Role of transesophageal echocardiography in the assessment and therapeutic management of patients with acute ischemic cerebral events before the age of 65

IntroductionIschemic stroke is the leading cause of mortality in Portugal, with around 30 to 50 % of cases being of cardioembolic etiology. Transesophageal echocardiography (TEE) has assumed growing importance in the detection of cardiac sources of embolism. However, there is controversy regarding the implications of TEE findings for the therapeutic approach to patients with ischemic stroke.ObjectivesTo analyze TEE findings in the diagnostic work-up of patients with ischemic cerebral events and to determine their influence on therapeutic strategy.MethodsWe retrospectively studied patients with stroke or transient ischemic attack (TIA) before the age of 65, of no apparent cause after carotid ultrasound, electrocardiogram and transthoracic echocardiography, who underwent TEE between 1992 and 2009. The following diagnoses on TEE were considered as potential embolic sources: atrial septal defect; patent foramen ovale (PFO); atrial septal aneurysm (ASA); vegetations; tumors; intracavitary thrombi; and aortic plaques >2 mm (ascending aorta and arch).ResultsWe analyzed 294 patients, mean age 45 years, 56.8 % men. TEE revealed a potential cardioembolic source in 36.7 % of the patients, PFO and ASA being the most frequent. Throughout the period considered, there was an increase in the number of exams performed, as well as in diagnoses, mainly PFO and ASA. Comparison of patients with and without a diagnosis on TEE showed that the former were older and were more often prescribed oral anticoagulation. By multivariate analysis, the presence of a positive TEE finding was shown to be an independent predictor of treatment with oral anticoagulation (OR=2.48; CI 95%: 1.42–4.34; p=0.001).ConclusionIn the population under analysis, TEE was useful in identifying potential cardioembolic sources and infl uenced the therapeutic strategy.     

Identifying a cardiac source of embolism by transesophageal echocardiography: review of a 12-year experience.

INTRODUCTION: Peripheral embolism is frequently related to a cardiac source of embolism. Transesophageal echocardiography (TEE) is a useful tool for identifying such sources. OBJECTIVES: Our laboratory has gained wide experience in TEE, with a large number of exams performed to search for a cardiac source of embolism. We therefore thought it would be useful to present our experience in the last 12 years following the introduction of the technique. METHODS: This was a retrospective study of 1110 consecutive patients undergoing TEE to search for a cardiac source of embolism, after an embolic event and a transthoracic echocardiogram. RESULTS: The patients' mean age was 53 +/- 14 years, 52% male. There was peripheral embolism in 5% of cases and cerebral embolism in the remainder. The exam identified a potential embolic source in 35.6% of cases, the most frequent diagnoses being intracardiac shunt at the atrial level (9.5%), atrial septal aneurysm (ASA) (6.6%), intracardiac thrombi (6.4%) and atherosclerotic plaques in the thoracic aorta (9.6%). The presence of ASA was frequently associated with patent foramen ovale (27%), which was more frequent in younger patients. Overall, we identified a cardiac source of embolism more often in elderly patients, with a predominance of atherosclerotic plaques in the aorta. ETE was more frequently diagnostic in patients with peripheral embolism, but there were no differences in terms of etiology. CONCLUSIONS: TEE is very useful to search for cardiac sources of embolism, especially in younger patients, in whom causes potentially treatable surgically or percutaneously can be identified. In elderly patients, therapeutic strategy will probably not be changed by the findings (mostly thrombi and atherosclerotic plaques). The presence of ASA and embolic events makes it essential to perform a thorough search by TEE for intracardiac shunts, which are frequently associated.     

Racial differences in the prevalence of cardiac sources of embolism in subjects with unexplained stroke or transient ischemic attack evaluated by transesophageal echocardiography

Little is known about the distribution of cardiac sources of embolism among African-Americans with cryptogenic cerebrovascular events. We compared the prevalence of potential cardiac sources of embolism between black and white patients referred to our laboratory for transesophageal echocardiographic (TEE) evaluation of unexplained stroke or transient ischemic attack. Records were reviewed to exclude subjects with high-risk cardiac or vascular disorders likely to explain the index event. Of 297 patients satisfying the inclusion criteria, 196 were white and 87 black. Potential cardioembolic sources were significantly less common in blacks than in whites (adjusted odds ratio [OR], 0.44; 95% confidence interval [CI] 0.26 to 0.75), and related largely to the difference in prevalence of interatrial communication (OR 0.40; 95% CI 0.21 to 0.74). In contrast, African-Americans had a higher prevalence of left ventricular (LV) hypertrophy (OR 3.50; 95% CI 1.97 to 6.22), and particularly, moderate or severe hypertrophy (OR 4.03; 95% CI 1.88 to 9.65) compared with whites. In conclusion, in African-Americans with unexplained cerebrovascular events, the yield of TEE for potential cardioembolic sources, and especially interatrial communication, is lower than in their white counterparts. African-Americans exhibit a substantially higher prevalence of LV hypertrophy, which may be a marker for a higher burden of subclinical cerebrovascular disease involved in the pathogenesis of cryptogenic cerebral ischemia in this population.     

Role of Echocardiography in Assessment of Cardioembolic Sources: a Strong Diagnostic Resource in Patients with Ischemic Stroke

Purpose of Review

This review will discuss the most frequent sources of cardiac embolism and the role of echocardiography in these different clinical settings, and, in addition, provide suggestions about the choice between transthoracic (TTE) and transesophageal echocardiography (TEE).

Recent Findings

Stroke is the third leading cause of death in industrial countries, and 15–40% of all ischemic strokes are due to cardioembolism. TTE and TEE are cornerstones in the detection of cardioembolic sources and provide fundamental information about the embolic risk and most suitable treatment of these patients, improving long-term outcomes.

Summary

Echocardiography is a widely available, inexpensive, and safe diagnostic tool that is almost free from contraindication, and these elements allow the common use of this technique in almost all the patients with ischemic stroke. The most common cardioembolic sources include left atrial appendage thrombosis during atrial fibrillation; vegetations in infective endocarditis; cardiac masses including left ventricular thrombosis, cardiac tumors, etc.; atherosclerotic plaques; and passageways within the heart serving as conduits for paradoxical embolization, e.g., patent foramen ovale.

     

Atheromatous disease of the thoracic aorta and systemic embolism. Clinical picture and therapeutic challenge

Systemic embolism is a frequent cause of stroke. At the beginning of the last decade by introduction of transesophageal echocardiography and other imaging techniques atheromatosis of the aortic arch has been recognized as an important source of embolism. Formerly in the pre-TEE era, this entity was included into cryptogenic strokes. Aortic atheromas are found in about one quarter of patients presenting with embolic events. The severity of atherosclerosis graded by TEE correlates with the risk for future embolism, especially if mobile lesions or superimposed thrombi are present. Independent of plaque extension, patients with unstable plaques characterized by echo-lucency, inhomogenity, lacking of calcifications, ulceration, mobile parts and concomitant spontaneous echo contrast within the aorta have a higher risk for embolic events. However, the diagnosis of aortic atheromatosis is mostly established if an embolic event has already occurred. Therefore, it is important to identify patients at risk, especially before they undergo interventions with manipulation at the aorta like coronary bypass surgery. Risk factors are age above 70, diabetes mellitus, hyperlipidemia, arterial hypertension, aortic calcifications on standard chest X-ray, elevated serum levels of C-reactive protein, other inflammatory markers, and an activated coagulation. Randomized studies for treatment of patients with severe aortic atheromatosis are not yet existing. Warfarin has been shown to prevent stroke in patients with mobile atheromas and superimposed thrombi, but there are case reports about aggravation of cholesterol embolism under warfarin treatment. It is concluded from other atherosclerotic manifestations that plaque stabilizing treatment with statins and ACE inhibitors is also beneficial.     

Yield of transesophageal echocardiography for nonbacterial thrombotic endocarditis and other cardiac sources of embolism in cancer patients with cerebral ischemia

Cerebrovascular events occur frequently in patients who succumb to cancer, and nonbacterial thrombotic endocarditis (NBTE) is a frequent postmortem finding in these patients. Despite the excellent diagnostic accuracy of transesophageal echocardiography (TEE) for cardiac sources of cerebral embolism, however, the prevalence of NBTE and other cardioembolic sources in patients with cancer and cerebral ischemia has not been investigated using this modality. This study examined the frequency of cardioembolic findings in consecutive patients with cancer referred to our institution for TEE evaluation of cerebrovascular events. The study cohort comprised 51 patients, of whom 18% had marantic vegetations, and 47% and 55% of whom had definite and definite or probable cardiac sources of embolism, respectively. The present study documents, for the first time, a high frequency of marantic endocarditis and other cardioembolic sources in patients with cancer and cerebrovascular events selected for TEE. This finding has important implications for evaluation and management in this patient population.     

A left atrial thrombus is not an absolute limitation to balloon mitral commissurotomy for patients with mitral stenosis. a serial transesophageal echocardiographic study

Previous reports did not encourage balloon mitral commissurotomy (BMC) when left atrial (LA) thrombi were located beyond LA appendage. We hypothesize that LA thrombi may be resolved in some patients after anticoagulant therapy, and BMC can be performed subsequently. In the present study, we used transesophageal echocardiography (TEE) to evaluate the effects of anticoagulant on LA thrombi in patients with mitral stenosis, to compare the clinical differences between patients with (group A) and without (group B) resolution of LA thrombi, and to evaluate the safety of subsequent BMC in these patients. TEE was performed on 190 consecutive patients with mitral stenosis; 14 (7.4%) of them were found with LA thrombi. Serial TEE was performed and optimal anticoagulant therapy was achieved in all 14 patients. The thrombi were located within the LA appendage in 6 cases, attached to the LA posterior wall in 5, posterior wall and interatrial septum in 1, and LA appendage and posterior wall in 2. Based on the 6-month TEE follow-up, we found that the LA thrombi disappeared in 8 (57.2%) patients (group A) and persisted in 6 patients (group B). LA thrombi resolved within 3 months in 7 group A patients (87.5%). Furthermore, the resolution of LA thrombi was more frequently observed in patients either with a smaller LA dimension (51.9 +/- 3.4 vs. 57.8 +/- 4.8 mm, p = 0.02) or with their thrombi located inside their LA appendage (p = 0.03). No differences in other clinical and echocardiographic variables were noted between these two groups. Subsequently, group A patients underwent BMC without complications of systemic embolization. In conclusion, LA thrombi can be resolved after optimal anticoagulant therapy in a considerable proportion of patients with mitral stenosis. Serial TEE studies are helpful to observe LA thrombus resolution; they may also be useful in planning the treatment strategy.     

Atrial thrombi-a prospective follow-up study over 3 years with transesophageal echocardiography and cranial magnetic resonance imaging

BACKGROUND: Patients with atrial fibrillation (AF) and atrial thrombi have an increased risk for cerebral embolism. However, there is little knowledge about the long-term fate of atrial thrombi and the incidence of cerebral embolism in patients under oral anticoagulation. METHODS: Consecutive patients with persistent or permanent AF and left atrial (LA) thrombi were included in the study. We performed serial and prospective transesophageal echocardiography, cranial magnetic resonance imaging, and clinical examinations during a period of 3 years. Oral anticoagulation was continued or initiated in all patients. A target INR of 2.5 was intended in all patients. RESULTS: Forty-three patients with LA thrombi and persistent or permanent AF were included. During the follow-up period 31(72%) of the thrombi disappeared. Patients with disappearance of thrombi had significantly smaller thrombi (P < 0.01), a lower echogenicity of thrombi (P < 0.01), and a lower LA volume (P = 0.02). Twenty-two (51%) patients suffered from cerebral embolism and/or death during the observation period. Five patients died due to embolic events. The only independent predictors of cerebral embolism were an elevated peak emptying velocity of the LA appendage (P < 0.001) and a history of previous thromboembolism (P < 0.01). CONCLUSIONS: Patients with persistent or permanent AF and atrial thrombi have a high long-term risk of cerebral embolism and/or death (51%) even despite the oral anticoagulation therapy. Thrombus size may predict thrombus resolution under continued anticoagulation.     

Aortic atherosclerotic plaques as a source of systemic embolism

Objectives. Our study was designed to determine the significance of aortogenic embolism in an unselected autopsy collective.Background. Although embolism arising from atherosclerotic plaques in the aorta has been acknowledged, the role of aortic atheromatosis among other well known sources of embolism remains to be further clarified.Methods. We examined the proximal part of the arterial system with regard to the presence of atherosclerotic lesions as well as cardiac changes in 120 consecutive necropsy studies. Pathologic evidence of embolic events was recorded. Clinical and neuropathologic data were also surveyed in all patients.Results. Among atherosclerotic lesions, fibrous plaques (p < 0.05) and calcified (p < 0.0001) and ulcerated lesions (p < 0.0001) as well as thrombi (p < 0.005) were observed significantly more frequently in the aortic arch and in the descending aorta than in the ascending aorta, whereas fatty streaks were distributed uniformly. In 40 (33%) of the 120 patients, we found pathologic evidence of arterial embolization. Multiple logistic regression analysis revealed a significant correlation between embolism and complicated atherosclerotic plaques in the aortic arch (odds ratio [OR] 5.8, 95% confidence interval [Cl] 1.1 to 31.7, p < 0.05), severe ipsilateral carotid artery disease (OR 3.1, 95% CI 3.1 to 45.3, p < 0.001) and atrial fibrillation (OR 3.5, 95% CI 1.1 to 9.9, p < 0.05).Conclusions. Complicated atherosclerotic plaques in the aortic arch represent an independent risk factor for systemic embolism similar to atrial fibrillation and severe atherosclerosis of the carotid arteries.     

Incidence and Predictors of Left Atrial Thrombus Prior to Catheter Ablation of Atrial Fibrillation

Background: Transesophageal echocardiography (TEE) is commonly used prior to catheter ablation of atrial fibrillation (AF) in order to exclude left atrial (LA) thrombus. However, the incidence and predictors of LA thrombus detected with TEE have not been systematically examined in this setting.
Methods: This study included 732 cases (mean age 57 ± 11 years; 23% female; 353 persistent AF) in 585 consecutive patients referred for catheter ablation of AF. Patients were anticoagulated for at least 4 weeks prior to the procedure and then bridged with enoxaparin. TEE was performed in all cases within 24 hours prior to ablation.
Results: Preprocedural TEE revealed LA thrombus in 12 of 732 cases (1.6%), all located in the LA appendage. Among these 12 patients, 9 had persistent AF and 3 had paroxysmal AF. All patients with thrombus had an LA size ≥ 4.5 cm. LA thrombus was present in 0.3%, 1.4%, and 5.3% of patients with CHADS₂ scores of 0, 1, and ≥ 2, respectively. In multivariate analysis, a CHADS₂ score ≥ 2 and larger LA diameter remained significant predictors of LA thrombus.
Conclusions: Despite oral anticoagulation treatment, there is a small but significant incidence of LA thrombus by TEE prior to AF ablation. A CHADS₂ score ≥ 2 and larger LA diameter are independent predictors of LA thrombus in this patient population, while type of AF or rhythm at the time of TEE is not. The risk of LA thrombus is low in patients with a CHADS₂ score of 0 and in patients with an LA diameter < 4.5 cm.     

A transesophageal echocardiographic study on risk factors for stroke in elderly patients with atrial fibrillation: a comparison with younger patients

STUDY OBJECTIVES: Atrial fibrillation (AF) becomes an increasingly important cause of stroke as patients get older. The aim of the study was to determine whether risk factors of cerebral embolism among elderly patients with AF differed from those of younger patients by using transesophageal echocardiography (TEE). Design and setting: Cross-sectional study at a university hospital. METHODS: Cardiovascular lesions with the potential for thromboembolism in patients with AF were investigated using TEE. Left atrial spontaneous echocardiographic contrast (SEC), peak flow velocity in the left atrial appendage (LAA-flow), and aortic atherosclerosis of the thoracic aorta were assessed in 67 elderly (> or = 70 years old) and 135 younger (< 70 years old) patients. All patients underwent either brain CT (n = 54) or MRI (n = 148) to assess presence of cerebral infarction. RESULTS: Cerebral infarction due to embolism was noted in 113 patients with AF. There was a higher prevalence of cerebral embolism in elderly patients when compared with younger patients (78% vs 45%; p < 0.001). Cerebral embolism found in younger patients was associated with high grade of SEC and lower LAA-flow (p < 0.05). In addition to these TEE findings, aortic atherosclerosis was more severe in elderly patients with cerebral embolism than in those without cerebral embolism (p < 0.0001). By multivariate logistic analysis, LAA-flow was an independent predictor of cortical infarction in younger patients, but not in elderly patients, whereas aortic atherosclerosis was a useful marker in predicting embolic risk in elderly patients. CONCLUSIONS: TEE findings indicative of left atrial blood stasis were useful to identify the embolic risk of younger patients with AF, while atherosclerosis of the thoracic aorta appears to be an important marker for cerebral embolism in elderly patients.     

The frequency and significance of coronary arterial thrombi and other observations in fatal acute myocardial infarction: a study of 107 necropsy patients

Observations made from histologie study of the entire extramural coronary arterial tree are described in 107 patients who died of acute ischemie heart disease: seventy-four had transmural left ventricular myocardial infarction, nine had necrosis limited to the inner one half of the left ventricular myocardium (acute subendocardial infarcts) and twenty-four died suddenly (less than six hours from onset of symptoms of myocardial ischemia) without histologically detectable myocardial necrosis. Old atherosclerotic plaquing was diffuse and extensive in the extramural coronary arteries in 104 of the 107 patients. The lumens of at least two of the three major extramural coronary arteries (right, left anterior descending and left circumflex) were narrowed more than 75 per cent by old atherosclerotic plaques in 101 of the 107 patients.Coronary arterial thrombi were found in forty (54 per cent) of the seventy-four patients with transmural necrosis, in none of the nine with only subendocardial necrosis and in two (8 per cent) of the twenty-four who died suddenly. In thirty-seven of the forty-two patients with antemortem coronary arterial clots the lumen of the vessel containing the thrombus was already narrowed more than 75 per cent by old atherosclerotic plaques at or distal to the thrombus. The infrequency of coronary thrombi in patients who died of acute cardiovascular collapse without myocardial necrosis, in those in whom necrosis was limited to the subendocardium, in those who died without cardiogenic shock or congestive cardiac failure, and their occurrence at, or proximal to, sites already severely narrowed by old atherosclerotic plaques suggest that coronary thrombi are consequences rather than causes of acute myocardial infarction. The occurrence of components of thrombi, i.e., fibrin and platelets, in old atherosclerotic plaques and the finding of components of old atherosclerotic plaques, i.e., foam cells, cholesterol clefts, pultaceous debris and calcific deposits, in known thrombi (for example, those located in the left atrium of patients with mitral stenosis) strongly suggest, however, that old atherosclerotic plaques are derived, at least in part, from organization of thrombi.     

Thromboembolic risk in atrial flutter. The FLASIEC (FLutter Atriale Società Italiana di Ecografia Cardiovascolare) multicentre study.

AIMS: Patients with atrial flutter are believed to be at lower risk of thromboembolism than patients with atrial fibrillation. However, the incidence of atrial thrombi and the need for anticoagulation in patients with atrial flutter is not well established. METHODS AND RESULTS: A prospective observational multicentre study was undertaken to assess the frequency of atrial thrombi and spontaneous echocontrast and the prevalence for aortic complex atherosclerotic lesions in a cohort of unselected patients with atrial flutter. We evaluated 134 patients (102 male, aged 70+/-9 years); exclusion criteria were history of atrial fibrillation, rheumatic mitral valve disease and mitral mechanical prosthesis. The median of atrial flutter duration was 33 days. Twelve patients had been taking warfarin for more than 7 days. One hundred and twenty-four patients (94%) underwent a transoesophageal echocardiogram, which revealed left atrial appendage thrombi in two patients (1.6%) and right atrial thrombi in one patient (1%). At least moderate left atrial echocontrast was found in 16/124 patients (13%). Complex atherosclerotic aortic plaques were detected in 10 patients (8%). Atrial flutter conversion was attempted in 93/134 patients (69%). At the 1-month follow-up, two patients experienced a thromboembolic event following restoration of sinus rhythm. CONCLUSIONS: Atrial thrombi and echocontrast, and complex aortic atherosclerotic plaques are relatively uncommon in patients with atrial flutter. Post-cardioversion embolism was observed in two patients in our study population.     

Cardiological diagnosis in arterial embolism]

Potential cardiac sources of arterial embolism are in particular thrombi within the left atrium or ventricle, or attached to a prosthetic valve, intracardiac tumors, and vegetations due to endocarditis. Patent foramen ovale and atrial septal defect may lead to paradoxical embolism, and spontaneous echo contrast within the heart has to be considered as a parameter of increased thromboembolic risk. In rare cases, atrial septal aneurysm, mitral valve prolapse or annulus calcification and calcified aortic stenosis has to be taken into consideration. Current method of choice for diagnosis of these abnormalities is echocardiography. When the transthoracic approach fails, transesophageal echocardiography (TEE) leads to a definite diagnosis in most cases. Precordial echocardiography allows the detection of left ventricular thrombi with a sensitivity ranging between 72 and 95%, and monoplane TEE does usually not increase these numbers. In contrast, thrombi within the left atrium and particularly in the left atrial appendage can be detected with a significantly higher detection rate when TEE is used. The same is true for spontaneous echo contrast in the left atrium, a phenomenon which is almost exclusively diagnosed by TEE, as well as for endocarditis associated vegetations that can be identified by TEE with a sensitivity higher than 90%. Patient foramen ovale is usually diagnosed by precordial contrast echocardiography combined with a Valsalva maneuver; color Doppler or contrast TEE allows to increase the detection rate. In the diagnosis of prosthetic valve attached thrombi and vegetations, TEE is clearly superior compared to the precordial examination, at least concerning prosthetic devices in mitral position. If echocardiography fails to identify a potential cardiac source of embolism, other techniques don't add significant information in most cases. Detection of a potential source of embolism, however, does not necessarily prove that the particular finding represents the true etiology of an embolic event; results of all clinical and technical examinations have to be evaluated in a critical synopsis. In addition, proper therapeutic consequences in quite a number of abnormalities considered as potential cardiac sources of embolism are not yet defined.     

Frequency of interatrial block in patients with sinus rhythm hospitalized for stroke and comparison to those without interatrial block

Interatrial block (IAB; P wave > or =110 ms) is a potent correlate of left atrial (LA) enlargement and electromechanical dysfunction and a strong predictor of atrial tachyarrhythmias, in particular, atrial fibrillation. Although these associations increase its risk for embolism, i.e., cardioembolic stroke, such a phenomenon has been inadequately investigated. We investigated 85 general hospital patients who had been admitted to the neurologic unit between January 2003 and December 2004 for embolic stroke. Of those, 66 patients who had electrocardiograms that showed sinus rhythm were evaluated for IAB and categorized as those with IAB and those without (controls). Medical records were then reviewed for common co-morbidities and stroke risk factors, high-resolution carotid artery Doppler ultrasonographic study reports, and 2-dimensional echocardiograms obtained during the current admission for embolic stroke; 40 patients (61%) had IAB. There was a 55% prevalence of LA enlargement (diameter in the parasternal long-axis view > or =40 mm, p <0.001). LA thrombi and/or spontaneous contrast ("smoke") were noted on echocardiograms in 6 patients with IAB (15%) but not in any of the controls (p = 0.038). Five of those 6 patients with such LA thrombi had dilated LA cavities. In conclusion, IAB could be a risk for embolic stroke due to its known sequelae of LA dilation and electromechanical dysfunction that predispose to thrombosis. If prospective studies prove this to be so, the need for anticoagulation use in such patients should be investigated.     

Feasibility and clinical utility of transesophageal echocardiography in the acute phase of cerebral ischemia

We evaluated the feasibility and clinical utility of transesophageal echocardiography (TEE) in the early management of ischemic stroke. TEE was performed in consecutive patients with acute cerebral ischemia within 48 hours of symptoms onset. The data were analyzed by age (<55 vs ≥55 years), and the baseline stroke etiology was classified (determined vs undetermined). TEE was feasible in 660 (61%) of 1,080 patients. Left atrial abnormalities and complicated aortic plaques prevailed in older patients (p <0.05), irrespective of the stroke etiology. A patent foramen ovale prevailed in younger patients (p <0.05) but even in older patients was present in 13% of the determined and 31% of the undetermined stroke subgroups. Overall, high-risk and potentially high-risk cardioembolic sources were detected in 47% of the patients, and stroke etiology was consequently reviewed: 40% of the baseline undetermined strokes were reclassified as cardioembolic, and 29% of lacunar, 42% of large artery, and 30% of other determined-cause strokes were reclassified as concurrent etiology. Subsequently, according to the current guidelines, 12% of patients were reassigned from antiplatelet to anticoagulant therapy and 17% of patients were treated with high-dose statins; overall, secondary prevention treatment was modified in 26% of patients. In conclusion, TEE was feasible in about 2/3 of the patients investigated within 48 hours of the index event, contributed to stroke classification in 1/3 of cases, and guided secondary prevention therapy in 1/4 of patients. Therefore, TEE is useful for defining patients' risk profile for stroke recurrence.     

Transesophageal Echocardiography for the Prevention of Embolic Complications After Catheter Ablation for Atrial Fibrillation

Background: Thromboembolic complications during left-sided ablations range between 1.5 and 5.4%. Preprocedural TEE has been used to exclude the presence of left atrial thrombi in order to minimize risk. The use of TEE is empiric and it has not been evaluated in contemporary practice.
Methods and Results: A multicenter national survey describing the practice at 11 Canadian teaching hospitals. A total of 2,225 patients underwent elective catheter ablation for symptomatic AF. Transesophageal echocardiography (TEE) was used either routinely or selectively as a preablative strategy in patients. There were 996 patients in a routine preprocedure TEE strategy and 1,190 in a selected TEE strategy; 1 center (n = 39 patients) did not perform TEE. Twelve of 996 (1.2%) in the routine unselected cohort had thrombi identified. TEEs were performed in 200 of 1,190 in the selected cohort; 4 (2.0%) left atrial thrombi were observed; there was no significant difference in the prevalence of thrombi (P = 0.34). A total of 11 embolic events occurred inclusive of all groups. There was no difference in event rates between the 2 strategies (0.6% and 0.4%, P = 0.54). Events were unrelated to AF duration (persistent vs paroxysmal, r = 0.03, N = 2,225, P = 0.9).
Conclusion: The selection criteria employed to perform TEEs did not increase the chance of identifying LA thrombi in a patient cohort with primarily nondilated left atria and paroxysmal AF. The overall thromboembolic event rate was low (0.49%) and was not significantly different between the 2 TEE strategies.     

Value of transesophageal echocardiography,esophago-gastroduodenoscopy and retinoscopy prior to intra-arterial fibrinolytic therapy in patients with peripheral arterial disease

BACKGROUND: We prospectively investigated the need for esophagogastroduodenoscopy (EGD), transesophageal echocardiography (TEE) and retinoscopy for pre-interventional screening in patients with peripheral arterial occlusive disease (PAD) prior to intraarterial fibrinolytic therapy. PATIENTS AND METHODS: 212 consecutive patients suffering from PAD (164 male and 48 female, mean age: 64 +/- 11 years, 161 patients stage II of Fontaine's classification, 10 patients at stage III and 41 patients at stage IV) referred for interventional treatment were included. 173 EGDs, 169 TEEs and 188 retinoscopies were performed within one week prior to fibrinolysis. 114 patients had all three examinations. RESULTS: Pathologic findings were detected in 56 (49%) of the 114 patients: 23 erosions, 12 ulcers, 2 esophagites, 1 gastric carcinomata, 3 intracardiac thrombi, 5 aortic thrombi, 11 diabetic and 5 hypertensive retinopathies and 1 with retinal aneurysms. 30 patients (25%) received fibrinolytic therapy, despite a contraindication: The one patient with ventricular thrombus was treated as an ultimate therapy, and amputation was prevented. Two patients showing plaques covered by large thrombi in the descending thoracic aorta were treated because cranial embolism should not occur. Four diabetic patients with multilevel disease, severe claudication and prior retinal bleeding were treated. Fibrinolytic therapy was started on 23 patients after complete healing of the mucosal lesions. CONCLUSION: TEE revealed potential sources of embolization in 4% of the patients and is justified to reduce the individual risk. Retinoscopy should be done in patients with diabetes mellitus and hypertension, and if prior bleeding is present fibrinolysis should be done only if other treatment-regimes are not available.     

Comparison of contrast enhanced 64-slice computed tomography and transesophageal echocardiography in detection of left atrial thrombus in patients with atrial fibrillation

BACKGROUND AND OBJECTIVE: Recent advances in multi-slice computed tomography (MSCT) have allowed an improved analysis of left atrial (LA) and left atrial appendage (LAA) anatomy prior to catheter ablation of atrial fibrillation (AF). However, data regarding the ability of MSCT to identify LA/LAA thrombus are limited. This prospective study compared the efficacy of 64-slice contrast-enhanced computed tomography (64CCT) with transesophageal echocardiography (TEE) of the heart in the identification of LA/LAA thrombus. MATERIALS AND METHODS: One-hundred and seventy consecutive patients scheduled for first-time catheter ablation of paroxysmal (n = 120) or persistent (n = 50) AF were enrolled for study. Each patient underwent non-gated 64CCT and TEE of the heart for exclusion of LA/LAA thrombus prior to ablation procedure. RESULTS: Fourteen cases (8.2%) of LA/LAA thrombi were interpreted by 64CCT (ten false-positive, four true positive), whereas 11 actual thrombi (6.5%) were detected by TEE (seven false-negative by 64CCT) in the same population. Maximal dimension of TEE identified thrombi did not differ between the false-negative by 64CCT group and the true-positive group (17 +/- 6 vs. 18 +/- 5 mm P = 0.677). Results indicated 64CCT sensitivity = 36.4%, specificity = 93.7%, positive predictive value = 28.6%, and negative predictive value = 95.5% in the detection of LA/LAA thrombus. The Kappa value in evaluating the agreement between 64CCT and TEE for detection of LA/LAA thrombus was 0.267. CONCLUSION: Compared to gold standard TEE, 64CCT was shown to be less reliable in the detection of LA/LAA thrombus prior to catheter ablation in patients with AF.     

Comparison of Echocardiographic Markers of Embolism in Atrial Flutter and Fibrillation: Frequency of Protruding Atherosclerotic Plaques in the Thoracic Aorta

The potential additional embolic risk of protruding aortic plaques ≥ 4 mm and left atrial abnormalities such as thrombus, spontaneous echocardiographic contrast (SEC), low left atrial appendage velocity, recently has been shown in patients with atrial fibrillation (AF). However, the presence and potential role of transesophageal echocardiographic (TEE)‐detected protruding aortic plaques ≥ 4 mm have not been systematically evaluated in patients with atrial flutter. Among 2493 patients evaluated by TEE, 271 consecutive patients with atrial flutter (n = 41 ) and AF (n = 230 ) ≥ 2 days duration were included in the study. Clinical and echocardiographic characteristics in consecutive patients with atrial flutter were compared to those in patients with AF, especially atrial morphology and function and atherosclerotic disease of the thoracic aorta. Clinical characteristics of patients with atrial flutter and AF were similar with regard to age (68 ± 13 and 67 ± 12, P = 0.628 ), sex ratio (men, 66% and 54%, P = 0.212 ), and previous embolic events (5% and 15%, P = 0.126 ), respectively. The frequency of protruding atherosclerotic plaques ≥ 4 mm (12% and 11%, P = 0.919 ) and SEC (15% and 14%, P = 0.847 ) in the thoracic aorta was similar in patients with atrial flutter and AF. Left atrial appendage area was smaller (3.1 ± 0.7 and 6.0 ± 3.0 cm², P = 0.001 ), left atrial appendage SEC was less frequent (17% and 37%, P = 0.024 ), and left atrial appendage emptying velocity was higher (47 ± 10 and 30 ± 10 cm/s, P = 0.030 ) in patients with atrial flutter as compared to those with AF. There was no difference between the two groups regarding left ventricular fractional shortening (30 ± 10% and 33 ± 13%, P = 0.630 ), rheumatic valvular disease (5% and 12%, P = 0.301 ), left atrial diameter (43 ± 7 and 45 ± 8 mm, P = 0.134 ), right atrial area (16 ± 4 and 17 ± 6 cm², P = 0.384 ), left atrial SEC (39% and 53%, P = 0.124 ), or atrial thrombus (2% and 3%, P = 0.888 ) respectively. Our results point to the high prevalence of protruding atherosclerotic plaques in the thoracic aorta in patients with atrial flutter.