Final answer:
Echocardiography is the use of ultrasound to create an image of the heart's structure, and is known for being the least invasive imaging technique, which makes it safe for use in pregnancy and for diagnosing various heart conditions.
Step-by-step explanation:
The use of ultrasound to produce a picture of the heart's structure is known as echocardiography. This diagnostic tool creates an image by using high-frequency sound waves that are transmitted into the body. These sound waves generate an echo signal, which is then converted into a real-time image of the heart's anatomy and physiology. While an electrocardiogram (ECG or EKG) records the electrical activity of the heart, echocardiography is more about visualizing the heart's internal structure, including its valves and chambers.
Echocardiograms are particularly useful as they are sonograms of the heart that can assist in diagnosing a variety of heart pathologies, such as valve disorders. This imaging technique is the least invasive and is used in sensitive situations, including during pregnancy, because it does not use ionizing radiation and can be performed safely.