Lead V4 is located at which intercostal space and which chest line?

Lead V4 is located at which intercostal space and which chest line?

• A. 3rd intercostal space; right midclavicular line
• B. 5th intercostal space; left midclavicular line
• C. 4th intercostal space; left anterior axillary line
• D. 6th intercostal space; left midaxillary line

Answer: (B)

The main idea here is where chest leads for an ECG are placed to view the heart from different angles, with V4 specifically targeting the apex region. Lead V4 is placed in the left midclavicular line at the 5th intercostal space. This spot sits over the apex of the left ventricle, so placing the electrode there gives a strong, representative signal from the LV’s anterior-apical area. The left midclavicular line runs down from the midpoint of the clavicle, and the 5th intercostal space is the space between the fifth and sixth ribs. Other locations would not align with the heart’s apex or would view different regions, which is why they aren’t used for V4.

The main idea here is where chest leads for an ECG are placed to view the heart from different angles, with V4 specifically targeting the apex region. Lead V4 is placed in the left midclavicular line at the 5th intercostal space. This spot sits over the apex of the left ventricle, so placing the electrode there gives a strong, representative signal from the LV’s anterior-apical area. The left midclavicular line runs down from the midpoint of the clavicle, and the 5th intercostal space is the space between the fifth and sixth ribs. Other locations would not align with the heart’s apex or would view different regions, which is why they aren’t used for V4.