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This chapter on cardiac anatomy takes a practical approach for operators who are going to perform various procedures associated with structural heart disease. Rather than assume the traditional approach of describing the gross anatomy of the heart in isolation from the procedures performed, this chapter will attempt to provide useful information (Tips and Tricks) of how the anatomy, as seen by the percutaneous operator, affects the procedure results. Therefore, the emphasis is not only on gross anatomy, but also the anatomy that the interventionalist perceives using different imaging modalities. Whereas a surgeon can see and touch the anatomic structures, a cardiac interventionalist has to rely on indirect methods of visualization, which include fluoroscopy, echocardiography, and intracardiac ultrasound. Magnetic resonance or computed tomography images can be useful for orientation and diagnosis before the procedure (and, more recently, can be used as an overlay on the fluoroscopy monitor in the catheterization lab). However, the focus of this chapter is what the interventionalist has at his or her disposal at the time of the procedure to understand the anatomy. Accurate use of available imaging modalities in the catheterization laboratory and appreciation of relative orientations are important for optimal device sizing and placement.
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Fluoroscopy provides a familiar image with the right atrium adjacent to the spine in the anteroposterior (AP) view, to the right in left anterior oblique (LAO) angulation, and anterior to the spine in the right anterior oblique (RAO) projection. The left upper pulmonary vein is just superior to the left atrial appendage and extends outside the cardiac shadow (Fig. 3-1). Transesophageal echocardiography (TEE) provides an image with the left atrium at the top of the screen because it is the closest structure to the probe, whereas the anterior cardiac structures, including the right atrium, are at the bottom of the screen. The left side of the image represents the inferior aspect of the heart leading to the inferior vena cava (IVC), and the right represents the superior aspects, including the superior vena cava (SVC) and aorta, all of which are not presented in the same orientation as the physical anatomy (Fig. 3-2). Rotating a TEE image 90° counterclockwise will orient the image similarly to a fluoroscopic image but with the plane of the image originating posteriorly from the esophagus to the anterior chest. The intracardiac echocardiography (ICE) probe is situated typically in the right atrium facing the atrial septum. The structure closest to the probe, and therefore at the top of the screen, is the right atrium. Similarly to TEE, the IVC is to the left of the screen, and the SVC is on the right. Rotating the ICE image 90° counterclockwise will present an image in the same anatomic orientation as fluoroscopy (see Fig. 3-1). TEE provides multiple tomographic cuts of the heart from different planes and angulations, which can be confusing for the interventionalist with a ...