Different leads used in electrocardiography (Column X) and the electrode placement and connections (Column Y) are listed below:

Which one of the following options represents the correct match between Column X and Column Y?

Correct option is D

Explanation:

• Standard limb lead I (a) records the potential difference between the left arm (positive) and the right arm (negative), so the correct match for a is iv.

• Standard limb lead II (b) records the potential difference between the left leg (positive) and the right arm (negative), so the correct match for b is i.

• Standard limb lead III (c) records the potential difference between the left leg (positive) and left arm (negative), so the correct match for c is ii.

• Augmented limb lead aVR (d) uses the right arm (positive) and the left arm and left leg connected together (negative) to record the potential difference, so the correct match for d is iii.

Thus, the correct matching is:
a-iv, b-i, c-ii, d-iii.

Information Booster:

1. ECG leads are crucial in evaluating the heart's electrical activity, which aids in diagnosing heart conditions.

2. The standard limb leads (I, II, III) measure the electrical potentials between the limbs in different combinations.

3. Augmented limb leads (aVR, aVL, aVF) measure the electrical activity using a single positive electrode and a combination of other electrodes as negative references.

4. Proper electrode placement ensures accurate results for both diagnosis and monitoring of heart function.