Narrator: An echocardiogram is a common test using sound waves to map out the shape and size of your heart, thus allowing your doctor to see how well your heart pumps blood and look for abnormalities of the heart valves and chambers. In a transthoracic echocardiogram, your sonographer will put a cool gel on your chest. Your sonographer will move a transducer firmly through the gel, sending painless sound waves to your heart. The sound waves bounce off your heart and echo back to the transducer. The sound waves are converted to moving images of your heart muscles, chambers, and valves on a video screen. A doppler echocardiogram records echoes from blood cells. The speed and direction of the blood flow indicate how well blood gets around inside your heart. A stress echocardiogram evaluates images of the heart before and after exercise, or following medication that simulates exercise on the heart. Comparing your echo results before and after activity provides your doctor information about certain heart problems, such as coronary artery disease, that may only occur with exertion. A transesophageal echocardiogram sends sound waves through a transducer passed gently down your throat while you are under sedation. This test provides a closer, more detailed evaluation of your heart.