Transesophageal Two-DimensionalEchocardiography: Comparisonof Ultrasonicand Anatomic Sections MICHAEL SCHLijTER, PhD, ANDREAS HINRICHS, MD, WOLFGANG THIER, MD, PETER KREMER, MD, SijREN SCHRijDER, MD, MICHAEL K. CAHALAN, MD, and PETER HANRATH, MD, With the technical assistance of VOLKER SIGLOW Conventional P-dimensional echocardiography has become a well-established tool for evaluating car- diovascular diseases. Recent introduction of 2- dimensional transesophageal echocardiography has widened the ultrasonic examination possibilities of the heart and great arteries. The 6 standard trans- esophageal transducer positions that have proved representative and of diagnostic value are de- scribed. To facilitate structure identification and interpretation of anatomic relations, transesopha- geal recordings were compared with corresponding anatomic sections. (Am J Cardiol 1984;53:1173-1178) Two-dimensional (2-D) echocardiography is an estab- lished tool in cardiology. Standard views are obtained from the apical, parasternal, subcostal and suprasternal transducer positions. The cardiac structures and their topographic interrelation are well-defined by compar- ative anatomic sections through the heart.‘v2 Recently, the diagnostic potential of 2-D echocardiography has been increased by the transesophageal approach.3-s Ultrasonic access to the heart from the esophagus is not restricted by lung tissue or ribs, and the vicinity of both organs allows the use of high-frequency, near-focused transducers, resulting in increased image quality. Cross-sectional images of the heart recorded from the esophagus are oriented differently and are therefore less familiar than transthoracic images. This report com- pares transesophageal echocardiographic sections with corresponding anatomic sections to facilitate structure identification and interpretation of anatomic relations from transesophageal recordings. Methods Transesophageal images are recorded by means of a min- iature phased-array transducer fixed at the tip of a gastro- From the Departments of Cardiology and Pathology, University Hospital Eppendorf, Hamburg, Federal Republic of Germany, and the Department of Anesthesia, University of California, San Francisco, California. Manuscript received August 2, 1983; revised manuscript received December 22, 1983, accepted December 26, 1983. Address for reprints: Peter Hanrath, MD, II. Med. Abteilung, All- gemeines Krankenhaus St. Georg, Lohmijhlenstrasse 5, 2000 Hamburg 1, Federal Republic of Germany. scope.6 The 32 single elements of the transducer head are ar- ranged so that only horizontal sections can be obtained. The various tomographic planes through the heart are achieved by translating and rotating the gastroscope within the esophagus (Fig. 1). Examination is performed with the patient lying supine. The gastroscope is introduced with the trans- ducer facing anteriorly. Identification of left-sided cardiac structures: zyxwvutsrqponmlk The aortic value uiew: At a level of 35 to 40 cm from the patient’s teeth, the first structure that is readily identified is the aortic root (Fig. 2A). The transducer position is slightly superior and inferior to the left atrium (position 1, Fig. l), so that the ul- trasonic beams transverse the uppermost portion of the left atrium, the aortic root and the right ventricular (RV) outflow tract, in that order. The ultrasonic sector image thus recorded correspondingly visualizes, from top (dorsal) to bottom (ventral), part of the left atria1 (LA) cavity, the circular shape of the aortic root and the RV outflow tract, transected in an oblique plane. With diastole, the aortic valve cusps coapt to form a characteristic, starlike echocardiographic appearance. Figure 2B shows a corresponding anatomic section. This view is well-suited to qualitative evaluation of the morphologic aspects of the aortic valve. Aside from minor individual variations, the aorta is transected roughly per- pendicular, giving it a circular echocardiographic appearance, and a bi-, tri- or quadricuspid configuration of the valve is readily established. Normally, the cusp commissures give rise to thin, distinct echoes, so that sclerotic, fibrocalcific or cal- cified valves can be recognized by the appearance of thick valvular echoes. However, these entities of valvular disease cannot be confidently differentiated nor can the severity of valvular stenosis be determined quantitatively. Therefore, we used this view mainly for “a quick look” at the aortic valve and as an excellent landmark for transducer orientation. zyxwvutsrqponmlk 1173