Unipolar leads are another name for which category of ECG leads?

• A. Standard limb leads
• B. Bipolar leads
• C. Augmented leads
• D. Unipolar leads

Answer: (C)

Unipolar means a lead measures the electrical potential from a single electrode against a common reference. In practice, the leads that use one limb electrode with this reference and are specifically taught as a distinct, amplified group are the augmented limb leads (aVR, aVL, aVF). They’re called augmented because their signals are amplified to fit the ECG tracing, making the single-electrode measurement more readable. Standard limb leads, by contrast, compare two electrodes (bipolar), so they aren’t unipolar. The chest (precordial) leads are also unipolar, but they’re typically described as unipolar chest leads rather than the augmented limb category. So the best match for unipolar leads among the options is augmented leads.