About Video

This high-quality audio-recording performing an echocardiogram technique. In recent years, the application of ultrasound has increased exponentially, in several fields of clinical medicine. In fact, ultrasonography is today accepted as the fifth dimension of clinical examination after inspection, palpation, percussion and auscultation. Echocardiography is the application of ultrasound to examine the heart. It is a practical, noninvasive, cost-effective and reliable investigative tool. More and more physicians are these days performing or requesting for an echo to diagnose or exclude cardiac disease. An echo is performed for the diagnosis and assessment of virtually all forms of heart disease including congenital defects, valvular diseases, coronary heart disease, myocardial problems and pericardial disorders. Echo provides substantial amount of anatomical and physiological information. While still-frames or frozen images provide structural details, dynamic or real-time images convey functional abnormalities. Hemodynamic parameters that can be measured by echo are stroke volume, cardiac output, ejection fraction and pulmonary artery pressure. The modalities of echo used are two-dimensional (2-D), motion-mode (M-mode) and Doppler echo. Doppler echo includes pulsed-wave (PW), continuous-wave (CW) and color-flow map (CFM). All modalities follow the same principle of ultrasound but differ in terms of the manner in which the reflected signal is analyzed and displayed. They are not mutually exclusive but complement each other. Echocardiography is generally performed from the transthoracic route (TTE). If this is technically difficult due to the presence of obesity, emphysema or chest deformity, transesophageal echo (TEE) is performed. For transthoracic echo (TTE), specific areas on the chest are used, which are known as the standard echo windows. Standard echo windows are left parasternal, apical, subcostal and suprasternal. At these areas, there is minimum interference from ribs and lungs. Standard echo windows allow comparison between serial echoes performed in the same patient on different occasions. For echocardiography, the patient is asked to lie on his left side with the right arm placed along the body and the left arm tucked under the head. The transducer houses several piezoelectric crystals that transmit ultrasound waves, which are reflected back and analyzed. The transducer (probe) is smeared with insulating jelly and placed on the chest. It has a mark or dot that orients the probe. The probe is angulated anteriorly or posteriorly to bring the area of interest into focus and rotated clockwise or counter-clockwise to fine-tune the image. Images acquired from different echo windows are used to mentally construct the structure of the heart and to prepare a comprehensive report. During echocardiography, transducers having different frequencies are used. One has to strike a balance between resolution and penetration. Low frequency probes (3.5 MHz) provide good penetration but low resolution. They are used to evaluate deep structures and in adult subjects. High frequency probes (7.5 MHz) provide low penetration but good resolution. They are used to evaluate superficial structures and in children. The intensity of reflected ultrasound depends upon the tissue that reflects it. Bone is white, myocardium is gray and air or blood appears black. On the display screen, the image appears in the shape of a triangle. The probe is at the apex of the triangle from which multiple lines emerge. Accordingly, superficial structures appear on the upper portion of the screen while deep structures appear on the lower portion of the screen.