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With this document, we update the recommendations for transoesophageal echocardiography (TOE) of the European Association of Cardiovascular Imaging. The document focusses on the areas of interventional TOE, in particular transcatheter aortic, mitral, and left atrial appendage interventions, as well as on the role of TOE in infective endocarditis, adult congenital heart disease, and aortic disease.

Transoesophageal echocardiography (TOE) is a standard and indispensable technique in clinical practice. The present recommendations represent an update and extension of the recommendations published in 2001 by the Working Group on Echocardiography of the European Society of Cardiology. New developments covered include technical advances such as 3D transoesophageal echo as well as developing applications such as transoesophageal echo in aortic valve repair and in valvular interventions, as well as a full section on perioperative TOE.

Multiplane transesophageal echocardiography (TEE) is a semi-invasive, very low-risk imaging procedure utilizing the upper gastric and esophageal echo windows to image the heart with the use of high-frequency transducers. It allows for high spatial resolution and access to structures that are routinely not well seen by transthoracic echocardiography, such as the left atrial appendage, the thoracic aorta, and the pulmonary veins, or where transthoracic imaging may be insufficient to answer a specific question, such as the presence of small vegetations, endocarditic abscesses, abnormalities of the interatrial septum, and others. Another important indication is the ventilated patient or the patient in the operating room, where transthoracic echocardiography is unrewarding or impossible. A particular role has emerged for TEE for identifying candidates for mitral valve repair by providing detailed functional and morphologic information on the diseased valve and by checking intraoperatively the results of surgery. A set of cross-sections, defined by anatomic landmarks, has been compiled, which can be systematically sought, evaluated, and modified according to the clinical question in order to extract the maximal information from TEE.

Aortic dissection is a life-threatening cardiovascular emergency requiring immediate diagnosis and treatment. It is mainly associated with hypertension and the Marfan syndrome. Diagnosis has been revolutionized by the use of transesophageal echocardiography (TEE), which allows for rapid and safe assessment of this condition. Echocardiographic hallmarks of aortic dissection ar the presence of a dissection membrane separating a true from a false lumen, rupture sites in the membrane with to-and-from flow, aortic regurgitation, and pericardial effusion. Dissection of the ascending aorta, which has an extremely high mortality and necessitates emergency surgery, is diagnosed quickly and accurately by TEE.

Transesophageal echocardiography (TEE) is now commonly used to evaluate the thoracic aorta, because it is widely available and provides high-resolution images and flow information by Doppler. This article reviews the essential features on TEE of acute and chronic aortic diseases, such as aortic dissection, aneurysm, and atherosclerosis, and discusses its strengths, weaknesses, and indications.

The shape and dynamics of the mitral annulus of 10 patients without heart disease (controls), 3 patients with dilated cardiomyopathy, and 5 patients with hypertrophic obstructive cardiomyopathy and normal systolic function were analyzed by transesophageal echocardiography and 3-dimensional reconstruction. Mitral annular orifice area, apico-basal motion of the annulus, and nonplanarity were calculated over time. Annular area was largest in end diastole and smallest in end systole. Mean areas were 11.8 +/- 2.5 cm(2) (controls), 15.2 +/- 4.2 cm(2) (dilated cardiomyopathy), and 10.2 +/- 2.4 cm(2) (hypertrophic cardiomyopathy) (P = not significant). After correction for body surface, annuli from patients with normal left ventricular function were smaller than annuli from patients with dilated cardiomyopathy (5.9 +/- 1.2 cm(2)/m(2) vs 7.7 +/- 1.0 cm(2)/m(2); P <.02). The change in area during the cardiac cycle showed significant differences: 23.8% +/- 5.1% (controls), 13.2% +/- 2.3% (dilated cardiomyopathy), and 32.4% +/- 7.6% (hypertrophic cardiomyopathy) (P <.001). Apico-basal motion was highest in controls, followed by those with hypertrophic obstructive and dilated cardiomyopathy (1.0 +/- 0.3 cm, 0.8 +/- 0.2 cm, 0.3 +/- 0.2 cm, respectively; P <.01). Visual inspection and Fourier analysis showed a consistent pattern of anteroseptal and posterolateral elevations of the annulus toward the left atrium. In conclusion, although area changes and apico-basal motion of the mitral annulus strongly depend on left ventricular systolic function, nonplanarity is a structural feature preserved throughout the cardiac cycle in all three groups.

The diagnosis of intramural hematoma by echocardiography classically requires the presence of an echolucent, crescentic region in the wall of the aorta. Recently we have encountered 2 patients in whom intramural hematoma was characterized only by thickening of the aortic wall, which was circumferential in one patient, thus making the diagnosis difficult to distinguish from common atherosclerotic thickening of the aorta. In one case, computed tomography showed more clearly the abnormal tissue signature of the intramural blood. In summary, absence of an echolucent zone does not exclude the diagnosis of intramural hematoma. Alternative imaging procedures such as computed tomography and magnetic resonance imaging may enhance the diagnostic accuracy.

Doppler evaluation of mitral regurgitation remains difficult; thus, a head-to-head comparison of the diagnostic accuracy of Doppler methods was undertaken. Fifty patients with native mitral regurgitation underwent multiplane transesophageal echocardiography within 5 days of catheterization. Angiographic grade of mitral regurgitation and, in 20 patients with grade II-IV regurgitation, invasively determined regurgitant stroke volume were compared with color Doppler area, regurgitant jet diameter, ratio of systolic to diastolic peak pulmonary venous flow velocities, and (based on the proximal convergence zone) maximal regurgitant flow rate and regurgitant orifice area. Rank correlation coefficients of angiographic grade with Doppler parameters were 0.61 for color jet area, -0.61 for pulmonary venous flow velocity ratio, 0.69 for color jet diameter, 0.79 for maximal regurgitant flow rate, and 0.78 for regurgitant orifice area (all P < .01). Convergence zone-based parameters also correlated best (r=0.73) with invasively determined regurgitant stroke volume. Receiver operating characteristic curve analysis confirmed higher diagnostic accuracy for proximal jet width and proximal convergence zone parameters than for color jet area or pulmonary venous flow velocity ratio. Proximal convergence zone parameters and proximal color jet diameter best distinguished severe from mild forms of mitral regurgitation.

Objectives: The aim of this study was to examine the value of dynamic three-dimensional (3D) transesophageal echocardiography (TEE) for the postoperative evaluation after extended myectomy and surgical reconstruction of the subvalvular mitral valve apparatus in patients with hypertrophic obstructive cardiomyopathy (HOCM)., Background: Two-dimensional imaging techniques such as echocardiography, computed tomography and magnetic resonance imaging have not been able to precisely quantify the effects of surgical therapy on the morphology of the left ventricular outflow tract (LVOT)., Methods: Multiplane TEE with 3D reconstruction was performed in 11 patients before and after the operation and in 16 normal control subjects for comparison. The preoperative maximal systolic pressure gradient in the LVOT was 69 +/- 59 mm Hg. The following variables were measured within the dynamic 3D data set: depth, width, length and cross-sectional area (CSA) gain caused by the myectomy trough, minimal CSA of the LVOT at each time point and its cyclic changes and maximal mitral leaflet deviation during systole., Results: Functional class improved from 3.0 +/- 0.2 before the operation to 1.5 +/- 0.6 after it. The maximal systolic pressure gradient in the outflow tract decreased to 26 +/- 21 mm Hg postoperatively (p < 0.001). Minimal CSA of the outflow tract increased from 1.1 +/- 1.2 to 3.8 +/- 1.9 cm2 postoperatively (p < 0.001), similar to the value of the control group (4.2 +/- 1.5 cm2, p = NS). The area gain due to the myectomy trough was 1.3 +/- 1.0 cm2, corresponding to 48 +/- 12% of the total operative area difference. Maximal systolic depth of the myectomy was 7 +/- 2 mm, maximal width was 20 +/- 8 mm and length was 28 +/- 7 mm. Maximal deviation of the mitral leaflets fell from 15 +/- 7 to 6 +/- 7 mm postoperatively (p < 0.01). In five patients mass measurements of the intracavitary portion of the papillary muscle (PM) revealed an increase from 7.3 +/- 1.0 to 12.1 +/- 2.5 g due to surgical mobilization of PMs (p < 0.01)., Conclusions: 3D TEE quantifies the differences in outflow tract morphology before and after surgery for HOCM. This technique may have an impact on the planning of operative interventions and allow for the evaluation of its results.

Background: A noninvasive method for the determination of size and spatial relationships of atrial septal defects to adjacent cardiac structures, which would be advantageous to those contemplating device closure, is described. The aim of the study was to examine the value of transesophageal three-dimensional echocardiography for this purpose., Methods and Results: Three-dimensional reconstruction of transesophageal two-dimensional echocardiography was performed in 17 patients. Left-to-right shunt (by oximetry in 16 of 17 patients) was 2.4 to 16.2 L/min, and the Qp/QS ratio was 1.4 to 4.7. The defect area of the atrial septal defect was measured throughout the whole cardiac cycle each 40 ms from the three-dimensional data set. Results were compared with shunt parameters by oximetry and with intraoperative measurements. Distances between atrial septal defect and mitral and tricuspid annulus and the orifices of the caval and pulmonary veins were also measured. The atrial septal defect area ranged from 0.2 to 2.4 cm2 (diastole) to 0.5 to 5.6 cm2 (systole). The maximal area at end-systole was 108% of the area at beginning of systole, and the minimal area at end-diastole was 43%. The defect area correlated significantly with the Qp/QS ratio (r=.70), and the maximal atrial septal defect diameters as measured by using three-dimensional echocardiography correlated well with intraoperative measurements (r=.87). Distances to mitral and tricuspid annulus and to the superior caval vein were determined in all patients. Distances to orifice of the inferior caval vein were measured in 12 patients, and orifices of right pulmonary veins were visible in 5 patients., Conclusions: Transesophageal three-dimensional echocardiography of atrial septal defects allows the determination of the instantaneous defect area and its dynamic changes and thus provides valuable information about the distances to adjacent cardiac structures. This may have clinical implications for the selection of patients suitable for interventional closure and for the assessment of procedural success.

To evaluate the additional value of transesophageal (TEE) compared with transthoracic (TTE) echocardiography and the role of patent foramen ovale (PFO) and deep vein thrombosis in the work-up of embolic events, patients with presumed cardiac embolic stroke or transient ischemic attack (neurovascular etiology was excluded) were prospectively studied by transthoracic and transesophageal contrast echocardiography. If PFO was detected echocardiographically, PFO size was assessed semiquantitatively and phlebography of both legs was performed. Two hundred forty-two consecutive patients (153 men, 60 +/- 15 years) were studied. In 197 patients, neuroimaging showed evidence of embolic infarction. TEE identified 138 potential cardiac sources of embolism in 111 patients, compared with 69 by TTE (p <0.01) in 59 patients. TEE detected potential cardiac sources in 52 patients with negative TTE examination and was significantly superior compared with TTE for identifying left atrial thrombi, spontaneous echo contrast, PFO, atrial septal aneurysm, and atheroma of the ascending aorta. In patients with a positive TTE, additional diagnostic information by TEE was found in only 6 patients and did not change therapy. Phlebography was performed in 53 patients with PFO and revealed deep vein thrombosis in 5 patients (9.5%); all had medium or large PFOs. Thus, in patients with cerebral ischemia of suspected cardiogenic origin and a normal TTE examination, TEE detects potential causes of embolism in 31% of patients and is therefore of diagnostic relevance. Conversely, in the presence of a diagnostic TTE an additional TEE confers only marginal diagnostic benefit. Deep venous thrombosis was detected in nearly 10% of patients with PFO as the sole identifiable cardiac risk factor. Given that in 4 of 5 patients deep vein thrombosis was clinically silent, phlebography should be performed in patients with medium or large interatrial shunts if paradoxical embolism is suspected.

Transoesophageal echocardiography has been performed in conjunction with pacing, dobutamine, or dipyridamole stress to detect stress-inducible ischaemia, and has proved to be a highly accurate diagnostic tool. Its advantages of improved image quality and high diagnostic accuracy have to be weighed against the disadvantages of semi-invasiveness and patient discomfort. The existing data on this stress echo modality and on special applications (diastolic dysfunction, ischaemic mitral regurgitation, hibernating myocardium, peri-operative risk assessment) are reviewed.

Unlabelled: In transesophageal echocardiography several methods have been used to grade mitral regurgitation. For a direct comparison of these techniques, 36 patients (60 +/- 13 years) with native mitral regurgitation underwent multiplane transesophageal echocardiography and angiography within 5 days. We compared the following measurements: 1) The maximal color jet area of mitral regurgitation, 2) the ratio of maximal systolic to diastolic pulmonary venous flow velocity in the left upper pulmonary vein, 3) the proximal jet width of mitral regurgitation, 4) the maximal regurgitant flow rate Qmax, measured by the proximal convergence method, 5) the regurgitant office area Areg, calculated by dividing Qmax by maximal regurgitant velocity obtained by continuous wave Doppler., Results: The correlation between color jet area (r = 0.4; p < 0.05) or pulmonary venous flow (r = -0.3; p = n.s.) with angiographic severity of mitral regurgitation is low. The sensitivity of the retrospective best cut-off values is 69% (color jet area) and 83% (pulmonary venous flow). Using retrospective best cut-off values all patients with mitral regurgitation Sellers grade III and IV are correctly identified by a proximal jet width > or = 0.7 cm, Qmax > or = 300 ml/s or a Areg > or = 0.5 cm2 (sensitivity and specificity of 83-100%). Spearman's rank coefficient demonstrated a high correlation (r = 0.75-0.77; p < 0.001) between proximal jet width, Qmax and Areg and with angiographic severity., Conclusion: Multiplane transesophageal echocardiographic grading of mitral regurgitation by proximal jet width or proximal convergence zone shows comparably good results and is clearly superior to grading by color jet area or pulmonary venous flow, if adequate image quality is achieved.

Elevated left ventricular mass and increased wall thickness have important prognostic implications in clinical medicine. However, these parameters have been incompletely characterized by one- and two-dimensional echocardiography. Therefore this study was performed to validate in vitro measurement of left ventricular mass and circumferential wall thickness with a multiplane transesophageal transducer and three-dimensional reconstruction. Results for mass measurements were also compared with a standard method for the determination of left ventricular mass, the Penn convention. Fourteen necropsied left ventricles were scanned in a water bath by a volume-rendering, three-dimensional reconstruction system. There was an excellent correlation and high agreement for determination of three-dimensional left ventricular mass (r = 0.98; standard error of the estimate [SEE] = 9.6 gm; y = 1.02x + 0.46) and wall thickness (r = 0.93; SEE = 1.4 mm; y = 0.95x + 1.64) compared with anatomic measurements. Left ventricular mass by a simulated Penn convention revealed a lower correlation and larger error compared with three-dimensional measurements (r = 0.72; SEE = 42.8 gm; y = 1.01x + 9.61). Therefore determination of left ventricular mass by three-dimensional reconstruction was validated in vitro and was superior to one-dimensional echocardiographic methods.

The case of a quadricuspid aortic valve diagnosed in adult age is reported. A 67-year-old patient, who had no previous diseases or cardiovascular complaints, presented in the clinic for an embolic occlusion of the left retinal artery. Isolated moderate aortic regurgitation was diagnosed clinically and echocardiographically. For its further evaluation and for seeking embolic sources, multiplane transesophageal echocardiography was performed, which discovered a quadricuspid aortic valve as the cause of aortic regurgitation and major atherosclerotic lesions in the ascending aorta and the aortic arch as possible cause of the embolic event. The fourth, accessory cusp, smaller than the other three, was localized between the non-coronary and left coronary cusp. In the short axis view the quadricuspid aortic valve showed in diastole a "X"-configuration, with a persistent central orifice between the commissures, which was the cause of the regurgitation jet in color Doppler examination, and in the systole a trapezoid opening pattern. In the long-axis view the valve showed a tricuspid closing pattern. The quadricuspid aortic valve can be exactly diagnosed by multiplane transesophageal echocardiography.

Background: Biplane angiographic and transthoracic echocardiographic volume calculations have shown to be sufficiently reliable in symmetric hearts; however, they are unreliable in the presence of aneurysmatic distortions. Multiplane transoesophageal echocardiography offers unobstructed cross-sectional views of the heart from one stable transducer position with the potential of imaging irregular cavity forms more accurately. It was the purpose of this in vitro study to compare the precision of multiplanar transoesophageal echocardiography to that of biplane angiography in determining left ventricular volumes, especially in aneurysmatic models., Methods: Seven silicon rubber models of the left ventricle from post-mortem specimens (four with aneurysms) were filled with 30 different volumes (range 153-256 ml, 197 +/- 30 ml). Echocardiographic cross-sections (20 degree rotational steps) were obtained from different transducer positions, utilizing a multiplanar probe with a central rotational axis. Volumes were calculated using the disc-summation method. For comparison the same volumes were determined by standard biplane angiography. The minimum number of echo cross-section necessary to optimize precision was analysed by calculating volumes for each increasing equidistant rotational step., Results: Linear correlation between measured volume using a multiplanar transoesophageal echoprobe and true volume was high (r = 0.97) and significantly better than for biplane angiography (r = 0.88; P < 0.001). Measurement bias and imprecision were also significantly lower with multiplanar echocardiography than with biplane angiography (3.9 +/- 7.1% vs 11.1 +/- 15.4%, and 2.0 +/- 3.7% vs 5.9 +/- 8.3%; P < 0.001). Precision of biplane angiographic volume measurements was significantly influenced by the presence of aneurysmatic distortions. Multiplanar echo volumes, however, were not influenced by left ventricular geometry and transducer positions. Nine echo cross-sections provided optimal precision., Conclusions: Three-dimensional echocardiographic volume calculations using a multiplanar transoesophageal echoprobe and the disc-summation method provide precise measurements unaffected by left ventricular geometry and transducer position in an in vitro setting. Standard biplane angiography is significantly less precise.

Graft failure or progressive native vessel disease can be a serious problem after coronary artery bypass grafting. However, because of poor image quality it may be difficult to evaluate these patients by transthoracic stress echocardiography. The purpose of this study, therefore, was to evaluate the effectiveness of dobutamine stress echocardiography in the detection of myocardial territories with compromised vascular supply (due to either an obstructed native vessel without graft, and obstructed graft, or a native vessel obstructed distal to bypass graft insertion with < or = 50% luminal diameter reduction on angiography) after coronary artery bypass grafting and to determine additional information obtained by biplane transoesophageal stress echocardiography. Sixty patients (54 men, mean age 59 +/- 8.5 years) who had undergone coronary bypass grafting (total number of graft vessels 198) were evaluated from 6 months to 14 years (mean 6.2 years) after surgery. Transthoracic dobutamine stress echocardiography, biplane transoesophageal dobutamine stress echo, and coronary angiography were performed and evaluated by independent examiners. An infusion of dobutamine up to a maximum of 40 micrograms.kg-1.min-1 was administered, and additional atropine (0.25-1.0 mg) was given if 85% of age-predicted maximal heart rate was not reached. Biplane transoesophageal echocardiography was performed in the transgastric short-axis view as well as transoesophageal 4- and 2-chamber views, allowing division of the left ventricle into a 14-segment scheme. Wall motion abnormalities induced with dobutamine stress were used to predict regional vascular insufficiency. A 4-point scale, ranging from 'excellent' (1) to 'impossible' (4) was used to assess each system's ability to evaluate all left ventricular segments. Forty-five patients, of whom 35 were identified by transthoracic echocardiography (sensitivity 78%), had at least one territory with a compromised vascular supply. In 15 patients, the vascular supply was uncompromised, with 13 showing no wall motion abnormalities inducible by transthoracic echocardiography (specificity 86%). However, biplane transoesophageal echocardiography had a higher sensitivity and specificity than transthoracic echocardiography in detecting compromised vascular supply, 93% and 93%, respectively. The former system correctly classified the vascular supplies in 113 of 120 vascular territories (94%), according to whether they were compromised or uncompromised. This was significantly more (P < 0.05) than by classification with transthoracic dobutamine echocardiography, by which system only 102 of the 120 vascular territories were correctly assessed (85%). Compared with the conventional transgastric monoplane short-axis view, examination using three different views via a biplane probe results in a higher sensitivity (93% vs 84%). Assessed on a 4-point scale, the ability to evaluate all left ventricular segments was 2.3 +/- 0.7 (mean +/- SD) for transthoracic echocardiography and 1.7 +/- 0.7 (P < 0.01) for biplane transoesophageal echocardiography. After coronary artery bypass grafting transthoracic dobutamine stress echocardiography has acceptable accuracy in the detection of regional vascular insufficiency. However, this accuracy can be improved using the higher image quality of transoesophageal echocardiography, combined with the advantages of several different views obtained by biplane transoesophageal echocardiography.

First experience with the dynamic three-dimensional reconstruction of transesophageal echocardiographic images in more than 100 patients with various cardiac diseases are reported. Ninety different two-dimensional image planes were acquired for each reconstruction using a conventional multiplanar transducer, connected to a stepper motor and controlled by a computer-based image acquisition system with special software. Acquisition time for one data set was 2.3 +/- 0.9 min, and calculation time to achieve three-dimensional images was 20-45 min. Several cardiac structures were reconstructed and analyzed qualitatively and quantitatively (measurements of distances and areas, volume calculation by Simpson's rule). Image sequences showing three-dimensional depth by gray scale modification were generated. After image acquisition one can select any desired cut plane to achieve perspectives that cannot be obtained by two-dimensional technique. Advantages of three-dimensional echocardiography are the display and potential quantification of pathomorphology of the left ventricle and mitral valve, atrial septal defects, intracardiac masses (i.e., myxomas, vegetations), and direct spatial imaging of complex congenital heart diseases. In principle, three-dimensional data sets have advantages for the quantitative evaluation of irregular formed cardiac structures, since the three-dimensional data set is more complete than cross-sections used in conventional two-dimensional echocardiography. Currently, however, these advantages are limited by the necessity of human interaction to segment the structures of interest.

In 41 patients with clinical evidence of active infective endocarditis, transesophageal echocardiography was performed in a stepwise manner, starting with evaluation of the monoplane views, followed by the longitudinal plane, and finally by the intermediate planes. Number, location, length, area, density, extent, and mobility of vegetations and abscesses were assessed in the monoplane, biplane, and best intermediate planes to identify and quantify the incremental value of the longitudinal and intermediate planes. Eighty-three vegetations and 6 abscesses were found. In 4 patients (10%) monoplane evaluation yielded false-negative results. There were no false-negative results using the biplane evaluation. However, when compared with multiplane evaluation, additional vegetations were missed in 23% of patients after monoplane and in 9% of patients after biplane evaluation. Three abscesses were missed using the monoplane and 1 was missed using the biplane technique. The area was underestimated in 60% of all vegetations (mean underestimation, 37% +/- 23% [SD] of maximal area) and length in 49% of cases (mean underestimation, 38% +/- 23% [SD] of maximal length) of all vegetations when biplane was compared with multiplane evaluation. Also, with monoplane and biplane evaluation, mobility and density were misinterpreted in 6% and 5% and 17% and 9% of all vegetations, respectively. Thus, multiplane transesophageal echocardiography is more accurate than the monoplane and biplane techniques in assessing patients with active infective endocarditis.

Unlabelled: To study the value of the newly introduced multiplane transesophageal transducer technology for the assessment of prosthetic valve regurgitation, 63 consecutive patients with 35 mitral and 33 aortic prostheses (23 bioprostheses and 45 mechanical prostheses) were examined. Transvalvular, paravalvular, and, in mechanical valves, normal or pathological transvalvular regurgitation were identified using first 0 degrees (transverse) and 90 degrees (longitudinal) planes combined with flexion of the echoscope tip and then additionally using multiple intermediary planes by transducer rotation. In a subgroup of 20 patients interobserver variability was evaluated. Both methods showed regurgitation in 56/58 valves; one additional case of regurgitation was seen by multiplane imaging only. However, there were 19 cases of regurgitation not clearly classifiable by biplane technique compared to only three using multiplane technique. Grading of severity was concordant by both modalities in 66 and discordant in only two cases. Observers disagreed on severity in 2/20 cases based on biplane imaging, but in none based on multiplane imaging; classification of regurgitation differed in 6/20 biplane and 1/20 multiplane images respectively., Conclusion: Multiplane transesophageal imaging improves classification of prosthetic regurgitation, but has little effect on severity grading.

Transesophageal stress echocardiography has been reported to have a high sensitivity and specificity for noninvasive identification and assessment of coronary artery disease. Its advantage is the virtually never obstructed acoustic window on the heart yielding superior image quality in almost all patients. Pharmacological stress as well as simultaneous atrial pacing--attaching electrodes to the echoscope--have been applied as stress modalities. Both transesophageal stress echocardiography modalities have been shown to be well tolerated, safe, and feasible in most patients. These promising initial experiences led to clinical application of this method for preoperative risk evaluation, for detection of restenosis after PTCA, and for evaluation of hibernating myocardium. This technique was also successful for evaluation of stress induced changes of transmitral and pulmonary venous flow in patients with left ventricular hypertrophy and coronary artery disease. Although all studies published so far were performed with monoplane technique, the sensitivity for detection of one-vessel and, even more so, multivessel disease was high. However, apical and basal wall-motion abnormalities may go undetected using monoplane equipment. The advent of biplane transesophageal imaging enables the visualization of more ventricular segments. Future studies will show to which degree biplane transesophageal stress echocardiography improves the diagnostic accuracy.

Although tomographic imaging has been very successful in cardiology,the quantitation of volumes, surfaces, and masses,as well as understanding of complex morphologies would improve by three-dimensional imaging. This review focuses on approaches to 3-D reconstruction from transesophageal echocardiography. In the past, several attempts using either stepwise parallel translation or stepwise rotation of the transducer have been made. In vitro and, to a limited extent, in vivo studies have confirmed high accuracy in calculating left ventricular volumes in such manner. Complex cardiac structures and their motion, such as the mitral annulus, mitral leaflets, atrial septal defects, and others have been reconstructed from patient studies. Although potentially a powerful tool for cardiac imaging with promising quantitation capabilities, progress is needed in particular in the field of border detection to make 3-D imaging practical enough for clinical use.

Assessment of prosthetic valve regurgitation by echocardiography remains difficult. To study the value of the newly introduced multiplane transesophageal technology for this purpose, prosthetic valve regurgitation was examined in 63 consecutive patients with 35 mitral and 33 aortic prostheses (23 bioprostheses and 45 mechanical prostheses). Transvalvular, paravalvular and, in mechanical valves, normal or pathologic transvalvular regurgitation were identified first with 0 degrees (transverse) and 90 degrees (longitudinal) planes combined with flexion of the echoscope tip and then additionally with multiple intermediary planes by transducer rotation. In a subgroup of 20 patients interobserver variability was evaluated. Both methods showed regurgitation in 56 of 68 valves; one additional case of regurgitation was seen by multiplane imaging only. However, 19 cases of regurgitation were not clearly classifiable by biplane transesophageal echocardiography compared with only three with multiplane transesophageal echocardiography. Grading of severity was concordant by both modalities in 66 and discordant in only two cases. Observers disagreed on severity in two of 20 cases based on biplane imaging but in none based on multiplane imaging; classification of regurgitation differed in six of 20 (biplane) and one of 20 (multiplane), respectively. Multiplane transesophageal imaging improves classification of prosthetic regurgitation but has little effect on severity grading.

The prevalence of a patent foramen ovale was assessed by simultaneously performing transesophageal contrast echocardiography and transcranial contrast Doppler sonography (TCD) in 137 subjects (mean age 36 years) with stroke of unclarified etiology (n = 41), clarified etiology (n = 33), and in normal subjects (n = 63; mean age 32 years). Patent foramen ovale was found significantly more often in patients with unclarified than clarified strokes or in normal subjects (66% vs 33%, or 43%). Massive paradoxical embolism through a patent foramen ovale, identified by TCD, occurred significantly (p < 0.01) more often in patients with unclarified (64%) than clarified (27%) strokes or in normal subjects (3%). However, minimal shunts were typical in normal subjects (79%). Patent foramen ovale was detected indirectly by TCD when calculated on the basis of transesophageal contrast echocardiographic findings (sensitivity 89%, specificity 92%). Thus, TCD reliably detects paradoxical cerebral embolism through a patent foramen ovale, and provides important additional information for evaluating its clinical relevance by semi-quantification of embolic contrast material.

Non-invasive documentation of restenosis after successful percutaneous transluminal coronary angioplasty (PTCA) remains a problem. Thus, transoesophageal pacing echocardiography (TPE) with simultaneous rapid atrial pacing via the same probe, a recently validated method for detection of coronary artery disease, was used in 60 patients for detection of restenosis after successful PTCA (54 patients with one and six patients with multivessel PTCA). The patients came for routine follow-up angiography 5.4 +/- 3.7 months after PTCA regardless of clinical status. Restenosis (diameter stenosis > or = 50%) was demonstrated in 22 patients. Disease progression in previously normal vessels was noted in three additional patients. Results for detection of restenosis and disease progression were compared to exercise ECG and in 40 patients to Tc-99m methoxy-isobutyl-isonitrile (MIBI)-radionuclide perfusion imaging. Diagnostic standard exercise ECG could be performed in only 38 patients, due to peripheral vascular disease, joint disease or premature exhaustion in the rest of patients. TPE was non-diagnostic in two patients due to ineffective pacing or patient discomfort. Sensitivity of TPE for detection of restenosis and disease progression after PTCA was 84% compared with 50% and 86% for exercise ECG and Tc-99m MIBI-SPECT (P < 0.03 and ns), respectively. Specificity of TPE (85%) was also higher than that of exercise ECG (59%, P < 0.03) and comparable to the specificity of MIBI-SPECT (84%). Overall accuracy of TPE was far superior to exercise ECG and similar to MIBI-SPECT (84% vs 54% and 85%) (P = 0.0007 and ns, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Multiplane transesophageal echocardiography is a new development in transducer technology, which allows by rotation of the transducer to obtain not only transverse and longitudinal planes but also all intermediate planes. Exterior control allows continuous rotation of the scanning plane from the conventional transverse plane, corresponding to 0 degree, to the longitudinal plane, corresponding to 90 degrees and further to a left-right inverted transverse plane, corresponding to 180 degrees. Although the echoscope tip, which houses the rotatable transducer, is slightly larger than conventional probes, in our clinical experience of well over 400 cases, intubation of the esophagus is not more difficult than with the mono- or biplane probe. In comparison with the biplane technique the adjustment of intermediate planes is easier and less unpleasant for the patient, since mechanical irritation due to sideward flexion of the probe is less often necessary. Plane rotation, effected by control buttons in the echoscope handle, takes eight seconds from 0 degree to 180 degrees. The probe incorporates a 5 MHz phased array transducer, which alternatively works at 3.7 MHz. Pulsed, continuous and color Doppler are also integrated. Multiplane transesophageal echocardiography was used to investigate several clinical questions. In 41 patients with aortic valve stenosis the valve area was determined by planimetry. The valve area was measured in an individually aligned short axis view (between 50 degrees and 70 degrees). A high correlation (r = 0.95; Y = 0.9 X + 0.1; p < 0.01) with invasively determined valve areas by the Gorlin formula was found.(ABSTRACT TRUNCATED AT 250 WORDS)