An electrocardiogram, also called EKG or ECG, gives physicians specific information about the electrical activity of the heart by recording its rhythms and patterns. An electrocardiogram helps to diagnose heart conditions. During an emergency situation, this test can determine if you are having a heart attack. 

When your heart beats, electrical waves move through it. These impulses help to coordinate muscle contraction to cause your heart to pump blood. Electrocardiograms record how long it takes for electrical waves to move through your heart, if the waves are too slow or irregular and if areas of your heart aren’t working properly. Electrocardiograms are usually performed in a clinical setting, although sometimes physicians prescribe a portable cardiac event monitor that patients wear at home. 

What to expect during an electrocardiogram