(Case 3) Acute, isolated posterior wall myocardial infarction. (Case 3) Acute, isolated posterior wall myocardial infarction. (A) The ECG demonstrated pronounced ST segment depression in leads V1 to V3 with prominent R waves; these findings are consistent with posterior wall AMI versus anterior wall ischaemia. (B) Posterior electrocardiographic leads V8 and V9 revealed ST segment elevation, confirming the diagnosis of acute, isolated posterior wall myocardial infarction. T Pollehn et al. Emerg Med J 2002;19:129-135 Copyright © BMJ Publishing Group Ltd and the College of Emergency Medicine. All rights reserved.