Echocardiography Imaging Techniques

The basic concept of echocardiography was first demonstrated by Lazzaro Spallanzani in the 18 century when he described the reflected echoes of inaudible sound.  Hertz and Edler reported the first use of ultrasound in the cardiac evaluation and continuous monitoring of heart movements in 1954. They used an industrial ultrasonic flaw detector and obtained time-varying echoes transcutaneously from the heart. The assessment of the mitral valve with the help of M-mode was the first clinical application of an echocardiogram.  Since then, echocardiography has expanded tremendously and exponentially over the decades and has become an integral part of cardiac evaluation. Although echocardiography started with B-mode, with the discovery of new technologies, including Doppler and 3-dimensional imaging, the echocardiographic examination has progressively become longer and more comprehensive. With the advent of echocardiographic contrast media and transesophageal probes, the sensitivity of echocardiographic examination has improved significantly, and it has become an important part of cardiac surgical procedures involving valvular reconstruction.  In some aspects, new technologies have completely replaced old methods. In other circumstances, new technologies have been incorporated to enhance existing capabilities. Even in the contemporary era of newer imaging modalities, an echocardiogram is recommended as the first choice for structural and functional assessment of the heart. This chapter aims to review the basics of ultrasound physiology, important terms used in echocardiography, different echocardiographic techniques, and basic echocardiographic views.