Echocardiography, or echo, is a painless test that uses sound waves to create pictures of your heart.
The test gives your doctor information about the size and shape of your heart and how well your heart's chambers and valves are working. Echo also can be done to detect heart problems in infants and children.
The test also can identify areas of heart muscle that aren't contracting normally due to poor blood flow or injury from a previous heart attack. In addition, a type of echo called Doppler ultrasound shows how well blood flows through the chambers and valves of your heart.
Echo can detect possible blood clots inside the heart, fluid buildup in the pericardium (the sac around the heart), and problems with the aorta. The aorta is the main artery that carries oxygen-rich blood from your heart to your body.
This answer from the National Heart, Lung and Blood Institute has been reviewed and/or edited by Dr. William D. Knopf.