2.58) of early hospital reinfarction. Distortion of the terminal portion of the QRS complex (OR 1.86, 95% CI 1.20 to 2.87) and absence of abnormal Q waves on admission (OR 1.54, 95% CI 0.98 to 2.43) were associated with increased risk of early reinfarction. Conclusions A simple electrocardiographic sign is a reliable predictor of early reinfarction among patients who receive thrombolytic therapy for acute myocardial infarction. (Am Heart J 1998;135:805-12.) From a Beilinson Medical Center, b Sheba Medical Center, and c Tel Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University. Submitted Jan. 31, 1997; accepted Oct. 3, 1997. Reprint requests: Gabriel I. Barbash, MD, MPH, Tel Aviv Sourasky Medical Center, 6 Weizman St., Tel Aviv 64239, Israel. Copyright © 1998 by Mosby, Inc. 0002-8703/98/$5.00 + 0 4/1/88733