Certified EkG technician (CET) Practice Exam

Where should an EKG technician place the electrodes for leads V7, V8, and V9?

1. On the anterior chest

2. Evenly spaced on the back between the axillary line and the vertebral column

3. On the left arm

4. Centered on the abdomen

The correct answer is: Evenly spaced on the back between the axillary line and the vertebral column

For leads V7, V8, and V9, the electrodes are placed on the back, which is why the correct response emphasizes the positioning between the axillary line and the vertebral column. These leads are specifically used to gain additional views of the heart, particularly the left lateral wall, which is important in assessing certain cardiac conditions, such as those involving the left side of the heart. Placing the electrodes in this manner ensures that they are positioned accurately for optimal readings. They provide valuable information in conjunction with the standard 12-lead EKG setup. The space between the axillary line and the vertebral column is critical for ensuring that the readings reflect the electrical activity of the heart from the appropriate angles needed for an accurate analysis. In contrast, placing electrodes on the anterior chest, on the left arm, or centered on the abdomen would not provide the correct views needed for leads V7, V8, and V9. Such placements could result in misleading data, making it imperative that technicians understand the specific anatomical locations for each lead.