Dynamic three-dimensional transesophageal echocardiography using a computed tomographic imaging probe--clinical potential and limitation

[Improved structure identification with tissue Doppler echocardiography]

Tissue Doppler echocardiography (TDE) has been shown to be of particular value in patients with impaired myocardial function. Recently, the technique was successfully employed to localize the ventricular insertion of accessory atrioventricular pathways. The identification of abnormal cardiac structures is coming up now as a new field of clinical interest. The purpose of this study was to differentiate anomalous cardiac and aortic from native structures by physical properties of tissue motion using transesophageal TDE. Characteristic motion patterns of anomalous structures have not been described in detail and tissue Doppler findings have not been associated with clinical features up to now. Forty consecutive patients were included after anomalous cardiac or vascular structures had been detected by conventional transesophageal echocardiography (TEE). A control group consisted of 20 subjects. Rapidity of diagnosis in anomalous structures was divided into 3 categories, and TDE signals were related to particular pathology by a blinded, 2nd observer. Three different motion patterns could be defined: incoherent motion due to free oscillation of an anomalous structure which is independent of the surrounding tissue (Figure 1b); coherent motion with a phase difference meaning that motion depends on the motion of the surrounding tissue but is out of phase (Figure 2); concordant motion showing no difference in direction, velocity, or phase of motion compared with the surrounding tissue. Incoherent motion was present in endocarditic vegetations, 4th degree aortic plaques, Chiari network, valvular prolapse, intracavitary tumors, and freely oscillating thrombi as well as in normal valve leaflets and papillary muscles. Especially if endocarditic vegetations are present its incoherent motion facilitates to recognize these small structures. The colorcode of this motion pattern demarcates the vegetation reliably from the surrounding tissue (Figure 1b). Within 15 seconds vegetations could be detected in 9 (82%) vs 2 (18%) patients employing only conventional imaging. Using conventional echocardiographic approaches detection of vegetations is frequently hindered by their small size and minor echo intensity (Figure 1a). In contrast, size and echo intensity do not affect the tissue Doppler signal. Normal papillary muscles and distal portions of the mitral and tricuspid valves were demonstrated to regularly meet the criterion of incoherent tissue motion in the control group. In part, this was also observed with respect to the aortic and pulmonary valves. In valvular tissue incoherent motion was caused by passive floating, whereas papillary muscles show an active inverse motion for short time intervals. Nevertheless, physiologic incoherent motion did not lead to any false differential diagnosis. The phase difference of coherent motion results from damped oscillation. This phenomenon was visualized by tissue Doppler M-mode in 5 thrombi of the left atrial appendage (LAA) (100%) and in 1 ventricular thrombus (50% of all clots). Concordant motion was shown in 3rd degree aortic plaques and postrheumatic and calcified vegetations. These structures were found to be completely embedded or closely attached, so that their passive motion corresponded to the motion of the surrounding regular tissue. Detection and assessment of anomalous structures are based on their motion patterns which can be synchronous or asynchronous in comparison with the surrounding tissue. Another goal of this investigation was to test if the sensitivity of TEE to spontaneous echo contrast can be improved using TDE. In 21 patients presenting with left atrial dilation (left atrial diameter > 44 mm) due to mitral stenosis (n = 8), mitral regurge (n = 5), arterial hypertension (n = 5) and multiple valvular disease (n = 3) fundamental multiplane TEE and transesophageal TDE were performed with standardized gain setting. The control group consisted of 20 randomized individuals with normal left

Preoperative two- and three-dimensional transesophageal echocardiographic assessment of heart tumors

BACKGROUND

Two-dimensional transesophageal echocardiography is the most widely used diagnostic approach in the rare entity of heart tumors. The aim of this study was to assess the diagnostic usefulness of three-dimensional echocardiography in comparison with the two-dimensional technique in a rare clinical setting.

METHODS

Twenty-seven patients (18 women; mean age, 49.7 +/- 14 years) with a histologically proven diagnosis of a cardiac tumor were studied. The primary diagnosis was done by a two-dimensional transthoracic echocardiography (n = 9) and transesophageal echocardiography (n = 18). In addition, we performed three-dimensional transesophageal assessment in 5 patients with left atrial myxomas. The echocardiographic findings were compared with the intraoperative appearance and pathologic diagnosis.

RESULTS

The echocardiographically suspected diagnosis of a heart tumor in 29 cases was histologically correct in 27 patients (myxomas, 20; epicardial lipoma, 1; malignant epicardial mesothelioma, 1; metastatic processes of hypernephromas, 2; and undifferentiated tumors of the pericardium, 3). Only the combination of multiplane transesophageal and three-dimensional echocardiography was able to demonstrate the shape, dimensions, location, origin, surface, three-dimensional movement, and involvement of valves and was most useful in the preoperative diagnosis and planning.

CONCLUSIONS

Three-dimensional transesophageal echocardiography yields important additional clinical information and improves the operative planning. Three-dimensional echocardiography may become the best approach to study the anatomy and pathology of the heart as it provides an objective display of cardiac size and shape in heart tumors.