FIG 19.4 Short-axis section of the ventricular mass viewed from the apex looking toward the base Note the deeply wedged position of the aortic valve between the mitral valve and the septum, with fibrous continuity between the valvar leaflets in the roof of the ventricle In contrast, the supraventricular (SV) crest forms the roof of the right ventricle, interposing between the leaflets of the tricuspid and pulmonary valves FIG 19.5 Short-axis section taken closer to the base than the one shown in Fig 19.4 Epicardial fat interposes between the wall of the right atrium and the crest of the ventricular septum at the anatomic crux The echocardiographic crux is seen in so-called four-chamber planes, as shown by the yellow line Anatomic Principles of Echocardiography Echocardiographic imaging of the heart is obstructed by both bony structures and the air-filled lungs Unobstructed views can generally be obtained from the cardiac apex, from alongside the sternum through the intercostal spaces, from beneath the rib cage, and from the suprasternal notch (Fig 19.6) Different factors can interfere with obtaining the standardized imaging views such as body size and lung interference Especially in adult postoperative patients, windows can be very limited and additional imaging techniques may be required to obtain the information required Transesophageal echocardiography allows visualization of the cardiac structures from the esophagus and stomach but is a more invasive technique that requires general anesthesia in children Other imaging modalities like cardiac magnetic resonance imaging may be useful complementary techniques A standard full echocardiographic protocol has been proposed for pediatric scanning combining different windows and views.5 (Lai et al.) A full pediatric study requires combining all windows and views to reconstruct the entire morphology and assess valve and ventricular function Standard echocardiographic views are well established for patients with normally located hearts but can challenging in patients with abnormal position of the heart within the chest such as dextrocardia, with or without mirror-image atrial arrangement This often requires using nonstandard positioning of the probe keeping the orientation of the probe so that the position of the heart within the chest is correctly displayed (especially left-right orientation) The position of cardiac structures in the chest is described using the patient's coordinate system as a reference (patient's left-right, superior-inferior, anterior-posterior) Orthogonal imaging planes are described relative to the body axis as coronal, sagittal, and transverse, but it should be mentioned that the axis of the heart rarely corresponds to the axis of the body (see Fig 19.1) As the echocardiographer obtains the images based on the cardiac axis, it is more relevant to describe the images relative to the cardiac axis Of the three cardiac orthogonal planes, two are in the long axis of the heart itself (parasternal longaxis and apical views), the other being in the cardiac short axis (Fig 19.7) Simple geometric principles dictate that, from any given window, it is possible to obtain only two of these basic planes, although intermediate cuts can be taken toward the third plane FIG 19.6 Location of the echocardiographic windows that permit visualization of cardiac anatomy ... A standard full echocardiographic protocol has been proposed for pediatric scanning combining different windows and views.5 (Lai et al.) A full pediatric study requires combining all windows and views to