The echocardiogram, or echo, is a noninvasive test that provides cardiologists with a survey of the heart using the same ultrasound technology used for pregnant women.

The test is performed by a technician called a sonographer, who spreads a gel over the chest to make sure that the ultrasound camera maintains good contact with the skin. During the exam, the sonographer will take still pictures of the heart, record video of the heart beating and examine the direction of blood flow.

The echocardiogram allows cardiologists to examine the size of a patient's heart and the condition of the patient's valves to determine how efficiently the heart contracts. Echos also reveal common congenital problems and possible causes of murmurs, palpitations, chest pain and shortness of breath.

An echocardiogram may be performed for further evaluation of signs or symptoms that may suggest:

Based on the results of this 20- to 30-minute test, cardiologists determine if more invasive tests are needed.