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.     

Simultaneous Right and Left Atrial Appendage Thrombus in a Patient with Atrial Fibrillation: A Lesson to Remember

We report a case of simultaneous right and left atrial appendage thrombi in a 76‐year‐old‐man with atrial fibrillation. Although transesophageal echocardiography is considered a routine diagnostic procedure, complete and comprehensive visualization of both atrial appendages is of paramount importance, particularly with the introduction of new therapeutic options like left atrial appendage exclusion devices. We expect to raise awareness among clinicians of the prevalence and implications of bilateral atrial appendage thrombi in common clinical practice.     

Right Atrial Thrombi and Depressed Right Atrial Appendage Function After Cardioversion of Atrial Fibrillation

BACKGROUND: It has been shown that cardioversion of atrial fibrillation may result in left atrial chamber and appendage dysfunction and cause new thrombi in the left atrium. The aim of this prospective study was to investigate right atrial appendage function and assess the incidence of new right atrial thrombi after electrical cardioversion. METHODS: Transthoracic echocardiography was performed in 25 patients 4 h before and at 24 h and 7 days after electrical cardioversion to determine right and left atrial mechanical function (internal atrial defibrillation, n = 16; external electrical cardioversion, n = 9), as assessed by peak A wave velocities derived from the transtricuspid and transmitral velocity profiles. In addition, transesophageal echocardiography was performed 4 h before and 24 h after cardioversion to evaluate postcardioversion thrombus formation in the right and left atrial chambers and to assess right and left atrial appendage function. The degree of spontaneous echo contrast was noted, and peak emptying velocities of the appendages were measured before and after cardioversion. RESULTS: Peak emptying velocities of both the right atrial appendage (mean +/- SD, 0.23 +/- 0.1 vs 0.32 +/- 0.11 m/sec; P = 0.02) and the left atrial appendage (0.3 +/- 0.15 vs 0.4 +/- 0.15 m/sec; P = 0.01) were significantly lower 24 h after cardioversion compared with 4 h before cardioversion, respectively. The degree of spontaneous echo contrast increased in the left atrium after cardioversion from 1.0 +/- 1.2 to 1.9 +/- 2.1 (P = 0.02), and in the right atrium, it increased from 0.8 +/- 1.1 to 1.2 +/- 1.1 (P = 0.1) after cardioversion. Peak A wave transtricuspid velocity increased from 0.26 +/- 0.05 m/sec at 24 h to 0.38 +/- 0.06 m/sec (P = 0.001) after 7 days; respective values for transmitral peak A wave velocity were 0.39 +/- 0.15 and 0.54 +/- 0.16 m/sec (P = 0.009). No thrombi were found in either the right or left atrium before cardioversion. In two patients, new thrombi in the right atrium were detected 24 h after internal atrial defibrillation. Thrombi were located at the superior rim of the fossa ovalis in both patients with patent foramen ovale. Another patient had developed a thrombus in the left atrial appendage. CONCLUSIONS: Electrical cardioversion may not only cause left atrial chamber and appendage dysfunction and left atrial thrombi but also lead to depressed right atrial appendage function and the generation of new thrombi in the body of the right atrium.     

Usefulness of transesophageal echocardiography for the detection of left atrial thrombi in patients with rheumatic heart disease

Transesophageal (TEE) and transthoracic (TTE) echocardiograms were performed in 110 patients with rheumatic heart disease to evaluate the usefulness of these methods for the detection of left atrial thrombi. TEE was better than TTE for detecting left atrial thrombi (21 vs 9). The thrombi not detected by TTE were in the left atrial appendage in ten and over the left atrial posterior wall in two. Patients with left atrial thrombi had significantly smaller mitral valve area (P less than 0.01) and greater left atrial dimension (P less than 0.05) than those without. All patients with left atrial thrombi had atrial fibrillation. Thirty-one patients underwent surgical intervention and 13 were found to have left atrial thrombi. TEE detected left atrial thrombi in all 13 patients with a sensitivity of 100%, specificity of 100%, and accuracy of 100%, while TTE detected left atrial thrombi in only nine of these 13 patients with a sensitivity of 69.2%, specificity of 100%, and accuracy of 87.1%. Thus, TEE is superior to TTE for the detection of left atrial thrombi, especially for those thrombi located in the left atrial appendage and along the left atrial posterior wall.     

先天性左房瘤1例报告及文献复习

先天性左房瘤是一种罕见的心脏畸形。至今国外文献仅报告４０余例，国内仅７例。我们报告１例５岁女孩术前无症状，胸片发现左心缘扩大，超声心动图明确诊断。在体外循环下行瘤体切除，治愈出院。结合文献对本病临床特点、诊断、治疗及预后进行讨论。     

Transesophageal echocardiographic evidence of atrial fibrillation with systolic flow in the right atrial appendage and systolic reversal pulmonary flow in a patient with DDD permanent pacing

We report the case of a patient with atrial fibrillation on standard electrocardiogram who underwent transesophageal echocardiography to rule out presence of thrombi in heart cavities. Pulsed-wave Doppler investigation revealed multiphasic waves consistent with atrial fibrillation in the left atrial appendage, while in the right atrial appendage, a biphasic flow was registered after QRS depolarization. Some hypotheses are made about the origin of this signal.     

Congenital aneurysm of the left atrial appendage

Congenital aneurysm of the left atrial appendage is quite infrequent.Most instances are asymptomatic. Patients can report a varietyof symptoms, one of the most frequent being onset of auriculartachyarrhythmia. Various imaging techniques are useful in diagnosisand allow the differential diagnosis with other pathologies. We describe the case of a 24-year-old male with congenital aneurysmof the left atrial appendage. The patient presented with auricularfibrillation. Diagnosis was based on transthoracic and trans-esophagealechocardiography, and the patient was treated by surgical resectionof the aneurysm under extracorporeal circulation.     

Left atrial appendage aneurysm: a rare cause of paroxysmal supraventricular tachycardia

Left atrial appendage aneurysm is a rare abnormality and a diagnostic dilemma in patients with cardiomegaly. Patients most commonly present with atrial tachyarrhythmias and thromboembolic events. Resection of the aneurysm is usually curative. We report herein the case of a 27-year-old man with massive left atrial appendage aneurysm diagnosed incidentally in the course of pre-operative evaluation for a non-cardiac surgery. The marked cardiomegaly detected in a routinely ordered pre-operative chest X-ray and the history of previous episodes of palpitation accompanied by chest discomfort guided us to the diagnosis. The diagnosis was made by transthoracic echocardiography and confirmed by angiography and then surgery.     

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.     

Giant intrapericardial aneurysm of the left atrial appendage

A young patient is reported with an aneurysm of the left atrial appendage having supraventricular arrhythmias and a period of chest pain accompanied by a rise in cardiac enzymes. Compression of the left anterior descending coronary artery by the aneurysm was felt to be responsible for the myocardial injury.     

Interobserver variability in the detection of spontaneous echo contrast, left atrial thrombi, and left atrial appendage thrombi by transoesophageal echocardiography.

OBJECTIVE--To assess the interobserver variability between two observers from different echocardiographic laboratories. DESIGN--Two observers reviewed video recordings blinded to the other's diagnosis. In part I (n = 88), they determined interobserver variability for spontaneous echo contrast, left atrial thrombi, and appendage thrombi. No diagnostic criteria for thrombi were defined. In part II (n = 85), diagnostic criteria for thrombi were defined. RESULTS--Part I: Both observers agreed in diagnosing spontaneous echo contrast in 97%, left atrial thrombi in 90%, left atrial appendage thrombi in 94%. Part II: With predefined criteria no disagreement occurred in diagnosing left atrial thrombi. In the diagnosis of left atrial appendage thrombi both observers agreed in 89%. The mean diameters of the 10 thrombi on which the observers agreed were greater than of the nine appendage thrombi on which they disagreed. CONCLUSIONS--Interobserver variability in the diagnosis of spontaneous echo contrast is low. Defined criteria decrease interobserver variability for left atrial and appendage thrombi, although one third of the thrombi diagnosed by one observer were not confirmed by the other. Interobserver variability is high in the assessment of small structures (< 15 mm) within the left atrial appendage.     

Left atrial appendage function in patients with mitral stenosis in sinus rhythm.

AIMS: Left atrial appendage thrombi are believed to be the source of embolism in patients with rheumatic mitral stenosis in atrial fibrillation. There are a few studies which search the effects of left atrial appendage dysfunction in patients with mitral stenosis in sinus rhythm. METHODS AND RESULTS: Left atrial appendage function and flow patterns in 41 patients with rheumatic mitral stenosis in sinus rhythm and 11 healthy subjects were studied by transoesophageal echocardiography. Left atrial appendage flow profiles were recorded within the proximal third of the appendage. The left atrial appendage ejection fraction was expressed as (maximal area of appendage minimal area of appendage)/maximal area of appendage. In addition, two-dimensional imaging was used to determine the presence of spontaneous echocardiographic contrast and thrombus formation. Patients with mitral stenosis in sinus rhythm had significantly decreased left atrial appendage emptying and filling velocities compared to controls (0.40+/-0.15m/s vs 0.82+/-0.19 m/s and 0.42+/-0.21 m/s vs 0.68+/-0.28, respectively, P<0.001 and P<0.05). Compared with the control subjects, patients with mitral stenosis had significantly greater maximal area of the appendage and had reduced left atrial appendage ejection fraction (5.3+/-2.2 cm(2) vs 2.4+/-0.5 cm(2) and 50+/-16% vs 70+/-7%, respectively, P<0.001 and P<0.05). Of the patients with mitral stenosis in sinus rhythm, seven patients had spontaneous echocardiographic contrast and one of these had left atrial appendage thrombus. Compared with patients without spontaneous echocardiographic contrast, patients with spontaneous echocardiographic contrast had decreased left atrial appendage ejection fraction (33+/-21% vs 54+/-13%,P <0.01). One of the patients with mitral stenosis had central retinal artery occlusion, but thrombus was not observed in left atrial appendage. CONCLUSION: The study found that left atrial appendage dysfunction may occur in patients with mitral stenosis in sinus rhythm.     

非瓣膜病心房颤动病人电复律前后左心房功能变化研究

目的评价经食道超声心动图(TEE)对非瓣膜病心房颤动(房颤)病人电复律前后左心房功能变化.方法选择房颤持续2周以上的非瓣膜疾病病人18例,其中原发性高血压6例,扩张型心肌病6例,脑血栓4例,缺血性心肌病2例.应用TEE确定左心房内无血栓后行电复律,转为窦性心律者测定左心耳血流最大速度及流速积分,肺静脉血流最大速度及流速积分、二尖瓣血流最大速度、流速积分及减速时间.结果左心耳排空速度于复律后显著减少,有显著性差异(P＜0.05),排空指数增加(P＞0.05),电复律后肺静脉收缩期、舒张期最大流速及其流速积分比值无显著差异(P＞0.05),收缩期最大流速积分在左、右肺静脉均有显著差异(P均＜0.05).复律前后舒张期最大流速积分在右肺静脉有显著性差异(P＜0.05),左肺静脉差异不显著(P＞0.05).二尖瓣血流E波最大速度及E波与A波比值(E/A)增加.结论适合的抗凝治疗及TEE确认心房内无附壁血栓后进行电复律治疗,安全又无并发症.TEE能评价房颤病人电复律后的左心房功能变化.电复律后心房的电活动及机械活动均微弱,能引起左心房功能不全及栓塞,所以心房功能完全恢复前均有必要进行抗凝治疗.     

Congenital giant aneurysm of the left atrial appendage mimicking pericardial absence case report

A 25-year-old man was found to have an abnormal cardiac contour on a chest radiograph, and was referred. Transesophageal echocardiography suggested herniation of the left atrial appendage (LAA) through a gap in the pericardium, and magnetic resonance imaging indicated congenital partial absence of the pericardium. Cardiac dysfunction was caused by compression from the enlarged left atrium and thrombi were thought to be present in the appendage, so surgery was performed. The intraoperative diagnosis was congenital LAA aneurysm. Although distinguishing between congenital LAA aneurysm and congenital absence of the pericardium is reported to be possible with magnetic resonance imaging, we were unable to so in this case.     

Clinical significance of perfusion imaging of the left atrial wall and structures in its cavity by contrast echocardiography.

This study examined whether myocardial contrast echocardiography (MCE) can visualize left atrial appendage myocardial perfusion using transesophageal echocardiography (TEE) with intracoronary injection of sonicated albumin. We also evaluated blood flow into normal structures (i.e. muscular trabeculae) and abnormal masses (i.e. fresh thrombi and myxomas) within the left atrium by MCE. TEE images were obtained with a biplane or multiplane 5 MHz transducer in 16 patients without significant coronary artery occlusive disease. Left atrial appendage myocardium was divided into 4 segments in both the transverse and longitudinal planes, and contrast opacification of each segment during MCE was visually evaluated by 2 independent observers. Visual assessment of contrast opacification of prominent muscular trabeculae within the left atrial appendage (6 patients), and of left atrial or left atrial appendage thrombi (4 patients), was also performed. The ratio of background-subtracted peak videointensity from muscular trabeculae or thrombi versus left atrial appendage myocardium was determined as corrected peak videointensity. In 3 patients with myxomas, contrast opacification of the tumor was visually assessed. Ninety-six segments of left atrial appendage myocardium were visually analyzed. Contrast opacification of the left atrial appendage myocardium was identified in 92 of 96 segments (96%, 95% confidence interval 0.90-0.98) by Observer 1 and in 91 of 96 segments (95%, 95% confidence interval 0.88-0.98) by Observer 2. MCE also enhanced the imaging of left atrial appendage muscular trabeculae, but not of left atrial or left atrial appendage thrombi. Corrected peak videointensity from thrombi was significantly lower than that from muscular trabeculae (0.15 +/- 0.11 vs 0.95 +/- 0.18, p < 0.05). All myxomas were distinctly opacified by MCE. Transesophageal MCE with intracoronary injection of sonicated albumin can image left atrial appendage myocardial perfusion. MCE allows the evaluation of blood flow into normal structures and abnormal masses within the left atrium.     

Transesophageal echocardiographic diagnosis of thrombus in accessory lobes of the left atrial appendage

Fifty-four percent of left atrial appendages have two lobes. The number ranges from one to four lobes. We describe three patients with accessory lobes of the left atrial appendage studied with multiplanar transesophageal echocardiography (TEE). In one patient there was evidence of thrombi in the accessory lobe.     

The dangerous fifth chamber: congenital left atrial appendage aneurysm

Aneurysms of the left atrial appendage are extremely rare. Enlargement of the left atrial appendage can be congenital or acquired. Dysplasia of the left atrial muscles leads to congenital left atrial appendage aneurysm and usually presents as atrial tachyarrhythmia or embolic events in the second or third decade of life. We report a case of an asymptomatic 12-year-old child with a congenital left atrial appendage aneurysm. Transthoracic and transoesophageal echocardiography demonstrated a large left atrial appendage aneurysm without thrombus or spontaneous echo-contrast. The patient was successfully treated with surgical resection of the aneurysm.     

Atrial Appendage Thrombosis Risk Is Lower for Atrial Flutter Compared with Atrial Fibrillation

Background

The risk of stroke and thromboembolism in atrial fibrillation is established. However, the evidence surrounding the risk of thromboembolism in patients with atrial flutter is not as clear. We hypothesized that atrial flutter would have indicators of less risk for thromboembolism compared with atrial fibrillation on transesophageal echocardiography, thereby possibly leading to a lower stroke risk.

The use of transesophageal echocardiography to avoid left atrial thrombus during percutaneous mitral valvuloplasty

During mitral balloon valvuloplasty, transesophageal echocardiography (TEE) has been employed for the accurate placement of the transseptal needle, guide wires, and balloon catheters and to provide an immediate evaluation of the results of the procedure. We describe a case demonstrating that TEE can be used to avoid a left atrial appendage thrombus during the placement of wires and catheters. With TEE guidance, we feel left atrial appendage thrombi are no longer an absolute contraindication to percutaneous mitral valvuloplasty. © 1993 Wiley-Liss, Inc.     

Aneurysm of the left atrial appendage.

A 2-year old asymptomatic girl is presented in whom the chest x-ray film led to the discovery of a grossly distorted cardiac shadow. Angiocardiography showed a giant aneurysm originating from the left atrium. At operation an intrapericardial aneurysm of the left atrial appendage, measuring 12 X 4 X 4 cm, was found. It communicated with the left atrium through an orifice measuring 3 cm. The aneurysm was excised.