Echocardiography is the imaging of the heart using ultrasound. The common ultrasound techniques are used to image two-dimensional slices of the heart. Apart from 2-D, traditional echocardiography also utilises M-mode and Doppler. Color Doppler is used to take images of flowing blood. Continuous wave Doppler and Pulsed wave Doppler are used to measure the speed of flowing blood. There have been many developments in the field of echocardiography lately, such as real time 3-D imaging, tissue Doppler and several specialized techniques.

The usual echocardiogram is also termed a transthoracic echocardiogram, or TTE. In TTE, images of the heart are taken from outside through the chest wall. The echocardiography probe is placed on the chest wall of the subject and images are clicked. This is a simple, yet totally accurate test. There is also another method to perform an echocardiogram. In that method, a specialized endoscope containing an echocardiography transducer is inserted into the patient's esophagus to record pictures from there. This is known as a transesophageal echocardiogram or TEE. TEE has a great advantage in that it gives even better images. This is because the transducer is more close to the heart. Some of the posterior structures of the heart can be imaged much better with TEE. These structures include the aorta, the pulmonary artery, the valves of the heart, and the left atrium. TEE requires sedation and a local anesthetic lubricant for the esophagus and can be uncomfortable for the patient.

Echocardiography

In addition to creating two-dimensional pictures of the cardiovascular system, an echocardiogram can also produce precise assessment of the velocity of blood and cardiac tissue at any given point with help of pulsed or continuous wave Doppler ultrasound. This enables 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 and ejection fraction.

Echocardiography was an early medical application of ultrasound and also the first application of intravenous contrast-enhanced ultrasound. This method administers gas-filled microbubbles into the venous system to improve tissue and blood delineation. It is performed by cardiac sonographers or doctors well-trained in cardiology.

Echocardiography is applied to diagnose cardiovascular diseases. It can provide lots of helpful information, for instance the size and shape of the heart, its pumping function and the location and extent of any scarring of the tissues. It is immensely useful for assessing diseases of the heart valves. It can detect abnormalities in the pattern of blood flow, such as the backward flow of blood through partly closed heart valves. By studying the motion of the heart wall, echocardiography can spot the presence and assess the severity of coronary artery disease, and also ascertain if any chest pain is related to heart disease. Echocardiography is also able to detect hypertrophic cardiomyopathy. The greatest advantage is that it is noninvasive and has no known side effects.

3-dimensional echocardiography

3-D echocardiography has now been made possible, with the help of an ultrasound probe with an array of transducers and an appropriate processing system. So detailed anatomical assessment of cardiac pathology is possible, particularly valvular defects, and cardiomyopathies.  The ability to slice the virtual heart in infinite planes in an anatomically accurate manner and to reconstruct 3-dimensional images of anatomic structures make 3D echocardiography incredible for the understanding of the congenitally malformed heart.