Echocardiography is a test that uses sound waves to produce live images of your heart. The image is called an echocardiogram. This test allows your doctor to monitor how your heart and its valves are functioning. The images can help them get information about: blood clots in the heart chambers. An echocardiography, echocardiogram, cardiac echo or simply an echo, is an ultrasound of the heart. Echocardiography uses standard two-dimensional, three-dimensional, and Doppler ultrasound to create images of the heart.