Cleveland Family Study

8.5.2 Chest Electrode Leads

8.5.2.1 Locating Electrodes V1 and V2

1. Standing on the left side of the participant, locate the sternal angle (where the manubrium joins the sternum) firmly in between the index and middle fingers of your right hand at the mid-sternal line.
2. Move your fingers along the sternal angle laterally to the right sternal border. This is where the second rib joins the sternum.
3. Locate the second rib firmly in between your two fingers. You now have your index finger in the second intercostal space at the right sternal border.
4. Replace your index finger position by your middle finger.
5. Move your index finger to the third intercostal space. Make sure that you feel the third rib in between your two fingers.
6. Replace the position of your index finger by your middle finger.
7. Move your index finger to the fourth intercostal space at the right sternal border.
8. Your index finger is now at the location of V1.
9. Make an X with your pen.
10. Now locate V2 at the level of V1 at the left sternal border.
11. Feel the fourth intercostal space and firmly mark the V2 location with your pen.
12. At this point, mark a dot in the midsternal line in between V1 and V2. This mark will serve as a reference level for V1 and V2 and the fourth intercostal space in case you lose the location marks of V1 and V2 during skin preparation.

8.5.2.2 Locating Horizontal Reference Level for Electrodes V4,V5, and V6 (Point E)

1. Starting from the V2 location, keep the middle finger of your right hand firmly in the fourth intercostal space.
2. Move it laterally and slightly diagonally downwards in the fourth intercostal space towards the nipple.
3. Feel the fifth rib with your index finger.
4. Move your middle finger to the fifth intercostal space.
5. Move your finger in the fifth intercostal space laterally to where the left midclavicular line intersects the fifth intercostal space. (The midclavicular line starts where you feel a bend in the clavicle. The midclavicular line is a longitude that runs from the bend in the clavicle downwards in the center of the thorax.)
6. Mark the exact transverse (horizontal) level of the point of intersection of the midclavicular line with the fifth intercostal space at the midsternal line below V1 and V2. It comes close to about one inch below the dot in between V1 and V2. This is your reference level E for the locations of V4, V5 and V6.

8.5.2.3 Locating Electrode V6

1. Move the participant’s elbow laterally away from his/her body.
2. Note the starting point of the left midaxillary line between the axillary folds formed by the anterior and posterior axillary lines.
3. Follow the midaxillary line in the exact vertical center plane of the thorax down to the intersection of the horizontal plane marked by the location of E.
4. This is the exact location of the V6 electrode. NOTE: It is a common mistake to locate the midaxillary line too far anteriorly, towards V5 location.

8.5.2.4 Locating Electrodes V3, V4, and V5

1. Place to mark the location of V4, which is at the intersection of the midclavicular line and the fifth intercostal space
2. Proceed to mark location V3, which is equidistant between V4 and V6