Transesophageal echocardiography

Use of deep intravenous sedation with propofol and the laryngeal mask airway during transesophageal echocardiography

OBJECTIVE

To describe the use of either deep intravenous sedation with propofol or light sedation with midazolam and topical anesthesia during transesophageal echocardiography (TEE) and to report the incidence of respiratory complications and their management.

DESIGN

Retrospective study from March 2000 through August 2002.

SETTING

Single institution, specialized cancer center.

PARTICIPANTS

All patients undergoing TEE examination in the specified time period (n = 42).

MAIN RESULTS

Eight patients received light sedation and 34 patients received deep intravenous sedation with propofol. An airway event occurred in one patient in the light sedation group and in six patients in the deep sedation group. The patient in the light sedation group was managed with the use of a face-mask and a manual resuscitation bag. All airway events in the deep sedation group were managed successfully using the laryngeal mask airway (LMA).

CONCLUSION

Deep sedation with intravenous propofol can provide both excellent patient comfort and optimal conditions for TEE examination, particularly in patients who may require more lengthy procedures or in whom other techniques have failed. Although the incidence of respiratory depression was higher in patients receiving deep sedation with propofol than in patients who were lightly sedated (17.6% versus 12.5%, respectively), all six patients who had respiratory depression while under deep sedation with propofol were successfully ventilated using the LMA trade mark, without the need to remove the TEE probe and without terminating the examination prematurely. In contrast, in the one patient in the light sedation group who had respiratory depression, the TEE probe had to be removed to ventilate the patient via a face mask, and the procedure was cancelled.

Accurate assessment of mitral valve area in patients with mitral stenosis by three-dimensional echocardiography

The accuracy of measurements of mitral valve orifice area (MVA) from three-dimensional echocardiographic (3DE) image data sets obtained by a transthoracic or transesophageal rotational imaging probe was studied in 15 patients with native mitral stenosis. The smallest MVA was identified from a set of eight parallel short-axis cut planes of the mitral valve between the anulus and the tips of leaflets (paraplane echocardiography) and measured by planimetry. In addition, MVA was measured from the two-dimensional short-axis view (2DE). Values of MVA measured by 3DE and 2DE were compared with those calculated from Doppler pressure half-time (PHT) as a gold standard. Observer variabilities were studied for 3DE. MVA measured from PHT ranged between 0.55 and 3.19 cm2 (mean +/- SD 1.57 +/- 0.73 cm2), from 3DE between 0.83 and 3.23 cm2 (mean +/- SD 1.55 +/- 0.67 cm2), and from 2DE between 1.27 and 4.08 cm2 (mean +/- SD 1.9 +/- 0.7 cm2). The variability of intraobserver and interobserver measurements for 3DE measurements was not significantly different (p = 0.79 and p = 0.68, respectively); for interobserver variability, standard error of the estimate = 0.25. There was excellent correlation, close limits of agreement (mean difference +/- 2 SD), and nonsignificant differences between 3DE and PHT for MVA measurements (r = 0.98 [0.02 +/- 0.3] and p = 0.6), respectively. There was moderate correlation, wider limits of agreement, and significant difference between 2DE and PHT for MVA measurements (r = 0.89 [0.32 +/- 0.66] and p = 0.002), respectively. This may be related to the difficulties in visualization of the smallest orifice in precordial short-axis views. This study suggests that three-dimensional image data sets, by providing the possibility of "computer slicing" to generate equidistant parallel cross sections of the mitral valve independently from physically dictated ultrasonic windows, allow accurate and reproducible measurement of the MVA.

A study of spontaneous echo contrast in patients with rheumatic mitral stenosis and normal sinus rhythm: an Indian perspective

OBJECTIVE

To study the incidence of spontaneous echo contrast in left atrium of Indian patients with rheumatic mitral stenosis in normal sinus rhythm and to define its relations.

SUBJECTS

Transthoracic and multiplane transoesophageal echocardiographic studies were performed in 89 consecutive patients with rheumatic mitral stenosis who were in normal sinus rhythm.

RESULTS

Spontaneous echo contrast in the left atrium was seen in 57.3% of patients on multiplane transoesophageal echocardiography and in only 5.6% on transthoracic echocardiography. The mean mitral valve area was 1.07 (SD 0.33) cm2 and 1.32 (0.45) cm2 (P = 0.004), mean left atrial size was 4.27 (0.67) cm and 3.91 (0.5) cm (P = 0.029), mean diastolic pressure gradient was 12.64 (5.69) mm Hg and 10 (5.5) mm Hg (P = 0.049), and absence of mitral regurgitation was seen in 45% and 23% of patients respectively (P = 0.1). Among patients with spontaneous echo contrast, 31% had either left atrial/appendage thrombus or a history of embolism, upsilon 0% in patients without spontaneous echo contrast (P < 0.0001).

CONCLUSIONS

There is a high incidence of spontaneous echo contrast in the left atrium in Indian patients with rheumatic mitral stenosis in normal sinus rhythm on multiplane transoesophageal echocardiography. These patients are likely to embolise or form thrombi in the left atrium. The presence of spontaneous echo contrast is also associated with significantly smaller mitral valve area, larger left atrium, and higher mean diastolic mitral pressure gradient.

Morpho-functional assessment of interatrial septum: a transesophageal echocardiographic study

BACKGROUND

Despite the increasing number of reports on lipomatous hypertrophy of interatrial septum, a standardization of measurement of the dimensions of the interatrial septum (IAS) in the different phases of cardiac cycle has not been reported. Moreover, no data on modification of thickness with age and in specific cardiac diseases are available.

OBJECTIVE

Our purpose was to study whether the changes of thickness and thinning of IAS may be related to age, left atrial dimension, cardiac cycle and different cardiac diseases.

METHODS

248 patients (mean age 52.7 +/- 19.9 years) underwent transthoracic (TTE) and transesophageal (TEE) echocardiography. IAS was measured at the constant regions anterior and posterior to the fossa ovalis. IAS thickness (tk), thinning (th) and % thinning (% th) were measured.

RESULTS

IAS thickness ranged from 4 to 13 mm at the time of ventricular end-systolic phase (mean 6.7 +/- 1.9 mm) and from 6 to 16 mm at the time of atrial systole (mean 9.9 +/- 1.8 mm); significant statistical difference between these values was found (P < 0.01). IAS thinning ranged from 1 to 7 mm (mean 3.42 +/- 1.8) while % IAS thinning from 18 to 76% (mean 36.53 +/- 16.36%). Statistical analysis showed a significant positive correlation between age and ventricular end-systolic thickness and atrial systolic thickness and thinning. An insignificant correlation was found between age and % IAS thinning and between left atrial dimension and IAS tk and th.

CONCLUSIONS

Our results demonstrate that IAS thickness increases by age; no correlation exists between IAS thinning and age. There is no difference between IAS thickness and thinning in patients with or without cardiac disease. We believe that the thickness of IAS can be considered hypertrophic only if it exceeds the value of 15 mm during both ventricular end-systolic and atrial systolic phases of the cardiac cycle. IAS thickness and thinning might be an additional parameter to evaluate systolic atrial function particularly with regard to maintenance of synus rhythm after conversion from atrial fibrillation as well as to better understand its role in determining the filling of ventricles in different clinical conditions.

Reference values for normal adult transesophageal echocardiographic measurements

Normal transesophageal echocardiographic measurements have not been presented previously relative to the effects of age, sex, and body surface area. This comparison was obtained by measuring cardiac and aortic dimensions in 60 patients (20 to 75 years old; 33 women) with normal transesophageal echocardiograms. We found a variable and usually important relationship between body surface area and 11 of 20 structures measured. A gender effect was not significant after indexing for body surface area for all but one structure. Age correlated with the diameter of the aortic root, descending aorta, superior vena cava, and right pulmonary artery. Similar dimensions were noted for certain paired structures as the two atria, the mitral and tricuspid annuli, and the aortic root and right ventricular outflow tract. Although multiple factors underlie what is normal in a given individual, our reference values serve to facilitate recognition of cardiac and aortic disease.

Transesophageal echocardiography in pericardial disease and tamponade

While most pericardial disorders can be imaged by transthoracic echocardiography, transesophageal echocardiography may be required in those cases where pericardial pathology is clinically suspected, but cannot be imaged adequately with transthoracic echocardiography. Transesophageal echocardiography is especially helpful in patients after heart or chest surgery, with cardiac compression by a loculated pericardial hematoma, in patients with dissection, endocarditis, or interatrial shunting associated with pericardial effusion, in patients with pericardial tumors, and in the differential diagnosis between constrictive pericarditis and restrictive cardiomyopathy.

Assessment of viable myocardium by dobutamine transesophageal echocardiography and comparison with fluorine-18 fluorodeoxyglucose positron emission tomography

OBJECTIVES

The aim of this study was to assess whether dobutamine transesophageal echocardiography can identify viable myocardium in patients with chronic myocardial infarction.

BACKGROUND

Experimental and clinical studies have shown that dobutamine can recruit a contraction reserve in postischemic viable but akinetic segments, indicating that dobutamine-induced functional recovery is a potential ultrasound marker of myocardial viability.

METHODS

Forty patients underwent rest and dobutamine transesophageal echocardiography (dobutamine 5, 10 and 20 micrograms/kg body weight per min) and fluorine-18 (F-18) fluorodeoxyglucose positron emission tomography at rest. Three representative short-axis tomograms and a transverse four-chamber-view were used for wall motion and F-18 fluorodeoxyglucose-uptake analysis in corresponding myocardial regions. A basally asynergic segment was considered viable by transesophageal echocardiography if dobutamine-induced systolic wall motion could be observed. Viability by positron emission tomography was defined as F-18 fluorodeoxyglucose uptake > or = 50% of the maximal uptake in a region with normal wall motion by left ventriculography.

RESULTS

Functional recovery within the infarct region was found in 21 (53%) of 40 patients during dobutamine infusion. Infarct region-related viability by F-18 fluorodeoxyglucose uptake was diagnosed in 25 (63%) of 40 patients, yielding a diagnostic agreement between both techniques in 90% of patients. In 210 (89%) of 235 akinetic segments at rest, data on myocardial viability were concordant by the two techniques. The positive and negative predictive accuracy of dobutamine transesophageal echocardiography for viability defined by F-18 fluorodeoxyglucose uptake was 81% and 97%, respectively. Such uptake was significantly different (p < 0.001) between segments remaining akinetic (mean +/- SD 45 +/- 9%) during dobutamine infusion and segments with a dobutamine-induced contraction reserve (68 +/- 11%).

CONCLUSIONS

Dobutamine transesophageal echocardiography provides a promising low cost and widely available approach to unmask myocardial viability in patients with chronic myocardial infarction, and results compare favorably with those of F-18 fluorodeoxyglucose positron emission tomography.

Comparison of transthoracic and transesophageal echocardiography in the diagnosis of intracardiac tumors in adults

To compare transthoracic and transesophageal echocardiography in the diagnosis of intracardiac tumors, 17 patients (8 men and 9 women, aged 19 years to 67 years) whose intracardiac tumors were detected by echocardiography were studied in a 4-year period. Of these, 14 patients underwent cardiac surgery and 13 were proved to have tumors. There were 4 false-positive and 2 false-negative diagnoses by transthoracic echocardiography, but only one false-positive and no false-negative diagnosis by transesophageal echocardiography. The stalk of a myxoma was detected clearly in 5 of 11 patients by transthoracic echocardiography, whereas in 10 of 11 it was detected by transesophageal echocardiography. The detailed morphologic characteristics of the tumor, such as contour of the tumor, and the presence of cysts and calcification in the tumor, were seen more clearly with transesophageal echocardiography than with transthoracic echocardiography.

Ultrasonic dynamic three-dimensional visualization of the heart with a multiplane transesophageal imaging transducer

Dynamic three-dimensional echocardiography enables objective analysis of structures and pathologic conditions of complex geometry. In addition, it may provide more accurate quantitative analysis of cardiac function. This study presents the first results obtained with multiplane transesophageal diagnostic imaging system that is connected to a dedicated software configuration allowing three-dimensional tissue reconstruction and its dynamic display at 25 frames/sec. In addition, it permits "computer slicing" through the beating heart along arbitrary orientations and the display of synthetic cross sections along these orientations with excellent resolution and grey values (dynamic anyplane echocardiography). The advantage of a multiplane transesophageal imaging transducer is that the acquisition of cross sections for three-dimensional reconstruction becomes an integral part of a routine diagnostic transesophageal study and only requires an additional 7 to 10 minutes of examination time. This approach will help to develop three-dimensional echocardiography and synthetic anyplane echocardiography into a practical clinical tool offering diagnostic information similar to magnetic resonance imaging.

Role of early postoperative surface echocardiography in the pediatric cardiac intensive care unit

OBJECTIVE

To compare surface echocardiographic data with catheterization and surgical observation as a way of deciding on the need to reoperate to correct hemodynamically important sequelae following pediatric cardiac surgery; to determine the false-negative diagnosis rate of surface echocardiography.

DESIGN

Case series.

SETTING

Tertiary-care center, pediatric cardiac intensive care unit.

PATIENTS

All 39 patients who underwent reoperation because of hemodynamically significant anatomic sequelae following primary or elective secondary surgery in 1 calendar year.

INTERVENTIONS

None.

MEASUREMENTS

Two-dimensional and color Doppler ultrasound assessment of anatomy and physiology following cardiac surgery.

RESULTS

In 85 percent, surface echocardiography provided sufficient information for surgeons to reoperate on the same admission. Detection of important residual shunts or arterial stenoses and identification of anatomic causes of pulmonary undercirculation (or overcirculation) in palliated single ventricle are feasible.

CONCLUSION

Early postoperative surface echocardiography is a viable way to decide on the hemodynamic adequacy of cardiac surgery.

The frequency of acquisition and quality of images obtained by transesophageal echocardiography: a prospective study of 100 consecutive cases

Although transesophageal echocardiography is capable of generating detailed images of the heart and aorta, the quality of these images and the frequency of their acquisition has not been previously defined. We performed monoplane transesophageal echocardiograms in 100 consecutive patients to determine the quality and frequency of acquisition of 10 standard, transverse views of the heart and aorta. Each image was graded for quality by ascribing a value from 0 (poor quality or not obtained) to 3 (excellent quality). The effect of age on image acquisition and quality was determined for patients less than or equal to 60 years (n = 54) versus greater than 60 years old (n = 46). For the 10 image planes, the average image quality score and the frequency of image acquisition (%) was (1) 2.23 and 100% for the four-chamber view, (2) 1.96 and 98% for the right ventricular inflow view and coronary sinus, (3) 2.17 and 99% for the five-chamber view, (4) 1.80 and 84% for the aortic valve short axis, (5) 1.54 and 82% for the mitral valve short axis, (6) 1.84 and 91% for the mid-left ventricular short axis, (7) 1.02 and 59% for the left ventricular apical short axis, (8) 1.79 and 93% for the ascending aorta, (9) 1.23 and 77% for the aortic arch, and (10) 1.88 and 92% for the descending thoracic aorta view. Ascending aorta and aortic valve short-axis views were obtained with a significantly higher frequency in patients less than or equal to 60 years old.(ABSTRACT TRUNCATED AT 250 WORDS)

An audit of emergency echocardiography in a district general hospital

Eighty patients (43 M, 37 F), aged 23-89 years who were referred for emergency echocardiography over a 12-month period were prospectively studied in order to determine the reasons for emergency echocardiography and the influence of its results on patient management. The most frequent emergency request was to clarify whether the basis for cardiomegaly in a haemodynamically unstable patient was pericardial effusion or left ventricular dilatation. Other reasons for requests were for assessment for source of systemic emboli, acute complications of myocardial infarction, endocarditis, valve dysfunction and cardiac trauma. As a consequence of the emergency echocardiography, management was immediately influenced in 19 patients. This study has provided information on the specific settings in which emergency echocardiography can be justified.

Heart disease in patients with stroke: incidence, impact, and implications for rehabilitation. Part 1: Classification and prevalence

Heart disease is found in about 75% of patients who have suffered a stroke. Cardiovascular diseases can be risk factors, etiologic mechanisms, associated conditions, or direct consequences of stroke. Cardiac comorbidity may delay initiation of rehabilitation, complicate the course and care of the patient with stroke, inhibit participation in a therapeutic exercise program, limit functional outcomes, and contribute to early mortality in the individual with cerebrovascular disease. Part 1 of this two-part article describes the various forms of heart disease that may be seen in stroke patients, and reviews the incidence figures for each type of associated cardiac condition.

Transesophageal echocardiography as a tool in the evaluation of patients with embolic disorders

TEE has become one of the most powerful tools for evaluating patients with unexplained stroke, TIA, and peripheral and pulmonary embolization. This is especially encouraging in view of the previously disappointing results of TTE in these patients. In addition to the dramatic results in terms of clot visualization and the other intracardiac sources of embolization described previously, a new extracardiac source has been identified, namely protruding atheromas in the thoracic aorta. These atheromas have been seen for the first time because of the new diagnostic window that has been opened by the development of TEE. Their recognition and follow-up may lead to information that will change the approach to a significant number of patients with embolic ischemic episodes.

Diagnosis of right atrial mass lesions by transesophageal and transthoracic echocardiography

The echocardiographic findings by transesophageal and transthoracic techniques were compared in 16 patients with right atrial mass lesions diagnosed by transesophageal echocardiography. In only 8 of the 16 patients were the masses imaged by transthoracic echocardiography. Masses in the main body of the right atrium (three of five), as well as those associated with indwelling catheters and pacer wires (three of four) were more likely to be imaged by transthoracic echocardiography than masses in the right atrial appendage (zero of three) or in the superior or inferior vena cava (one of three). Associated masses in other cardiac chambers were detected by transthoracic echocardiography in three of six patients. Other features such as size, mobility, and site of attachment of right atrial masses in general were better defined by transesophageal echocardiography. Thus, patients with suspected right atrial masses should be investigated with transesophageal echocardiography.

Cardiovascular manifestations of Marfan's syndrome: improved evaluation by transoesophageal echocardiography

OBJECTIVES

To assess the value of transoesophageal echocardiography in patients with Marfan syndrome particularly those with suspected aortic pathology or where conventional transthoracic imaging was suboptimal.

DESIGN AND PATIENTS

Eleven patients with Marfan syndrome. Seven patients were studied because of suspected aortic dissection and four because of inadequate transthoracic imaging.

INTERVENTION

Transoesophageal echocardiography and colour Doppler flow mapping by a 5 MHz single plane transoesophageal probe.

RESULTS

Aortic dissection was identified in six patients with subsequent diagnostic confirmation in all six. No dissection was found in one patient in whom the diagnosis had been suspected clinically. Estimates of aortic root dimensions and assessment of aortic and mitral valve pathology were made in four other patients with inadequate transthoracic imaging.

CONCLUSIONS

Transoesophageal echocardiography provides rapid diagnostic information in patients with Marfan syndrome with suspected aortic dissection and enhances the assessment of cardiovascular manifestations of this condition.

Prospective study of blood culture during transesophageal echocardiography

To ascertain the incidence and significance of bacteremia associated with transesophageal echocardiography (TEE), 132 consecutive patients (aged 17 to 73 years) free of apparent infection who were undergoing 135 transesophageal echocardiographic procedures from October 1990 to August 1991, were prospectively studied. For each procedure, two sets of blood cultures were obtained for culture 30 to 60 minutes before TEE, immediately after, and 180 to 240 minutes after the procedure. For each blood culture, 10 ml of venous blood was evenly inoculated into aerobic and anaerobic culture bottles and inoculated for 7 days using a radiometric system. A throat swab was obtained immediately before each procedure. Three of 270 preprocedure blood cultures were positive for Bacillus cereus, Staphylococcus simulans, and Peptostreptococcus species, respectively. No blood culture was positive in the immediate postprocedure period. Two of 270 late blood samples grew Staphylococcus epidermidis in the same patient. Nevertheless, the microorganisms isolated from blood cultures were different from those isolated from the throat swab. No patients had fever or evidence of infective endocarditis after TEE during the follow-up period. It is concluded that the incidence of TEE-related bacteremia is extremely low, and a general recommendation for antibiotic prophylaxis during TEE is not warranted.

Transesophageal echocardiographic diagnosis of right-sided cardiac masses in patients with central lines

Transesophageal echocardiography provides excellent images of intracardiac masses; however, its use among a series of patients with central venous lines has not been fully described. Nineteen patients (aged 52 +/- 16 years; 10 women) had masses detected by transesophageal echocardiography in the presence of a permanent (0.2 to 16 years) pacing wire (n = 8), and a current (n = 9) or recent (n = 2) (1 to 281 days) indwelling catheter. Transthoracic echocardiography suggested the presence of a mass in 5 patients (26%), although in only 2 cases were its findings consistent with transesophageal findings. Transesophageal echocardiography indicated the presence of a mass in or near the superior vena cava in 13 patients, in the right atrium in 6, and adjacent to the tricuspid valve in 3. Discrete masses measured 1.6 +/- 2.1 cm2 in area during transesophageal echocardiography. Eleven patients had positive blood cultures, 7 with staphylococcal species. Mass size was not significantly altered by the type of line or sepsis, but showed a weak correlation with line age (r = 0.56). Transesophageal echocardiography altered the management of 9 patients, prompting surgery (n = 3) and line removal (n = 3), and antibiotic (n = 2) or anticoagulation (n = 3) therapy.

Anatomy, histology, and pathology of coronary arteries: a review relevant to new interventional and imaging techniques--Part IV

In the last 15 years, intense interest has focused on various interventional pharmacologic and mechanical forms of therapy for the treatment of atherosclerosis coronary artery disease. Many techniques and devices (dilating balloons, perfusion catheters, thermal probes and balloons, lasers, atherectomy devices, stents, intravascular ultrasound) have been used or are under study for future use. Many of these techniques and devices require an understanding of histologic and pathologic features of the coronary arteries and diseases which affect them. This article reviews selective areas of anatomy, histology, and pathology relevant to the use of various new interventional techniques. Part IV of this review will focus on congenital coronary artery anomalies, myocardial bridges, coronary aneurysm, emboli, and dissection and clinical implications regarding echocardiographic imaging techniques.

Multiplane transesophageal echocardiography: latest evolution in an imaging revolution

Multiplane imaging with a rotating phased-array transducer from within the esophagus represents the latest development in transesophageal cardiac ultrasound. Transverse, longitudinal, and all possible intermediate oblique planes are easily obtained from the same transducer with minimal probe manipulation. Three-dimensional conceptualization of complex structures and pathologic conditions is facilitated. The major advantages are a simplified examination procedure and much less patient discomfort than monoplane and biplane probe imaging.

Transesophageal dipyridamole echocardiography for diagnosis of coronary artery disease

The value of transthoracic dipyridamole echocardiography has been extensively documented. However, in some patients, because of a poor acoustic window, the rest transthoracic examination is not always feasible and the transesophageal approach is more convenient. Therefore, transesophageal echocardiography with high dose dipyridamole (up to 0.84 mg/kg body weight over 10 min) was performed in 32 patients in whom the transthoracic dipyridamole test either was not feasible (n = 29) or yielded ambiguous results (n = 3). The transesophageal echocardiographic test results were considered abnormal when new dipyridamole-induced regional wall motion abnormalities were observed. All 32 patients underwent coronary angiography; significant coronary artery disease was defined as greater than or equal to 70% lumen diameter narrowing in at least one major vessel. All patients also performed a bicycle exercise test 1 day before transesophageal dipyridamole echocardiography. Transesophageal stress studies were completed in all patients, with a maximal imaging time (in tests with a negative result) of 20 min. No side effects or intolerance to drug or transducer was observed. The left ventricle was always visualized in the four-chamber and transgastric short-axis views. High quality two-dimensional echocardiographic images were obtained in all patients both at rest and at peak dipyridamole infusion and were digitally analyzed in a quad-screen format. Coronary angiography showed coronary artery obstruction in 24 patients: 6 had single-, 9 double- and 9 triple-vessel disease. The transesophageal dipyridamole test showed a specificity of 100% and an overall sensitivity of 92%. The sensitivity of this test for single-, double- and triple-vessel disease was 67%, 100% and 100%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

The value of transesophageal echocardiography in the diagnosis of cardiac metastasis

To assess the diagnostic value of transesophageal two-dimensional echocardiography (TEE) as compared with transthoracic echocardiography (TTE), TTE and TEE were performed in eight consecutive patients (age range from 20 to 76 years, six male and two female) with clinical evidence of malignant tumors arising from the liver (n = 1), lung (n = 3), larynx (n = 1), osteogenic sarcoma (n = 1), lymphoma (n = 1), and yolk sac tumor in the anterior mediastinum (n = 1). In one case, the gastroscope could not be inserted because of tumor compression of the esophagus. Transesophageal echocardiography provided superior imaging in the detection of intracavitary metastatic lesions. In the case of right ventricular outflow tract tumor and greater vessel involvement, TTE may provide more imaging than TEE due to a blind area in this region by the transesophageal approach. In conclusion, TEE is complementary to TTE in the diagnosis of metastatic cardiac tumor.

Complications of transesophageal echocardiography in ambulatory adult patients: analysis of 1500 consecutive examinations

Transesophageal echocardiography is a new approach that can be used to image cardiac structures. It combines two existing technologies: cardiac ultrasound and endoscopy. To obtain a cardiac image, the transesophageal probe has to be positioned properly within the esophagus. The first 1500 consecutive transesophageal echocardiographic examinations in ambulatory adult patients from one center were analyzed to identify conditions associated with failed esophageal intubation and procedural complications. Esophageal intubation was not achieved in 11 patients (0.73%). The reasons for the failure of intubation were operator inexperience, hypersensitive pharynx despite topical anesthesia, and cervical spondylosis. Six of those patients also had a history of dysphagia. Procedural complications were identified in seven patients (0.47%). Tracheal intubation was present in four patients, with immediate development of stridor and incessant cough in two patients. Atrial fibrillation developed in two patients--one had atrial myxoma and one had mitral stenosis. Bronchospasm developed during the transesophageal examination in one patient who was receiving long-term treatment for bronchial asthma. We conclude that transesophageal echocardiography is feasible in most adult patients in the ambulatory setting and that the complication rate is very low. Proper patient selection and preparation are crucial to the successful performance of this procedure.

Panoramic transesophageal echocardiography. Clinical application of real-time, wide-angle, transesophageal two-dimensional echocardiography and color flow imaging

Panoramic transesophageal echocardiography is a new development in transesophageal echocardiography (TEE) technology, which yields a wide-angle imaging field for real-time two-dimensional and color flow imaging. We report our early experience in patients with the use of an annular-array TEE probe that provides a wide, 270 degrees angle imaging field for two-dimensional echocardiographic imaging. The field of view can, however, be narrowed to 15 degrees . The field of view for color flow imaging can be varied from 180 degrees to 10 degrees . Pulsed-Doppler recordings of flow velocity are also possible. This TEE system provides a panoramic vision of cardiac and paracardiac structures from the esophagus and stomach. Besides cardiovascular structures, other thoracic and upper abdominal organs can be visualized. The wide field of view allows a better comprehension of the cardiac anatomy and its relationship with adjacent structures. The initial experience suggests that this method, besides providing the usually required diagnostic information, may have a number of additional applications. Its clinical potential and directions for future developments are reviewed.

Spontaneous left atrial echocardiographic contrast in mitral stenosis: early disappearance after valve replacement

We describe a patient with mitral stenosis and severely enlarged left atrium. Transthoracic echocardiography showed a false image of intraatrial thrombus, whereas transesophageal echocardiography showed massive spontaneous left atrial contrast. Intraoperative transesophageal echocardiography was performed. During cardioplegic arrest the contrast was enhanced, but it gradually and completely cleared 15 minutes after cardiopulmonary by-pass arrest. Transesophageal echocardiography is a useful technique for the study of intraatrial masses and may bring a new dimension to tissue characterization studies.

Transesophageal echocardiography for congenital heart disease

Surface echocardiographic imaging of small children is routinely successful in defining anatomical details and Doppler flow patterns with even the most complex congenital cardiac malformations. However, in larger children or adults, imaging is frequently limited. A recent expansion of the role of echocardiography is intraoperative epicardial imaging. Epicardial and postoperative imaging, however, have significant limitations. To avoid some of these limitations, transesophageal echocardiography has increasingly been used in the arena of congenital heart disease. The more recent development of small sized gastroscopic probes has allowed transesophageal echocardiographic assessment of congenital heart disease in children down to newborn size. As detailed studies of individual lesions are reported, it has become clear that the mere presence of a congenital heart defect is not an indication for transesophageal echocardiography in most children if imaging can be accomplished by surface examination. However, transesophageal echocardiography may be indicated for the intraoperative or postoperative assessment of that defect, particularly when repair has been difficult or is known to be associated with significant residual abnormalities. Cardiac structures encountered with horizontal and vertical imaging plane transducers have been described and should be completely familiar to the examining echocardiographer.

Anomalous origin and course of coronary arteries in adults: identification and improved imaging utilizing transesophageal echocardiography

Anomalous origin of a coronary artery is rare, but may represent a clinically significant abnormality, since some anomalies are associated with myocardial ischemia, infarction, and sudden death. Diagnosis may elude routine screening procedures, and even when an anomalous vessel is identified angiographically, it may be difficult to delineate its true course on the basis of angiography alone. The purpose of this study was to determine whether transesophageal echocardiography (TEE) is of value in making the diagnosis and outlining the course of anomalous coronary arteries. Five adult patients with anomalous origin of a coronary artery were studied by monoplane TEE and selective coronary angiography. Transthoracic echocardiography (TTE) was also performed in four of these five patients. Anomalous coronary ostia were visualized in four of five patients utilizing TEE, but in none of four patients by TTE. A proximal segment of the anomalous coronary vessel was identified in all five patients by TEE, and in only two of four patients by TTE. TEE images were consistently of superior diagnostic quality. TEE is a valuable tool for the echocardiographic identification of anomalous coronary arteries, and is superior to TTE in adult patients.

Transesophageal echocardiographic evaluation of right atrial mass lesions

Transesophageal echocardiography with color flow Doppler studies was performed on 10 consecutive patients who had right atrial masses identified by transthoracic echocardiography. In one patient with right atrial myxoma, transesophageal study identified the tumor by its attachment to the atrial septum and ruled out the transthoracic finding of possible additional tumor mass in the right ventricle. In two instances the mass in the atria were deemed to be thrombi because of lack of attachment to the atrial septum, atrial fibrillation, and enlarged right atrial chambers. In all patients, the thrombi appeared larger by transesophageal study and was associated in one instance with atrial septal defect. The atrial septal defect was not identified by the transthoracic study and probably accounted for stroke of the patient through paradoxical emboli. In six patients, because of superior quality images rendered by transesophageal imaging, the right atrial mass lesions were deemed to be anatomic variants, which included prominent eustachian valves, remnants of Chiari network, and thickened atrial septum. We concluded that transesophageal echocardiography is superior to transthoracic imaging in elucidating the cause and significance of right atrial mass lesions and that it helps in guiding appropriate therapy.

Pericardial haemorrhage causing right atrial compression after cardiac surgery: role of transoesophageal echocardiography

After cardiac surgery transoesophageal echocardiography showed a large thrombus compressing the right atrium in three hypotensive patients. No satisfactory images were obtained by transthoracic imaging, which is often difficult in ventilated patients after cardiac surgery. Transoesophageal echocardiography, however, provided rapid diagnostic information and permitted prompt surgical intervention.

Improvement in the diagnosis of abscesses associated with endocarditis by transesophageal echocardiography

BACKGROUND

Echocardiography is recognized as the method of choice for the noninvasive detection of valvular vegetations in patients with infective endocarditis, with transesophageal echocardiography being more accurate than transthoracic echocardiography. The diagnosis of associated abscesses by transthoracic echocardiography is difficult or even impossible in many cases, however, and it is not known whether transesophageal echocardiography is any better.

METHODS

To determine the value of transesophageal echocardiography in the detection of abscesses associated with endocarditis, we studied prospectively by two-dimensional transthoracic and transesophageal echocardiography 118 consecutive patients with infective endocarditis of 137 native or prosthetic valves that was documented during surgery or at autopsy.

RESULTS

During surgery or at autopsy, 44 patients (37.3 percent) had a total of 46 definite regions of abscess. Abscesses were more frequent in aortic-valve endocarditis than in infections of other valves, and the infecting organism was more often staphylococcus (52.3 percent of cases) in patients with abscesses than in those without abscesses (16.2 percent). The hospital mortality rate was 22.7 percent in patients with abscesses, as compared with 13.5 percent in patients without abscesses. Whereas transthoracic echocardiography identified only 13 of the 46 areas of abscess, the transesophageal approach allowed the detection of 40 regions (P less than 0.001). Sensitivity and specificity for the detection of abscesses associated with endocarditis were 28.3 and 98.6 percent, respectively, for transthoracic echocardiography and 87.0 and 94.6 percent for transesophageal echocardiography; positive and negative predictive values were 92.9 and 68.9 percent, respectively, for the transthoracic approach and 90.9 and 92.1 percent for the transesophageal approach. Variation between observers was 3.4 percent for transthoracic and 4.2 percent for transesophageal echocardiography.

CONCLUSIONS

The data indicate that transesophageal echocardiography leads to a significant improvement in the diagnosis of abscesses associated with endocarditis. The technique facilitates the identification of patients with endocarditis who have an increased risk of death and permits earlier treatment.

Biplane transesophageal echocardiography: clinical applications of the long-axis plane

Tomography of the heart and great vessels is limited during conventional transesophageal echocardiography by the inability to rotate the transducer at the end of the transesophageal echocardiographic endoscope. A biplane transesophageal echocardiographic probe has been developed recently with a second transducer capable of long-axis imaging that yields long-axis views in addition to the familiar short-axis views. We describe our experience with 37 patients with a variety of cardiovascular diseases. In 17 patients new diagnostic information was obtained, although management was not changed. Long-axis scanning was particularly useful in the assessment of diseases of the thoracic aorta, valvular morphology and regurgitation, and congenital heart disease. Important limitations of the biplane imaging system include reduced image quality and a continued inability to rotate the transducer to obtain any desired plane of imaging. Nonetheless, biplane imaging enhances the versatility of transesophageal echocardiography and improves three-dimensional conceptualization of cardiac disease.

Safety of transesophageal echocardiography. A multicenter survey of 10,419 examinations

BACKGROUND

During the past few years, transesophageal echocardiography (TEE) has been increasingly used in clinical cardiology; data concerning the practicability and safety of the technique, however, are rare.

METHODS AND RESULTS

This report analyzes the experience of 15 European centers performing TEE studies for at least 1 year. At the time of this survey, 10,419 TEE examinations had been attempted or performed in these institutions. These TEE examinations were carried out by 54 physicians, 53.7% of whom had been trained in endoscopic techniques. Within the same time period, 160,431 precordial echocardiographic examinations were performed in the 15 institutions; the ratio between TEE and transthoracic studies averaged 9.03 +/- 6.4% (range of the 15 centers, 1.4-23.6%). Of the 10,419 patients, 9,240 (88.7%) were conscious inpatients or outpatients at the time of the TEE examination; the vast majority of the conscious patients did not receive intravenous sedation before TEE. In 201 cases (1.9%), insertion of the TEE probe was unsuccessfully attempted because of a lack of patient cooperation and/or operator experience (98.5%) or because of anatomical reasons (1.5%). In 90 of 10,218 TEE studies (0.88%) with successful probe insertion, the examination had to be interrupted because of the patient's intolerance of the echoscope (65 cases); because of pulmonary (eight cases), cardiac (eight cases), or bleeding complications (two cases); or for other reasons (seven cases). One of the bleeding complications resulted from a malignant lung tumor with esophageal infiltration and was fatal (mortality rate, 0.0098%).

CONCLUSIONS

This multicenter survey documents that TEE studies are associated with an acceptable low risk when used by experienced operators under proper safety conditions.

Diagnosis of noninfective cardiac mass lesions by two-dimensional echocardiography. Comparison of the transthoracic and transesophageal approaches

This study was conducted in 46 patients with cardiac thrombi, 15 patients with atrial myxomas, and 32 patients with other cardiac or paracardiac tumors. Diagnoses were subsequently proven by surgery, autopsy, computed tomography, magnetic resonance imaging, or angiography in all patients. All patients underwent precordial and transesophageal two-dimensional echocardiography to assess the various mass detection rates. Atrial myxomas and predominantly left-sided cardiac tumors were identified by both echocardiographic techniques with comparable detection rates. Left ventricular apical thrombi were detected more frequently by precordial echocardiography. In contrast, transesophageal echocardiography was superior in visualizing left atrial appendage thrombi, small and flat thrombi in the left atrial cavity, thrombi and tumors in the superior vena cava, and masses attached to the right heart and the descending thoracic aorta. These data indicate that transesophageal echocardiography leads to a clinically relevant improvement of the diagnostic potential in patients in whom cardiac masses are suspected or have to be excluded in order to ensure the safety of clinical procedures.

The clinical role of transoesophageal echocardiography

The role of transoesophageal echocardiography (TEE) was evaluated in a consecutive series of 100 procedures performed in 86 patients (age 17-81, mean 56 years). All patients had prior transthoracic echocardiography (TTE). TEE was performed with a 5 MHz phased array transoesophageal transducer with pulsed wave Doppler and colour flow mapping capability. Forty-four per cent of patients received intravenous sedation and 36% received antibiotic prophylaxis. There were no complications of TEE. The TTE and TEE findings were compared. In patients referred for possible cardiac source of embolism, left atrial thrombi were detected in 8/27 TEE studies but in none of 27 TTE studies. In 12 patients with prosthetic valve dysfunction TEE distinguished prosthetic from periprosthetic regurgitation in 9/12 studies compared to 3/12 with TTE. In 11 patients with suspected aortic dissection TEE correctly detected dissection in all seven cases in which the diagnosis was subsequently confirmed, whereas TTE showed only equivocal findings in two cases. Vegetations were detected by TEE in 4/5 studies in patients with proven native valve endocarditis and by TTE in 2/5. No vegetations were detected by TTE or TEE in five studies in patients with proven prosthetic valve endocarditis. Compared with other investigations there were no false positive TEE studies and one possible false negative study. We conclude that TEE is a safe procedure which often provides additional clinical information to transthoracic echocardiography.

Comparative value of transthoracic and transesophageal echocardiography in the assessment of congenital abnormalities of the atrioventricular junction

Information obtained from transthoracic and transesophageal echocardiography (two-dimensional echocardiography with spectral Doppler and color flow imaging) was compared in 17 patients with major congenital abnormalities of the atrioventricular (AV) junction (10 discordant AV connections, 1 criss-cross connection, 5 absent right connections and 1 absent left connection). The findings by either technique were correlated with findings at cardiac catheterization (12 patients) and at surgery (5 patients). In two of six patients with an absent AV connection as defined by transthoracic echocardiography, transesophageal imaging demonstrated an imperforate AV valve. In 11 of 11 patients with a discordant or criss-cross connection, assessment of AV valve and ventricular morphology (by defining the chordal attachments of both AV valves) was possible with transesophageal echocardiography (3 of 11 patients by transthoracic echocardiography); chordal straddling was detected in 1 patient and excluded in 3 others with an associated inlet ventricular septal defect. Anomalous pulmonary venous connection (one patient), atrial septal defect (three patients) and subpulmonary stenosis (five patients) were better assessed by transesophageal imaging, and atrial appendage morphology could be demonstrated in all. The transesophageal technique was less useful in demonstrating the anterior subaortic infundibulum or aortopulmonary shunt (two patients). Although systemic ventricular function could be assessed by either method with use of short-axis M-mode scans, transesophageal pulsed Doppler interrogation of AV valve and pulmonary venous flow patterns provided clues to diastolic dysfunction of the systemic ventricle.

Anatomic correlations of the long-axis views in biplane transesophageal echocardiography

The number of views obtainable during transesophageal echocardiography (TE) has been limited by the fixed position of the transducer at the end of the probe. This has confined standard TE studies to short-axis tomography of the heart and aorta. Recently, a biplane TE probe has become available that is capable of both long- and short-axis imaging. This study prospectively assessed the application of the long-axis plane of the biplane probe in providing complementary long-axis views in ambulatory patients. Six standard long-axis views could be obtained and were compared with corresponding anatomic sections to illustrate anatomic relations and facilitate structure identification. The long-axis views provide a better appreciation of the 3-dimensional nature of cardiac anatomy and function, especially in demonstrating the relation of vertically aligned structures.