In a standard Electrocardiogram, an augmented limb lead measures the electrical potential difference between

Augmented limb leads are recordings between one limb and the other two limbs Augmented limb leads, designated by the letter a (aVR, aVL, aVF), are generally used Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:495 aVR: b/w right arm (+electrode)and left arm+left leg(-electrode) aVL: b/w the left arm(+electrodes) and right arm+left leg(-electrode) aVF: b/w the left foot (+electrode)and right arm+left arm(-electrode) Vector of augmented limb lead=3/2 vector of unaugmented limb lead.