Sources Of Embolism In Patients Research Articles

Predicting incident atrial fibrillation in patients with embolic stroke of undetermined source

Abstract Introduction Atrial fibrillation (AF) is an important potential embolic source in patients who have suffered an embolic stroke of undetermined source (ESUS). AF has been detected in over 40% of patients when monitored with an implantable loop recorder (ILR). Recent clinical trials, however, have suggested that empirical anticoagulation of all patients with an ESUS is not an effective approach to reduce stroke risk. Thus predicting which patients are most likely to develop AF is of increased importance. Risk models for predicting incident AF exist but they do not incorporate modern techniques such as advanced echocardiographic parameters to create a comprehensive risk model. Purpose We sought to create a multi-parametric risk score for the prediction of incident AF in patients with ESUS. Methods This was a single-centre retrospective study. Consecutive adult patients referred for ILR implantation following ESUS, between March 2009 and November 2019, without prevalent AF or atrial flutter, were included. Patients’ notes were reviewed for clinical and anthropometric data. Each patients’ echo was re-reviewed both for conventional measures, and advanced parameters including left atrial strain using speckle-tracking (figure 1) and atrial electromechanical delay utilising the time from onset of the electrocardiographic P-wave to the lateral tissue Doppler A’ wave- "lateral PA". Univariate and multivariable analyses were performed, and a subsequent Lasso regression analysis used to develop a risk prediction model. Bootstrapping was used to perform internal validation. Results A total of 323 patients with ESUS who underwent a loop recorder implantation were included. Incident AF was detected in 142 patients (47.1%). Increased duration of the time between the electrocardiographic P-wave and the lateral tissue Doppler A’ wave (greater lateral PA), older age, higher diastolic blood pressure, abnormal left atrial reservoir strain were most strongly associated with increased AF risk. These were combined to form the PADS score below. Model discrimination was good, with an area under the curve of 0.72. Conclusion(s) The PADS score is a novel risk score for the prediction of incident AF in patients who have suffered an ESUS, based on the duration of the P-wave to the lateral tissue Doppler A’ wave, Age, Diastolic blood pressure and left atrial strain reservoir . Further work is required to assess whether the PADS score can be used to risk stratify patients into a high risk group which would derive benefit from immediate anticoagulation, an intermediate risk group who require prolonged continuous monitoring and a low risk group who can continue on conventional management for their stroke.PADS formulaLA strain using speckle strain analysis

Aortic arch atheroma and stroke recurrence in mild stroke patients: ADS post-hoc analysis

BackgroundAortic arch atheroma is one of the embolic sources in patients with ischemic stroke. Although transesophageal echocardiogram (TEE) is the golden standard to evaluate the aortic arch atheroma, it is invasive and may be limited to patients with suspected embolism. Present post-hoc analysis evaluated the acute dual study data on mild stroke patients who had aortic arch atheroma proven by TEE and evaluate whether combined cilostazol and aspirin therapy might reduce the rate of stroke recurrence comparing aspirin therapy. MethodsAortic arch atheroma was defined as aortic arch plaque with a maximal intima-medial thickness of ≥4.0 mm. Stroke recurrence included new diffusion-weighted image (DWI) lesions within 14 days. ResultAmong 316 (227 [72%] men; median, 66 [interquartile, 60–76] years old) patients, TEE found that 93 patients (29%) had the aortic arch atheroma, and 223 (71%) did not had it. The aortic arch atheroma group was older (P = 0.001) and accompanied with diabetes mellitus (P = 0.003), dyslipidemia (P = 0.046), smoking (P = 0.034), and had previous ischemic stroke history (P = 0.042) and multiple infarcts (P = 0.024) on admission. During hospitalization, new DWI lesion was frequently observed in the aortic arch atheroma group compared to the group without it (14.1% vs. 6.8%, P = 0.049). The rates of new DWI lesion were not different between dual antiplatelet therapy group and aspirin group (14.9% vs. 13.3%, P = 1.000). ConclusionAortic arch atheroma was the representative of systematic arteriosclerosis associated with new DWI lesion in short-term. Combined antiplatelet therapy using cilostazol did not prevent new DWI appearance comparing aspirin therapy in this cohort.

Phenotyping of embolic cryptogenic stroke based on ultrasound diagnosis and determination of serum concentration NT-proBNP

Determining the potential mechanisms underlying cryptogenic ischemic stroke is essential to guide diagnostic discovery and personalize secondary prevention.Purpose is to study the phenotypes of embolic stroke of undetermined source (ESUS) based on ultrasound diagnosis and determination of the serum concentration of pro-natriuretic N-terminal peptide B-type (N-Terminal Pro-brain Natriuretic Peptide, NT-proBNP).Materials and methods. 141 patients with ESUS were examined. In addition to the standard examination aimed at fi nding the cause of stroke, the functional characteristics of the left atrium were assessed using the emptying fraction (left atrial emptying fraction, LAEF) and the functional index (left atrial function index, LAFI), and the concentration of NT-proBNP in blood serum was also measured.Results. The most common potential sources of embolism were atherosclerotic plaques in the stroke-associated carotid artery with stenosis in 30–49% (31.9% of patients) and atrial cardiopathy with a decrease in LAEF < 51.8% (24.8% of patients). An analysis of combinations of potential sources showed that 46.1% of patients had a negative phenotype, 21.3% of patients had a cardiac phenotype, 19.1% of patients had an atherosclerotic phenotype, and 13.5% of the examined patients had a mixed phenotype. Patients with a cardio-atherosclerotic phenotype diff ered from patients with a negative phenotype by higher disability on the Rankin scale at discharge from the hospital.Conclusion. The main potential embolic sources in patients with ESUS are non-stenosing carotid atherosclerosis and atrial cardiopathy with decreased LAEF. Cardiac and atherosclerotic phenotypes are determined in a quarter of patients, a mixed phenotype is found in every seventh patient, while in almost half of the patients no sources of embolism are found.

Het nut van implanteerbare looprecorders na een embolische beroerte van ongekende oorsprong

The use of implantable loop recorders after embolic stroke of undetermined source Unknown intermittent atrial fibrillation (AF) is a potential source of embolism in patients with embolic stroke of undetermined source (ESUS). Prolonged heart rhythm monitoring with implantable loop recorders (ILR) could increase the detection of AF. Patients with detected (subclinical) AF may benefit from a therapy with anticoagulants after ESUS. The authors of this article performed a retrospective analysis of patients who received an ILR after suspected ESUS at the University Hospitals of Leuven (Belgium) between April 2008 and March 2019. They describe the proportion of patients in whom AF was detected and studied the predictors of AF detection. With prolonged monitoring, the AF detection rate increased, mainly in the first 2 years after implantation. AF was detected in 28 out of 84 patients (33.3%) after a median follow-up of 8 months. Patients with AF were significantly older and tended to have more arterial hypertension. All patients with detected AF received oral anticoagulation. Although a 24-hour Holter monitoring and a week recorder were negative for AF detection, an ILR established (subclinical) AF in 1 out of 3 patients after ESUS.

Routine left atrial appendage occlusion in patients undergoing cardiac surgery: a narrative review.

New evidence suggests a greater prevalence of protracted postoperative atrial fibrillation (POAF) than previously recognized. The left atrial appendage (LAA) is the most common source of embolism in patients with nonvalvular atrial fibrillation. In this review, we ask whether there is evidence to support routine LAA occlusion (LAAO) in patients without preexisting atrial fibrillation undergoing cardiac surgery. Overall, available studies are small, inconsistent and have varying proportions of patients with and without preexisting atrial fibrillation. There is considerable discrepancy with respect to the efficacy of LAAO in reducing the risk of POAF-related stroke. Only one study reported a lower rate of stroke in the LAAO group compared with no LAAO. Two studies included a subgroup analysis of patients that developed POAF and report a significantly higher rate of stroke in patients that developed POAF and did not undergo LAAO. There are three clinical trials ongoing that are investigating prophylactic LAAO in patients undergoing cardiac surgery: ATLAS, LAA-CLOSURE and LAACS-2. There is currently insufficient evidence to recommend routine addition of LAAO to lower the risk of postoperative stroke. Ongoing clinical trials will provide important insight into the role of routine LAAO in all patients undergoing cardiac surgery.

Detection and prevalence of intra-cardiac thrombus in patients with embolic stroke of undetermined source

Abstract Background Embolic Stroke of Undetermined Source (ESUS) is defined as non-lacunar brain infarct without proximal arterial stenosis or known cardioembolic source (including atrial arrythmias). Little is known about the prevalence of intra-cardiac thrombus as a potential source of embolism in patients presenting with ESUS. Objectives To examine the use of contrast-enhanced electrocardiogram-gated computed tomography (CT) to elucidate the prevalence of intra-cardiac thrombus in patients suspected of ESUS. Methods We retrospectively investigated 101 consecutive patients who presented to our hospital with ESUS between January 2019 and March 2021 and underwent 2D echocardiography and CT as part of stroke etiology evaluation. Results In our study population (73.2±9.98 years, 41% female), CT detected intra-cardiac thrombus in 19 (18.8%) patients. Left ventricular thrombus (LVT) was found in 10 (9.9%) patients and left atrial/left atrial appendage in 8 patients. All of cases of LVT were detected by cardiac CT, while 2D echocardiography was able to detect only four of these cases. All cases of LVT were associated with significant coronary obstructive disease, while in 2 out of 10 patients, a previous history of ischemic heart disease was unknown. Using CT 2 patients after transcatheter aortic valve implantation were diagnosed with hypoattenuated leaflet thickening, and 3 patients with concomitant pulmonary embolism. In total, the finding of CT resulted in change of management, indication for anticoagulation instead of antiplatelets drugs, in 23 (22.7%) patients. Conclusion CT may help to improve the detection of intra-cardiac thrombus in patients presenting with ESUS and therefore provide relevant information for anticoagulation therapy and need of further coronary evaluation and intervention. The high prevalence of intra-cardiac thrombus in ESUS patients make the use of complementary 3D imaging important. Funding Acknowledgement Type of funding sources: None.

Carotid webs in large vessel occlusion stroke: Clinical, radiological and thrombus histopathological findings

BackgroundCarotid webs are an under-recognized embolic source in patients with cryptogenic stroke. Limited resources currently exist to assist clinicians in stroke prevention for patients with symptomatic carotid webs (SCW). We aimed at analysing the clinical, radiological and procedural features of stroke patients with SCW undergoing endovascular thrombectomy (EVT), and to describe the histopathological composition of their occlusive thrombi. MethodsIn a single-center observational study on consecutive patients with ischemic stroke treated by EVT, carotid web was defined symptomatic when it was ipsilateral to the ischemic lesion in a patient classified with stroke of otherwise undetermined etiology. Clinical, radiological and procedural data of patients with SCW were evaluated. Histopathological examination of the retrieved thrombi was performed. ResultsOut of 1430 patients with large vessel occlusion stroke treated by EVT, 11(0.7%) were found to have a SCW. Patients with SCW had a median age of 47 years old (IQR 38–50), they were prevalently women (55%), mostly of African ethnicity (91%). Each of the 11 patients achieved successful angiographic reperfusion (mTICI 2b-3) after EVT. For secondary prevention, elective endovascular carotid stenting was performed in 5 (55%) patients, while 1 (9%) was treated by surgical endoarterectomy. Histological analysis of the retrieved thrombi performed in 4 patients showed a mixed composition with variable red blood cell content. ConclusionsEVT is feasible in large vessel occlusion stroke related to SCW. Procedures of carotid revascularization appear to be feasible therapeutic options for secondary prevention. The histopathological analysis of cerebral thrombi may provide new insights on stroke pathogenesis in patients with SCW.

Editors' note: Undetermined stroke genesis and hidden cardiomyopathies determined by cardiac magnetic resonance

In “Undetermined stroke genesis and hidden cardiomyopathies determined by cardiac magnetic resonance,” Fonseca et al. reported a higher frequency of cardiomyopathies identified on cardiac MRI in patients with ischemic stroke than in the general population, particularly among patients with stroke of undetermined etiology. Lattanzi and Silvestrini commended the authors' contribution to our understanding of embolic strokes of undetermined source (ESUS). To learn more about this patient population, Lattanzi and Silvestrini recommended a thorough review of data on demographics, stroke severity, and location and evaluation for embolic sources in patients with ESUS to assess for the presence of unique phenotypes that would benefit from specific diagnostic algorithms and therapeutic approaches. Fonseca and Ferro agreed with the need for further evaluation of this patient population and, based on their findings, recommended increased use of cardiac MRI. However, they noted that it is not feasible to do this for all patients with ESUS and acknowledged the need to clarify which patients would benefit from it the most. In “Undetermined stroke genesis and hidden cardiomyopathies determined by cardiac magnetic resonance,” Fonseca et al. reported a higher frequency of cardiomyopathies identified on cardiac MRI in patients with ischemic stroke than in the general population, particularly among patients with stroke of undetermined etiology. Lattanzi and Silvestrini commended the authors' contribution to our understanding of embolic strokes of undetermined source (ESUS). To learn more about this patient population, Lattanzi and Silvestrini recommended a thorough review of data on demographics, stroke severity, and location and evaluation for embolic sources in patients with ESUS to assess for the presence of unique phenotypes that would benefit from specific diagnostic algorithms and therapeutic approaches. Fonseca and Ferro agreed with the need for further evaluation of this patient population and, based on their findings, recommended increased use of cardiac MRI. However, they noted that it is not feasible to do this for all patients with ESUS and acknowledged the need to clarify which patients would benefit from it the most.

Carotid Atherosclerosis and Patent Foramen Ovale in Embolic Stroke of Undetermined Source

BackgroundCarotid atherosclerosis and likely pathogenic patent foramen ovale (PFO) are two potential embolic sources in patients with embolic stroke of undetermined source (ESUS). The relationship between these two mechanisms among ESUS patients remains unclear. AimTo investigate the relation between carotid atherosclerosis and likely pathogenic PFO in patients with ESUS. We hypothesized that ipsilateral carotid atherosclerotic plaques are less prevalent in ESUS with likely pathogenic PFO compared to patients with likely incidental PFO or without PFO. MethodsThe presence of PFO was assessed with transthoracic echocardiography with microbubble test and, when deemed necessary, through trans-oesophageal echocardiography. The presence of PFO was considered as likely incidental if the RoPE (Risk of Paradoxical Embolism) score was 0–6 and likely pathogenic if 7–10. ResultsAmong 374 ESUS patients (median age: 61years, 40.4% women), there were 63 (49.6%) with likely incidental PFO, 64 (50.4%) with likely pathogenic PFO and 165 (44.1%) with ipsilateral carotid atherosclerosis. The prevalence of ipsilateral carotid atherosclerosis was lower in patients with likely pathogenic PFO (7.8%) compared to patients with likely incidental PFO (46.0%) or patients without PFO (53.0%) (p<0.001). After adjustment for multiple confounders, the prevalence of ipsilateral carotid atherosclerosis remained lower in patients with likely pathogenic PFO compared to patients with likely incidental PFO or without PFO (adjusted OR=0.32, 95%CI:0.104-0.994, p=0.049). ConclusionsThe presence of carotid atherosclerosis is inversely related to the presence of likely pathogenic PFO in patients with ESUS.

Atrial Cardiopathy and Likely Pathogenic Patent Foramen Ovale in Embolic Stroke of Undetermined Source.

Atrial cardiopathy and likely pathogenic patent foramen ovale (PFO) are two potential embolic sources in patients with embolic stroke of undetermined source (ESUS). The relationship between these two mechanisms among ESUS patients remains unclear. Atrial cardiopathy was defined as increased left atrial diameter index (> 23 mm/m2) or left atrial volume index (> 34 mL/m2), or PR prolongation (≥ 200 ms), or presence of supraventricular extrasystoles in the electrocardiograms performed during hospitalization for the index stoke. The presence of PFO was assessed by transthoracic echocardiography with microbubble test or by transesophageal echocardiography. The presence of PFO was considered as likely pathogenic if the Risk of Paradoxical Embolism score was 7 to 10. Among 367 ESUS patients with available information about the presence of PFO and the presence of atrial cardiopathy (median age: 61 years, 40.6% women), likely pathogenic PFO was diagnosed in 62 (16.9%) and atrial cardiopathy in 122 (33.2%). Only 4 patients (1.1%) had both likely pathogenic PFO and atrial cardiopathy. The prevalence of atrial cardiopathy was lower in patients with likely pathogenic PFO (6.5%) compared with patients with likely incidental PFO (31.2%) or without PFO (40.6%) (Pearson's chi-square test: 26.08, p < 0.001; adjusted odds ratio [OR]: 0.28, 95% confidence interval [CI]: 0.09-0.86). The prevalence of likely pathogenic PFO was lower in patients with atrial cardiopathy compared with patients without atrial cardiopathy (3.3% vs. 23.7%, respectively [Pearson's chi-square test: 24.13, p < 0.001; adjusted OR: 0.2, 95% CI: 0.02-0.6]). The presence of atrial cardiopathy is inversely related to the presence of likely pathogenic PFO in patients with ESUS.

Minimally invasive, simplified double-layer left atrial appendage closure.

The left atrial appendage (LAA) has been identified as a site of thrombus formation in the heart and as a source of embolism in patients with atrial fibrillation, leading to stroke. Studies suggest that LAA closure may reduce the risk for stroke and the need for anticoagulation; conversely, incomplete closure can increase the stroke risk almost 12-fold. Because open heart surgery is associated with increased risk for subsequent stroke, surgeons generally prefer to close the LAA during heart surgery, as recommended in current atrial fibrillation management guidelines. Building on trends toward minimally invasive approaches in cardiac surgery, we developed a simple, unique, and reproducible method for complete LAA closure during mitral valve surgery that has proven to be safe and efficacious: Our first three patients remained completely free from stroke and minor neurological manifestations 27 months after surgery.

Editors' note: Atrial cardiopathy in patients with embolic strokes of unknown source and other stroke etiologies

In the article “Atrial cardiopathy in patients with embolic strokes of unknown source and other stroke etiologies,” Jalini et al. reported atrial cardiopathy in 26.6% of patients meeting the criteria for embolic stroke of unknown source (ESUS) vs 12.1% of patients with large artery atherosclerosis and 16.9% of those with small vessel disease in a cross-sectional study of 846 consecutive patients with ischemic stroke. They also found that patients with ESUS were younger, less hypertensive, and had higher cholesterol and low-density protein levels but fewer left ventricular or atrial abnormalities compared with yet another group with cardioembolism. In response, Drs. Lattanzi and Silvestrini note that they recently found an inverse association between abnormally increased P-wave terminal force in lead V1 (a marker of atrial cardiopathy) and paradoxical or artery-to-artery embolic sources in patients with ESUS. Patients with anterior circulation ESUS more often had ipsilateral (vs contralateral) internal carotid artery plaques with more concerning atherosclerotic findings, whereas younger patients with ESUS had higher incidence of patent foramen ovale (PFO) and lower rates of other vascular risk factors or markers of cardiopathy or atherosclerosis. Stating that ESUS is thus a heterogeneous entity, they encourage the identification of such distinct phenotypes to help guide secondary prevention and potentially targeted interventions. In their reply, the authors agree that the ESUS definition seems too broad and that factors such as PFO, aortic arch, and nonstenotic carotid plaques that were not addressed in their study are important embolic sources in subgroups of patients with ESUS. They note that ongoing trials in subgroups of patients with ESUS will further inform secondary prevention in this population. In the article “Atrial cardiopathy in patients with embolic strokes of unknown source and other stroke etiologies,” Jalini et al. reported atrial cardiopathy in 26.6% of patients meeting the criteria for embolic stroke of unknown source (ESUS) vs 12.1% of patients with large artery atherosclerosis and 16.9% of those with small vessel disease in a cross-sectional study of 846 consecutive patients with ischemic stroke. They also found that patients with ESUS were younger, less hypertensive, and had higher cholesterol and low-density protein levels but fewer left ventricular or atrial abnormalities compared with yet another group with cardioembolism. In response, Drs. Lattanzi and Silvestrini note that they recently found an inverse association between abnormally increased P-wave terminal force in lead V1 (a marker of atrial cardiopathy) and paradoxical or artery-to-artery embolic sources in patients with ESUS. Patients with anterior circulation ESUS more often had ipsilateral (vs contralateral) internal carotid artery plaques with more concerning atherosclerotic findings, whereas younger patients with ESUS had higher incidence of patent foramen ovale (PFO) and lower rates of other vascular risk factors or markers of cardiopathy or atherosclerosis. Stating that ESUS is thus a heterogeneous entity, they encourage the identification of such distinct phenotypes to help guide secondary prevention and potentially targeted interventions. In their reply, the authors agree that the ESUS definition seems too broad and that factors such as PFO, aortic arch, and nonstenotic carotid plaques that were not addressed in their study are important embolic sources in subgroups of patients with ESUS. They note that ongoing trials in subgroups of patients with ESUS will further inform secondary prevention in this population.

Etiology of Cryptogenic Stroke

Ischemic stroke is a heterogeneous syndrome with a plurality of potential etiological factors. The routine diagnosis does not always allow the cause of acute cerebrovascular accident to be found, in such cases we talk about cryptogenic ischemic stroke, which incidence is 20-40%. The category of patients with cryptogenic stroke was first characterized and assigned to a separate group in the database of the National Institute of Neurological Diseases and Stroke in the USA, and later in the TOAST study. The diagnosis of cryptogenic stroke is usually based on the exclusion of well-known causes of acute cerebrovascular accidents, such as atherosclerosis, cardiac arrhythmias, arterial hypertension. Due to the considerable variability of concepts for cryptogenic stroke, the term ESUS (Embolic Stroke of Undetermined Source) appeared in 2014 and formulated criteria which accurately characterized these patients: non-lacunar cerebral infarction by CT and/or MRI, no atherosclerotic lesion stenosing a stroke-associated artery of more than 50%, no sources of high-risk cardioembolism, no other causes of stroke such as dissection of the artery supplying the area of infarction in the brain, migraine, arteritis. Among the potential causes and sources of cerebral embolism in patients with cryptogenic stroke are heart, veins of lower extremities and pelvis, nonstenosing atherosclerosis of brachiocephalic artery, atheroma of aortic arch, paradoxical embolism non-atherosclerotic vasculopathy, monogenic diseases, hypercoagulable states, and others. We should note that there is a lot of studies on the possible causes of cryptogenic stroke in the available literature, but no common approach to classification of etiologic factors and examination algorythms were developed. The high incidence of cryptogenic stroke, the significant heterogeneity of its etiopathogenetic mechanisms and the need for differentiated approaches to the secondary prevention of this type of acute cerebrovascular accident determine the relevance of further studies in this field.

Prevalence and Overlap of Potential Embolic Sources in Patients With Embolic Stroke of Undetermined Source.

BackgroundWe aimed to assess the prevalence and degree of overlap of potential embolic sources (PES) in patients with embolic stroke of undetermined source (ESUS).Methods and ResultsIn a pooled data set derived from 3 prospective stroke registries, patients were categorized in ≥1 groups according to the PES that was/were identified. We categorized PES as follows: atrial cardiopathy, atrial fibrillation diagnosed during follow‐up, arterial disease, left ventricular disease, cardiac valvular disease, patent foramen ovale, and cancer. In 800 patients with ESUS (43.1% women; median age, 67.0 years), 3 most prevalent PES were left ventricular disease, arterial disease, and atrial cardiopathy, which were present in 54.4%, 48.5%, and 45.0% of patients, respectively. Most patients (65.5%) had >1 PES, whereas only 29.7% and 4.8% of patients had a single or no PES, respectively. In 31.1% of patients, there were ≥3 PES present. On average, each patient had 2 PES (median, 2). During a median follow‐up of 3.7 years, stroke recurrence occurred in 101 (12.6%) of patients (23.3 recurrences per 100 patient‐years). In multivariate analysis, the risk of stroke recurrence was higher in the atrial fibrillation group compared with other PES, but not statistically different between patients with 0 to 1, 2, or ≥3 PES.ConclusionsThere is major overlap of PES in patients with ESUS. This may possibly explain the negative results of the recent large randomized controlled trials of secondary prevention in patients with ESUS and offer a rationale for a randomized controlled trial of combination of anticoagulation and aspirin for the prevention of stroke recurrence in patients with ESUS.Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02766205.

The sources of emboli in patients with pulmonary embolism diagnosed by autopsy

Objective: To study the sources of emboli in patients with pulmonary embolism diagnosed by autopsy, and therefore to provide help in the diagnosis and treatment of thromboembolism. Methods: We retrospectively analyzed the pathology and clinical data of 43 patients with pulmonary embolism diagnosed by autopsy from 1962 to 2012 in Beijing Hospital. Results: In patients with pulmonary embolism diagnosed by autopsy, 32.6% of the emboli came from deep veins of the lower extremities, 9.3% from the renal vein, 9.3% from the prostate sinus, 7.0% from the venous plexus around the prostate, 7.0% from the hepatic vein and 7.0% from the submucosal vein of the bladder. Other sources included the right atrium 4.7%, portal vein 4.7%, pancreatic peripheral vein 4.7%, prostate, heart, esophageal vein 4.7%, right common iliac vein 2.3%, right upper limb brachial vein 2.3%. No source of emboli was found in 4.7% patients with pulmonary embolism. Non-lower extremity deep vein emboli accounted for 60.5%. Only 9.3% of the cases were diagnosed with pulmonary embolism with deep vein thrombosis before death. Conclusion: There was a wide range of sources of emboli in patients with pathologically proven pulmonary embolism. Although the deep veins of lower extremities are the most common, more than 60% of the emboli came from the renal vein, prostate vein, hepatic vein and other abdominal or pelvic veins, the heart, and the upper extremity deep veins. In addition to the lower extremity deep veins, other sources of emboli should be actively examined when the patient was diagnosed with acute pulmonary embolism.

Left atrial myxoma causing posterior cerebral artery infarct-a case report

A 34-year-old female patient presented with a history of sudden loss of vision in right eye. On neurological examination, she was having visual agnosia in right eye. MRI was performed which revealed left posterior cerebral artery infarct. Trans thoracic echocardiography was performed. This showed a large left atrial myxoma. Patient underwent resection and had an uneventful postoperative course. This case report showed the importance of cardiac source of emboli in patients presenting as acute stroke. Performing echocardiography and diagnosing and treating cardiac source of emboli could prevent further complications.

Abstract TMP46: Computed Tomography of Non-Stenotic Carotid Plaque in Patients with Embolic Stroke of Undetermined Source (ESUS)

Introduction: In up to 25% of patients with an ischemic stroke, the standard investigations fail to identify a cause. Many of these cryptogenic strokes are thromboembolic, but without an established source, so called “embolic strokes of undetermined source” (ESUS). Non-stenotic carotid plaque is a potential source. Hypothesis: We hypothesized that among patients with ESUS, there is an association between non-stenotic carotid atherosclerotic plaque diagnosed using CT angiography and ipsilateral ischemic stroke. Methods: From a prospectively maintained stroke registry, we identified consecutive patients between January 2012 and March 2015 with a carotid territory ischemic stroke, who fulfilled the diagnostic criteria for ESUS. Two radiologists, blinded to clinical information, independently measured carotid plaque thickness ipsilateral and contralateral to the ischemic stroke using CT angiography. Results: Eighty-five of 1038 ischemic stroke patients were included in the analysis. There was no difference in the degree of carotid artery stenosis ipsilateral versus contralateral to ischemic stroke (median 0% versus 0%, p=0.98). There was a weak correlation between degree of carotid artery stenosis and carotid plaque thickness (R2 = 0.26, p&lt;0.001). Plaque thickness ≥ 5 mm (9/85 versus 1/85, p=0.008), ≥ 4 mm (16/85 versus 4/85, p=0.002), and ≥ 3 mm (30/85 versus 13/85, p=0.001) were each more common ipsilateral than contralateral to ischemic stroke. Plaque thickness ≥ 2 mm had the same frequency ipsilateral and contralateral to ischemic stroke. Conclusions: Our data suggest that large, non-stenotic carotid plaque may be an important source of embolism in patients with ESUS. We evaluated non-stenotic plaque using routine CT angiography, a method that could be easily translated into clinical practice.

Complex atheromatous plaques in the descending aorta and the risk of stroke: a systematic review and meta-analysis.

Proximal aortic plaques, especially in the aortic arch, have already been established as an important cause of stroke and peripheral embolism. However, aortic plaques situated in the descending thoracic aorta have recently been postulated as a potential embolic source in patients with cryptogenic cerebral infarction through retrograde aortic flow. The aim of the present study was to evaluate the potential association of descending aorta atheromatosis with cerebral ischemia. We conducted a systematic review and meta-analysis of all available prospective observational studies reporting the prevalence of complex atheromatous plaques in the descending aorta in patients with stroke and in unselected populations undergoing examination with transesophageal echocardiography. We identified 11 eligible studies including a total of 4000 patients (667 patients with stroke and 3333 unselected individuals; mean age, 65 years; 55% men). On baseline transesophageal echocardiograpic examination, the prevalence of complex atheromatous plaques in the descending aorta was higher (P=0.001) in patients with stroke (25.4%; 95% confidence interval, 14.6-40.4%) compared with unselected individuals (6.1%; 95% confidence interval, 3.4-10%). However, no significant difference (P=0.059) in the prevalence of complex atheromatous plaques in the descending aorta was found between patients with cryptogenic (21.8%; 95% confidence interval, 17.5-26.9%) and unclassified (28.3%; 95% confidence interval, 23.9-33.1%) cerebral infarction. Our findings indicate that the presence of complex plaques in the descending aorta is presumably a marker of generalized atherosclerosis and high vascular risk. The present analyses do not provide any further evidence for a direct causal relationship between descending aorta atherosclerosis and cerebral embolism.

Abstract T P170: Risk Stratification in Acute Ischemic Stroke by Transcranial Doppler in a Multiethnic Population: Role of Microembolic Signal

Background: The role of microembolic signal (MES) detected by transcranial Doppler sonography in the acute phase of a stroke remains controversial in the medical literature. The prevalence of MES in the various sources of arterial brain embolism in patients in developing countries has been poorly studied. We investigated the prevalence of MES and whether MES detection is of proven use for risk stratification in the Brazilian population Methods: This was a transversal study with 45 ischemic stroke patients in acute phase at the Stroke Unit in a Brazilian hospital. All patients underwent monitoring of the middle cerebral arteries by transcranial doppler for at least 30 minutes. The examiner who conducted the monitoring was unaware of the risk stratification of the patient(single blinded). Then the record of the examination was independently analyzed by two neurologists to identify the MES. Prior to monitoring, risk stratification was carried out for all patients by complementary examinations. The independent variables were: age, NIHSS at admission, time of ictus, symptomatic carotid disease (stenosis &gt; 60%), atrial fibrillation, intracranial stenosis, diseases of small arteries and other cardioembolic sources. The outcome was the presence or absence of MES with independent variables. The relationship between admission variables and MES was analyzed by Fisher’s Exact Test and logistic regression to estimate the odds ratio with significance defined as p&lt;0.05. Results: The prevalence of MES was 10%. A significant correlation was found between ictus &lt; 24 hours before transcranial Doppler examination (p=0.04; OR=5.0) and symptomatic carotid disease (p=0.03; OR=15.6) with presence of MES. There was no statistical correlation between age (p=1.0), intracranial stenosis (p=1.0), atrial fibrillation (p=0.55), diseases of small arteries (p=0.56), other cardioembolic sources (p=0.55), and the association with atrial fibrillation and symptomatic carotid disease (p=1.0). Conclusions: MES detection showed higher correlation with symptomatic carotid disease and the precocity of monitoring in relation to time of ictus too. There was no relationship found between cardioembolic source and atrial fibrillation.

Comparison of the Effect on Right Atrial Pressure of Abdominal Compression Versus the Valsalva Maneuver

When the right atrial pressure (RAP) exceeds the left atrial pressure, right-to-left shunting can occur. Normally, the Valsalva maneuver is used to facilitate elevation of RAP. However, performing the Valsalva maneuver can be problematic in certain situations. The aim of this study was to test the hypothesis that the application of abdominal pressure would increase the pressure within the right atrium compared with the left atrium, making it an adequate alternative to the Valsalva maneuver. Twelve patients were prospectively evaluated during right-sided cardiac catheterization with the application of abdominal pressure as well as a Valsalva maneuver. RAP and left atrial pressure were measured simultaneously. In 11 patients, the mean RAP was lower than the mean pulmonary capillary wedge pressure at baseline. The mean RAP was significantly higher than the mean pulmonary capillary wedge pressure during abdominal compression (24.8 ± 9.9 vs 21.6 ± 8.8 mm Hg, p = 0.001). When the Valsalva maneuver was performed, mean RAP was also significantly higher than the mean pulmonary capillary wedge pressure (25.3 ± 10.9 vs 22.1 ± 10.3 mm Hg, p = 0.008). In conclusion, abdominal compression is similar to an optimal Valsalva maneuver for increasing RAP and thus the right-to-left pressure gradient. Performing abdominal compression provides a simple alternative to the Valsalva maneuver for creating a transient increase in RAP.