Echocardiography is a method of examining the heart. Here the heart is visualized by an ultrasound. This makes echocardiography, along with electrocardiography (ECG), one of the most important, non-invasive examinations of the heart.
The various echocardiographic procedures (transthoracic echocardiography, transesophageal echocardiography and exercise echocardiography) are not only used to diagnose cardiac diseases, but also to monitor the progress of the disease. For example, both valvular heart disease and myocardial insufficiency are checked by echocardiography approximately every six to 12 months. Even after heart surgery, the function of the heart is checked by echocardiography.
The control examination is performed in the same way as previous echocardiography examinations. During this control echocardiography, special attention is paid to any deterioration in heart function. Deterioration of heart function can be seen, for example, by a decrease in pumping function or by an enlargement of the heart due to heavy exertion.
Heart monitoring can be performed on an outpatient basis in special centers. This means that the patient can go home again after the examination. Stress echocardiography (“stress echo”) is used in particular to monitor the course of coronary heart disease (CHD).
In coronary artery disease, changes occur in the coronary arteries that supply blood to the heart muscle. In the worst case, a coronary artery can become completely blocked, which is why regular check-ups are necessary. A worsening of coronary artery disease occurs if abort criteria, such as reaching the target heart rate or the occurrence of chest pain, are reached earlier than in the previous exercise echocardiography examination.
Research methods
There are several ways to perform echocardiography. The standard method is transthoracic echocardiography (TTE). Here, the ultrasound probe is placed on the chest and the heart is observed.
It is also possible to assess the heart through the esophagus. This is called transesophageal echocardiography (TEE). Another examination method is the ultrasound examination of the heart under stress.
Transthoracic Echocardiography (TTE)
This form of echocardiography is the standard examination and is known by the short word “echo”. First the heart is examined by placing the ultrasound probe on the chest. The two most important positions of the ultrasound probe are parasternal, i.e.
to the left of the sternum, and apical, i.e. from the tip of the heart. Through further starting points, such as the right under the ribs (subcostal), the large liver vein can be viewed. The ultrasound probe can also be placed above the sternum to obtain a wider view of the heart.
The heart and its function can be assessed by making various settings on the ultrasound machine. In the 2-D image, the heart function is visible in real time as a black and white sectional image. In particular, the size of the heart chambers, the function of the valves and the pumping function of the heart can be displayed very well.
Thus the ejection performance of the heart (ejection fraction) can be determined. In a longitudinal section or by viewing suprasternally (above the sternum), the aorta and the aortic arch can be viewed, for example to identify the life-threatening disease of aortic dissection. The M-mode is used for the one-dimensional representation of motion sequences.
Thus, the movements of the aortic and mitral valve can be displayed on a one-dimensional, horizontal line. The pumping function of the left ventricle (left ventricle) can also be visualized. The PW- and CW- Doppler represent a one-dimensional procedure for the application of the Doppler effect.
The Doppler effect can be used to measure blood flow velocities. Hereby, heart valve defects, constrictions (stenoses) or short circuit connections (shunts) can be detected. The color Doppler effect allows the venous and arterial flow to be separated by color. In this way, especially valve insufficiencies or stenoses, but also shunt connections can be displayed and localized in color.
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