THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The electrical signals for the unipolar leads are “augmented” by disconnecting the exploring electrode from the reference electrode. Since the reference electrode has zero potential, the augmented potential represents only that measured by the three electrodes.

Detailed explanation-2: -The augmented unipolar limb leads aVR, aVL, and aVF, introduced by Goldberger in 1942, are an integral part of the 12-lead ECG [1, 2]. Leads I, II, and III have 2 dedicated electrodes, but the other 9 leads have a single dedicated electrode, and another one constructed from the averaged inputs of multiple electrodes.

Detailed explanation-3: -The unipolar extremity leads are called avR, avL and avF, and the chest leads are called V1–V6.