Echocardiography is the ultrasound examination of the heart. Also known as “cardiac echo,” the examination method is noninvasive and very gentle, making it possible to detect heart defects even in unborn babies, who can then be treated while still in the womb.
What is echocardiography?
Echocardiography is the ultrasound examination of the heart. Also known as “cardiac echo,” the examination method is noninvasive and very gentle, making it possible to detect heart defects even in unborn babies. There are two different variants of echocardiography: TEE (transesophageal echocardiography) and TTE (transthoracic echocardiography). In TEE, the heart is examined by means of an endoscopic probe in which an ultrasound probe is integrated. The probe is inserted through the esophagus of the fasting patient. In contrast, with TTE, the examination is performed from the outside via the chest. In this method, the patient is examined in a slight left-sided position with the upper body slightly elevated using a small transducer that is placed at different positions in the chest area. When the abbreviated word “echo” is used, it usually refers to the second form of echocardiography.
Function, application, effect, and goals
Echocardiography can show a real-time image of the heart. It is of great importance in assessing the size of the heart and its function. With this procedure, all the motions of the heart, including the functioning of the heart valves, can be directly visualized. The sizes of the atria, ventricles and heart valves can be measured and it can be assessed whether all areas of the heart walls are cooperating regularly with the heartbeat and whether the opening and closing of the heart valves is taking place at the right time or whether they are narrowed or leaking. Different imaging methods are used in echocardiography: the one-dimensional M-mode method, the two-dimensional B-mode method and color-coded two-dimensional duplex sonography. In color-coded echocardiography, blood flow toward the transducer is displayed as a red cloud, while flow away from the transducer is displayed as a blue cloud. This allows the direction of blood flow to be seen. Furthermore, this type of display can be used in an echocardiogram to estimate how large a leak is present. Thanks to special techniques such as Doppler echocardiography, it is also possible to determine the speed of the blood. By measuring the flow velocity and detecting flow accelerations, it is possible to investigate whether there is normal function of the heart valves or whether there is stenosis or leakage. Another form is stress echocardiography, which allows assessment of cardiac function under stress and can provide clues to coronary artery disease or disease of the heart muscle. For this purpose, cardiac activity is increased prior to echocardiography either by means of physical exertion or by a drug. Depending on the procedure used, echocardiography allows a wide variety of statements to be made about the condition and function of the heart. For example, the size of the heart cavities (atria and ventricles) and the thickness of the walls and septum of the heart can be determined. The assessment of the pumping function or the performance of the heart is also possible. These are used, for example, to assess the extent of heart failure. Movement disorders of the heart, which can occur as a result of a heart attack, can also be detected on echocardiography. The function and shape of the heart valves and the diameter and shape of the aorta can also be measured, as can changes in the pericardium, especially the size and extent of a pericardial effusion. Blood pressure in the pulmonary artery, elevated values of which may indicate pulmonary hypertension or pulmonary embolism, for example, can also be assessed. In addition, echocardiography makes it possible to detect congenital heart malformations at an early stage.
Risks and dangers
In general, the risks associated with echocardiography are low. The standard external method poses no dangers and is not uncomfortable. With transesophageal echocardiography, unpleasant phenomena such as gag reflex and increased salivation cannot always be avoided, as these are completely natural reactions of the body to a foreign body, in this case the probe.During the examination, side effects may occur in some cases due to the local anesthetics administered. Less frequently, vessels, tissues or nerves are injured when the tube is pushed through the esophagus. Injury to the pharynx and esophagus and subsequent bleeding and infection are considered the main risks associated with echocardiography. However, when carefully considered by the physician, the benefits of examination by echocardiography outweigh any complications that may occur many times over.