Background: There is evidence that the addition of nonstandard electrocardiographic (ECG) leads results in significant increases in sensitivity for the diagnosis of acute myocardial infarction compared with the standard 12-lead ECG., Objective: To examine how cardiologists and emergency physicians in British Columbia use nonstandard ECG leads (V4R to V6R and V7 to V9) in the diagnosis and treatment of acute myocardial infarction., Design: A list of fax numbers of all cardiologists and emergency physicians in British Columbia was obtained and questionnaires were then transmitted., Main Results: More than 75% of cardiologists and emergency physicians correctly identified the diagnostic criteria for acute right ventricular and posterior myocardial infarction. More than 70% of surveyed physicians reported that they would use the 18-lead ECG regularly if they could gain an increased sensitivity for the diagnosis of acute myocardial infarction. However, fewer than 20% of all surveyed physicians reported regular use of the 18-lead ECG. Furthermore, the survey determined that the majority of physicians would alter their choice of thrombolytic if they could diagnose right ventricular infarction complicating an inferior infarction. Finally, most physicians reported that they would treat an isolated posterior wall myocardial infarction with a thrombolytic., Conclusions: This study suggests most cardiologists and emergency physicians in British Columbia are aware of 18-lead ECG diagnostic criteria for acute right ventricular and posterior wall myocardial infarction. Furthermore, these physicians would be willing to use this tool if it were to increase diagnostic sensitivity for acute myocardial infarction. Despite these findings, only the minority of surveyed physicians use this tool regularly.