Appropriate Cardiac Anatomy

Abstract

Various approaches, including inspection, palpation, percussion, auscultation, chest radiography, electrocardiography, echocardiography, computed tomography, cardiac magnetic resonance imaging, and other techniques for cardiac imaging, are the methodologies used to assess the inside of the heart from outside the body. It follows that exact knowledge of intrinsic cardiac anatomy is fundamental for accurate diagnosis. In addition, any kind of invasive cardiac procedure, requires an exact knowledge of cardiac anatomy so as to ensure safety of the investigation. In the light of the significant advances made in the resolution of the techniques for imaging now used by modern‐day cardiologists, far more detailed anatomical knowledge is required so as to obtain full value from the investigations. A basic knowledge of cardiac anatomy is initially achieved in the dissection lab. However, once the heart is removed from the donor, it is often oriented and studied in an attitudinally inappropriate manner when compared to its in‐situ orientation. This can lead to confusion and an incorrect understanding of the true location of cardiac components. For the purpose of not only maintaining, but improving the quality of anatomical knowledge, techniques based on modern cardiac imaging can provide a supplement to the dissection experience. In clinical settings, cardiac computed tomography can now provide ideal spatial resolution, at levels equal to or less than 0.5 mm. This permits the evaluation of the arrangement of even thin structures such as the valvar leaflets. Currently, by using datasets obtained from routine clinical scanning, all cardiologists have the ability to provide in‐depth three‐dimensional knowledge of intrinsic cardiac anatomy. This is achieved by interrogation of three‐dimensional reconstructions of multi‐planar two‐dimensional images, thus replicating real cardiac dissection. By means of such “virtual dissection”, the cardiac components can be shown in the blood‐filled living situation. By combining the reconstructed images, the anatomy of intrinsic features can be shown in relation to the pertinent surrounding extracardiac structures. Sections can be repeatedly acquired, using any desired plane viewed from multiple directions. Such “virtual dissection” is obviously performed without extracting the heart from the thorax, presenting an obvious advantage over the traditional cadaveric approach. All the analyses, furthermore, are performed in attitudinally appropriate fashion, without losing any of the coordinates relative to the components of the thoracic cage. Despite the obvious values of “virtual dissection”, it does not replace real dissection. It is the accurate knowledge based on real dissection that provides the basis for proper evaluation of the virtual images. This means that anatomists must themselves keep abreast of the advances made in modern clinical imaging. An appropriate collaborative approach between anatomists and cardiologists will self‐evidently continue to improve the educational values of the understanding of cardiac anatomy.