CVS Practice Test

There are three bipolar limb leads in an electrocardiogram (ECG). These leads are created by measuring the electrical potential difference between pairs of electrodes placed on the limbs. Specifically, the three bipolar limb leads correspond to the following pairs: lead I (right arm to left arm), lead II (right arm to left leg), and lead III (left arm to left leg). Understanding that these leads evaluate the heart's electrical activity from different angles helps in diagnosing various heart conditions. The configuration of these leads is essential in providing a more comprehensive view of the heart’s electrical activity by creating a triangular formation known as Einthoven's triangle. In contrast, the other answer choices reflect a misunderstanding of the standard ECG lead configuration. There are not two, four, or five bipolar limb leads as commonly recognized in standard clinical practice, reinforcing the significance of knowing that there are specifically three bipolar limb leads.