Relation of transesophageal echocardiographic findings to subtypes of cerebral infarction in patients with atrial fibrillation

BACKGROUND: Transesophageal echocardiography (TEE) has been used to identify the potential risk for cardiogenic embolism in patients with atrial fibrillation (AF). However, ischemic stroke in patients with AF is not always attributable to embolism. Identification of the risk of embolic versus atherothrombotic stroke should lead to the optimal individualized management of patients with AF. HYPOTHESIS: The goal of the study was to determine the relation between cortical infarction and perforating infarction and TEE findings in patients with AF. METHODS: We investigated the clinical usefulness of TEE in the risk stratification of clinical subtyping of the cerebral infarctions which were divided into two territories of the cortical branch (cortical infarction due to embolism) and deep perforators (perforating infarction due to atherothrombosis). Left atrial spontaneous echo contrast, peak flow velocity in the left atrial appendage, and generalized atherosclerosis as estimated by the intima-media wall thickness of the thoracic aorta were assessed by TEE in 118 consecutive patients with either paroxysmal (n = 44) or chronic (n = 74) AF. All patients underwent either brain computed tomography or magnetic resonance imaging. RESULTS: Cortical and perforating infarction was found in 39 and 18% of patients, respectively. The grade of spontaneous echo contrast was higher in patients with than in those without cortical infarction (p < 0.05). In contrast, patients with perforating infarction showed significant increase in the aortic wall thickness when compared with patients without perforating infarction (p < 0.05). In addition, multivariate logistic analysis revealed that spontaneous echo contrast was an independent predictor of cortical infarction, while intima-media wall thickness of the aorta, hypertension, and age were useful in predicting the risk of perforating infarction. CONCLUSIONS: Transesophageal echocardiography has a potential role in the risk stratification for cortical and perforating infarction in patients with AF.     

Aortic spontaneous echocardiographic contrast and hemostatic markers in patients with nonrheumatic atrial fibrillation

OBJECTIVES: To determine the relationship between spontaneous echocardiographic contrast (SEC) in the descending thoracic aorta and plasma levels of hemostatic markers in patients with nonrheumatic atrial fibrillation (AF). DESIGN AND SETTINGS: A cross-sectional study at a university hospital. PATIENTS AND MEASUREMENTS: In 91 consecutive patients (mean +/- SE age, 70 +/- 1 years; 68 men) with nonrheumatic AF who underwent transesophageal echocardiography, plasma levels of markers for platelet activity (platelet factor 4 [PF4] and beta-thromboglobulin [beta-TG]), thrombotic status (thrombin-antithrombin III complex [TAT]), and fibrinolytic status (D-dimer and plasmin-alpha(2)-plasmin inhibitor complex [PIC]) were determined. RESULTS: Forty-three patients who had aortic SEC (AoSEC) were older (72 years vs 68 years; p < 0.05) and had a higher prevalence of chronic AF (88% vs 52%; p < 0.05) than 48 patients without AoSEC. TAT, PIC, and D-dimer levels were significantly higher in patients with AoSEC than in those without AoSEC, whereas PF4 and beta-TG levels were not different between the two groups. Although the prevalence of cerebral embolism did not differ between the two groups (23% vs 29%), the prevalence of peripheral embolism was higher in patients with AoSEC than in those without AoSEC (10% vs 0%; p < 0.05). Multivariate analysis revealed mitral regurgitation (odds ratio, 7.53; p < 0.02), SEC in the left atrium (odds ratio, 2.14; p < 0.02), and aortic atherosclerosis (odds ratio, 1.87; p < 0.04) emerged as independent predictors of AoSEC. CONCLUSIONS: Patients with nonrheumatic AF who have AoSEC appear to have enhanced coagulation activity but not platelet activity. Intensive anticoagulation treatment might be required for these patients.     

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.     

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.     

Silent cerebral infarction in patients with dilated cardiomyopathy: echocardiographic correlates

BACKGROUND: Patients with dilated cardiomyopathy (DCM) have an increased risk of thromboembolic events. Incidence of silent cerebral infarction (SCI) has not been investigated in these patients. The aim of this study was to investigate the incidence of SCI in patients with DCM and to determine its associations with echocardiographic parameters. METHODS AND RESULTS: Seventy-two patients (mean age 62+/-12 years) with DCM underwent cranial magnetic resonance imaging in addition to transthoracic and transesophageal echocardiographic examination. A total of 56 age-matched healthy volunteers served as a control group for comparison SCI prevalence. Prevalence of SCI was significantly higher in patients with DCM (35% vs. 3.6%; p<0.001). In DCM group, patients with SCI had significantly impaired left ventricular systolic function, higher frequency of restrictive diastolic filling, moderate to severe left atrial spontaneous echo contrast (SEC), aortic SEC, and complex atherosclerosis or calcified plaques in the aorta. In logistic regression analysis, type of diastolic filling emerged as the only independent risk factor for SCI (p<0.001). When the type of diastolic filling was removed from the analysis, ejection fraction, marked left atrial SEC, complex-calcified aortic atheroma and age appeared as the other independent risk factors (p = 0.003, p = 0.009, p = 0.013 and p = 0.018, respectively). CONCLUSION: SCI is a frequent finding in DCM patients. Impaired systolic function, restrictive filling pattern, presence of moderate to severe left atrial SEC, and complex atherosclerosis in the aorta are the factors contributing to the development of SCI.     

Transesophageal echocardiography in the diagnosis of diseases of the thoracic aorta: part II-atherosclerotic and traumatic diseases of the aorta

Transesophageal echocardiography (TEE) has provided an accurate new window for the evaluation of diseases of the thoracic aorta. Experience with TEE has led to an increased recognition of atherosclerosis of the thoracic aorta as a source of cerebral and systemic embolism. Certain features of aortic plaque morphology detected by TEE may prove to have prognostic and therapeutic significance. The intraoperative assessment of thoracic aortic atherosclerosis by TEE may guide modifications in surgical techniques and aortic manipulations that reduce the incidence of perioperative neurologic complications. TEE has also become a valuable tool for the diagnostic evaluation of patients with blunt chest trauma. The precise role of TEE in the management of these disorders is currently under investigation.     

Patients with atrial fibrillation and dense spontaneous echo contrast at high risk a prospective and serial follow-up over 12 months with transesophageal echocardiography and cerebral magnetic resonance imaging

OBJECTIVES: We sought to assess the prognosis of patients with atrial fibrillation (AF) and dense spontaneous echo contrast (SEC) and to determine the incidence of cerebral embolism under continued oral anticoagulation. BACKGROUND: Patients with AF and dense SEC have an increased risk of cerebral embolism. However, there is little knowledge about the long-term fate and the rate of clinical silent cerebral embolism under continued oral anticoagulation. METHODS: Between 1998 and 2001, all consecutive patients with AF and dense SEC were included in the study. We performed serial and prospective transesophageal echocardiography, cranial magnetic resonance imaging, and clinical examinations during a period of 12 months. RESULTS: A total of 128 patients with dense SEC and AF were included. The control group consisted of 143 patients with faint SEC and AF. During the follow-up period, three patients (2%) had cerebral embolism with neurologic deficits. A total of eight patients (6%) died due to embolic events, and 19 (15%) patients had silent embolism, as documented on cerebral magnetic resonance imaging. Patients with an event had significantly lower left atrial appendage peak emptying velocities and more commonly had a history of previous thromboembolism and denser SEC, as compared with patients without an event. CONCLUSIONS: Patients with AF and dense SEC have a high likelihood of cerebral embolism (22%) and/or death, despite oral anticoagulation. Low peak emptying velocities of the left atrial appendage and dense SEC are independent predictors of an event.     

Improved detection of spontaneous echo contrast in the aorta with tissue Doppler imaging

AIMS: Spontaneous echo contrast (SEC) within the cardiac chambers has been associated with increased risk of thromboembolism. We investigated the presence and severity of SEC in the aorta with tissue Doppler imaging (TDI) and compared these to the aortic flow velocity and to the clinical profile of the patients. METHODS AND RESULTS: Seventy patients (35 males, 35 females, mean age 64, 22-86 years) underwent TEE for standard indications. Spontaneous echo contrast was studied with conventional and TDI imaging. Aortic flow velocity was measured in the center and lateral part of the descending aorta. SEC of any grade was detected in 24 patients with conventional imaging and in 53 using TDI (P < 0.0001). The presence of swirling was associated with aortic atherosclerosis, older age, history of hypertension and coronary artery disease, atrial fibrillation, and previous embolic events. There was correlation between intraaortic swirling, larger descending aortic diameter (23.6 vs 17 mm, P < 0.00001) and lower peak aortic flow velocity (55 vs 68 cm/s, P = 0.038). CONCLUSION: Spontaneous echo contrast in the aorta is common in high-risk patients and is associated with increased clinical profile, larger aortic diameter, and lower peak aortic flow velocity. Tissue Doppler imaging is more sensitive in the detection of SEC than conventional imaging.     

Atherosclerosis of the aorta in patients with acute thoracic aortic dissection

BACKGROUND: The role of atherosclerosis in thoracic aortic dissection has not been established yet. Transesophageal echocardiography (TEE) is an imaging modality widely used in the diagnostic evaluation of thoracic aortic dissection, and it can detect aortic atherosclerotic plaques and assess their size and specific characteristics. METHODS AND RESULTS: One hundred consecutive patients with thoracic aortic dissection and adequate imaging of the thoracic aorta by TEE were studied. The type of dissection (proximal or distal) and the presence and the degree of aortic atherosclerosis were defined. Proximal aortic dissection (Stanford type A) was found in 64 patients. Patients with proximal dissection were younger than those with distal (type B; 58+/-13 vs 67+/-11 years, p<0.001). The prevalence of arterial hypertension was higher in patients with distal dissection compared with those with proximal. Aortic atherosclerosis was present in less patients with proximal than with distal dissection (67% vs 94%, p<0.002). Logistic regression analysis revealed that patients with severe atherosclerosis were 7.6-fold more probable to have type B than type A dissection (p<0.001). CONCLUSION: Aortic atherosclerosis is more associated with distal than with proximal aortic dissection.     

Splenic and mesenteric emboli in a patient with protruding aortic arch atheroma

Protruding atheromas in the thoracic aorta are an important cause of embolic disease. Transesophageal echocardiography (TEE) is the modality of choice for diagnosis of these lesions. We present a patient with splenic infarction in whom TEE revealed a large mobile atheroma in the aortic arch. A few hours following the disappearance of this mass from the aortic arch, the patient developed mesenteric artery embolism requiring subtotal small-bowel resection. We discuss the importance of the aortic arch as a source of peripheral emboli and the treatment modalities in these patients.     

Routine transesophageal echocardiography for the evaluation of cerebral emboli in elderly patients

BACKGROUND: Approximately 20% of cerebral infarctions are cardioembolic in nature. Transesophageal echocardiography (TEE) is widely regarded as the initial study of choice for evaluating cardiac source of embolism. Although the majority of cerebrovascular accidents occur in elderly patients, the value of TEE in this population is poorly defined. METHODS: We compared 491 patients older than 65 years with suspected embolic stroke or transient ischemic attack (TIA) who had undergone TEE evaluation between April 2000 and February 2004 to an age-, sex-, and time-matched control group that consisted of 252 patients. Studies were reviewed for abnormalities associated with thromboembolic disease. RESULTS: The overall incidence of stroke risk factors was significantly higher in the study than in the control group. However, the four patients with left atrial thrombi had a history of atrial fibrillation. Although ascending and aortic arch sessile atheromata were observed more frequently in the study than control group, there were no significant differences in the incidence of either complex or mobile aortic atheromata. The incidence of atrial septal aneurysm was higher in the stroke/TIA group, but not in association with patent foramen ovale. Finally, there were also no differences in the incidence of spontaneous echocontrast, and/or patent foramen ovale between study and control groups. CONCLUSIONS: We conclude: (1) There is a higher incidence of abnormalities implicated as sources of thromboembolic disease on TEE in elderly patients with cerebral infarctions, but (2) this incidence is driven by the presence of sessile aortic atheroma and atrial septal aneurysm. Until the benefits of specific therapies for these conditions are known, routine TEE in elderly patients with suspected embolic neurological events appears to be unwarranted.     

Transesophageal Echocardiographic Correlates of Clinical Risk of Thromboembolism in Nonvalvular Atrial Fibrillation

Objectives. This study explored the mechanisms linking clinical and precordial echocardiographic predictors to thromboembolism in atrial fibrillation (AF) by assessing transesophageal echocardiographic (TEE) correlations.

Background. Clinical predictors of thromboembolism in patients with nonvalvular AF have been identified, but their mechanistic links remain unclear. TEE provides imaging of the left atrium, its appendage and the proximal thoracic aorta, potentially clarifying stroke mechanisms in patients with AF.

Methods. Cross-sectional analysis of TEE features correlated with low, moderate and high thromboembolic risk during aspirin therapy among 786 participants undergoing TEE on entry into the Stroke Prevention in Atrial Fibrillation III trial.

Results. TEE features independently associated with increased thromboembolic risk were appendage thrombi (relative risk [RR] 2.5, p = 0.04), dense spontaneous echo contrast (RR 3.7, p < 0.001), left atrial appendage peak flow velocities ≤20 cm/s (RR 1.7, p = 0.008) and complex aortic plaque (RR 2.1, p < 0.001). Patients with AF with a history of hypertension (conferring moderate risk) more frequently had atrial appendage thrombi (RR 2.6, p < 0.001) and reduced flow velocity (RR 1.8, p = 0.003) than low risk patients. Among low risk patients, those with intermittent AF had similar TEE features to those with constant AF.

Conclusions. TEE findings indicative of atrial stasis or thrombosis and of aortic atheroma were independently associated with high thromboembolic risk in patients with AF. The increased stroke risk associated with a history of hypertension in AF appears to be mediated primarily through left atrial stasis and thrombi. The presence of complex aortic plaque distinguished patients with AF at high risk from those at moderate risk of thromboembolism.     

Embolic risk based on aortic atherosclerotic morphologic features and aortic spontaneous echocardiographic contrast.

BACKGROUND: Different aortic atherosclerotic plaque morphologic features may have varying embolic potentials. Spontaneous echocardiographic contrast (SEC) in the aorta, as in the left atrium, has been associated with an increased risk of embolic events and often occurs with complex aortic atherosclerosis. Thus an evaluation of their isolated and combined association with embolic events was undertaken. METHODS: We retrospectively studied all patients who underwent biplane or multiplane transesophageal echocardiography meeting the following inclusion and exclusion criteria: age >/=55 years and no other cardiac pathologic condition known to be associated with embolic events other than aortic atherosclerosis or aortic SEC. The 105 patients meeting the criteria were divided into those with aortic atherosclerosis and/or aortic SEC (the study group) and those without these aortic pathologic conditions (the comparison group). Complex aortic atherosclerosis was defined as mobile, ulcerated, or protuberant (> 4 mm). SEC was defined as a pulsatile, swirling echo pattern within the aortic lumen. Embolic events included strokes, transient ischemic attacks, or peripheral emboli. RESULTS: The 61 study patients and 44 comparison patients did not significantly differ with respect to the reason for referral, age, or sex. Embolic events occurred in 35 patients. Those with ulcerated or mobile plaques had a greater prevalence of embolic events (odds ratio 4.50; 95% confidence interval, 1.30-15.5; P <.05). The highest embolic event rate was seen in patients with any complex atherosclerosis and concomitant SEC (odds ratio 9.00; 95% confidence interval, 2.06-39.3; P <.01). Patients with SEC alone or protuberant plaques alone did not have a higher event rate (odds ratio 1.71 and 0.60; 95% confidence interval, 0.57-5.17 and 0.15-2. 47, respectively). CONCLUSIONS: Embolic events were associated with the presence of ulcerated or mobile aortic plaques. In addition, the combination of aortic SEC and any complex atherosclerosis had the highest embolic association.     

Cerebral diffusion-weighted magnetic resonance imaging: a tool to monitor the thrombogenicity of left atrial catheter ablation

INTRODUCTION: Cerebral embolism and stroke are feared complications of left atrial catheter ablation such as pulmonary vein (PV) ablation. In order to assess the thrombogenicity of left atrial catheter ablation, knowledge of both clinically evident as well as silent cerebral embolism is important. The aim of the current study was to examine the use of diffusion-weighted magnetic resonance imaging (DW-MRI) for detection of cerebral embolism, apparent as well as silent, caused by PV catheter ablation. METHODS AND RESULTS: Twenty consecutive patients without structural heart disease undergoing lasso catheter-guided ostial PV ablation using an irrigated-tip ablation catheter were studied. Cerebral MRI including DW single-shot spin echo echoplanar, turbo fluid attenuated inversion recovery, and T2-weighted turbo spin echo sequences were performed the day after the ablation procedure. Ten patients also underwent preprocedure cerebral MRI. All ablation procedures were performed without acute complications. A mean of 3.2 +/- 0.6 PVs were ablated per patient. No patient had neurological symptoms following the procedure. In 2 of 20 patients (10%), DW-MRI revealed new embolic lesions, which were located in the right periventricular white matter in one and in the left temporal lobe in the other patient. There was no statistically significant difference in age, history of hypertension, left atrial volume, and procedure duration between the 2 patients with and the 18 patients without cerebral embolism following AF ablation. CONCLUSION: This is the first study using highly sensitive DW-MRI of the brain to detect asymptomatic cerebral embolism after left atrial catheter ablation. Even small, clinically silent, embolic lesions can be demonstrated with this technique. DW-MRI can be used to monitor and compare the thrombogenicity of different AF ablation approaches.     

Retrograde embolism from the descending thoracic aorta causing stroke: An underappreciated clinical condition

The mechanism of retrograde aortic blood flow is a complex and underreported clinical phenomenon. Complex plaques of the aortic arch are considered high-risk sources of cerebral emboli.¹ Aortic plaques situated in the descending thoracic aorta are however often overlooked and in fact can be more frequent potential sources of cerebral embolism through the mechanism of retrograde aortic blood flow. We present the case of an elderly Caucasian female who experienced recurrent posterior circulation embolic strokes where the only possible underlying etiology was found to be an atheroma in the descending thoracic aorta, possibly showering retrograde emboli.     

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.     

Retrograde flow in the thoracic aorta in patients with systemic emboli: a transesophageal echocardiographic evaluation of mobile plaque motion

STUDY OBJECTIVES: Blood flow in the aorta is complex and incompletely characterized. Mobile aortic plaques (MAPs), moving freely with the pulsatile aortic flow, in fact represent natural tracers that reflect the flow pattern itself. Our aim was to use MAP motion on transesophageal echocardiography (TEE) in order to characterize flow patterns in the atheromatous thoracic aorta of patients with systemic emboli. DESIGN AND PATIENTS: The study group was recruited from 250 patients referred for TEE to evaluate recent embolism. Among them, 22 patients (14 men and 8 women; mean +/- SD age, 66.3 +/- 7.2 years; 16 patients with cerebrovascular and 6 patients with peripheral emboli) with MAPs of > or = 3 mm in length formed the study group. The longest amplitudes of three spatial components of mobile lesion motions were measured: x (antegrade/retrograde [A/R]), y (up/down [U/D], and z (right/left [R/L]). RESULTS: A total of 33 mobile lesions were detected: 3 in the ascending aorta (1 patient), 13 in the arch (10 patients), and 17 in the descending aorta (11 patients). The length of mobile plaque components ranged from 3 to 13 mm; amplitudes of A/R, U/d, R/L, and retrograde flow motions ranged from 3 to 26 mm, from 1 to 16 mm, from 1 to 17 mm, and from 1 to 13 mm, respectively. Systolic rotational motion was clockwise in six patients (27%), counterclockwise in five patients (23%), incomplete (semicircle) in six patients (27%), and alternate clockwise/counterclockwise in five patients (23%). Diastolic rotational motion was clockwise in 5 patients (23%), counterclockwise in 6 patients (27%), and incomplete (semicircle) in 11 patients (50%). There were 18 multiple MAPs in seven patients: in all these cases, simultaneous rotations of MAP in different directions (as a marker for the presence of multiple vortices) were found. In nine patients with cerebral embolism, MAPs on the distal part of aortic arch solely were found; in five of them, all alternative potential sources of stroke were excluded. Therefore, retrograde cerebral embolism from distal aortic plaques in these patients is highly probable. CONCLUSIONS: Retrograde and rotational blood flow in the thoracic aorta probably exists in all patients with systemic emboli and mobile protruding aortic atheromas. Therefore, retrograde cerebral embolism from distal aortic plaques is theoretically possible.     

Utility of transesophageal echocardiography in identification of thrombogenic milieu in patients with atrial fibrillation (an ACUTE ancillary study)

The ACUTE trial randomly assigned patients who had atrial fibrillation (AF) of >2 days' duration to a transesophageal echocardiographically guided or a conventional strategy before cardioversion. In the 571 patients who underwent transesophageal echocardiography (TEE) in the ACUTE trial, we assessed the relative predictive value of baseline data derived by history, transthoracic echocardiography, and TEE for prediction of thrombus and adjudicated embolism (thromboembolism) as a composite end point. TEE was performed at 70 centers in 571 patients, 549 in the transesophageal echocardiographically guided group and 22 crossovers in the conventional group. Six patients (1.1%) who had embolism and 79 (13.8%) who had thrombi were identified in this group. Thrombus was completely resolved in 76.5% of patients who had repeat transesophageal echocardiographic procedures after 31.7 +/- 7.5 days of anticoagulation. For patients who had embolic events, none had a transesophageal echocardiographically identified thrombus; 5 of 6 (83.3%) had >/=1 transesophageal echocardiographic risk factors (including spontaneous echocardiographic contrast, aortic atheroma, patent foramen ovale, atrial septal aneurysm, mitral valve strands), and 4 of 6 (66.66%) had subtherapeutic anticoagulation or no anticoagulation. Clinical, transthoracic echocardiographic, and transesophageal echocardiographic risk factors contributed significantly to the prediction of composite thrombus/embolism. However, transesophageal echocardiographic thromboembolic risk factors were the strongest predictors of thromboembolism and provided statistically significant incremental value (chi-square 38.0, p <0.001) for identification of risk. Thus, in addition to thrombus identification, TEE has significant incremental value in the identification of patients who had high thromboembolic risk. In conclusion, this study supports the role of TEE and anticoagulation monitoring in patients who have atrial fibrillation and is useful for identifying thromboembolic risk factors.     

Age-Dependent Prevalence of Cardioembolic Sources Detected by TEE: Diagnostic and Therapeutic Implications

To define the prevalence of cardioembolic sources found by transesophageal echocardiography (TEE) in different age groups of patients with and without cryptogenic systemic embolism, TEE risk factors for cardiogenic embolism were identified from 341 consecutive patients referred for TEE. One hundred and thirty-five had cryptogenic cerebral or systemic peripheral embolic events (CEE) and 206 other indications for TEE (CTR). Cardioembolic sources were found in 40% of CEE and in 29% of CTR (P < 0.02). Specifically, left atrial (LA) thrombi (P < 0.0001), atrial septal aneurysm with right-to-left shunt (P < 0.002), and atherosclerotic aortic plaques (P < 0.02) were more frequent. The prevalence of potential cardioembolic sources was significantly higher in patients ≥ 70-years old than in younger patients (P < 0.03), specifically LA thrombi (P < 0.004) and atherosclerotic aortic plaques (P < 0.0001). In patients ≥ 70-years old, potential cardioembolic sources were found in 63% and in 40% in CEE and CTR (P = 0.073), respectively. However, LA thrombi were more frequent in CEE (P < 0.003). Thus, potential cardioembolic sources observed by TEE are found more frequently in patients ≥ 70-years old than in younger patients. LA thrombi were more frequent in CEE than in CTR patients ≥ 70-years old. In patients ≥ 70-years old with CEE who are eligible for an anticoagulant regimen, a search for potential cardioembolic sources by TEE should be considered.     

Association of transesophageal echocardiographic findings with the site of arterial occlusion in patients with thromboembolic stroke

The authors investigated the association of transesophageal echocardiographic findings with the site of arterial occlusion in patients who underwent transesophageal echocardiography because of thromboembolic stroke and in whom the site of arterial occlusion was diagnosed by computerized axial tomography. The study population included 101 patients (mean age 59 +/- 15 years) with thromboembolic stroke and 101 randomly selected age-matched and sex-matched control without stroke. Transesophageal echocardiographic findings that were significantly higher in the patients with thromboembolic stroke than in the control group were vegetations on the aortic or mitral valve (9% versus 1%, P < 0.01), left atrial or left atrial thrombus or spontaneous echocardiographic contrast (20% versus 6%, P < 0.005), thrombus on a prosthetic valve or in the left ventricle (4% versus 0%, P < 0.05), and atherosclerosis in the thoracic aorta (37% versus 21%, P < 0.02). A higher prevalence of atherosclerosis in the thoracic aorta was found in patients with lacunar infarction compared with patients with middle cerebral artery occlusion (67% versus 25%, P < 0.02), as well as a higher prevalence of vegetations on the aortic or mitral valve in patients with occlusion of 2 arteries compared with patients with vertebrobasilar artery occlusion (28% versus 0%, P < 0.05).