Is Transesophageal Echocardiography Necessary before D.C. Cardioversion in Patients with a Normal Transthoracic Echocardiogram?

PURPOSE: Transesophageal echocardiography has emerged as an accepted approach before D.C. cardioversion for atrial fibrillation. The frequency of atrial thrombi detected on transesophageal echocardiography has varied from 7% to 23%. Many patients undergoing transesophageal echocardiography have had a previous transthoracic echocardiogram. Though transthoracic echocardiography has a low yield for the detection of intracardiac thrombi, it is highly accurate in diagnosing a structurally abnormal heart. The purpose of this study was to assess the frequency of thrombi detected by transesophageal echocardiography in patients with an entirely normal transthoracic echocardiogram and hence the advocacy of a selective approach in performing transesophageal echocardiography in patients undergoing D.C. cardioversion for atrial fibrillation. METHODS: 112 consecutive patients with atrial fibrillation who had undergone transesophageal echocardiography before D.C. cardioversion were evaluated. They all had a transthoracic echocardiogram within the 2 months preceding their transesophageal echocardiogram. Based on their transthoracic echocardiographic study, they were divided into two groups: Group 1 consisted of patients with a normal transthoracic echocardiogram and Group 2, those with an abnormal study. RESULTS: Thrombi or spontaneous echo contrast were found in 14 of 112 patients (16%). All however were detected in Group 2 patients. There was no patient with a normal transthoracic echocardiogram who had thrombus on his/her transesophageal echocardiogram. CONCLUSIONS: Our results suggest that a selective approach may be exercised in the use of transesophageal echocardiography prior to D.C. cardioversion for atrial fibrillation. Patients with an entirely "normal" transthoracic echocardiogram may proceed directly to cardioversion without a precardioversion transesophageal echocardiogram.     

The value of transesophageal echocardiography in predicting immediate and long-term outcome of balloon mitral valvuloplasty: comparison with transthoracic echocardiography

The purpose of this study was to assess the role of transesophageal echocardiography in predicting the immediate and long-term outcome of balloon mitral valvuloplasty, and compare the results to transthoracic echocardiography. BACKGROUND: Transesophageal echocardiography accurately detects left atrial thrombi and allows better visualization of mitral valve morphology; however, its value in predicting the immediate and long-term outcome of balloon mitral valvuloplasty had not been assessed as adequately as for transthoracic echocardiography. METHODS: In 56 patients referred for balloon mitral valvuloplasty, both transesophageal and transthoracic echocardiography were performed (Group A). An echo score for both techniques was used to reflect mitral valve morphology, and its predictive value for immediate and long-term outcome of the valvuloplasty was assessed. The impact of transesophageal echocardiography in preventing procedural embolic events in those 56 patients was assessed by comparison to another group of 41 patients, who were examined only by transthoracic echocardiography prior to balloon mitral valvuloplasty (Group B). RESULTS: In Group A, transesophageal echocardiography detected left atrial thrombus in seven, while transthoracic echocardiography detected left atrial thrombus in two patients. After 2 months of warfarin therapy, a repeat transesophageal echo examination in four patients showed resolution of thrombus in three who went on to have balloon mitral valvuloplasty. Among the 52 patients who eventually had the procedure after thrombus was excluded by transesophageal echocardiography, there were no embolic events, compared to three embolic events among the 41 patients in Group B (P = 0.08). The transthoracic echocardiography scores, while slightly higher, correlated well with transesophageal echocardiography scores (r = 0.51, P < 0.001). The increase in mitral valve area did not correlate well to total transthoracic or transesophageal echocardiography scores, while it correlated negatively to valve calcification by transthoracic (r = -0.29, P < 0.05) and mobility by transesophageal echocardiography (r = -0.59, P < 0.02). At follow-up (7 +/- 4 months) nonsurvivors (7/56) had higher total scores by either transthoracic (P < 0.01) or transesophageal echocardiography (P < 0.05) compared to survivors. The percent reduction in mitral valve area was greater with age (r = 0.5, P < 0.02), time to follow-up (r = 0.67, P < 0.002), valve mobility by transthoracic echocardiography (r = 0.59, P < 0.01), and valve calcification by transthoracic echocardiography (r = 0.37, P = 0.09) and transesophageal echocardiography (r = 0.4, P = 0.07). CONCLUSIONS: Transesophageal echocardiography is superior to transthoracic echocardiography in detecting left atrial thrombi, and it may reduce the risk of embolic events following balloon mitral valvuloplasty. Assessment of mitral valve morphology by transesophageal echocardiography is complementary and not superior to assessment by transthoracic echocardiography. Mitral valve calcification and mobility appear to be the best morphological predictors of immediate and long-term outcome following balloon mitral valvuloplasty.     

The role of transesophageal echocardiography in the detection of left atrial thrombi

Sensitivity of transthoracic echocardiography in the detection of left atrial thrombi, in particular thrombi confined to the left atrial appendage, is surprisingly low (33%-72%). Concerning the detection of left atrial thrombi, transthoracic echocardiography appears as an inadequate technique in patients with suspected cardiogenic embolism with a success rate of only 0.8% in earlier, and about 3% in recent studies. Imaging from the esophagus substantially increases the detection rate for left atrial thrombi, and is the only clinically relevant semiinvasive technique to diagnose thrombi confined to the left atrial appendage. Transesophageal echocardiography has markedly increased the diagnostic power of cardiovascular ultrasound in patients with suspected cardiogenic embolism and/or atrial fibrillation. Meta-analysis of pooled studies using the transesophageal approach in these patients revealed thrombi within the left atrial cavity in about 7% and within the atrial appendage in about 12% of cases.     

Transesophageal echocardiography to detect atrial clots in candidates for percutaneous transseptal mitral balloon valvuloplasty

Left atrial thrombi are common in patients with mitral stenosis. When percutaneous balloon mitral valvuloplasty is performed on such patients, there is a potential risk of thrombus dislodgment and embolization. In this study conventional transthoracic echocardiography and transesophageal echocardiography were performed for percutaneous balloon mitral valvuloplasty on 19 consecutive candidates (6 men, 13 women, 23 to 81 years old). In five patients (26%), transesophageal echocardiography revealed a left atrial thrombus; in only one of these was there a suspicion of left atrial thrombus on transthoracic echocardiography. Balloon mitral valvuloplasty was canceled in four of the five patients. Three underwent mitral valve surgery that confirmed the echocardiographic findings. Transesophageal echocardiography is better than conventional transthoracic echocardiography in detecting left atrial clots in candidates for balloon mitral valvuloplasty. Because of the potential risk of embolization, transesophageal echocardiography is recommended in all candidates for balloon mitral valvuloplasty.     

Transthoracic echocardiography versus transesophageal echocardiography in detecting cardiac sources of embolism

Although the yield of potential cardiac sources of embolism by echocardiography in patients with stroke and arterial embolism has been low, with the advent of transesophageal echocardiography, a renewed enthusiasm for echocardiography in these patients has developed. This article reviews the six major studies comparing transthoracic to transesophageal echocardiography in the search for potential cardiac sources of embolism. The overall yield of transesophageal echocardiography in these studies for potential cardiac sources of embolism is 43% compared to 14% by transthoracic echocardiography in a total of 367 patients. In patients without clinical cardiac disease, the yield is lower but still substantially higher by transesophageal echocardiography (24% compared to 7% by transthoracic echocardiography). For left atrial thrombus, left atrial spontaneous contrast, patent foreman ovale, and atrial septal aneurysm (ASA), transesophageal echocardiography is clearly superior than transthoracic echocardiography. Data on the detection of mitral valve prolapse and left ventricular thrombus are conflicting and neither method is clearly superior. In addition, transesophageal echocardiography identifies certain abnormalities including debris in the aorta and prosthetic strands that transthoracic echocardiography is incapable of identifying. Although transthoracic echocardiography should continue to be the initial screening modality for stroke patients, transesophageal echocardiography should be performed when surface findings are negative or equivocal in patients with likely cardioembolic stroke.     

Right atrial compression in postoperative cardiac patients: detection by transesophageal echocardiography

Four patients developed hypotension after heart surgery. Hemodynamic measurements revealed elevated right atrial pressure with normal pulmonary capillary wedge pressure. Conventional transthoracic two-dimensional echocardiography was technically suboptimal for detection of pericardial effusion. In each patient transesophageal echocardiography demonstrated significant compression of the right atrium by a localized mass. At reoperation atrial compression by an organized hematoma was found and in each instance successfully drained. Thus, transesophageal echocardiography is superior to transthoracic echocardiography in evaluating critically ill postoperative hypotensive patients and can differentiate isolated right atrial tamponade from other causes of hemodynamic deterioration such as prosthetic valve dysfunction or left ventricular systolic dysfunction, or both.     

Transesophageal echocardiographic diagnosis of ventricular noncompaction associated with an atrial septal aneurysm in a patient with dilated cardiomyopathy of unknown etiology

The present report discusses a case of noncompaction of the ventricular myocardium in a 51-year-old woman with dilated cardiomyopathy of unknown etiology. Multiple transthoracic echocardiography examinations had failed to show myocardial noncompaction, but subsequently performed transesophageal echocardiography clearly demonstrated the characteristic findings of this unusual disease. Also, an atrial septal aneurysm was identified by transesophageal echocardiography. Patients with cardiomyopathy of unknown origin should be investigated to define the presence or absence of myocardial noncompaction, even if transthoracic echocardiography fails to show anatomical features of this disease. The present case is the first reported case of ventricular noncompaction associated with an atrial septal aneurysm as a congenital anomaly.     

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.     

Location, size and morphological characteristics of left atrial thrombi as assessed by echocardiography in patients with rheumatic mitral valve disease.

AIMS: This study aimed to assess the use of transthoracic and transoesophageal echocardiography in diagnosing the thrombi located in the left atrium and/or left atrial appendage in patients with rheumatic mitral valve disease, and to investigate the characteristics of thrombi in comparison to intraoperative findings. METHODS AND RESULTS: The study group was comprised of 474 patients who underwent transthoracic and transoesophageal echocardiography prior to mitral valve surgery. Location, thickness and morphological characteristics of thrombi were determined by transoesophageal echocardiography. Intraoperative assessment disclosed left atrial thrombi in 105 patients. Thickness of thrombi < or = 1cm, and thrombi confined to left atrial appendage were associated with false-negative results by transthoracic echocardiography. However, diameter and morphological characteristics of thrombi, left atrial and left atrial appendage size, and the presence of the spontaneous echo contrast were not associated with the diagnosis of thrombi by transthoracic echocardiography. For overall left atrial thrombi, sensitivity and specificity of transthoracic echocardiography were 32%, and 94%, respectively. Sensitivity and specificity of transoesophageal echocardiography for thrombi in the left atrial appendage were 98%, and 98%, for thrombi in the main left atrial cavity were 81%, and 99%, and for thrombi located in both left atrium and appendage cavities were 100%, and 100%, respectively. CONCLUSION: In patients with rheumatic mitral valve disease, detection of left atrial thrombi by transthoracic echocardiography seems to be determined by thickness and location of thrombi. The multilobed structure of the left atrial appendage and artifacts over posterior wall of the left atrium may still prevent precise diagnosis even with transoesophageal echocardiography.     

The utility of transesophageal echocardiography during and after Fontan operations in small children

Transesophageal echocardiography with Doppler examination was performed intraoperatively in 19 children undergoing modified Fontan operations and in 10 patients postoperatively. Comparisons were made with results of intraoperative epicardial imaging (9 patients) and with postoperative transthoracic imaging (10 patients). Transesophageal echocardiography optimally visualized atriopulmonary and cavopulmonary anastomoses. Epicardial echocardiography was successful in only three of nine patients. Intraoperative transesophageal echocardiography showed residua in 8 of 19 studies and led directly to surgical revision or medical therapy. These residua included stenosis of the cavopulmonary anastomosis (1 patient), unsatisfactory atrial fenestration (2 patients), patent ductus arteriosus (1 patient), residual cavoatrial shunting (1 patient), atrial thrombi (1 patient), and poor ventricular function (2 patients). Results of examination in the postoperative intensive care unit showed significant abnormalities in 4 of 10 patients. This study demonstrates that transesophageal echocardiography provides unique anatomic and physiologic information during and after modified Fontan operations in small children and therefore may have significant impact on patient management.     

Evaluation of pulmonary venous flow by transesophageal echocardiography in subjects with a normal heart: comparison with transthoracic echocardiography

Nineteen normal subjects and five patients with atrial fibrillation underwent transesophageal and transthoracic echocardiographic studies to evaluate the normal pulmonary venous flow pattern, compare right and left pulmonary venous flow and assess the effect of sample volume location on pulmonary venous flow velocities. Best quality tracings were obtained by transesophageal echocardiography. Anterograde flow during systole and diastole was observed in all patients by both techniques. Reversed flow during atrial contraction was observed with transesophageal echocardiography in 18 of the 19 subjects in normal sinus rhythm, but in only 7 subjects with transthoracic echocardiography. Two forward peaks during ventricular systole were clearly identified in 14 subjects (73%) with transesophageal echocardiography, but in none with the transthoracic technique. The early systolic wave immediately followed the reversed flow during atrial contraction and was strongly related to the timing of atrial contraction (r = 0.78; p less than 0.001), but not to the timing of ventricular contraction, and appeared to be secondary to atrial relaxation. Conversely, the late systolic wave was temporally related to ventricular ejection (r = 0.66; p less than 0.001), peaking 100 ms before the end of the aortic valve closure and was unrelated to atrial contraction time. Quantitatively, significantly higher peak systolic flow velocities were obtained in the left upper pulmonary vein compared with the right upper pulmonary vein (60 +/- 17 vs. 52 +/- 15 cm/s; p less than 0.05) and by transesophageal echocardiography compared with transthoracic studies (60 +/- 17 vs. 50 +/- 14 cm/s; p less than 0.05). Increasing depth of interrogation beyond 1 cm from the vein orifice resulted in a significant decrease in the number of interpretable tracings.(ABSTRACT TRUNCATED AT 250 WORDS)     

Transesophageal echocardiography is superior to transthoracic echocardiography in the diagnosis of sinus venosus atrial septal defect

The purpose of this study was to compare transthoracic and transesophageal echocardiography in the diagnosis of various types of atrial septal defects. Forty-one adult patients with the clinical diagnosis of atrial septal defect were studied by transthoracic and transesophageal echocardiography (30 women, 11 men; 18 to 81 years of age). Transthoracic echocardiography demonstrated the atrial septal defect in 33 patients (secundum type in 28, primum type in 3 and sinus venosus type in 2). Transesophageal echocardiography demonstrated the defect in all 41 patients. Thus, in 8 (20%) of 41 patients the atrial septal defect was demonstrated by transesophageal and not by transthoracic echocardiography. Six of the eight had a sinus venosus type atrial septal defect; the other two patients had a secundum atrial septal defect (one of these two had a technically poor transthoracic echocardiogram and the other had a small atrial septal defect). Transthoracic echocardiography, therefore, failed to demonstrate the sinus venosus defect in six (75%) of eight patients. An anomalous venous connection associated with the sinus venosus defect was visualized by transesophageal echocardiography in seven of the eight patients but was not seen on transthoracic echocardiography in any patient. Sinus venosus type atrial septal defects are frequently not visualized in adults by conventional transthoracic echocardiography. Transesophageal echocardiography is recommended when an atrial septal defect is clinically suspected but cannot be visualized by 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.     

Comparison of transthoracic and transesophageal assessment of prosthetic valve dysfunction

Transesophageal echocardiography has added another dimension to the assessment of prosthetic valve dysfunction with high-resolution images that allow for more detailed structural evaluation of tissue and mechanical valves. This study is a retrospective analysis of 140 prosthetic valves (90 tissue, 50 mechanical) in the mitral (89), aortic (45), and tricuspid (6) position in 116 patients studied by transthoracic and transesophageal echocardiography techniques. Transesophageal echocardiography was consistently better than the transthoracic technique in the evaluation of structural abnormalities of tissue valves in the mitral and aortic positions with respect to leaflet thickening, prolapse, flail, and vegetations. With transesophageal echocardiography, five tissue mitral valves had flail leaflets that were not identified by the transthoracic technique. Transesophageal echocardiography was better than transthoracic in the detection, quantification, and localization of prosthetic mitral regurgitation. Physiological mitral regurgitation was detected in 31 valves by transesophageal echocardiography compared to seven by transthoracic technique. By transesophageal echocardiography, mitral regurgitation was paravalvular in 24% compared with 4% by transthoracic technique. Left atrial spontaneous contrast was seen in 42% of the patients with a mitral prosthesis detected only by transesophageal echocardiography. Six patients had left atrial or left atrial appendage thrombus and in five patients they were detected only by transesophageal echocardiography. We conclude that transesophageal echocardiography should be a complimentary test to transthoracic studies in patients with suspected prosthetic valve dysfunction or for the follow-up of older tissue valves.     

Role of transoesophageal echocardiography in evaluation of cardiogenic embolism.

OBJECTIVE--To determine the value of transoesophageal echocardiography in the assessment of selected patients at risk of cardiogenic embolism or after it. DESIGN--Prospective comparison of the results of transoesophageal and transthoracic echocardiography. Transoesophageal echocardiography was performed with a 5 MHz single plane phased array transducer. SETTING--University teaching hospital. PATIENTS--100 patients referred for transoesophageal echocardiography after a cerebral ischaemic event or peripheral arterial embolism (n = 63), before percutaneous balloon dilatation of the mitral valve (n = 23), or before electrical cardioversion of atrial fibrillation (n = 14). RESULTS--Transthoracic echocardiography showed potential sources of embolism in four patients including left ventricular thrombus in two patients (with one false positive), left atrial appendage thrombus (n = 1), and patent foramen ovale (n = 1). Transoesophageal echocardiography showed 59 potential embolic sources in 45 patients including left atrial spontaneous echo contrast (n = 33), left atrial appendage thrombus (n = 13), left ventricular thrombus (n = 5), patent foramen ovale (n = 3), left ventricular spontaneous echo contrast (n = 2), mitral valve prosthesis thrombus (n = 1), mitral valve prolapse (n = 1), and pronounced aortic atheroma (n = 1). Transoesophagal echocardiography showed potential embolic sources in 36/53 (68%) patients with atrial fibrillation compared with 9/47 (19%) patients in sinus rhythm. Percutaneous balloon dilatation of the mitral valve was performed without embolic complications in 18 patients without left atrial thrombi and in three patients with small fixed thrombi in the left atrial appendage. It was cancelled in two patients with large thrombi in the left atrial appendage. Cardioversion was performed without embolic complications in 14 patients without left atrial thrombi. CONCLUSIONS--Transoesophageal echocardiography detects potential sources of embolism better than transthoracic echocardiography in selected patients at risk of cardiogenic embolism or after it.     

Primary cardiac angiosarcoma detected by magnetic resonance imaging but not by computed tomography

A 51-year-old man with a primary angiosarcoma of the right atrium is reported. The angiosarcoma was not detected by transthoracic echocardiography or computed tomography, but magnetic resonance imaging and transesophageal echocardiography did show the tumor of the right atrial free wall. We performed a transvenous endomyocardial biopsy of the tumor under the guidance of transesophageal echocardiography and made the pathological diagnosis. This case demonstrates the advantage of magnetic resonance imaging and transesophageal echocardiography for tumor detection over transthoracic echocardiography and computed tomography and the usefulness of transesophageal echocardiography for guiding the right atrial endomyocardial biopsy procedure.     

Role of transoesophageal echocardiography in evaluation of cardiogenic embolism.

OBJECTIVE--To determine the value of transoesophageal echocardiography in the assessment of selected patients at risk of cardiogenic embolism or after it. DESIGN--Prospective comparison of the results of transoesophageal and transthoracic echocardiography. Transoesophageal echocardiography was performed with a 5 MHz single plane phased array transducer. SETTING--University teaching hospital. PATIENTS--100 patients referred for transoesophageal echocardiography after a cerebral ischaemic event or peripheral arterial embolism (n = 63), before percutaneous balloon dilatation of the mitral valve (n = 23), or before electrical cardioversion of atrial fibrillation (n = 14). RESULTS--Transthoracic echocardiography showed potential sources of embolism in four patients including left ventricular thrombus in two patients (with one false positive), left atrial appendage thrombus (n = 1), and patent foramen ovale (n = 1). Transoesophageal echocardiography showed 59 potential embolic sources in 45 patients including left atrial spontaneous echo contrast (n = 33), left atrial appendage thrombus (n = 13), left ventricular thrombus (n = 5), patent foramen ovale (n = 3), left ventricular spontaneous echo contrast (n = 2), mitral valve prosthesis thrombus (n = 1), mitral valve prolapse (n = 1), and pronounced aortic atheroma (n = 1). Transoesophagal echocardiography showed potential embolic sources in 36/53 (68%) patients with atrial fibrillation compared with 9/47 (19%) patients in sinus rhythm. Percutaneous balloon dilatation of the mitral valve was performed without embolic complications in 18 patients without left atrial thrombi and in three patients with small fixed thrombi in the left atrial appendage. It was cancelled in two patients with large thrombi in the left atrial appendage. Cardioversion was performed without embolic complications in 14 patients without left atrial thrombi. CONCLUSIONS--Transoesophageal echocardiography detects potential sources of embolism better than transthoracic echocardiography in selected patients at risk of cardiogenic embolism or after it.     

Diagnostic value of transesophageal echocardiography in atrial septal aneurysm

Transthoracic and transesophageal echocardiography was performed in 40 consecutive adult patients with an atrial septal aneurysm. In 11 (27%) of 40 patients transthoracic echocardiography failed to demonstrate the lesion and the diagnosis was established by the transesophageal approach only. Interatrial shunting, assessed by echocardiographic contrast study and/or color flow mapping, was detected in 13 (54%) of 24 patients on transthoracic imaging and in 29 (76%) of 38 patients during transesophageal echocardiography. Identification of multiple fenestrations (n=9) and thrombi within the aneurysm (n=2) could be achieved only by transesophageal ultrasound. A cerebrovascular event of suspected embolic origin occurred in 20 (50%) of 40 patients; 11 (55%) of the 20 patients had repeated cerebral events. Except for mitral valve prolapse in 2 patients and spontaneous left atrial contrast phenomenon in 1 patient no other potential cardiac source of embolism could be identified by transesophageal echocardiography. A marked thickening of the aneurysm was present in 14 (70%) of 20 patients with a cerebrovascular event versus only 4 (20%) of 20 patients without a cerebrovascular event (p<0,01). The mechanism of embolization may be both primary thrombus formation within the aneurysm and paradoxical embolization through an interatrial communication as suggested by the findings on transesophageal ultrasound in 2 patients. Although the patients of this study represent a highly selected group it may be concluded that atrial septal aneurysm is a cardiac abnormality with embolic potential. Transesophageal echocardiography has to be regarded the imaging method of choice for evaluation of this lesion.     

Fenestrated Aneurysm of the Mitral Valve

Aneurysms of the cardiac valves remain rare. In this report, we describe the first case of a left ventricular to mitral valve aneurysm to left atrial shunt through a fenestrated aneurysm of the mitral valve diagnosed and successfully repaired under the guidance of transesophageal echocardiography. The transesophageal echocardiography provided substantial additional data to the transthoracic echocardiography, and was valuable in planning the surgical approach. Transesophageal echocardiography should be considered when clear-cut transthoracic echocardiographic interpretation cannot be made in patients with mitral regurgitation. (ECHOCARDIOGRAPHY, Volume 8, September 1991)     

Superiority of transesophageal echocardiography in detecting cardiac source of embolism in patients with cerebral ischemia of uncertain etiology

The diagnostic yield of transesophageal and transthoracic echocardiography for identifying a cardiac source of embolism was compared in 79 patients presenting with unexplained stroke or transient ischemic attack. There were 35 men and 44 women with a mean age of 59 years (range 17 to 84); 52% had clinical cardiac disease. Both transthoracic and transesophageal echocardiograms were performed using Doppler color flow and contrast imaging. Transesophageal echocardiography identified a potential cardiac source of embolism in 57% of the overall study group compared with only 15% by transthoracic echocardiography (p less than 0.0005). Compared with transthoracic echocardiography, transesophageal echocardiography more frequently identified atrial septal aneurysm associated with a patent foramen ovale (9 versus 1 of 79 patients, p less than 0.005), left atrial thrombus or tumor (6 versus 0 of 79 patients, p less than 0.05) and left atrial spontaneous contrast (13 versus 0 of 79 patients, p less than 0.0005). All cases of left atrial thrombus or spontaneous contrast were identified in patients with clinically identified cardiac disease. In the 38 patients with no cardiac disease, transesophageal echocardiography identified isolated atrial septal aneurysm and atrial septal aneurysm with a patent foramen ovale more frequently than transthoracic echocardiography (8 versus 2 of 38 patients, p less than 0.05). The two techniques had a similar rate of identifying apical thrombus and mitral valve prolapse. Overall, transesophageal echocardiography identified abnormalities in 39% of patients with no cardiac disease versus 19% for transthoracic echocardiography (p less than 0.005). Thus, transesophageal echocardiography identifies potential cardiac sources of embolism in the majority of patients presenting with unexplained stroke.(ABSTRACT TRUNCATED AT 250 WORDS)