Heart Rhythms on ECG

The heart’s electrical system triggers the heartbeat. Each beat of the heart is represented on the electrocardiogram (EKG or ECG) by a wave arm.

Your doctor uses the ECG to:

• assess your heart rhythm
• diagnose poor blood flow to the heart muscle (ischemia)
• diagnose a heart attack
• diagnose abnormalities of your heart, such as heart chamber enlargement and abnormal electrical conduction

To prepare

• Avoid oily or greasy skin creams and lotions the day of the test. They interfere with the electrode-skin contact
• Avoid full-length hosiery, as electrodes need to be placed directly on the legs.
• Wear a shirt that can be easily removed to place the leads on the chest.

What to expect

• During a resting ECG, a technician will attach 10 electrodes with adhesive pads to the skin of your chest, arms and legs. Men may have chest hair shaved to allow a better connection. You will lie flat while the computer creates a picture, on graph paper, of the electrical impulses traveling through your heart.
• It takes about 10 minutes to attach the electrodes and complete the test, but the actual recording takes only a few seconds.
• Your ECG patterns will be kept on file for comparison with future ECG recordings.
• If you have questions, ask your doctor.

The normal heart rhythm (normal sinus rhythm) shows the electrical activity in the heart is following the normal pathway. The rhythm is regular and the node is normal (about 50 to 100 beats per minute).