These leads have one positive and one negative electrode, making them what type of leads?

These leads have one positive and one negative electrode, making them what type of leads?

• A. Bipolar leads
• B. Unipolar leads
• C. Central terminal leads
• D. Standard limb leads

Answer: (A)

Having one positive and one negative electrode defines a bipolar lead. A lead records the electrical potential difference between two distinct body sites, and the polarity is set by which electrode is positive and which is negative. This is exactly what the classic standard limb leads do: they pair two limb electrodes to form a single lead, giving you a measurement of the heart’s activity along that axis. In contrast, unipolar leads use one active electrode against a distant reference (often a Wilson central terminal), and central terminal leads are specific unipolar configurations. So, when a lead consists of two electrodes with opposite poles, it’s a bipolar lead.