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.     

Thrombosis of atrioventricular prosthesis. Contribution of transesophageal echocardiography]

The aim of this study was to assess the diagnostic value of transesophageal echocardiography for the detection of thrombosis of a mechanical mitral or tricuspid valve prosthesis. Twelve patients (mean age 54 +/- 12 years) out of a series of 39 patients operated between April 1988 and June 1989 for prosthetic valve dysfunction had valve thrombosis at operation (11 mitral and 1 tricuspid valve prosthesis). Transesophageal echocardiography was routinely performed preoperatively in addition to transthoracic Doppler echocardiography to search for an abdominal mass on the prosthetic valves. The largest diameter of the diastolic jet at the level of the prosthetic valve annulus was measured using transesophageal color flow Doppler in the 8 Starr-Edwards mitral valve prostheses and compared with 5 control valves. The results of transthoracic Doppler echocardiography and transesophageal echocardiography were compared with the operative findings. The specificity of transthoracic echocardiography for the positive diagnosis of prosthetic valve thrombosis was 18%. A thrombosis could be suspected in 10 of the 12 cases by transthoracic echocardiography giving a sensitivity of 83%. Eleven of the 12 abnormal masses on the prostheses were visualised by transesophageal echocardiography, a sensitivity of 91%. Detection of the masses on the arterial side was possible in all cases (10/10) but 5 of the 6 extensions of the thrombus into the ventricle could not be visualised. The diameter of the transprosthetic jet was less than 12 mm in 7 of the 8 thrombosed valves compared with greater than 15 mm in the 5 normal control prostheses.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

Regurgitation jets in mitral prosthesis studied using transesophageal echocardiography

STUDY OBJECTIVE: To analyze the regurgitant jets of mitral valve prostheses studied by transesophageal echocardiography. DESIGN: Prospective study of patients with mitral prostheses with or without suspicion of dysfunction. SETTING: Patients referred to the Echocardiology Department of the Instituto de Cardiologia in Madrid, some as outpatients. PATIENTS AND INTERVENTIONS: Twenty five patients with mitral valve prostheses (5 biological, 7 St Jude, 12 Bjork Shiley and 1 Hall Kaster). Ten male patients and fifteen female, mean age 50 years. Five also had aortic valve prostheses. In only 5 there was a suspicion of dysfunction. The transthoracic echos were done with phased array transducers and the transthoracic with 2.5 (18 patients) or 5 MHz (7 patients) transducers coupled to a commercial echocardiographer. The presence of regurgitant jets was looked for, as well as their origin, maximal area and length, their type and degree of turbulence. MAIN RESULTS: Only 3 mitral regurgitations were noticed by transthoracic echocardiography. All the mechanical prostheses and 80% of the biological ones had regurgitant jets by transesophageal echocardiography. The tilting disc prostheses had two physiological jets, the St. Jude 2, 3, or exceptionally only one central jet. The biological prostheses had one central regurgitant jet, that was smaller than those from the mechanical prostheses (p less than 0.05). There were ten malfunctioning prostheses (5 Bjork Shiley, 3 St Jude and 2 biological). The diagnosis of dysfunction was based on the abnormal origin of the jet (9 cases) or just simply on the characteristics of the regurgitation (turbulence). Four patients were submitted to surgery, all with dysfunctioning prostheses. CONCLUSIONS: Transthoracic echocardiography has a low sensitivity for detecting the regurgitant jets of mitral prostheses. All mechanical prostheses and 80% of biological ones have regurgitation by transesophageal echocardiography. The area and length of the jets are not so different between normal and malfunctioning prostheses in order to separate them. The abnormal jets are recognised because of their abnormal origin and/or their characteristics, with formation of mosaic in color coded Doppler echocardiography.     

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.     

In vivo magnetic resonance imaging and surgical histopathology of intracardiac masses: distinct features of subacute thrombi

We evaluated intracardiac masses in vivo, in situ and histologically to determine tissue properties revealed by magnetic resonance (MR) imaging. In 15 consecutive patients scheduled for cardiotomy, the cardiac chambers were studied preoperatively with MR imaging and echocardiography. Visual examination of one or more chambers was performed during cardiotomy for mitral valve replacement, aneurysmectomy, atrial septal repair and atriotomy. Six thrombi (1 atrial appendage, 5 ventricular) and 2 atrial myxomas were removed and subjected to histological analysis. All masses were detected preoperatively by MR imaging. The smallest was a subacute 3-mm mural clot in the left ventricle and was undetected by transesophageal and transthoracic echocardiography. The 3 subacute clots had homogeneously low MR signals, did not enhance with gadolinium and exhibited magnetic susceptibility effects; histopathology confirmed these clots to be avascular and laden with dense iron deposition related to hemoglobin breakdown products. The 3 organized clots had intermediate and heterogeneous MR signals and multiple areas of gadolinium enhancement. The 2 myxomas had low MR signals and gadolinium enhancement in the core and septal attachment; these areas had dense neovascular channels. Subacute thrombi appear to have MR features that are distinct from organized thrombi and myxomas, and MR images of subacute thrombi contrast sharply with normal cardiac structures, enabling detection of thin mural clots that may be echographically occult. These findings may be of value, because a subacute clot may be more likely than an organized thrombus to give rise to an embolus.     

Left atrial spontaneous echo contrast in mitral valve disease: an indicator for an increased thromboembolic risk

The incidence of left atrial spontaneous echo contrast was evaluated in 52 patients with isolated or predominant mitral valve stenosis (Group 1) and 70 other patients who had undergone mitral valve replacement (Group 2). All patients were studied by conventional transthoracic and transesophageal two-dimensional echocardiography. Spontaneous echo contrast could be visualized within the left atrium in 35 Group 1 patients (67.3%) (including 7 patients with sinus rhythm) and 26 Group 2 patients (37.1%) (all with atrial fibrillation). Patients with spontaneous echo contrast had a significantly larger left atrial diameter and a greater incidence of both left atrial thrombi and a history of arterial embolic episodes than did patients without spontaneous echo contrast. Association between spontaneous echo contrast and left atrial thrombi and a history of arterial embolization (considered individually or in combination) showed a high sensitivity and negative predictive value. It is concluded that spontaneous echo contrast is a helpful finding for identification of an increased thromboembolic risk in patients with mitral stenosis and after mitral valve replacement.     

Systemic embolism as a complication of percutaneous mitral valvuloplasty.

Systemic embolism is a potential and severe complication of percutaneous mitral valve dilatation. In our series of 80 cases, the incidence of systemic embolism was 3.75% (3 cases). Two cases occurred during the procedure itself. The cause of embolism was different in each case: cruoric thrombus formation occurred in 2 cases during or after dilatation, and was attributable to inappropriate heparinization, and catheter and guidewire thrombogenicity. In both cases heparin administration was delayed or given at a lower dosage. In the third case, calcific embolism occurred several days after valve dilatation. We think that the embolic calcified fragment was detached from the mitral leaflet at the time of or after balloon inflation. In these 3 cases, intraatrial thrombus mobilization was not the mechanism of systemic embolism. In 2 cases, transesophageal echocardiography had been performed before dilatation and excluded the presence of an atrial thrombus the day before the procedure. It is concluded that, together with mobilisation of left atrial thrombi, which can be adequately detected by transesophageal echocardiography, catheter-induced thrombi represent a significant cause of embolic complications and must be prevented by giving full-dose heparin during the total duration of the procedure. Calcific embolism may also occur, and may become more frequent if mitral valve balloon dilatation is proposed to a larger number of patients with valvular and subvalvular calcifications.     

Comparison of mono and bidimensional echocardiography in the diagnosis of atrial myxoma

The diagnosis of atrial myxoma, the most common cardiac tumour, has been greatly facilitated by the introduction of echocardiography. The principal echocardiographic features and the diagnostic pitfalls encountered in a personal series of 7 atrial myxomas (5 left and 2 right) studied by M mode and 2-dimensional echocardiography are reported. In M mode, left atrial myxoma is a relatively easy diagnosis when the tumour prolapses into the mitral orifice. On standard mitro-aortic scanning, it is recorded behind the anterior mitral leaflet as a mass of abnormal echos appearing shortly after mitral valve opening. The diagnosis is much more difficult or even impossible in nonprolapsing tumours. Right atrial myxomas, prolapsing into the tricuspid orifice, do not usually pose any diagnotic problems. 2-dimensional echocardiography shows its superiority in the early diagnosis of small, localised, relatively immobile and non-prolapsing tumours. The parasternal (long axis and transverse views), the apical (4 and 2 chamber views) and subxiphoid positions were the most useful incidences and the tumour was visualised as a more or less circumscribed mass of echos. In all cases, 2-dimensional echo provided information on the size, mobility, insertion and the length of the pedicle of the tumour. Atrial myxoma is being recognised more easily and more often nowadays by echocardiography, the diagnostic method of choice, and 2-dimensional studies should be preferred.     

Redundant Mitral Valve Simulating an Intracardiac Mass on Transesophageal Echocardiography

Cardiac ultrasound is a useful diagnostic modality for the evaluation of cardiac masses and tumors. However, normal cardiac structures and normal variants can mimic masses with both transthoracic echocardiography and transesophageal echocardiography. We report two patients in whom a redundant mitral leaflet simulated cardiac tumor attached to the mitral valve by transesophageal echocardiography. (ECHOCARDIOGRAPHY, Volume 11, May 1994)     

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.     

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.     

Transesophageal Echocardiography in Candidates for Percutaneous Balloon Mitral Valvuloplasty

Prior to percutaneous balloon mitral valvuloplasty (PBMV), mitral valve morphology and the presence of left atrial thrombi are usually evaluated by transthoracic two-dimensional and Doppler echocardiography (TTE). This study analyzes the impact of transesophageal echocardiography (TEE) in addition to TTE on the selection of candidates considered for PBMV for mitral stenosis. Seventy-five patients with severe mitral stenosis who were considered as appropriate candidates for PBMV based on TTE findings were studied. In 19 (25%) patients, TEE revealed findings that were essential for PBMV but were missed by TTE: left atrial thrombi (n = 14; including 13 in left atrial appendage), right atrial thrombus (n = 1), incomplete cor triatriatum (n = 1) and mitral valve vegetation (n = 1). In two other patients, a left atrial thrombus had been suspected by TTE but could be excluded by TEE. TEE and TTE revealed similar scores of thickening, calcification, and mobility of the mitral valve. Compared to TTE, thickening of the subvalvular apparatus was graded lower using horizontal plane TEE due to shadowing by the mitral valve (echo score 1.8 ± 0.8 vs 1.4 ± 0.7; P < 0.05) whereas results from longitudinal plane TEE were similar to TTE findings. The data show that due to the high prevalence of left atrial thrombi, TEE should be performed in addition to TTE in all patients prior to PBMV.     

Transesophageal echocardiography in the definition of intracardiac sources of emboli in patients with recent ischemic stroke

Using both transthoracic and transesophageal echocardiography we studied 13 consecutive patients with recent CT-proven ischemic stroke in which a carotid arteries high-resolution ultrasound study failed to detect thrombosis or other relevant atherosclerotic lesions in the pertinent arteries. The mean age was 53 years (range: 36-65). Two patients exhibited clinical signs of cardiac disease at physical examination i.e. absolute arrhythmia, mitral stenosis. Conventional transthoracic echocardiography allowed the detection of potential cardiac sources of emboli in 2/13 patients (15.4%): mitral stenosis in one patient and dilated cardiomyopathy in another. Transesophageal echocardiography was successfully performed without general sedation in all patients. Potential cardiac sources of emboli could be identified in 12/13 patients (92%). Left atrial thrombi were found in 3 patients: in two of them they were associated with rheumatic alterations of mitral valve leaflets; in the third patient a small thrombus was located inside a normal-sized, poorly contracting left atrial appendage. Left atrial appendage could be clearly visualized in all patients. A myxoid degeneration of a prolapsing mitral leaflet was found in 3 patients and an interatrial septum aneurysm in 2. Furthermore, at color-flow Doppler and contrast transesophageal echocardiography, 7 patients (54%) showed patency of the foramen ovale. In 5 of these patients paradoxical right to left shunting after cough or Valsalva manoeuvre could be evidenced. With reference to 11/13 patients with no clinical signs of cardiac disease at physical examination, subclinical potential cardiac sources of emboli could be detected at conventional transthoracic echocardiography in 1 and at transesophageal echocardiography in 10 patients (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Diagnosis of accessory mitral valve tissue by transesophageal echocardiography

Accessory mitral valve tissue is a rare cause of intracardiac mass and subvalvular left ventricular outflow tract obstruction. The preoperative diagnosis of this congenital anomaly has been facilitated by transthoracic two-dimensional and Doppler echocardiography. However, transthoracic two-dimensional echocardiography cannot identify or correctly diagnose all cases of accessory mitral valve tissue. We report a patient in whom an intracardiac mass detected by transthoracic echocardiography was definitively diagnosed as accessory mitral valve tissue by transesophageal echocardiography.     

Detection of aneurysms of the atrial septum using transesophageal echocardiography

In 7/340 patients (2.1%) examined by transesophageal echocardiography, aneurysms of the intraatrial septum were observed. In no patient were additional shunts present. In 3/7 patients mitral valve and in 2/7 patients tricuspidal valve prolapse was found. Intraatrial septum aneurysms seem to have a higher frequency than that indicated by transthoracical echocardiography. The incidence observed by transesophageal echocardiography corresponds to the incidence of pathological findings.     

Echography in surgical mitral insufficiency. Pathologic diagnosis and provision of the surgical procedure

The aim of this study was to determine the reliability of preoperative transthoracic and transesophageal echocardiography compared with the surgical findings in pure or dominant severe mitral regurgitation with respect to: the evaluation of the lesions, mechanism and etiology; the provision of the type of surgery (valve replacement or reconstruction); One hundred and fifty patients were divided into two groups: Group I (N = 120) in which preoperative assessment included transthoracic echo-Doppler coupled with color Doppler in the last 32 patients; Group II (N = 30) operated recently who underwent both transesophageal and transthoracic echo-Doppler examination. In Group I, the sensitivity of transthoracic echo in the evaluation of the etiological was 86% overall [100% in rheumatic valve disease (N = 28), 86% in degenerative or dystrophic valves (N = 72), 44% in endocarditis (N = 9), 87% in ischaemic dysfunction (N = 8)]. The echo evaluation of the mechanism of the regurgitation was also reliable with the exception of ruptured chordae in which direct visualisation of the rupture was only possible in 19 of the 64 cases (30%). The type of surgery predicted by echo was practiced in 87% of cases.     

Comparison of transthoracic and transesophageal echocardiography in evaluation of 47 Starr-Edwards prosthetic valves.

OBJECTIVES. Our objectives were to characterize by transesophageal echocardiography the normal appearance of the Starr-Edwards prosthetic heart valve and to compare the utility of transesophageal and transthoracic echocardiography in detection of valve abnormality. BACKGROUND. The Starr-Edwards prosthetic heart valve, the first mechanical valve to be used, has demonstrated excellent durability. METHODS. Fifty transthoracic and transesophageal echocardiographic studies on 37 patients with 47 Starr-Edwards prosthetic valves were analyzed retrospectively. Six cases of surgically confirmed infective endocarditis were studied. RESULTS. Vegetation or abscess formation, or both, was identified by transesophageal echocardiography in all six cases of infective endocarditis but was found in only one of these cases by transthoracic echocardiography. Thrombus was detected by transesophageal echocardiography in 9 of 11 patients with transient ischemic attacks or stroke and in 2 patients by transthoracic echocardiography with 3 confirmed at surgery. In 26 of the 30 patients with a mitral Starr-Edwards valve, the valve demonstrated a trivial or mild "closing volume" early systolic or holosystolic leak on transesophageal echocardiography alone. Transthoracic evaluation identified significant mitral regurgitation in six of the eight patients who had this finding on transesophageal echocardiography. Serial studies were performed to assess response to treatment or need for surgical intervention in eight patients. Seventeen valves have been implanted for 12 years; six of these had significant leakage without apparent cause, a finding not observed more recently implanted valves. CONCLUSIONS. These observations demonstrated the unique utility of transesophageal echocardiography in patients with Starr-Edwards prosthetic valve dysfunction, endocarditis or thrombus formation, and of the clear superiority of transesophageal echocardiography over transthoracic echocardiography in these situations.     

Use of transoesophageal echocardiography to detect left atrial thrombi before percutaneous balloon dilatation of the mitral valve: a prospective study.

OBJECTIVE--Systemic emboli related to atrial thrombi are a well known complication of percutaneous balloon dilatation of the mitral valve. The presence of left atrial thrombi therefore, is believed to be a contraindication to balloon dilatation. The purpose of this study was to determine the frequency of left atrial thrombi in patients referred for balloon dilatation of the mitral valve, the added benefit of pre-procedural transoesophageal echocardiography, and to identify factors that predicted left atrial thrombi. DESIGN--Prospective study over a 14 month period of 20 consecutive patients by cross sectional transthoracic echocardiography 24-48 hours before balloon dilatation of the mitral valve and by transoesophageal echocardiography immediately before the procedure. RESULTS--One patient had a left atrial thrombus detected by transthoracic study. Two patients (10%) had left atrial thrombi identified by transoesophageal echocardiography. In both valve dilatation was not attempted and the thrombi were confirmed at surgery. The remaining 18 patients all underwent successful balloon dilatation of the mitral valve without clinical evidence of an embolic event. No association was found between patient age, mitral valve area, transmitral gradient, left atrial size, presence of atrial fibrillation, severity of mitral regurgitation, cardiac output, or the presence of left atrial swirling and an increased prevalence of atrial thrombi. CONCLUSION--Left atrial thrombi are often seen despite long term systemic anticoagulation in patients referred for balloon dilatation of the mitral valve. The frequency of unsuspected left atrial thrombi detected by transoesophageal echocardiography was similar to the reported frequency of embolic events after balloon dilatation of the mitral valve. Transoesophageal echocardiography for the identification of left atrial thrombi is strongly recommended in all patients before balloon dilatation of the mitral valve including those treated with systemic anticoagulation and those who have had a normal transthoracic echocardiographic study.     

Use of transoesophageal echocardiography to detect left atrial thrombi before percutaneous balloon dilatation of the mitral valve: a prospective study.

OBJECTIVE--Systemic emboli related to atrial thrombi are a well known complication of percutaneous balloon dilatation of the mitral valve. The presence of left atrial thrombi therefore, is believed to be a contraindication to balloon dilatation. The purpose of this study was to determine the frequency of left atrial thrombi in patients referred for balloon dilatation of the mitral valve, the added benefit of pre-procedural transoesophageal echocardiography, and to identify factors that predicted left atrial thrombi. DESIGN--Prospective study over a 14 month period of 20 consecutive patients by cross sectional transthoracic echocardiography 24-48 hours before balloon dilatation of the mitral valve and by transoesophageal echocardiography immediately before the procedure. RESULTS--One patient had a left atrial thrombus detected by transthoracic study. Two patients (10%) had left atrial thrombi identified by transoesophageal echocardiography. In both valve dilatation was not attempted and the thrombi were confirmed at surgery. The remaining 18 patients all underwent successful balloon dilatation of the mitral valve without clinical evidence of an embolic event. No association was found between patient age, mitral valve area, transmitral gradient, left atrial size, presence of atrial fibrillation, severity of mitral regurgitation, cardiac output, or the presence of left atrial swirling and an increased prevalence of atrial thrombi. CONCLUSION--Left atrial thrombi are often seen despite long term systemic anticoagulation in patients referred for balloon dilatation of the mitral valve. The frequency of unsuspected left atrial thrombi detected by transoesophageal echocardiography was similar to the reported frequency of embolic events after balloon dilatation of the mitral valve. Transoesophageal echocardiography for the identification of left atrial thrombi is strongly recommended in all patients before balloon dilatation of the mitral valve including those treated with systemic anticoagulation and those who have had a normal transthoracic echocardiographic study.