Discover the ESC Textbook of Cardiovascular Imaging 2nd edition
standardized data acquisition in transthoracic echocardiography 7 intra- and inter-observer variability is reduced. The basis for the correct configuration of an echocardiographic data acquisition and examination—including data acquisition, data documentation, data storage, interpretation and reporting of the results—as well as the correct measurements and calculations of numerical values in echocardiography is provided by already published national and international guidelines and position papers. Fig. 1.5 With the transducer holding of the parasternal long-axis view the hand is slid down to the apical long-axis view (a). At the position of the apical long-axis view the fourth and fifth finger still remain on the skin. In addition, the complete ulnar area of the fifth finger is placed in position against the thorax for scanning from the apical approach (a). This transducer holding is linked with the apical long-axis view (b). A clockwise rotation of 60° without tilting and flipping has to be done (c) to get the correct apical 2-chamber view (d). Standardized data acquisition in transthoracic echocardiography Left parasternal and apical scanning should normally be performed in left lateral position of the patient. The transthoracic echocardiographic examination should start with the correct documentation of the conventional twodimensional left parasternal long-axis view of the left ventricle ( Fig. 1.6a–b). This sectional plane is characterized by the centre of the mitral valve, the centre of the aortic valve, as well as by the ‘imaginary’ cardiac apex, which cannot be visualized from the parasternal approach due to the superposition of the left lung. The following anatomical structures are visualized by the parasternal long-axis view. In the nearfield of the transducer, the first myocardial structure is the free right ventricular Fig. 1.6 Standardized grey-scale parasternal long-axis view during systole (a) and diastole (c), as well as the corresponding colour-coded images during systole (b) and diastole (d). Additional comments in the text.
8 chapter 1 conventional echocardiography—basic principles Fig. 1.7 Illustration for display of the right ventricular inflow tract and right ventricular outflow tract. Starting from the standardized parasternal long-axis view (red arrow and red surrounding), the right ventricular inflow tract is displayed by medial tilting (green arrow and green surrounding) of the sectional plane (a-systole, b-diastole), the right ventricular outflow tract by lateral tilting (blue arrow and blue surrounding) of the sectional plane (c-systole, d-diastole). The corresponding colour-coded views are displayed in e-h. Additional comments in the text. wall—normally parts of the right ventricular outflow tract. The left ventricular cavity in the longitudinal section is surrounded by the midbasal anteroseptal and posterior regions of the left ventricle. The mitral valve is sliced in the centre of the valve plane nearly perpendicularly to the commissure. The aortic valve is also sliced in the centre of the valve in longitudinal direction. The aortic root and the proximal part of the ascending aorta are longitudinally intersected. Behind the aortic root the left atrium is longitudinally intersected. The posterior left ventricular wall is bordered by the posterior epicardium and the diaphragm. The far field of the parasternal long-axis view should include the cross-section of the descending aorta behind the left atrium. A standardized left parasternal long-axis view can be verified by the following display of the heart within the sector. The mitral valve has to be centred in the scanning sector. Then, the ventral boundary of the mid anteroseptal region of the left ventricle on the left side has to be in line with the ventral boundary of the ascending aorta on the right side of the sector. Furthermore, the check of the correct longitudinal parasternal long-axis view should include the ascending aorta visualized as a tube and not as an oblique section, the central valve separation of the mitral and aortic valves, as well as the missing of papillary muscles. If papillary muscles are sliced, the sectional plane is not in the centre of the left cavity, which corresponds to a non-standardized view. For qualitative assessment of flow phenomena at the mitral and aortic valves, as well as for the detection of perimembranous ventricular septal defects, a colour-coded 2D cineloop of the left parasternal long-axis view can be added to the documentation ( Fig. 1.6c–d). With respect to the documentation of the right heart, tilting the transducer to the sternal regions enables the visualization of the right ventricular inflow tract with a longitudinal sectional plane through the tricuspid valve ( Fig. 1.7a–b). Tilting the long-axis view to the lateral regions of the heart enables the visualization of the right ventricular outflow tract with the longitudinal sectional plane through the pulmonary valve ( Fig. 1.7c–d). These views should also be documented using colour-coded 2D cineloops ( Fig. 1.7e–h). The 90° clockwise rotation of the transducer from the transducer position of the correctly set parasternal long-axis view will lead to sectional short-axis views of the heart. The correct transducer position to display standardized parasternal shortaxis views using conventional transthoracic echocardiography is documented by a M-mode sweep ( Fig. 1.8a). Parasternal short-axis views should be documented with respect to an accurate definition of the plane according to cardiac structures, which enables a high reproducibility of each view. Short-axis views are defined by the accurate cross-section through the left ventricular attachment of the papillary muscles ( Fig.1.8b), through the papillary muscles ( Fig. 1.8c), through the chord