How to Perform an EKG Test

By Martha Adams; Updated April 25, 2017
An EKG is an important heart test.

A resting 12-lead EKG is an important diagnostic test that shows heart activity at rest. It is noninvasive and completely painless. It does not require the patient to perform any activity. It may also take place as part of an exercise or chemical stress test to increase heart activity and look for problems. Correct lead placement plays a vital role in obtaining accurate results.

Ask the patient to undress to the waist with pants legs rolled up and hosiery removed. The patient may wear a gown if desired.

Ask the patient to lie on her back. Expose the chest in sections as you apply the electrodes.

Apply the right and left arm electrodes anywhere on the arms between the shoulder and the wrist. Make sure they stay away from any bony prominences. Clean the skin and apply contact gel if necessary as you apply each electrode.

Apply the leg electrodes in the same way.

Locate the patient's right clavicle, place two fingers just below it and above the top rib. Count downward too the fourth intercostal space and place an electrode here. This is Lead V1.

Go to the left side of the chest, find the same spot and place an electrode. This is Lead V2.

Stay on the left side and count down one more intercostal space, move to the midclavicular line and place an electrode. This is Lead V4.

Draw a mental line between V2 and V4. Find a spot on that line that is not directly over a rib and place an electrode there. This is V3. (Yes, you place V3 after you place V4.)

Have the patient raise the left arm, find the center of the armpit and draw a mental line downward to the level of V4. Place an electrode here for V6.

Draw a mental line between V4 and V6 and place an electrode between them on this line, but not directly over a rib. This is V5. (You place V6 before V5.)

Connect each of the electrodes to the correct wire from the EKG machine.

Run the EKG, save the results to a computer or fold the paper strip.

Disconnect the wires, remove the electrodes, and clean the skin of any remaining gel or adhesive. Prepare the results for the doctor to read and interpret.

Tip

You may need to shave hair from a man's chest in the areas of electrode placement. If a female patient has large breasts, placing the electrodes under the left breast gives more accurate results.