Echocardiography in Cardiac Surgery

Since 1976, echocardiography (echo) has been used to evaluate cardiac structure and function. Echo uses sound in the high-frequency range (2 to 10 MHz). Frequency ranges between 2 and 5 MHz are typically used for imaging adults, while frequencies of 7.5 to 10 MHz are used for children and specialized adult applications. The transducer contains a piezoelectric crystal that converts electrical to sound energy, producing sound waves that are transmitted in the form of a beam. A complete transthoracic echocardiogram (TTE) consists of a group of interrelated applications including two-dimensional (2D) anatomic imaging, M-mode, and three Doppler techniques: pulsed-wave (PW), continuous-wave (CW), and color-flow (CF) imaging.1–7 In addition, the quantification of cardiac chamber dimensions, areas, and volumes is an important aspect of a complete examination. Using a combination of these ultrasound techniques, one can assess the anatomy and function of the cardiac valves, myocardium, and pericardium.