Risk Factor For Systemic Embolism Research Articles

Stroke in Atrial Fibrillation and Other Atrial Dysrhythmias.

Atrial fibrillation (AF) is a major risk factor for systemic embolism and ischaemic stroke. Furthermore, AF-related strokes are associated with higher mortality, greater disability, longer hospital stays and lower rates of hospital discharge than strokes caused by other reasons. The aim of this review to summarise the existing evidence on the association of AF with ischemic stroke and provide insights on the pathophysiological mechanisms and the clinical management of patients with AF in order to reduce the burden of ischemic stroke. Beyond Virchow's triad, several pathophysiological mechanisms associated with structural changes in the left atrium, which may precede the identification of AF, may contribute to the increased risk of arterial embolism in AF patients. Individualised thromboembolic risk stratification based on CHA2DS2-VASc score and clinically relevant biomarkers provides essential tool towards a personalised holistic approach in thromboembolism prevention. Anticoagulation remains the cornerstone of stroke prevention moving from vitamin K antagonists (VKA) to safer non-vitamin K direct oral anticoagulants in the majority of AF patients. Despite the efficacy and safety of oral anticoagulation, still the equilibrium between thrombosis and haemostasis in AF patients remains suboptimal and future directions in anticoagulation and cardiac intervention may provide novel treatment options in stroke prevention. This review summarises the pathophysiologic mechanisms of thromboembolism, aiming the current and potential future perspectives in stroke prevention in AF patients.

Analysis of factors related to systemic embolism in patients≥75 years old with non-valvular atrial fibrillation

Objective: To explore the related risk factors for systemic embolism (SE) in patients aged≥75 years with non-valvular atrial fibrillation (NVAF). Methods: A case-control study. NVAF patients aged≥75 years who were hospitalized at the First Affiliated Hospital of Xinjiang Medical University from October 2018 to October 2020 were divided into no SE (n=1 127) and SE (n=433) groups according to the occurrence of SE after NVAF. Multivariate logistic regression was used to analyze SE-related factors in patients with NVAF without anticoagulation treatment. Results: In the multivariate model, the following factors were associated with an increased risk of SE in patients with NVAF: history of AF≥5 years [odds ratio (OR)=2.75, 95% confidence interval (CI) 1.98-3.82, P<0.01], lipoprotein(a)>300 g/L (OR=2.07, 95%CI 1.50-2.84, P<0.01), apolipoprotein (Apo)B>1.2 g/L (OR=1.91, 95%CI 1.25-2.93, P=0.003), left ventricular ejection fraction (LVEF) of 30%-49% (OR=2.45, 95%CI 1.63-3.69, P<0.01), left atrial diameter>40 mm (OR=1.54, 95%CI 1.16-2.07, P=0.003), and CHA2DS2-VASc score≥3 (OR=15.14, 95%CI 2.05-112.13, P=0.01). ApoAI>1.6 g/L was negatively correlated with the occurrence of SE (OR=0.28, 95%CI 0.15-0.51, P<0.01). Conclusions: History of AF≥5 years, lipoprotein(a)>300 g/L, elevated ApoB, left atrial diameter>40 mm, LVEF of 30%-49%, and CHA2DS2-VASC score≥3 are independent risk factors for SE whereas ApoAI>1.6 g/L is a protective factor against SE in patients with NVAF.

P1312 Implications of a large atrial roof thrombus

Abstract Funding Acknowledgements No funding Introduction Rheumatic heart disease is the most common cause of mitral valve stenosis. Rheumatic valve disease presents a strong predisposing factor to intracardiac thrombi formation in the left atrium, particularly when there is a background of atrial fibrillation. The predominant location for thrombus creation is the left atrial appendage, due to its morphology, and rarely the free wall or roof of the left atrium. In either case, the presence of intracardiac thrombi in the left cardiac cavities poses a severe risk factor for systemic embolism which can prove detrimental for the patient leading to increased morbidity and mortality. Transesophageal echocardiography remains the gold standard for screening of the left atrium. Case presentation We present the case of a 72 year old woman who was admitted to the Emergency Department of our Hospital because of palpitations and progressive weakness over the last month. She had a known history of rheumatic mitral valve stenosis and chronic atrial fibrillation under standard anticoagulant treatment with acenocoumarol. Methods - Results: On admission, the patient was hemodynamically stable without signs of heart failure. The electrocardiogram revealed atrial fibrillation with a ventricular rate of approximately 135 bpm. Chest X-Ray did not demonstrate any signs of pulmonary congestion. Blood tests were normal, except from a subtherapeutic INR 1.3. Transthoracic echocardiography depicted a suspicious large echogenous mass located on the posterior wall of the left atrium. Furthermore, there was severe mitral valve stenosis with calcification of the mitral annulus as well as reduced mobility of the leaflets (Mitral Valve Area ∼0.8 cm2, Mean gradient = 15 mmHg) and mild aortic valve stenosis. The left ventricle had normal dimensions and good overall systolic function. Systolic pulmonary pressure was estimated at 50 mmHg. Transesophageal echocardiography confirmed the presence of a large echogenous mass (2,6 x 2,9 cm) located on the posterior wall of the left atrium between the right and left pulmonary veins as well as another mass at the left atrial appendage. Contrast echocardiography ensued, which revealed no absorption of the contrast medium by the mass thus suggesting a lesion with no vascularity, compatible with thrombus. Furthermore there was diffuse slow flow within the left atrium (smoke) indicating blood stasis. The patient was treated with a cardioselective beta blocker and combination of aspirin and acenocoumarol with a target INR of 2,5-3 and was referred for cardiothoracic consultation. Conclusion/Discussion: We describe a rare case of moderate mitral stenosis with presence of a large thrombus with mobile parts in an unusual location. In this setting the indication for surgery (mitral valve replacement) is upgraded since there is increased risk of thrombus detachment and debilitating systemic embolism. Abstract P1312 Figure.

Abstract TP231: Echocardiographically Identified Left Atrial Enlargement is Associated With Non-valvular Paroxysmal Atrial Fibrillation (PAF) and is a Surrogate for PAF Associated Risk for Embolic Stroke

Introduction: Paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation are risk factors for systemic embolism including stroke. Both are indication for anticoagulation. Many patients with stroke in sinus rhythm are shown on ambulatory ECG monitoring to have PAF. PAF is difficult to diagnose on ambulatory ECG monitoring. A persistent marker for PAF will be useful to identify need for anticoagulant to reduce stroke risk due to PAF. Echocardiographic variable with a high predictive value for PAF is desirable. Objective: The purpose of the study was to investigate the relationship between left atrial (LA) size and proneness to paroxysmal atrial fibrillation and assess its reliability as a surrogate for diagnosing non valvular PAF. Method: Echo Database for patients with measured LA volume index, in sinus rhythm without history of intervention for atrial fibrillation, pharmacological therapy, and cardioversion or ablation therapy over a seven year period was reviewed. Patients with enlarged LA Volume index (&gt;28ml/M 2 ) were selected. Seven Day ambulatory ECG monitoring was performed in these patients, ResultEchocardiogram data of 245 patients were available for analysis. 41 had greater than mild mitral valve regurgitation and were excluded from further analysis. Age range was 37-93. 99 were male. 211 patients had LA volume index data available. In 8 patients in sinus rhythm on ambulatory ECG, LA volume index was mildly increased (28-34 ml/M 2) In 16 patients with PAF on ambulatory ECG, LA volume index was mildly increased (28-34 ml/M 2 ) In 100 patients with PAF on ambulatory ECG, LA volume index was moderately increased (35-40 ml/M 2 ) In 88 patients with PAF on ambulatory ECG, LA volume index was severely increased (&gt;40 ml/M 2 ) Conclusion: In patients with moderately and severely enlarged LA volume index, there was a high prevalence of paroxysmal atrial fibrillation on ambulatory ECG monitoring. Left Atrial volume index could serve as an echocardiographic surrogate for PAF and identify indication for anticoagulation to reduce stroke risk. It Is More Easily Identifiable Surrogate For PAF Than Ambulatory ECG Monitoring In Stroke Risk Assessment.

Are direct oral anticoagulants effective in reducing systemic embolism in patients with atrial fibrillation? A systematic review and meta-analysis of the literature

Atrial fibrillation (AF) is the most prevalent sustained heart arrhythmia. It is the most important clinical risk factor for systemic embolism (SE) and is regarded to be the cause of stroke in up to one fourth of cases [ [1] Grau A.J. Weimar C. Buggle F. Heinrich A. Goertler M. Neumaier S. Glahn J. Brandt T. Hacke W. Diener H.C. Risk factors, outcome, and treatment in subtypes of ischemic stroke: the German stroke data bank. Stroke. 2001; 32: 2559-2566 Crossref PubMed Scopus (730) Google Scholar ]. However, since stroke is much more prevalent than SE in patients with AF, the latter is not considered to be a main single outcome parameter in AF trials. As a consequence, the majority of trials on the role of anticoagulants in AF patients have focused over stroke prevention, and SE has been included only as a part of composite end-points. Thus, the superiority of warfarin compared to antiplatelet agents in preventing non-cerebral embolism has been proven only in a recent meta-analysis [ [2] Andersen L.V. Vestergaard P. Deichgraeber P. Lindholt J.S. Mortensen L.S. Frost L. Warfarin for the prevention of systemic embolism in patients with non-valvular atrial fibrillation: a meta-analysis. Heart. 2008; 94: 1607-1613 Crossref PubMed Scopus (60) Google Scholar ]. European and US guidelines currently recommend oral anticoagulants over antiplatelet agents for stroke prevention in AF, and these indications are thought to be applicable also for prevention of SE.

Abstract 18597: Systemic, Non-cerebral, Arterial Embolism in 21,105 Patients with Atrial Fibrillation Randomized to Edoxaban or Warfarin: Results from the ENGAGE AF-TIMI 48 Trial

Background: Atrial fibrillation (AF) is widely recognized as a major risk factor for stroke and systemic embolism. Multiple trials comparing warfarin with factor specific oral anticoagulants have demonstrated that the newer agents are at least as effective as and generally safer than warfarin. However, none of these studies has provided a detailed analyses regarding systemic embolism, the less frequent component of the primary endpoint. Methods and Results: We did a prespecified analysis of data from the 21,105 patients with AF enrolled into ENGAGE AF-TIMI 48, a randomized trial comparing two once-daily regimens of edoxaban (high- and low-dose) with warfarin for the prevention of stroke and systemic embolism. Of the 1,016 patients who met the primary endpoint, 67 (6.6%) had a systemic embolic event (SEE) of which 13% were fatal. Risk factors for systemic embolism versus stroke include age (78 versus 74 years; P=0.005), permanent atrial fibrillation (72% versus 54%; P=0.009), and creatinine clearance ≤ 50 mL/min (42% versus 27%; P=0.01). Of the 73 total SEEs (includes multiple events), 62 involved the extremities (85%) and 30 required a surgical or percutaneous intervention (41%). In a meta-analysis of the four major trials comparing novel oral anticoagulants (NOACs) versus warfarin, the NOACs reduce the risk of SEE compared to warfarin (relative risk, 0.63; 95% confidence interval, 0.43 to 0.91; P=0.01), with less bleeding and a better safety profile. Conclusion: Although less frequent than stroke, systemic embolism results in significant morbidity and mortality in patients with AF. In a meta-analysis, NOACs reduce the risk of SEEs compared to warfarin.

New versus Traditional Approaches to Oral Anticoagulation in Patients with Atrial Fibrillation

For clinicians, atrial fibrillation (AFib) is not a disease that will probably be “cured” at some point during their professional lifetime. (online video available at: http://education.amjmed.com/video.php?event_id=445&stage_id=5&vcs=1). AFib is a condition that occurs in association with aging, affecting as many as 1 in 10 patients by the time they reach age 85, and therefore all physicians who read The American Journal of Medicine should be aware of AFib—its etiology, how to recognize it, and with some idea of how it is treated. Perhaps the most important aspect of AFib, however, is as a risk factor for systemic embolism and stroke, which means that almost all patients with AFib will need to receive anticoagulation therapy, probably for the rest of their lives. For the past several decades the only oral anticoagulant agent has been warfarin. Warfarin is an effective anticoagulant, but for many reasons (patient adherence, physician reluctance, warfarin's narrow therapeutic efficacy), less than half of the patients who should be anticoagulated are prescribed warfarin (dropping to less than a third in older patients), and of those who are prescribed and apparently adherent, less than a third maintain serum warfarin levels in the narrow therapeutic range of INR 2-3. Thus, it is clear that the traditional prescription of warfarin for patients with AFib has failed to meet an important need for reducing risk of systemic embolism and stroke. Fortunately, however, within the last couple of years a new generation of novel oral anticoagulant (NOAC) agents has proven successful in randomized clinical trials and has been passing through the regulatory approval process. For physicians this represents both a challenge—to learn and understand the evidence base for these new anticoagulant therapies—and the opportunity now to treat their aging patients who are increasingly likely to present with cerebrovascular disease risks and who are depending on their physicians to treat them with the best evidence-based care available today. To address this need this program reviews: the epidemiology and demographics of AFib; risk reduction for the general patient population with AFib; the new oral anticoagulant agents that may offer alternatives to warfarin; risk reduction for the special patient populations (age, gender, triple-therapy patients).

Vorhofflimmern – epidemiologische, ökonomische und individuelle Krankheitsbelastung

Atrial fibrillation (AF) is the most frequent cardiac arrhythmia. AF affects especially the elderly. The incidence rises with increasing age to over 15% for those over 90 years old. AF is a risk factor for systemic embolism and ischemic stroke. Stroke with AF is more severe with regard to neurologic impairment. In the management of AF an anticoagulation is essential. However, only half of the patients benefit from anticoagulation in therapeutic target ranges. Costs associated with AF accrue to 660 to 924 Mio Euro in Germany with hospitalization being the major cost contributor. Management of stroke patients with AF is at 3000 Euro higher compared to those patients without AF. AF has an impact on patients' wellbeing and impairs patients' quality of life, particularly the symptomatic form. With an increasing ageing of the society it is suggested to ensure that care management for patients with AF will be optimized.

Right atrial appendage thrombus with atrial infarct in a case of thyrotoxicosis: An autopsy report

Cardiac function has long been known to be altered in patients with thyrotoxicosis and atrial fibrillation occurs in patients with hyperthyroidism. In addition to its disabling symptoms, atrial fibrillation is a strong risk factor for systemic embolism, especially with regard to cerebral circulation. A right atrial appendage thrombus formation in atrial fibrillation is a rare phenomenon. In this report, we describe a case of a 30-year-old female, who suffered from hyperthyroidism and subsequently developed atrial fibrillation and a right atrial appendage thrombus with infarction of right atrial appendage.

Managing oral anticoagulant therapy in patients with mechanical heart valves undergoing elective surgery

The optimal perioperative anticoagulation management in patients on warfarin therapy is poorly defined because of the lack of randomized trials. Because guidelines are heterogeneous, we hypothesized that treatment strategies are not uniform in clinical practice. During the Annual Meeting of the Italian Federation of Anticoagulation Clinics, a questionnaire with four different clinical scenarios was distributed. Two scenarios described the cases of patients with a mechanical heart valve in the mitral position and additional risk factors for systemic embolism, one undergoing major surgery (case 1) and one undergoing minor surgery (case 3). Two scenarios described patients with an aortic mechanical heart valve, one undergoing major surgery (case 2) and one minor surgery (case 4). Different preoperative and postoperative management options were offered. Treatment options for all scenarios were the same. Of the 300 questionnaires distributed, 72 were returned (24%). Outpatient full-dose low molecular weight heparin (LMWH) was the most selected strategy in the preoperative phase. It was chosen by 90.3% of participants in case 3, 87.5% in case 1, 62.5% in case 2, and 52.8% in case 4. In the postoperative phase, full-dose LMWH remained the most selected option for cases 1 (75%) and 3 (70.8%), whereas low-dose LMWH was selected by the majority for cases 2 (50%) and 4 (61.1%). Even among expert clinicians, the management of perioperative anticoagulation is heterogeneous. In particular, the definition of risk categories and the optimal intensity of antithrombotic drugs remain to be assessed by well-designed prospective studies.

Hipercoagulabilidad en fibrilación auricular y su relación con factores de riesgo para embolia sistémica

Atrial fibrillation is associated to a high risk of systemic embolism and to hypercoagulability. To evaluate the activation of the coagulation cascade through determinations of the thrombin-antithrombin complex in patients with atrial fibrillation and to correlate this data with the clinical and echocardiographic risk factors for systemic embolism. In 53 patients with atrial fibrillation plasma levels of the thrombin-antithrombin complex were determined on admission to a coronary care unit and 30 days later. Using a univariate and multiple regression analysis, the association basal thrombin-antithrombin with the duration of the arrhythmia, age over 70 years, previous use of antiplatelet agents, history of hypertension, mitral valve disease, diabetes, heart failure, previous systemic embolism, left atrial diameter and the presence of spontaneous contrast echo or thrombus in the left atrial appendage, was studied. Basal thrombin-antithrombin values were 40.1 +/- 69 mg/L (Median 8.34 [3.0-47.5]) compared to 2.7 +/- 3.3 mg/L in healthy controls (p < 0.001). No significant correlation was found between activation of the coagulation cascade and risk factors for systemic embolism. There were no significant differences in thrombin-antithrombin values between patients with chronic or paroxysmal atrial fibrillation (29.5 +/- 43 mg/L and 49.4 +/- 83 mg/L respectively). Mean thrombin-antithrombin values in patients under antiplatelet agents were lower than in those without treatment (17.3 +/- 43 vs 66.8 +/- 127 mg/L; p = 0.018). The activation of the coagulation cascade in patients with atrial fibrillation was confirmed. However, no association of this activation with well known clinical and echocardiographic risk factors for systemic embolism, was found. Previous antiplatelet treatment prevented a higher activation of the coagulation cascade.

A simple scheme to initiate oral anticoagulant treatment in outpatients with nonrheumatic atrial fibrillation

A simple scheme to initiate oral anticoagulant treatment in outpatients with nonrheumatic atrial fibrillation

Disrupted Mobile Aortic Plaques Are a Major Risk Factor for Systemic Embolism in the Elderly

Protruding aortic plaques – especially those with mobile properties – on transesophageal echocardiography (TEE) are a potential source of stroke and systemic embolism in the elderly. Whether the various morphologies of atheromas with mobile components represent potential differences in the risk for embolic events has not been thoroughly elucidated. The goal of the present study was to determine the association between embolic events and the various types of mobile lesions in the thoracic aorta. Our population consisted of 569 consecutive patients (age 18–83 years) referred for TEE over 27 months; 108 (19%) of them were referred to evaluate recent embolism (cerebral in 97 and peripheral or both in 11; group I) and the remaining 461 were admitted for reasons unrelated to embolism (group II). In group I, 35 patients (32%) exhibited protruding plaques; those were fixed in 10 (9%) and with a mobile component in 25 (23%). In group II, plaques were found in only 13 patients (3%); fixed in 9 (2%) and mobile in 4 (1%). Twenty-four patients with mobile lesions in group I were > 50 years old, and 21 of them (88%) were > 60 years old. While the presence of fixed plaques was associated with a moderate increase in the risk for systemic embolism (adjusted odds ratio 4.1; 95% confidence interval 1.3–56.4), mobile lesions were linked to a striking augmentation of this risk (odds ratio 30.1; 95% confidence interval 7.8–132.6). The majority of mobile lesions (76%) in group I represented disrupted atheromas with charateristic ulcerations or echolucency within the plaque suggestive of intraatheroma hemorrhage, whereas these TEE features were not observed in 89% of the mobile lesions in group II (p = 0.0003). We conclude that among the various types of mobile aortic lesions, the disrupted protruding plaques are a major risk factor for stroke and embolic events in the elderly.

Predicting Systemic Embolism in Mitral Stenosis.

Prior retrospective studies have shown that mitral stenosis predisposes patients to systemic embolism, and particularly to cerebral embolism. In this prospective study, Taiwan investigators sought to carefully identify risk factors for systemic embolism. Among …

Evolution of left atrial thrombus with anticoagulant therapy-follow-up by transesophageal echocardiography.

Objectives:Atrial fibrillation is an important risk factor for systemic embolism. A number of clinical studies demonstrated the beneficial effect of anticoagulant therapy for the prevention of embolism. But there has been no study on the fate of left atrial thrombus demonstrated by transesophageal echocardiography in the course of anticoagulation therapy.Methods:Thirteen patients, demonstrated to have left atrial thrombus by transesophageal echocardiography were followed with anticoagulation therapy. Repeated transesophageal echocardiography was done 15 months after 1st study.Results:Among 9 patients with adequate anticoagulation effect (INR>2.0), left atrial thrombus disappeared in 3 patients. The size of thrombus decreased from 2.2±0.8cm to 0.9±1.0cm (p<0.05 by paired Student’s t-test).Conclusions:Left atrial thrombus could dissolve or decrease in size with adequate anticoagulation.

Systemic embolism in aortic arch atheromatosis

The role of aortic atheromatosis as a risk factor for systemic embolism and its relationship to other potential sources of embolism was examined in 335 patients undergoing transoesophageal echocardiography for various clinical reasons. Multiple logistic regression analysis revealed a significant correlation between embolism and moderate (atheroma protruding less than 5 mm into the aortic lumen, grade 2) to complex (atheroma protruding at least 5 mm into the vessel lumen with or without mobile components, grade 3) atherosclerosis of the aortic arch. Odds ratios were 4.0 for grade 2 atheromatosis (95% CI 1.1-14.4; P < 0.05) and 9.7 for grade 3 atheromatosis (95% CI 1.5-61.0; P < 0.05). Other significant associations were found with cardiac thrombi (odds ratio 4.0, 95% CI 1.7-9.3; P < 0.005) and hypertension (odds ratio 1.8, 95% CI 1.0-3.3; P < 0.05). In a subset of 163 patients in whom results of an ultrasound examination were available, atherosclerosis of the carotid arteries was another significant marker of embolism (odds ratio 2.0, 95% CI 1.2-3.3; P < 0.01). In conclusion, aortic arch atheromatosis, which was predominantly recognized in patients with cerebrovascular events of undetermined cause, seems to carry a risk of embolism that is comparable to cardiac and carotid atherosclerosis.

Risk factors for systemic embolism in patients with paroxysmal atrial fibrillation

The purpose of this study was to define the risk factors for systemic embolism in patients with recently diagnosed paroxysmal atrial fibrillation. We therefore studied 63 consecutive patients with symptomatic nonvalvular paroxysmal atrial fibrillation and performed a clinical and noninvasive cardiac, peripheral vascular, and neurologic evaluation that included two-dimensional echocardiography, 24-hour Holter monitoring, and computed tomographic brain scan. Patients with predisposing clinical conditions for systemic embolism (valvular heart or coronary artery disease) or paroxysmal atrial fibrillation (sick sinus disease, preexcitation, or thyroid dysfunction) were excluded. At entry 34 patients had idiopathic paroxysmal atrial fibrillation and 29 had hypertension. Fourteen patients had a recent systemic embolic complication: nine had a recent occlusive nonlacunar cerebrovascular accident, two had transient ischemic attacks, and three had peripheral systemic emboli that required surgery. In addition, five patients had evidence of old cerebrovascular accident on the computed tomographic scan (group 1). Forty-four patients had no systemic embolism (group 2). Results of univariate analysis showed that patients in group 1 were older (72 ± 9 vs 63 ± 13 years, p < 0.05), had a higher incidence of hypertension (70% vs 35%, p < 0.01), and had an increased left atrial diameter (4.1 ± 0.7 vs 3.6 ± 0.5 cm, p < 0.05). Multiple stepwise logistic regression analysis showed that a history of hypertension and left atrial enlargement on two-dimensional echocardiography were significant independent risk factors for systemic embolism in patients with symptomatic nonvalvular paroxysmal atrial fibrillation.