Transoesophageal echocardiography in selecting patients for anticoagulation after ischaemic stroke or transient ischaemic attack

Multimodal Cardiac Imaging in the Assessment of Patients Who Have Suffered a Cardioembolic Stroke: A Review

Cardioembolic strokes account for 20-25% of all ischaemic strokes, with their incidence increasing with age. Cardiac imaging plays a crucial role in identifying cardioembolic causes of stroke, with early and accurate identification affecting treatment, preventing recurrence, and reducing stroke incidence. Echocardiography serves as the mainstay of cardiac evaluation. Transthoracic echocardiography (TTE) is the first line in the basic evaluation of structural heart disorders, valvular disease, vegetations, and intraventricular thrombus. It can be used to measure chamber size and systolic/diastolic function. Trans-oesophageal echocardiography (TOE) yields better results in identifying potential cardioembolic sources of stroke and should be strongly considered, especially if TTE does not yield adequate results. Cardiac computed tomography and cardiac magnetic resonance imaging provide better soft tissue characterisation, high-grade anatomical information, spatial and temporal visualisation, and image reconstruction in multiple planes, especially with contrast. These techniques are useful in cases of inconclusive echocardiograms and can be used to detect and characterise valvular lesions, thrombi, fibrosis, cardiomyopathies, and aortic plaques. Nuclear imaging is not routinely used, but it can be used to assess left-ventricular perfusion, function, and dimensions and may be useful in cases of infective endocarditis. Its use should be considered on a case-by-case basis. The accuracy of each imaging modality depends on the likely source of cardioembolism, and the choice of imaging approach should be tailored to individual patients.

Evaluation of causal heart diseases in cardioembolic stroke by cardiac computed tomography

Cardioembolic stroke is a potentially devastating condition and tends to have a poor prognosis compared with other ischemic stroke subtypes. Therefore, it is important for proper therapeutic management to identify a cardiac source of embolism in stroke patients. Cardiac computed tomography (CCT) can detect the detailed visualization of various cardiac pathologies in the cardiac chambers, interatrial and interventricular septum, valves, and myocardium with few motion artifacts and few dead angles. Multiphase reconstruction images of the entire cardiac cycle make it possible to demonstrate cardiac structures in a dynamic manner. Consequently, CCT has the ability to provide high-quality information about causal heart disease in cardioembolic stroke. In addition, CCT can simultaneously evaluate obstructive coronary artery disease, which may be helpful in surgical planning in patients who need urgent surgery, such as cardiac tumors or infective endocarditis. This review will introduce the potential clinical applications of CCT in an ischemic stroke population, with a focus on diagnosing cardioembolic sources using CCT.

Clinical Utility of the Transthoracic Echocardiogram for Isolated Lacunar Infarcts: A Single-Center Experience

BACKGROUND

Stroke is a prominent and financially burdensome disease. Lacunar strokes are traditionally attributed to small vessel disease rather than cardioemboli, which typically occlude larger arteries. Thus, the benefit of screening for potential sources of cardioemboli in lacunar stroke patients is unclear. We evaluated the clinical utility of the transthoracic echocardiogram performed in patients with lacunar strokes.

METHODS

A single-center retrospective analysis of ischemic stroke patients from January 2013 through December 2017 was performed. Brain magnetic resonance imaging was used to select patients with a single lacunar infarct. Patients presenting with acute symptoms of cardiac disease or an abnormal electrocardiogram were excluded. Transthoracic echocardiogram results were reviewed, and their utility in decision-making was evaluated.

RESULTS

Of the 442 patients at our institution diagnosed with ischemic stroke during the inclusion period, 89 met inclusion criteria. Transthoracic echocardiogram detected a patent foramen ovale in 5.6% of patients, mitral annular calcification in 9.0% of patients, and abnormal wall motion in 4.5% of patients. For all patients, there were no findings that prompted anticoagulation, antibiotic, or surgical intervention. The cost of an inpatient transthoracic echocardiogram is $4100, resulting in $364,900 in unnecessary health care spending.

CONCLUSIONS

Transthoracic echocardiogram appears to have minimal therapeutic value in most patients with lacunar strokes. In stroke patients with no acute symptoms of cardiac disease and a normal electrocardiogram, it may be reasonable to forgo the transthoracic echocardiogram if the brain magnetic resonance imaging shows an isolated lacunar infarct.

Overview of Acute Ischemic Stroke Evaluation and Management

Stroke is a major contributor to death and disability worldwide. Prior to modern therapy, post-stroke mortality was approximately 10% in the acute period, with nearly one-half of the patients developing moderate-to-severe disability. The most fundamental aspect of acute stroke management is "time is brain". In acute ischemic stroke, the primary therapeutic goal of reperfusion therapy, including intravenous recombinant tissue plasminogen activator (IV TPA) and/or endovascular thrombectomy, is the rapid restoration of cerebral blood flow to the salvageable ischemic brain tissue at risk for cerebral infarction. Several landmark endovascular thrombectomy trials were found to be of benefit in select patients with acute stroke caused by occlusion of the proximal anterior circulation, which has led to a paradigm shift in the management of acute ischemic strokes. In this modern era of acute stroke care, more patients will survive with varying degrees of disability post-stroke. A comprehensive stroke rehabilitation program is critical to optimize post-stroke outcomes. Understanding the natural history of stroke recovery, and adapting a multidisciplinary approach, will lead to improved chances for successful rehabilitation. In this article, we provide an overview on the evaluation and the current advances in the management of acute ischemic stroke, starting in the prehospital setting and in the emergency department, followed by post-acute stroke hospital management and rehabilitation.

Treatment-Relevant Findings in Transesophageal Echocardiography After Stroke: A Prospective Multicenter Cohort Study

BACKGROUND AND PURPOSE

Cardiac ultrasound to identify sources of cardioembolism is part of the diagnostic workup of acute ischemic stroke. Recommendations on whether transesophageal echocardiography (TEE) should be performed in addition to transthoracic echocardiography (TTE) are controversial. We aimed to determine the incremental diagnostic yield of TEE in addition to TTE in patients with acute ischemic stroke with undetermined cause.

METHODS

In a prospective, observational, pragmatic multicenter cohort study, patients with acute ischemic stroke or transient ischemic attack with undetermined cause before cardiac ultrasound were studied by TTE and TEE. The primary outcome was the rate of treatment-relevant findings in TTE and TEE as defined by a panel of experts based on current evidence. Further outcomes included the rate of changes in the assessment of stroke cause after TEE.

RESULTS

Between July 1, 2017, and June 30, 2019, we enrolled 494 patients, of whom 492 (99.6%) received TTE and 454 (91.9%) received TEE. Mean age was 64.7 years, and 204 (41.3%) were women. TEE showed a higher rate of treatment-relevant findings than TTE (86 [18.9%] versus 64 [14.1%], P<0.001). TEE in addition to TTE resulted in 29 (6.4%) additional patients with treatment-relevant findings. Among 191 patients ≤60 years additional treatment-relevant findings by TEE were observed in 27 (14.1%) patients. Classification of stroke cause changed after TEE in 52 of 453 patients (11.5%), resulting in a significant difference in the distribution of stroke cause before and after TEE (P<0.001).

CONCLUSIONS

In patients with undetermined cause of stroke, TEE yielded a higher number of treatment-relevant findings than TTE. TEE appears especially useful in younger patients with stroke, with treatment-relevant findings in one out of seven patients ≤60 years.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03411642.

Expert opinion paper on cardiac imaging after ischemic stroke

This expert opinion paper on cardiac imaging after acute ischemic stroke or transient ischemic attack (TIA) includes a statement of the "Heart and Brain" consortium of the German Cardiac Society and the German Stroke Society. The Stroke Unit-Commission of the German Stroke Society and the German Atrial Fibrillation NETwork (AFNET) endorsed this paper. Cardiac imaging is a key component of etiological work-up after stroke. Enhanced echocardiographic tools, constantly improving cardiac computer tomography (CT) as well as cardiac magnetic resonance imaging (MRI) offer comprehensive non- or less-invasive cardiac evaluation at the expense of increased costs and/or radiation exposure. Certain imaging findings usually lead to a change in medical secondary stroke prevention or may influence medical treatment. However, there is no proof from a randomized controlled trial (RCT) that the choice of the imaging method influences the prognosis of stroke patients. Summarizing present knowledge, the German Heart and Brain consortium proposes an interdisciplinary, staged standard diagnostic scheme for the detection of risk factors of cardio-embolic stroke. This expert opinion paper aims to give practical advice to physicians who are involved in stroke care. In line with the nature of an expert opinion paper, labeling of classes of recommendations is not provided, since many statements are based on expert opinion, reported case series, and clinical experience.

Clinical utility of echocardiography in secondary ischemic stroke prevention

Echocardiography employs ultrasound to evaluate cardiac function, structure and pathology. The clinical value in secondary ischemic stroke prevention depends on identification of associated conditions for which a change in treatment from antiplatelet agents and risk factor intervention leads to improved outcomes. Such therapeutically relevant findings include primarily intracardiac thrombus, valvular heart disease and, in highly selected patients, patent foramen ovale (PFO). Echocardiography in unselected patients with ischemic stroke has a very low yield of therapeutically relevant findings and is not cost-effective. With the exception of PFO, findings on echocardiography that are therapeutically relevant for secondary stroke prevention are almost always associated with history, signs or symptoms of cardiac or systemic disease. Choice of specific echocardiographic modalities should be based on the specific pathology or pathologies that are under consideration for the individual clinical situation. Transthoracic echocardiography (TTE) with agitated saline has comparable accuracy to transesophageal echocardiography (TEE) for PFO detection. For other therapeutically relevant pathologies, with the possible exception of left ventricular thrombus (LVT), TEE is more sensitive than TTE. Professional societies recommend TTE as the initial test but these recommendations do not take cost into account. In contrast, cost-effectiveness studies have determined that the most sensitive echocardiographic modality should be selected as the initial and only test.

Association of ABCB1 C3435T Polymorphism with Echocardiographic Index Among Patients with Atherosclerotic Ischemic Stroke and Transient Ischemic Attack

Emerging evidence has suggested that patients with ischemic stroke (IS) and/or transient ischemic attack (TIA) are more likely to exhibit myocardial disorders, which can be reflected by transthoracic echocardiography (TTE). ATP binding cassette transporter 1 (ABCB1) plays an important role in the development and progression of atherosclerotic pathology. The objective of the current study was to investigate the associations of ABCB1 C3435T polymorphism with echocardiographic performances among patients with acute ischemic stroke. Patients with IS or TIA, who were hospitalized and received TTE between October 2016 to March 2019, were enrolled in this study. Demographic data and echocardiographic parameters of each participant were recorded. We included 122 patients, with the respective distribution of 12.30%, 48.36%, and 39.34% in CC, CT, and TT genotypes. There were significant differences among the three ABCB1 types, with respect to RV (P = 0.036). The presence of the TT genotype was associated with increased MVE (OR = 0.13, P = 0.02) but correlated with decreased RV (OR = -1.46, P = 0.02). Our study indicated that ABCB1 C3435T polymorphism is associated with echocardiographic parameters among patients with acute ischemic stroke. The presence of the TT genotype is associated with diastolic function and cardiac hypertrophy.

Cardiac imaging after ischemic stroke : Echocardiography, CT, or MRI?

About 20–25% of all ischemic strokes are of cardioembolic etiology, with atrial fibrillation and heart failure as the most common underlying pathologies. Diagnostic work-up by noninvasive cardiac imaging is essential since it may lead to changes in therapy, e.g., in—but not exclusively—secondary stroke prevention. Echocardiography remains the cornerstone of cardiac imaging after ischemic stroke, with the combination of transthoracic and transesophageal echocardiography as gold standard thanks to their high sensitivity for many common pathologies. Transesophageal echocardiography should be considered as the initial diagnostic tool when a cardioembolic source of stroke is suspected. However, to date, there is no proven benefit of transesophageal echocardiography-related therapy changes on the main outcomes after ischemic stroke. Based on the currently available data, cardiac computed tomography and magnetic resonance imaging should be regarded as complementary methods to echocardiography, providing additional information in specific situations; however, they cannot be recommended as first-line modalities.

The cardiac diagnostic work-up in stroke patients-A subanalysis of the Find-AFRANDOMISED trial

Background

The cardiac diagnostic workup of stroke patients, especially the value of echocardiography and enhanced and prolonged Holter-ECG monitoring, is still a matter of debate. We aimed to analyse the impact of pathologies detected by echocardiography and ECG monitoring on therapeutic decisions and prognosis.

Methods

Find-AF_RANDOMISED was a prospective multicenter study which randomised 398 acute ischemic stroke patients ≥ 60 years to enhanced and prolonged Holter-ECG monitoring or usual stroke unit care. This substudy compared therapeutic consequences of echocardiography and routine Holter-ECG or enhanced and prolonged Holter-ECG monitoring, respectively, and prognosis of patients with or without pathologic findings in echocardiography or Holter-ECG monitoring.

Results

50.3% received enhanced and prolonged Holter-ECG monitoring and 49.7% routine ECG monitoring. 82.9% underwent transthoracic echocardiography (TTE), 38.9% transesophageal echocardiography (TEE) and 25.6% both procedures. 14/89 TEE pathologies and 1/90 TTE pathology led to a change in therapy, resulting in a number needed to change decision (NNCD) of 12 and 330 (p < 0.001), respectively. In comparison, enhanced and prolonged Holter-ECG monitoring found atrial fibrillation (AF) in 27 of 200 patients, and routine ECG monitoring in twelve of 198 patients, leading to therapeutic changes in all patients (NNCD 8 and 17, respectively, p < 0.001).

Conclusions

Most changes in therapeutic decisions were triggered by enhanced and prolonged Holter-ECG monitoring, which should therefore play a more prominent role in future guidelines. Echocardiography identifies a patient group at high cardiovascular risk, but rarely result in therapeutic changes. Whether this patient group requires further cardiovascular workup remains unknown. This should be further investigated by interdisciplinary neurocardiologic teams and in appropriate future trials.

Trial registration

ClinicalTrials.gov NCT01855035

Is transesophageal echocardiography needed for evaluating tissue-based transient ischemic attack?

Transient ischemic attack (TIA) is a warning signal for stroke. A comprehensive evaluation of TIA may reduce the risk for subsequent stroke. Data on the findings of cardiac evaluation with transesophageal echocardiography (TEE) in patients with TIA are sparse. Our aims were to determine the frequency of TEE performance and to investigate the findings of TEE in patients with TIA based on the new definition of TIA (i.e., transient neurological symptoms without evidence of infarction). During a 4-year period (2011-2014), 1071 patients (mean age, 70 ± 13 years; female, 49.7%) with TIA were included in a prospective study and evaluated. Of 1071 consecutive patients suffering from TIA, 288 patients (27%) underwent TEE. The median time between admission and TEE was 6 days. Patients with TIA who were evaluated by TEE were younger (67 vs. 71 years, P < 0.001) than those who were not evaluated by TEE. They had a higher rate of sensibility disturbance as a TIA symptom (39% vs. 31%, P = 0.012) but a lower rate of previous stroke (15% vs. 25%, P = 0.001) and atrial fibrillation (2% vs. 21%, P < 0.001) than those who did not. Foramen ovale was detected in 71 patients (25.7%), atrial septal aneurysm in 13 patients (4.6%), and severe atherosclerotic plaques (grade 4 and 5) in the aortic arch in 25 patients (8.7%). One patient (0.3%) had a fibroma detected by TEE. In 17 of the 288 patients (6%) who underwent TEE, the indication for anticoagulation therapy was based on the TEE results, and 1 patient with fibroma underwent heart surgery. During hospitalization, 7 patients experienced a subsequent stroke, and 27 patients had a recurrent TIA. At 3 months following discharge, the rates of readmission, stroke, recurrent TIA, and death were 19%, 2.7%, 4.2%, and 1.6%, respectively. The rates of mortality (0.9% vs. 1.8%, P = 0.7), stroke risk (1.9% vs. 3.0%, P = 0.8), and recurrent TIA (5.0% vs. 3.9%, P = 0.8) were similar in patients who underwent TEE and in those who did not. Performing TEE in patients with tissue-based TIA is helpful in detecting cardiac sources for embolism and may indicate for anticoagulation.

Diagnostic Impact of Transesophageal Echocardiography in Patients with Acute Cerebral Ischemia

OBJECTIVES

Transesophageal echocardiography (TEE) is the diagnostic gold standard for the detection of structural heart diseases as potential sources of cardiac emboli in patients with acute cerebral ischemia. We sought to determine the diagnostic yield of TEE in patients with acute ischemic stroke or transient ischemic attack (TIA).

METHODS

We retrospectively analyzed consecutive patients with acute cerebral ischemia who were admitted to our hospital between October 2008 and December 2011. TEE reports were screened for detection of cardiac source of embolism judged by the recommendation to change medical management. We performed univariate and multivariate analyses to identify predictors of clinically relevant TEE findings among baseline characteristics.

RESULTS

Of 3314 patients with ischemic stroke or TIA, TEE was performed in 791 (24%) patients (mean age 64 ± 13 years, 589 [74%] ischemic stroke, 202 [26%] TIA). A potential cardioembolic source was found in 71 (9%) patients with patent foramen ovale with atrial septal aneurysm being the most common finding (24/71 patients, 34%). In multivariate analysis, peripheral vascular disease (OR 2.57; 95%CI 1.00-6.61), imaging evidence of infarction in multiple locations (OR 4.13; 95%CI 1.36-12.58), and infarction in the posterior circulation (OR 2.11; 95%CI 1.01-4.42) were associated with the identification of a potential cardioembolic source with TEE.

CONCLUSION

TEE identified a potential structural cardioembolic source in nearly 10% of our selected patient population with acute ischemic stroke or TIA, thus underlining its diagnostic value. Our data suggest that patients with hitherto unknown stroke etiology should be considered for additional TEE.

Guidelines for the Use of Echocardiography in the Evaluation of a Cardiac Source of Embolism

Embolism from the heart or the thoracic aorta often leads to clinically significant morbidity and mortality due to transient ischemic attack, stroke or occlusion of peripheral arteries. Transthoracic and transesophageal echocardiography are the key diagnostic modalities for evaluation, diagnosis, and management of stroke, systemic and pulmonary embolism. This document provides comprehensive American Society of Echocardiography guidelines on the use of echocardiography for evaluation of cardiac sources of embolism. It describes general mechanisms of stroke and systemic embolism; the specific role of cardiac and aortic sources in stroke, and systemic and pulmonary embolism; the role of echocardiography in evaluation, diagnosis, and management of cardiac and aortic sources of emboli including the incremental value of contrast and 3D echocardiography; and a brief description of alternative imaging techniques and their role in the evaluation of cardiac sources of emboli. Specific guidelines are provided for each category of embolic sources including the left atrium and left atrial appendage, left ventricle, heart valves, cardiac tumors, and thoracic aorta. In addition, there are recommendation regarding pulmonary embolism, and embolism related to cardiovascular surgery and percutaneous procedures. The guidelines also include a dedicated section on cardiac sources of embolism in pediatric populations.

Transoesophageal Echocardiography in Patients with Stroke and Low Risk of Embolic Etiology

Transoesophageal echocardiography (TEE) is currently the gold standard in the diagnosis of cardiac sources of embolization and the frequently discussed question is whether all patients with suspected embolic stroke should be screened by TEE. Based on the results of transthoracic echocardiography (TTE), we determined the significance of TEE in patients with ischemic stroke with low risk of embolic etiology. We made a retrospective evaluation of TEE examination in the period from 1st January 2000 to 31st December 2003 in patients with ischemic stroke and sinus rhythm and normal left ventricular function. TEE examination was done in 159 patients. A quarter of the patients had pathological findings in the heart: left atrial thrombus in nine (5.7%), spontaneous echocontrast in left atrium in 14 (8.8%), patent foramen ovale in 16 (10%) and other findings in seven (4.4%) patients. The finding of the thrombus or echocontrast in the left atrium correlated with the size of the left atrium and it was proved in the patients with left atrium of size above 39 mm. On the contrary, patent foramen ovale was found in younger patients (70 vs. 59 years). Our results have shown that TEE is of low relevance to patients with a normal transthoracic echocardiogram.

Predictors of Recurrent Stroke in Patients with Ischemic Stroke: Comparison Study between Transesophageal Echocardiography and Cardiac CT

PURPOSE

To investigate cardiac computed tomographic (CT) findings predictive of recurrent stroke in patients with ischemic stroke and determine the incremental risk stratification benefit of cardiac CT findings compared with transesophageal echocardiography (TEE) findings in patients with ischemic stroke.

MATERIALS AND METHODS

This single-center prospective study protocol was approved by the institutional review boards, and written informed consent was obtained from all patients. Among 548 consecutive patients, 374 patients with ischemic stroke (254 men and 120 women, with a mean age of 63.1 years) who underwent TEE and cardiac CT were prospectively enrolled in this study. TEE and cardiac CT images were assessed for cardioembolic sources, including thrombus, tumor, spontaneous echo contrast, valvular vegetation, atrial septal aneurysm, patent foramen ovale, and aortic plaque. The primary end point was stroke recurrence. Prognostic factors were assessed with Cox univariate and multivariate analysis. The integrated area under the receiver operating characteristic curve was calculated to compare the prognostic abilities of CT and TEE parameters.

RESULTS

During a median follow-up period of 433 days, there were a total of 28 recurrent stroke events. The TEE parameter of plaque complexity (hazard ratio, 13.512; 95% confidence interval: 3.668, 49.778; P < .001) and CT parameter of plaque complexity (hazard ratio, 32.538; 95% confidence interval: 7.544, 140.347; P < .001) were predictors of recurrent stroke. The time-dependent receiver operating characteristic curve analysis demonstrated no significant differences in prediction of recurrent stroke between TEE and CT parameters (integrated area under the receiver operating characteristic curve, 0.812 vs 0.840, respectively).

CONCLUSION

Complex aortic plaque evaluated with cardiac CT and TEE was associated with an increased risk of stroke recurrence in patients with ischemic stroke.

Impact of transesophageal echocardiography on management in patients with suspected cardioembolic stroke

Transesophageal echocardiography (TEE) is frequently performed in patients with acute ischemic cerebrovascular events to exclude a cardioembolic source. We aimed to determine the clinical impact of TEE on management. This is a retrospective single-center study of 1,458 consecutive patients hospitalized with acute ischemic stroke or transient ischemic attack who underwent TEE for evaluation of a suspected cardioembolic cause. Significant TEE findings were determined for each patient as recorded on the TEE report. The medical record was reviewed for baseline, clinical, and demographic variables and to determine whether significant management changes occurred as a result of the TEE findings. Potential significant changes in management included initiation of anticoagulation, placement of a patent foramen ovale (PFO) closure device, initiation of antibiotic therapy for endocarditis, surgical PFO closure, other cardiac surgery, and coil embolization of a pulmonary arteriovenous malformation. A significant change in management occurred in 243 patients (16.7%); 173 (71%) underwent treatment for PFO with a percutaneous PFO closure device (n = 100), initiation of chronic systemic anticoagulation (n = 68), or surgical PFO closure (n = 5). Additional findings leading to a change in management included endocarditis (n = 20), aortic arch atheroma (n = 14), intracardiac thrombus (n = 13), pulmonary arteriovenous malformation (n = 2), aortic valve fibroelastoma (n = 2), other valve masses (n = 4), and miscellaneous causes (n = 15). In conclusion, in patients with suspected cardioembolic stroke, TEE findings led to a change in management in 16.7% of patients. Of these, most (71%) were directed at prevention of subsequent paradoxical emboli in patients with PFO.

Cardioembolic stroke is frequent in late recurrence after transient ischemic attack

BACKGROUND

Transient ischemic attack (TIA) is often followed by a stroke episode. Differences between early and late recurrent stroke, however, have not been elucidated.

METHODS

We enrolled 133 consecutive patients with acute ischemic stroke who presented to our hospital and had previously been diagnosed with TIA. They were divided into 5 groups according to the interval between TIA and subsequent stroke: <48 hours (group 1); 48 hours to 1 week (group 2); 1 week to 1 month (group 3); 1 month to 3 months (group 4); and >3 months (group 5). Patients who underwent recurrent stroke within and after 1 week subsequent to TIA (the early and late recurrence groups, respectively) were compared with regard to clinical findings.

RESULTS

Of the 133 patients, 46 (34.6%) were in group 1, 29 (21.8%) in group 2, 23 (17.3%) in group 3, 18 (13.5%) in group 4, and 17 (12.8%) in group 5. Most of the noncardioembolic strokes were observed shortly after TIA, while the percentage of cardioembolic stroke remained high even after long post-TIA periods. The prevalence of atrial fibrillation (AF) was higher in the late recurrence group than in the early recurrence group (41.4% v 24.0%, P = .033). Among 42 patients with AF, 12 (28.6%) were newly diagnosed at the time of stroke.

CONCLUSIONS

The frequency of cardioembolic stroke did not decline as time after TIA passed. More than one quarter of AF patients had been asymptomatic before stroke, suggesting the need for repeated examinations to detect AF in patients with TIA of unknown etiology.

Cardiac workup of ischemic stroke

Stroke is the leading cause of disability in developed countries and the third cause of mortality. Up to 15-30% of ischemic strokes are caused by cardiac sources of emboli being associated with poor prognosis and high index of fatal recurrence. In order to establish an adequate preventive strategy it is crucial to identify the cause of the embolism. After a complete diagnostic workup up to 30% of strokes remain with an undetermined cause, and most of them are attributed to an embolic mechanism suggesting a cardiac origin.There is no consensus in the extent and optimal approach of cardiac workup of ischemic stroke. Clinical features along with brain imaging and the study of the cerebral vessels with ultrasonography or MRI/CT based angiography can identify other causes or lead to think about a possible cardioembolic origin.Atrial fibrillation is the most common cause of cardioembolic stroke. Identification of occult atrial fibrillation is essential. Baseline ECG, serial ECG('s), cardiac monitoring during the first 48 hours, and Holter monitoring have detection rates varying from 4 to 8% each separately. Extended cardiac monitoring with event loop recorders has shown higher rates of detection of paroxysmal atrial fibrillation.Cardiac imaging with echocardiography is necessary to identify structural sources of emboli. There is insufficient data to determine which is the optimal approach. Transthoracic echocardiography has an acceptable diagnostic yield in patients with heart disease but transesophageal echocardiography has a higher diagnostic yield and is necessary if no cardiac sources have been identified in patients with cryptogenic stroke with embolic mechanism.

Transesophageal echocardiography screening in subjects with a first cerebrovascular ischemic event

Our goal was to develop decision guides to predict the presence of a high-risk source of embolus and to predict a change in management following transesophageal echocardiography (TEE) in subjects who present with a first cerebral ischemic event. We conducted a retrospective review of subjects age ≥18 years who underwent TEE after a first ischemic event and were admitted to our stroke service between 2004 and 2007 (n = 287). A high-risk source of embolus and a change in clinical management (including medication changes or subsequent testing) were analyzed as separate endpoints, using multivariate techniques and receiver operating characteristic curves. We found that 14.3% of the subjects had a high-risk source, and an additional 61.3% had a potential (or low-risk) source of embolus. Increasing age and no history of diabetes mellitus were independently associated with a high-risk source of embolus. TEE would be recommended for nondiabetic individuals age ≥66 years (sensitivity, 68%; specificity, 76%). The area under the curve (AUC) for detecting a high-risk source was 0.773. TEE results changed medications or clinical management in 30.3% of the subjects. Current smokers were less likely to undergo a change in management. The AUC was uninformative (0.56) for predicting changes in management. Subjects presenting with a first ischemic event age ≥66 years may benefit from TEE. Although changes in management occurred in at least 30% of our cohort, no factors that predicted a change in management better than chance alone could be identified.

Stroke in younger patients: the heart of the matter

Stroke in young adults is not a rare entity, and often provides difficult management decisions for neurologists. The knowledge gained from stroke in older adults does not transfer easily to this younger group given the different causes of stroke observed. Cardiac causes of stroke are common in this group, but often consist of low risk cardiac lesions such as a patent foramen ovale. Appropriate investigation should follow a stepwise approach to initially exclude higher risk pathology for recurrent stroke such as arterial dissection. Similarly, stepwise application of cardiac investigations will allow early identification of significant pathology, with investigation for abnormalities of the inter-atrial septum reserved for those with no other identified cause of stroke. Bubble contrast echo is now widely available, and with improved image quality may be performed with either transthoracic or transoesophageal echo, as well as with transcranial Doppler. Following this approach, patients can be best categorised by the expected rate of recurrent stroke, as informed by observational studies. Appropriate secondary prevention can then be tailored to the recurrence rate, with anticoagulation and possibly device closure reserved for those at highest risk of recurrence.

Cardiac workup of ischemic stroke: can we improve our diagnostic yield?

BACKGROUND AND PURPOSE

Discovering potential cardiac sources of stroke is an important part of the urgent evaluation of the ischemic stroke patient as it often impacts treatment decisions that are essential for determining secondary stroke prevention strategies, yet the optimal approach to the cardiac workup of an ischemic stroke patient is not known.

METHODS

A review of the literature concerning the utility of cardiac rhythm monitoring (ECG, telemetry, Holter monitors, and event recorders) and structural imaging (transthoracic and transesophageal echocardiography) was performed.

RESULTS

Data supporting a definitive, optimal, and cost-effective approach are lacking, though some data suggest that appropriate patient selection can improve the diagnostic and therapeutic yield of rhythm monitoring and echocardiography in the evaluation of stroke etiology.

CONCLUSIONS

Based on available data, an algorithmic approach for the evaluation of patients with acute ischemic cerebrovascular events that takes into account therapeutic and diagnostic yield as well as cost-efficiency is proposed.

Diagnosis of ischemic stroke

Early stroke management, and early initiation of secondary stroke prevention, may improve outcomes in patients with acute ischemic stroke. However, <10% of patients with acute ischemic stroke arrive at the receiving hospital within 3 hours of symptom onset. Factors such as poor public awareness of symptoms, lack of rapid detection by emergency medical services (EMS), poor coordination between EMS and the hospital emergency department, or delay of diagnosis on arrival at the emergency department are all contributing factors in the failure to provide prompt diagnosis and treatment of acute ischemic stroke. This article focuses on the critical steps in diagnosing ischemic stroke, starting at the initial patient evaluation by emergency personnel. Stroke mimics and different imaging techniques that may be used in the differential diagnosis and evaluation of acute ischemic stroke are also discussed.

Intracardiac thrombi in pediatric patients: presentation profiles and clinical outcomes

We document the presentation profiles, treatment strategies, and clinical outcomes in a relatively large cohort of pediatric patients with intracardiac thrombi (ICT). We performed a retrospective review of patients diagnosed with ICT by echocardiography at a tertiary pediatric hospital during a 10-year period. These patients received medical therapy or thrombectomy. We provided echocardiographic descriptions of the ICT-size, chamber location, and mobility/morphology. The outcome measures were ICT (persistence, resolution, or embolization), effectiveness of therapy, and patient morbidity and mortality. There were 40 ICT diagnosed in 31 patients (22 males and 9 females). Mean age at diagnosis was 8.8 years (range, 15 days to 18 years). Overall mortality was 12/31 patients (39%); only one death was attributed to ICT embolization. Embolic events occurred in 4/31 patients (13%). The most common initial therapies included heparin infusion (n = 15), warfarin (n = 7), and aspirin (n = 7). The ICT resolved with medical therapy alone in 19/30 patients (63%). One patient required surgical thrombectomy. The cohort was divided into group 1 (dilated cardiomyopathy), group 2 (status post Fontan operation), and group 3 (other diagnoses). In group 1 (n = 11), there were 8 deaths. Embolization occurred in 2/5 large ICT, resulting in cerebral infarction and death (n = 1) and renal infarction (n = 1). The most common ICT location was the left ventricle (n = 10). Severe ventricular systolic dysfunction was present in 10/11 patients (91%). In group 2 (n = 9), there was 1 death. Embolization occurred in 1/7 large ICT, resulting in seizures and temporary paresis. All ICT were located in the Fontan pathway. Severe ventricular systolic dysfunction was present in 2/9 patients (22%). In group 3 (n = 11), there were 3 deaths. Embolization occurred in 1/9 small ICT, resulting in coronary emboli. ICT are most commonly diagnosed in pediatric patients with dilated cardiomyopathy or patients status post Fontan operation. The majority of ICT resolve with medical therapy. Larger ICT tend to embolize more frequently, and the morbidity secondary to embolization is significant. Rarely is mortality due to ICT embolization. The prognosis is poor for patients with left ventricular ICT or ICT in the presence of ventricular systolic dysfunction.

Carotid sonography and transesophageal echocardiography in patients with ischemic stroke or transient ischemic attack in the territory of the carotid artery

PURPOSE

To assess the benefit of combining carotid sonography and transesophageal echocardiography (TEE) for the evaluation of patients with stroke or transient ischemic attack (TIA) in the territory of the carotid artery.

METHODS

During a 2-year period in Turku University Hospital, consecutive in patients with stroke or TIA who were candidates for carotid endarterectomy and for oral anticoagulation were evaluated with carotid sonography for symptomatic moderate (50-69%) or severe (>or=70%) internal carotid artery (ICA) stenosis, and with TEE for potential cardiac sources of embolism.

RESULTS

In 20% (40/197) of patients, a severe symptomatic ICA stenosis and/or a major risk factor for a cardiac source of embolism were found. In 56% (110/197) of patients, a moderate or severe symptomatic ICA stenosis and/or a potential cardiac source of embolism were found, whereas 11% (21/197) of patients had both a moderate or severe symptomatic ICA stenosis and a potential cardiac source of embolism.

CONCLUSIONS

This study suggests that the presence of a moderate or severe symptomatic ICA stenosis does not exclude the presence of a potential cardiac source of embolism and vice versa. Carotid sonography and TEE complement each other and are valuable diagnostic tools that should be recommended in patients with ischemic stroke or TIA in the territory of the carotid artery when they are candidates for carotid endarterectomy and for oral anticoagulation.

Transesophageal Echocardiography Is Superior to Transthoracic Echocardiography in Management of Patients of Any Age With Transient Ischemic Attack or Stroke

Background and Purpose— The merits of transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) in the management of transient ischemic attack (TIA) and stroke patients remains matter of debate.

Methods— Two hundred and thirty-one consecutive patients with a recent TIA or stroke for which no definite cause and indication for anticoagulation was assessed after standardized work-up underwent TTE and TEE. Echocardiographic findings were categorized into minor and major risk factors.

Results— A potential cardiac source of embolism was detected in 55% (127/ 231) of the patients by echocardiography, in 39% (90/231) only identified on TEE. Major risk factors, with an absolute indication for oral anticoagulation, were detected in 20% (46/231) of the patients, in 16% (38/231) of all patients identified on TEE only. A thrombus in the left atrial appendage was the most common major risk factor (38 patients, 16%). The presence of major risk factors was independent of age (χ 2 =1.48; P =0.224). The difference in proportions of cardiac sources detected in favor of TEE was highly significant in both patients ≤45 years of age (10/39, P =0.002) and in those >45 years of age (80/192; P <0.004).

Conclusions— TEE proved superior to TTE for identification of a cardiac embolic source in patients with TIA or stroke without pre-existent indication or contraindication for anticoagulation. In patients with normal TTE, a cardiac source of embolism was detected by TEE in ≈40% of patients, independent of age. More than 1 of 8 patients of any age with normal TTE revealed a major cardiac risk factor on TEE, in whom anticoagulation is warranted.

Transesophageal Echocardiography Impacts Management and Evaluation of Patients with Stroke, Transient Ischemic Attack, or Peripheral Embolism

The relative impact of transesophageal echocardiography (TEE) on the management of patients with specific embolic events, namely nonhemorrhagic cerebrovascular accident (CVA), transient ischemic attack (TIA), or peripheral embolism is controversial. The impact of TEE in 234 adult subjects with CVA (n = 141), TIA (n = 59), or peripheral embolism (n = 34) was determined. TEE was diagnostic of a potential embolic source in 61%, 51%, and 62% of patients with CVA, TIA, and peripheral embolism, respectively (P = NS). TEE results changed medication or surgical treatment in 32%, 22%, and 32% of patients with CVA, TIA, and peripheral embolism, respectively (P = NS). Anticoagulation was started on the basis of TEE findings in 11%, 12%, and 18% of patients with CVA, TIA, and peripheral embolism, respectively (P = NS). In 77% of all patients, TEE findings confirmed as appropriate the empiric decision made prior to TEE, to anticoagulate (60%; 12/20) or not to anticoagulate (79%; 168/214). These data demonstrate that TEE findings have a significant and similar impact on the clinical management of patients with various types of potential embolism. Future studies addressing the effectiveness of treatment, guided by TEE findings, in the prevention of recurrent embolic events are needed.

Therapeutic Strategies After Examination by Transesophageal Echocardiography in 503 Patients With Ischemic Stroke

BACKGROUND AND PURPOSE

Transesophageal echocardiography (TEE) is the gold standard in detecting high-risk (ie, aortic thrombi) and potential sources (ie, patent foramen ovale [PFO]) of cerebral embolism. We sought to evaluate the additional information and therapeutic impact provided by TEE in stroke patients and to characterize patients in whom TEE is indispensable.

METHODS

We included 503 consecutive patients (mean age 62.2 years) with acute brain ischemia. Each patient received TEE and the following routine diagnostics: ultrasound of brain supplying arteries, ECG or Holter-ECG, transthoracic echocardiography, and brain imaging (computed tomography or MRI). Stroke etiology was classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. High-risk sources in TEE were: aortic thrombi or plaques > or =4 mm, thrombi in left atrial cavity/left atrial appendage, spontaneous echo contrast, and left atrial flow velocity <30 cm/s. Potential sources in TEE were PFO, atrial septal aneurysm, and aortic plaques <4 mm.

RESULTS

Stroke etiology was determined by routine diagnostics in 276 of 503 patients (54.9%). Of the remaining 227 patients (undetermined etiology), 212 (93.4%) were candidates for oral anticoagulation (OA). TEE revealed a high-risk source, with indication for OA in 17 of them (8.0%). A potential source leading to OA was found in an additional 48 patients (22.6%). The remaining 147 patients (69.3%) were treated by platelet inhibitors or statins.

CONCLUSIONS

TEE strongly influenced secondary prevention and led to OA in one third of our patients with stroke of undetermined etiology. TEE is indispensable in all patients being candidates for OA when routine diagnostics cannot clarify stroke etiology.

Echocardiography in stroke and the prescription of new anticoagulation and cardiac medications: A pilot project

Previous research on echocardiography in patients with acute stroke has focused on identifying possible cardioembolic etiologies of the stroke, but physicians might also obtain echocardiography to guide the management of heart disease in stroke patients. The objectives of this study were to determine how frequently echocardiography is used in acute ischemic stroke patients, and to evaluate if receiving echocardiography is associated with new prescriptions for anticoagulant or cardiac medications. This secondary data analysis of a previous cohort study included medical records of acute ischemic stroke patients admitted to 1 of 10 acute-care hospitals in Connecticut from 1996 to 1998. A total of 58 of 119 (49%) acute ischemic stroke patients received echocardiography. Among these 58 patients, 43 (74%) received either a new prescription for anticoagulation or a new cardiac medication prescription (10 of 58 [17%] new anticoagulation only, 22 of 58 [38%] new cardiac medication only, and 11 of 58 [19%] both). New anticoagulant medications were prescribed more often in patients receiving echocardiography (21 of 58; 36%), than in patients not receiving echocardiography (10 of 61; 16%) (P = .014). In addition, new cardiac medications were prescribed more often in patients receiving echocardiography (34 of 58; 59%), than in patients not receiving echocardiography (24 of 61; 39%) (P = .035). Echocardiography is commonly obtained in patients with acute stroke, and its use is associated with both the prescription of new anticoagulation and new cardiac medications. Although previous research about the use of echocardiography in acute stroke has focused on its role in identifying stroke etiologies, future research should include an assessment of it use in treating concomitant heart disease.

The recurrence risk of ischemic stroke in childhood

OBJECTIVE

To determine the risk of recurrence of ischemic stroke in children and to evaluate the influence of etiological factors and underlying mechanisms on recurrence rate.

SUBJECTS AND METHODS

Thirty-six children (21 boys and 15 girls) with clinically and radiographically proven ischemic cerebral infarction were prospectively followed up over a period of 1-9 years (median 5 years 5 months). The median age of onset of stroke was 8.4 years (1-16 years). Patients with hemorrhagic stroke, neonatal infarction and sinovenous thrombosis were not included. The patients were analyzed according to the mechanisms and etiology of the initial and recurrent stroke event.

RESULTS

For the initial stroke, cardioembolic (33.3%) and arteriopathic processes (36.1%) were identified as the most probable mechanisms of arterial ischemic stroke. Prothrombotic abnormalities were found in 4 children (11.1%). Underlying pathology in the remaining 7 (19.4%) was not known. Recurrent ischemic infarction was diagnosed in 5 children (13.9%) within 5 days to 18 months (median 6 months) after the first stroke manifestation. In 3 of them stroke recurrence was due to cardiac or transcardiac embolism. Cardiac abnormality prior to the first stroke was detected in 1 child. Clinically silent multiple cerebral infarcts disclosed by MRI preceded the overt stroke episode in 2 patients.

CONCLUSION

Congenital and acquired heart diseases were the most common cause of repeated stroke in our study. The risk of recurrence appeared to be fivefold higher in children with cardiac disease irrespective of the coexistence of other risk factors. The risk factors of stroke in children were multiple and overlapping. Consequently, recognition of the major one and its underlying mechanism is crucial for both effective therapeutic approach and the prevention of recurrence.