Electrocardiogram (ECG or EKG) is a test that measures the electrical activity of the heartbeat. With each beat, an electrical impulse (or “wave”) travels through the heart. This wave causes the muscle to squeeze and pump blood from the heart. A normal heartbeat on ECG will show the timing of the top and lower chambers.
An ECG is a screening or diagnostic test. First, by measuring time intervals on the ECG, our doctors can determine how long the electrical wave takes to pass through the heart. Finding out how long a wave takes to travel from one part of the heart to the next shows if the electrical activity is normal or slow, fast or irregular. Second, by measuring wave form of electrical activity, it gives a lot of information. This information may be used to diagnose different conditions like heart attack, fluid collection around the heart etc or the information may suggest some abnormalities which will then need further evaluation by a cardiologist or by further tests. Further testing may involve stress test to find the blockages, echocardiogram to find structural abnormalities, holter test for heart rhythm etc.