Electrocardiographic Limb Leads Placement and Its Clinical Implication

INTRODUCTION Since its introduction, the electrocardiography (ECG) has become the most commonly performed cardiac diagnostic procedure and a fundamental tool of clinical practice.1,2 It is indispensable for the diagnosis and prompt treatment of patients with acute coronary syndromes and is an accurate, noninvasive tool for diagnosing cardiac conduction disturbances and arrhythmias. Proper, standard ECG leads placement is essential in providing accurate information from the recordings. Modified limb leads placement on the torso has the important advantages of ease and speed of application, particularly in emergent situations and has become commonplace. However, modified limb placement was reported to have unwanted abnormal ECG findings.3 Clinically significant abnormal ECG findings due to this modified, non-standard limb placement are illustrated by two cases.