Electrocardiography (ECG or EKG)

Electrocardiography (ECG or EKG) 

Electrocardiography (ECG or EKG) is a common diagnostic test used to record the heart’s electrical signals. The result, which is produced in graphical format, is known as an electrocardiogram. Contractions in different areas of the heart are coordinated by natural electrical impulses, which help to maintain proper blood flow. An electrocardiogram can help a physician evaluate how fast the heart is beating, the rhythm of the heartbeats and the strength and timing of the electrical impulses. Changes in EKGs performed over time may be a sign of a heart-related condition, such as coronary artery disease. 

Conditions Diagnosed 

A physician may order an electrocardiography test to investigate: 

  • Abnormal heart rhythms (arrhythmias) 
  • Symptoms such as chest pain, dizziness, shortness of breath, a rapid pulse and unexplained fatigue in a patient who is at risk for heart attack 
  • Whether a heart attack has occurred 
  • Whether a narrowing or blockage in a coronary artery is the cause of chest pain or a heart attack  
  • The effectiveness of a medication, a pacemaker or another heart disease treatment 

Procedure Details 

During an electrocardiography test, the patient lies on a bed or examination table. A technician will apply up to 12 adhesive sensors to the patient’s chest and limbs. The sensors will record the electrical signals that cause the heart to beat, then send that information to a computer, which will convert it to graphical format and display the graph on a nearby screen or paper printout. An EKG takes only a few minutes to complete, and the patient can resume his or her normal activities immediately afterward. 

What to Expect 

No advance preparation is needed for electrocardiography, which is a relatively quick and safe procedure. The electrodes do not produce an electrical current; instead, they simply record the electrical impulses generated by the heart. 


Diagnostic testing plays a key role in the detection and management of all forms of cardiovascular disease. Electrocardiography, in particular, can provide a physician with valuable insight into a patient’s heart health, as well as clues about potential problems. Tampa General Hospital’s Heart & Vascular Institute is a convenient source of electrocardiography and other forms of testing.