Uncommon intraventricular thrombus formation between the posterior mitral leaflet and the lateral left ventricular wall

Transthoracic echocardiography demonstrated an intraventricularmass between the posterior mitral leaflet and the lateral leftventricular (LV) free wall in a 61-year-old man. Because ofthis uncommon localization an intracardial tumor, an endocarditisof the mitral valve or an intraventricular thrombus was suspected.Magnetic resonance imaging (MRI) ruled out an intracardial tumorand revealed a myocardial scarring of the LV free wall coveredby an intraventricular thrombus by late gadolinium enhancement.MRI can distinguish subacute clots—which do not enhanceafter contrast material injection—from organized thrombi.The characterization of thrombi can be used to predict the riskof embolism, which is higher for subacute clots than for organizedthrombi.     

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.     

Prevalence of left atrial thrombus in rheumatic mitral stenosis with atrial fibrillation and its response to anticoagulation: a transesophageal echocardiographic study

BACKGROUND: The frequency of occurrence of left atrial thrombi, and the effect of anticoagulation in patients with rheumatic mitral stenosis and atrial fibrillation is not well established. This study was conducted to evaluate the occurrence of left atrial body and left atrial appendage clots in patients with rheumatic mitral stenosis and atrial fibrillation, and to document the effect of long-term anticoagulation on clot dissolution. METHODS AND RESULTS: Consecutive patients with severe rheumatic mitral stenosis and atrial fibrillation were assessed by transesophageal echocardiography. Those with left atrial body or left atrial appendage clots were anticoagulated with oral nicoumalone. Transesophageal echocardiography was then repeated in patients on anticoagulation who were on regular follow-up, and in whom percutaneous transvenous mitral commissurotomy could be considered. Of the 490 patients studied, 163 had left atrial body or left atrial appendage clots. A repeat transesophageal echocardiographic examination was done in 50 patients who had optimal anticoagulation for a period of 6 months. Only 2 of the 17 patients who had left atrial body clots had successful clot dissolution after long-term anticoagulation, while the left atrial appendage clots disappeared in 31 of 33 patients (p<0.001). CONCLUSIONS: Left atrial clots are present in a third of patients with severe rheumatic mitral stenosis and atrial fibrillation. Isolated left atrial appendage clots in patients with rheumatic mitral stenosis and atrial fibrillation can disappear with long-term anticoagulation, while thrombi that extend into the left atrial body may persist despite optimal anticoagulation.     

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.     

Diagnosis of abnormal intra-atrial echoes. Contribution of transesophageal echocardiography]

The aim of this study was to evaluate the results of transesophageal echocardiography in the diagnosis of abnormal intraatrial echoes detected by transthoracic echocardiography. Patients with active endocarditis, mitral stenosis, and valve prostheses were excluded. The 47 patients (28 women and 19 men) were classified into 4 groups according to the results of transesophageal echocardiography. Group I: normal (7 cases), "phantom echos"; Group II: anatomical variants (9 cases), Chiari apparatus, muscular spur; Group III: pseudo-tumours (7 cases); retro-atrial haematoma, mitral valve prolapse, interatrial septal aneurysm; Group IV: cardiac masses (24 cases). This group comprises: typical myxomas (10 cases), typical thrombi (2 cases), localised atypical masses, relatively immobile and non-prolapsing: 5 myxomas, 1 metastasis, 2 thrombi. The results of this study suggest that transesophageal echocardiography is very useful in diagnosing suspected abnormal intraatrial echos observed on conventional transthoracic examination. However, the nature of the mass may remain obscure.     

Evaluation by electron beam computed tomography of intracardiac masses suspected by transoesophageal echocardiography.

OBJECTIVES: To assess the suitability of electron beam computed tomography (EBT) in evaluating and subsequently managing cardiac masses suspected as a result of examination by transthoracic and transoesophageal cross sectional echocardiography. DESIGN AND PATIENTS: In 76 consecutive patients with suspected cardiac masses, the impact of the EBT examination was analysed by reviewing whether EBT examination altered management by confirming or excluding a mass, whether EBT imaging substantially contributed to decision-making, and lastly whether EBT influenced the decision to operate on the patient. RESULTS: EBT modified the diagnosis or confirmed results which had been questionable with cross sectional echocardiography in 53 cases (70%): these cases included those with anatomical features such as dense calcifications or fatty structures (n = 20), lipomatous lesions (n = 5), equivocal thrombi (n = 5), pericardial masses (n = 5), or hydatid cysts (n = 2). EBT gave information over and above cross sectional echocardiography in all patients with malignant tumours (n = 16) by providing a better delineation of the relation between intracavity masses and normal structures, including the mural site of tumour attachment and tumour extension to the great vessels and the adjacent extracardiac mediastinal structures. EBT provided no additional information over cross sectional echocardiography in the remaining patients (n = 23), particularly in those with myxomas (n = 11) or small valvar lesions (n = 6). EBT only confirmed that the lesion was well demarcated, limited in extent, or not associated with a mass. CONCLUSIONS: EBT has considerable potential for clinical management and surgical planning and may help clinicians to decide against surgery, particularly in patients with unresectable tumours.     

Imaging of intracardiac thrombus

Intracardiac thrombus is an important clinical condition because of its potential complications. Detection of ventricular thrombi is generally performed by transthoracic echocardiography while atrial thrombi are generally evaluated by transesophageal echocardiography. Contrast-enhanced computerized tomography is more sensitive for detecting ventricular and atrial thrombi than transthoracic echocardiography, but the technique has been demonstrated to be inferior to transesophageal echocardiography for displaying atrial thrombi. Cardiac magnetic resonance imaging provides superior specificity for evaluation of tissue characteristics and helps to differentiate thrombi from other masses.     

The contribution of magnetic resonance imaging to the evaluation of intracardiac tumors diagnosed by echocardiography

MAgnetic resonance (MR) imaging was performed in 14 patients with intracavitary cardiac tumors diagnosed by echocardiography. Except in the patients whose echocardiograms were diagnostic of atrial myxomas, this modality contributed important additional anatomic information regarding the tumor's relationship to the normal intracardiac structures and/or its extension to the adjacent vascular and mediastinal structures. The MR findings correlated extremely well with the findings in all 12 patients who underwent surgical exploration or postmortem examination, and in the other two patients, MR guided the decision to obtain transvenous biopsy samples of their right heart masses.     

Detection of left atrial thrombi by echocardiography.

A group of 111 patients with mitral valve disease was studied by M-mode and two-dimensional echocardiography. Five left atrial thrombi were demonstrated, two of which had probably been the source of previous embolic events. Two-dimensional echocardiography was superior to M-mode in providing spatial orientation. Using multiple cross-sections the exact localisation and the size of the thrombus formation could be estimated. Thrombus localisations at the upper, lateral, and septal atrial walls, normally inaccessible to the single-beam technique, were successfully imaged. Even two-dimensional echocardiography, however, constitutes an imperfect method. By comparison with the findings at surgery only one-third of confirmed thrombi could be detected non-invasively. According to their localisation seven clots in the appendage were missed by the ultrasound method. One further thrombus fixed to the upper left atrial wall near the entrance of the upper pulmonary veins was also undetected by echocardiography. Despite these limitations, the information provided by echocardiography can be most helpful in patient management. M-mode, in combination with two-dimensional echocardiography, is therefore recommended in all patients with mitral stenosis before diagnostic or therapeutic procedures are undertaken.     

Differential diagnosis of cardiac masses using contrast echocardiographic perfusion imaging

OBJECTIVES: We investigated the usefulness of echocardiographic contrast perfusion imaging in differentiating cardiac masses. BACKGROUND: Two-dimensional echocardiography is the primary diagnostic modality for cardiac masses. However, differentiation between the different types of cardiac masses may be difficult at times. We hypothesized that echocardiographic contrast perfusion imaging would differentiate the neo-vascularization of malignancies from the avascularity of thrombi and the sparse vascularity of stromal tumors. METHODS: Sixteen patients with cardiac masses underwent power-modulation imaging after echocardiographic intravenous contrast administration. Pixel intensities in the mass and an adjacent section of myocardium were analyzed visually and by dedicated software. All masses had a pathologic diagnosis or resolved after anticoagulation. In a subset of patients, video-intensity curves of contrast replenishment in the mass and myocardium over time were generated. The post-impulse steady-state pixel intensity (A) and initial rate of contrast replenishment after impulse (beta) were compared with an index of blood vessel area on pathology. RESULTS: In seven of 16 patients, contrast enhancement resulted in greater pixel intensity in the mass than in the adjacent myocardium. All of these masses were classified pathologically as malignant (n = 6) or benign and vascular (n = 1). Nine masses demonstrated decreased pixel intensity, compared with the myocardium, and were diagnosed pathologically as myxomas (n = 2) or thrombi (n = 5), or they resolved with anticoagulation (n = 2). For the subset of patients, beta correlated with the vessel area index (r = 0.60). CONCLUSIONS: Echocardiographic contrast perfusion imaging aids in the differentiation of cardiac masses. Compared with the adjacent myocardium, malignant and vascular tumors hyper-enhanced, whereas stromal tumors and thrombi hypo-enhanced.     

Right atrial myxoma: unusual clinical presentation and atypical glandular histology.

A 57-year-old black female presented with a 1-month of right-sided congestive heart failure and clinical evidence of pulmonic and tricuspid valvular stenosis and insufficiency. The echocardiographic examination and ventriculography demonstrated a large right atrial tumor interfering with the function of both right-sided valves. The patient underwent successful surgical resection of the tumor. Histologically, the tumor had cellular areas typical of myxoma, as well as glandular areas, a feature which has been described very rarely in this lesion. Electron microscopy of the glandular zones, which has never been reported previously, shown cells having essential homology with the usual myxoma elements. The atypical histopathology of this lesion supports the theory that atrial myxomas are true neoplasms, and are not derived from unusually organized mural thrombi.     

Intracardiac mural thrombus mimicking atrial myxoma in the antiphospholipid syndrome.

A wide spectrum of cardiac involvement including valvular lesions, myocardial infarction and myocardial dysfunction has been reported in patients with antiphospholipid antibodies (aPL), suggesting that cardiac manifestations may be part of the antiphospholipid syndrome (APS). We describe 3 patients (2 with primary APS and one with APS and SLE) who were found to have right atrial masses by echocardiography (transthoracic and/or transesophageal) and/or angiography, which were felt preoperatively to be atrial myxomata. Pathological examination of resected material showed only organized thrombus with calcification. We describe outcome 12 months to 7 years after resection of thrombus and document possible recurrence in one patient after 7 years. Intracardiac mural thrombus may be an additional cardiac manifestation of the APS, and presents considerable diagnostic confusion in its differentiation from atrial myxomata.     

Hemodynamic consequences of left atrial myxomas as assessed by Doppler ultrasound

Seven patients with left atrial (LA) myxoma who were studied by M-mode, two-dimensional, and Doppler echocardiography and who underwent surgical excision of the tumor are described. In six patients, the myxoma was attached to the lower interatrial septum and was protruding through the mitral valve (MV) during diastole. Significant MV obstruction (mean diastolic gradient of 16 mm Hg) was detected by Doppler in only one patient and was confirmed by hemodynamic studies; another patient had only a small gradient (peak 8 and mean 4 mm Hg). Mild mitral regurgitation (MR) was found preoperatively in four of five patients who underwent left ventriculography, but was not detected by Doppler. Postoperatively, however, five patients were found to have mild MR and one patient had moderate MR by Doppler. The use of Doppler echocardiography can provide important additional information regarding the hemodynamic consequences of LA myxomas.     

Identification of unusual conditions after atrial septal defect repair by systematic transthoracic echocardiographic assessment

Background: There is a lack of echocardiographic studies to address the detection of atrial masses and abnormal venous connections in patients with secundum atrial septal defect (ASD) repair. This study sought to demonstrate that with proper technique, these unusual conditions could be diagnosed confidently by transthoracic echocardiography. Method: We performed a retrospective review of all repaired ASD patients of all ages with follow‐up echocardiography done at Beijing Anzhen Hospital from year 1999 to 2005. Clinical and echocardiographic features of patients with aforementioned conditions were evaluated. Results: Systematic echocardiographic protocol identified 11 patients with unusual conditions, in whom four patients had atrial masses (three atrial thrombi, one inflammatory pseudotumor) and seven patients had abnormal venous connections (two inadvertent diversion of inferior vena cava to left atrium, five previously unrecognized partial anomalous pulmonary venous connections). Conclusion: Atrial masses and abnormal venous connections could be diagnosed through a systematic echocardiographic approach in evaluating patients with ASD repair.     

Bilateral atrial myxomas. Echocardiographic considerations

In this report we describe a patient with bilateral atrial myxomas, which were diagnosed preoperatively by echocardiography and angiography, and successfully removed. The excised tumor mass consisted of mobile right and left atrial myxomas connected by a common stalk which passed through the atrial septum, collectively resembling the shape of a dumbbell. Preoperative echocardiographic and angiographic observations were instrumental in planning the surgical approach, and correlated well with intraoperative findings and with the anatomic configuration of the intact pathologic specimen. Diagnostic aspects of echocardiography are emphasized as they relate to both isolated and bilaterally-occurring atrial myxomas.     

Organized left atrial mural thrombus demonstrated by coronary angiography

Small coronary artery fistulas terminating at the site of adherent, organized mural thrombi in the left atrial appendage were observed during selective coronary angiography in patients with mitral stenosis. The angiographic features of this abnormality can be distinguished from those of cardiac tumors, vascular malformations, and coronary artery fistulas that are not associated with organized thrombus. This coronary angiographic abnormality may indicate the presence of left atrial thrombus that is not revealed by echocardiography and is not manifest clinically by systemic emboli. The size of the collection of radiographic contrast material in the left atrium is not proportional to the size of the thrombus.     

Concomitant lipomatous hypertrophy and left atrial mass: Distinguishing benign from malignant

Masses in and near the interatrial septum may be either benign or malignant. The most common mass near the interatrial septum is lipomatous atrial septal hypertrophy (LASH). LASH can be present in patients with intracardiac malignancies, myxomas, lipomas, or other cardiac masses. It is important to recognize the transesophageal echocardiography (TEE) characteristics of these pathologies to arrive at an accurate diagnosis with an appropriate plan for intraoperative resection. At the authors’ institution, patients have been referred for surgery due to a finding of significant LASH masquerading as a left atrial myxoma. In challenging cases, TEE offers a thorough evaluation of the interatrial septum to delineate between multiple intracardiac masses.     

Two-dimensional echocardiographic demonstration of left atrial thrombi in patients with prosthetic mitral valves.

Although M-mode echocardiography (MME) is not a reliable method for detecting left atrial thrombi, recent reports suggest that two-dimensional echo (2DE) may be more effective than MME in identifying intracardiac thrombi. In three patients with prosthetic mitral valves who presented with either arterial embolization or prosthetic valvular dysfunction, 2DE demonstrated left atrial masses consistent with thrombi, while MME was either negative (two patients) or suspicious (one patient) for left atrial thrombus. Thrombi were documented by surgical or postmortem examination in all cases. Clear delineation of the atrial cavity and the margins of the masses, visualization on multiple echocardiographic views and comparison of serial examinations were helpful in identifying these masses as thrombi. In addition, the masses visualized had certain patterns of motion which seem unique and may allow characterization of atrial masses as thrombi.     

Multiple left ventricular thrombi in a patient with left ventricular noncompaction

The major clinical features of myocardial noncompaction are heart failure, arrhythmias, and thromboembolic events. Prominent myocardial trabeculae and deep recesses characteristic of myocardial noncompaction can cause stagnant blood flow and the formation of left ventricular clots. We describe the case of a 62-year-old woman who presented with symptoms of heart failure secondary to left ventricular noncompaction. Transthoracic and transesophageal echocardiography revealed multiple left ventricular thrombi, which had formed despite the patient's long-term therapy with aspirin.Anticoagulative therapy should be considered for patients with myocardial noncompaction who also have risk factors for thromboembolism, such as atrial fibrillation, a history of systemic embolism, or severe left ventricular systolic dysfunction. However, chronic antiplatelet therapy may not sufficiently prevent clot formation in patients who have myocardial noncompaction and severe left ventricular systolic dysfunction.     

Comparative recognition of left ventricular thrombi by echocardiography and cineangiography

Studies performed in 47 patients, 11 of whom underwent surgery for aneurysmectomy and 36 of whom underwent cardiac transplantation, were reviewed to assess the diagnostic accuracies of cross sectional echocardiography and cineangiography in detecting left ventricular mural thrombi and the effect of anticoagulation treatment on the incidence of such thrombi. Cross sectional echocardiography in 37 patients and cineangiography in 26 (16 patients were examined by both methods) were analysed independently by sets of two observers experienced in the respective methods. All four observers were blinded to the pathological or surgical findings regarding mural thrombus. Mural thrombus was confirmed by pathological investigation in 14 of 47 (30%) cases; 11 of these 14 patients had intra-aneurysmal thrombi. The negative predictive value was quite good for both methods, but cross sectional echocardiography had a superior positive predictive value. This was due both to detailed soft tissue resolution by cross sectional echocardiography and to overdetection of mural thrombi by cineangiography in cases of aneurysms without mural thrombi. Mural thrombi were present in three of 20 patients with preceding anticoagulation and in 10 of 19 patients without anticoagulation. The results emphasise that cross sectional echocardiography is more reliable than cineangiography in recognising thrombi.