WHAT IS ECHOCARDIOGRAPHY (ECHO, HEART SONOGRAM, HEART ULTRASONOGRAM) TEST?
Echocardiography is a noninvasive, acoustic imaging procedure that determines the size, shape, position, thickness, and movements of the heart valves, walls, and chambers during each cardiac cycle. It records the echoes created by the deflection of short pulses of an ultrasonic beam off the cardiac structures onto an oscilloscope. The time required for the ultrasonic beam to be reflected back to the transducer from differing densities of tissue is converted by a computer to an electrical impulse displayed on an oscilloscopic screen to create a two-dimensional picture of the heart in different projections. The resolution of the oscilloscope recording obtained is determined by the frequency of the beam. Lower frequencies penetrate further but provide less resolution than higher frequencies. Echocardiography can also be performed transesophageally (TEE) with the transmitter inserted into the oesophagus similar to an endoscope. This gives a clearer view of the valves and endocardium, especially in the presence of obesity or severe chronic obstructive pulmonary disease (COPD).