What lead is associated with recording electrical activity from the right arm to the left leg?

• A. Lead I
• B. Lead II
• C. aVL
• D. aVF

Answer: (B)

Lead II is associated with recording electrical activity from the right arm to the left leg. This lead is one of the standard bipolar limb leads used in electrocardiography. In Lead II, the positive electrode is placed on the left leg, while the negative electrode is placed on the right arm, allowing for the detection of the heart’s electrical activity as it travels from the right side of the heart to the left side. This lead provides a good view of the heart's rhythm and is particularly useful for diagnosing various cardiac conditions.

The other leads provide different perspectives on the heart's electrical activity. For instance, Lead I records from the left arm to the right arm, while aVL and aVF are unipolar leads that measure the voltage with respect to a central point; aVL records from the left arm to a diagonal reference point, and aVF records from the left leg to a reference point. Each lead configuration yields unique information about the heart's activity from different angles, but Lead II specifically channels the electrical flow from the right arm to the left leg.