An echocardiogram, often referred to in the medical community as a cardiac ECHO or simply an ECHO, is a sonogram of the heart. (It is not abbreviated as ECG, which in medicine usually refers to an electrocardiogram.) Also known as a cardiac ultrasound, it uses standard ultrasound techniques to image two-dimensional slices of the heart. The latest ultrasound systems now employ 3D real-time imaging.
In addition to creating two-dimensional pictures of the cardiovascular system, an echocardiogram can also produce accurate assessment of the velocity of blood and cardiac tissue at any arbitrary point using pulsed or continuous wave Doppler ultrasound. This allows assessment of cardiac valve areas and function, any abnormal communications between the left and right side of the heart, any leaking of blood through the valves (valvular regurgitation), and calculation of the cardiac output as well as the ejection fraction. Other parameters measured include cardiac dimensions (luminal diameters and septal thicknesses) and E/A ratio.
Echocardiography was an early medical application of ultrasound. Echocardiography was also the first application of intravenouscontrast-enhanced ultrasound. This technique injects gas-filled microbubbles into the venous system to improve tissue and blood delineation. Contrast is also currently being evaluated for its effectiveness in evaluating myocardial perfusion. It can also be used with Doppler ultrasound to improve flow-related measurements (see Doppler echocardiography).
Echocardiography is performed by cardiac sonographers, cardiac physiologists (UK) or doctors trained in cardiology.
Three-dimensional echocardiography
3D echocardiography is now possible, using an ultrasound probe with an array of transducers and an appropriate processing system. This enables detailed anatomical assessment of cardiac pathology, particularly valvular defects, and cardiomyopathies. The ability to slice the virtual heart in infinite planes in an anatomically appropriate manner and to reconstruct Three-dimensional images of anatomic structures make 3D echocardiography unique for the understanding of the congenitally malformed heart. Real Time 3-Dimensional echocardiography can be used to guide the location of bioptomes during right ventricular endomyocardial biopsies.
The 3D Echo Box developed by the European Association of Echocardiography offers a complete review of Three Dimensional Echocardiography.
The 3D Echo Box developed by the European Association of Echocardiography offers a complete review of Three Dimensional Echocardiography.