An electrocardiogram (ECG) is a test that records the electrical activity of the heart. ECG is used to measure the rate and regularity of heartbeats as well as the size and position of the chambers, the presence of any damage to the heart, and the effects of drugs or devices used to regulate the heart (such as a pacemaker).
An echocardiogram is a graphic outline of the hearts movement. During an ECG test, high-frequency sound waves that come from a hand-held wand placed on your chest, is used to provide pictures of the heart’s valves and chambers and help the sonographer evaluate the pumping action of the heart.
Echo is often combined with Doppler ultrasound and color Doppler to evaluate blood flow across the heart’s valves.
A stress test, sometimes called a treadmill test or exercise test, helps a doctor find out how well your heart handles work. As your body works harder during the test, it requires more oxygen, so the heart must pump more blood.
The test can show if the blood supply is reduced in the arteries that supply the heart.