Which leads are known as the limb leads in a 12-lead EKG?

The limb leads in a 12-lead EKG consist of Leads I, II, III, aVR, aVL, and aVF. These leads are directly derived from the electrodes placed on the limbs (the arms and legs) of the patient.

Leads I, II, and III are bipolar leads, meaning they measure the electrical potential difference between two electrodes. Lead aVR provides information from the right arm, aVL from the left arm, and aVF from the feet, representing augmented leads that offer perspectives on electrical activity in the heart from specific angles. Collectively, these leads are crucial for assessing the heart's electrical activity from a frontal plane viewpoint.

Other choices refer to different lead groups; for instance, Leads V1 to V6 are precordial leads placed on the chest that help visualize heart activity in the horizontal plane. The lettered options (A, B, C, D) do not represent valid EKG lead designations, adding to the clarity that A is indeed the correct choice. Thus, understanding the role of limb leads is essential for diagnosing various cardiac conditions effectively.