Characteristics of electrocardiographic repolarization in acute myocardial infarction complicated by ventricular fibrillation

Background and Purpose: Some de- and re-polarization patterns can reflect an increased risk of ventricular tachyarrhythmias. We studied whether some electrocardiographic (ECG) patterns are able to predict the development of ventricular fibrillation (VF) during acute myocardial infarction (MI). Methods: We compared the patterns of ST-T segment of 78 patients who developed VF during acute MI (patient with VF) vs 170 comparable patients with acute MI but with no VF complications. Results: Of the VF group, 47 developed out-of-hospital VF and 31 developed VF after their admission to the hospital. A steep downsloping ST segment toward a negative T wave with or without a short, flat, or rising portion at the initial portion was observed in 69.2% of the 78 patients: 61.3% in patients with pre-VF and 74.5% in patients with post-VF, vs 9.4% of patients who did not develop VF (P < .0001). In 90.6% of the latter, a typical upward-concave or convex "ischemic" pattern of the ST segment was observed. Thus, the characteristic ST-T patterns were highly associated with VF with a specificity greater than 90%. Conclusions: A steep downsloping ST segment may characterize the ECGs of patients who develop VF during acute MI. (c) 2012 Elsevier Inc. All rights reserved.