What is the name of the test that measures the electrical activity of the heart?

What is the name of the test that measures the electrical activity of the heart? The answer is an electrocardiogram. Commonly abbreviated ECG, or EKG, it records the heart’s electrical signals through electrodes placed on the skin.

A standard 12-lead ECG usually uses 10 electrodes positioned on the limbs and chest. The machine measures electrical voltage from 12 different viewpoints and prints or displays the results as a tracing over time. The pattern reflects the orderly spread of electrical activation through the heart muscle.

The main features of a normal tracing include the P wave, which represents atrial depolarization; the QRS complex, which represents ventricular depolarization; and the T wave, which represents ventricular repolarization. Clinicians use these patterns to evaluate heart rate and rhythm and to look for signs of arrhythmias, heart-muscle damage, ischemia, electrolyte disturbances, or medication effects.

An electrocardiogram is not the same as an echocardiogram. An ECG measures electrical activity, while an echocardiogram uses ultrasound to create images of the heart’s structures and pumping action. The name EKG comes from the German Elektrokardiogramm and helps distinguish it from EEG, which measures brain activity.