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Background: Although Chagas cardiomyopathy is related to thromboembolic stroke, data on risk factors for cerebrovascular events in Chagas disease is limited. Thus, we assessed the relationship between left ventricular (LV) impairment and cerebrovascular events and sources of thromboembolism in patients with Chagas cardiomyopathy. Methods: This retrospective cohort included patients with chronic Chagas cardiomyopathy who underwent cardiovascular magnetic resonance (CMR). CMR was performed with a 1.5 T scanner to provide LV volumes, mass, ejection fraction (LVEF), and myocardial fibrosis. The primary outcome was a composite of incident ischemic cerebrovascular events (stroke or transient ischemic attack—TIA) and potential thromboembolic sources (atrial fibrillation (AF), atrial flutter, or intracavitary thrombus) during the follow-up. Results: A total of 113 patients were included. Median age was 56 years (IQR: 45–67), and 58 (51%) were women. The median LVEF was 53% (IQR: 41–62). LV aneurysms and LV fibrosis were present in 38 (34%) and 76 (67%) individuals, respectively. The median follow-up time was 6.9 years, with 29 events: 11 cerebrovascular events, 16 had AF or atrial flutter, and two had LV apical thrombosis. In the multivariable model, only lower LVEF remained significantly associated with the outcomes (HR: 0.96, 95% CI: 0.93–0.99). Patients with reduced LVEF lower than 40% had a much higher risk of cerebrovascular events and thromboembolic sources (HR: 3.16 95% CI: 1.38–7.25) than those with normal LVEF. The combined incidence rate of the combined events in chronic Chagas cardiomyopathy patients with reduced LVEF was 13.9 new cases per 100 persons-year. Conclusions: LV systolic dysfunction is an independent predictor of adverse cerebrovascular events and potential sources of thromboembolism in patients with chronic Chagas cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background: Transesophageal echocardiography (TEE) is variably performed before atrial fibrillation (AF) ablation to evaluate left atrial appendage (LAA) thrombus. We describe our experience with transitioning to the pre‐ablation cardiac computed tomography (CT) approach for the assessment of LAA thrombus during the COVID‐19 pandemic. Methods: We studied consecutive patients undergoing AF ablation at our center. The study cohort was divided into pre‐ versus post‐COVID groups. The pre‐COVID cohort included ablations performed during the 1 year before the COVID‐19 pandemic; pre‐ablation TEE was used routinely to evaluate LAA thrombus in high‐risk patients. Post‐COVID cohort included ablations performed during the 1 year after the COVID‐19 pandemic; pre‐ablation CT was performed in all patients, with TEE performed only in patients with LAA thrombus by CT imaging. The demographics, clinical history, imaging, and ablation characteristics, and peri‐procedural cerebrovascular events (CVEs) were recorded. Results: A total of 637 patients (pre‐COVID n = 424, post‐COVID n = 213) were studied. The mean age was 65.6 ± 10.1 years in the total cohort, and the majority were men. There was a significant increase in pre‐ablation CT imaging from pre‐ to post‐COVID cohort (74.8% vs. 93.9%, p ≤.01), with a significant reduction in TEEs (34.6% vs. 3.7%, p ≤.01). One patient in the post‐COVID cohort developed CVE following negative pre‐ablation CT. However, the incidence of peri‐procedural CVE between both cohorts remained statistically unchanged (0% vs. 0.4%, p =.33). Conclusion: Implementation of pre‐ablation CT‐only imaging strategy with selective use of TEE for LAA thrombus evaluation is not associated with increased CVE risk during the COVID‐19 pandemic. [ABSTRACT FROM AUTHOR]

Recent evidence indicates that our understanding of the relationship between cardiac function and ischemic stroke remains incomplete. The Cardiovascular Health Study enrolled community-dwelling adults ≥ 65 years old. We included participants with speckle-tracking data from digitized baseline study echocardiograms. Exposures were left atrial reservoir strain (primary), left ventricular longitudinal strain, left ventricular early diastolic strain rate, septal e' velocity, and lateral e' velocity. The primary outcome was incident ischemic stroke. Cox proportional hazards models were adjusted for demographics, image quality, and risk factors including left ventricular ejection fraction and incident atrial fibrillation. Among 4,000 participants in our analysis, lower (worse) left atrial reservoir strain was associated with incident ischemic stroke (HR per SD absolute decrease, 1.14; 95% CI 1.04–25). All secondary exposure variables were significantly associated with the outcome. Left atrial reservoir strain was associated with cardioembolic stroke (HR per SD absolute decrease, 1.42; 95% CI 1.21–1.67) and cardioembolic stroke related to incident atrial fibrillation (HR per SD absolute decrease, 1.60; 1.32–1.95). Myocardial dysfunction that can ultimately lead to stroke may be identifiable at an early stage. This highlights opportunities to identify cerebrovascular risk earlier and improve stroke prevention via therapies for early myocardial dysfunction. [ABSTRACT FROM AUTHOR]

Purpose: Stroke risk factors are divided into modifiable and non-modifiable. As much as 90% of stroke incidence is provoked by modifiable risk factors. The aim of the study was to assess the pre-stroke risk factors' detection in the population of Szczecin during a decade. Methods: Retrospective analysis of consecutive ischemic stroke patients, including transient ischemic attack (TIA), hospitalised between 2003 and 2005 (group I, n = 1524) as compared to the period from 2013 to 2014 (group II, n = 869). Results: The mean age of population in group I was 70 years as compared to 74 in group II (p < 0.001). The pre-hospital detection of the main ischemic stroke risk factors increased significantly, which refers mainly to hypertension, coronary heart disease, atrial fibrillation, diabetes and dyslipidemia; however, acute coronary syndrome remained at the same level. The frequency of in-hospital detection decreased in diabetes and dyslipidemia with no change of hypertension and coronary heart disease. Atrial fibrillation was the only analysed risk factor that was more frequently detected both pre- and in-hospital after 10 years. The frequency of excessive drinking and smoking decreased throughout the decade. There were no changes in neurological deficit and mortality during the hospitalisation. TIA was more often observed in group II. Conclusions: During a decade, we observed an improvement in detection of the main modifiable stroke risk factors, including reduction in the habits frequency that lead to increase in the age at stroke onset. The detection and management within the risk factors in the primary prevention of stroke in the group of Polish stroke patients improved in the analysed period. [ABSTRACT FROM AUTHOR]

Numerous vascular risk factors and vascular diseases contribute to cognitive impairment and dementia. Many studies and registries show an association of atrial fibrillation (AF) with cognitive impairment, cognitive decline, and dementia. This is true for vascular dementia and Alzheimer's disease. The assumed multifactorial mechanisms include ischemic stroke, both apparent and silent, cerebral microinfarcts, cerebral hemorrhage, and reduced cerebral blood flow. A number of retrospective observational and prospective studies support that anticoagulation in patients with AF may reduce the risk of cognitive decline and dementia. This holds for both vitamin K antagonists (e.g., warfarin) and direct oral anticoagulants. However, it still remains unproven if anticoagulation reduces cognitive decline and dementia in AF patients based on randomized trials. [ABSTRACT FROM AUTHOR]

Background: South Asians have a lower prevalence of atrial fibrillation (AF) compared with Caucasians despite higher rates of conventional risk factors and a higher incidence of stroke. It is not clear whether South Asians truly experience less AF or whether this is due to underdetection of the arrhythmia. Therefore, we aimed to determine whether South Asian patients with pacemakers have a lower incidence of device‐detected subclinical episodes of AF compared with Caucasian controls. Methods: We performed a retrospective cohort study of South Asian and Caucasian patients who underwent pacemaker implantation between 2006 and 2016. Subclinical AF episodes, detected during subsequent device clinic follow‐up visits, were identified and the occurrence of clinical AF, cerebrovascular events, and all‐cause mortality was recorded. Results: A total of 5 648 patients underwent pacemaker implantation at the Yorkshire Heart Centre, UK, during the study period. Of these, 169 were South Asian and 72 met the eligibility criteria. The cumulative incidence of subclinical AF was significantly lower in South Asians compared with Caucasians (logrank P  =  0.002) with an annual event rate of 6.9% versus 13.9%, and South Asian ethnicity was an independent predictor of a lower incidence of subclinical AF (odds ratio =  0.43; 95% confidence interval  =  1.01‐5.38). Conclusions: South Asians with an implanted pacemaker have a lower rate of subclinical AF compared with Caucasians. [ABSTRACT FROM AUTHOR]

OBJECTIVES Postoperative atrial fibrillation (POAF) is a common complication after coronary artery bypass grafting. Although transient, POAF is linked to increased late mortality. We hypothesized that POAF increases late cerebrovascular (CeV) and composite cerebrovascular/cardiovascular/vascular (CV* = CeV + CV + Other-V) but not non-cardiovascular (Non-CV) mortality. METHODS We analysed 8807 non-salvage coronary artery bypass grafting patients (1994–2011). Fifteen-year and time-segmented (early, 0–1 year; intermediate, 1–6 years and late, 6–15 years) all-cause and cause-specific mortality were compared for POAF versus No-POAF patients. Corresponding POAF versus No-POAF adjusted hazard ratios [AHRs (95% confidence interval, CI)] were derived using the competing risk Cox regression. RESULTS POAF occurred in 1992 (23%) patients. Complications other than POAF occurred in 1875 (21%) patients but were more frequent among POAF patients (31% vs 18%; P  < 0.001). Overall mean follow-up was 9 ± 4 years. POAF patients had a higher 15-year unadjusted mortality (53% vs 39%; P  < 0.001) and were consequently associated with higher adjusted all-cause [AHR (95% CI) = 1.23 (1.14–1.33)] and composite cardiovascular [CV*: AHR (95% CI) = 1.15 (1.02–1.30)] mortality. The trends towards a higher 15-year CeV [AHR (95% CI) = 1.34 (0.94–1.91)] and Non-CV [AHR (95% CI) = 1.12 (0.99–1.26)] mortality were not significant. Time-segmented analyses showed that (i) POAF increased all-cause mortality early, and this persisted in the intermediate and late periods and (ii) CeV [AHR (95% CI) = 2.14 (1.14–4.04)] and CV* [AHR (95% CI) = 1.31 (1.06–1.62)] mortality rates were increased in the intermediate but not in the early or late periods. Non-CV mortality was similar in POAF and No-POAF for all time intervals. These findings were corroborated in propensity-matched sub-cohorts and in sensitivity analyses in patients free of any other complication. CONCLUSIONS POAF is associated with worse long-term survival principally driven by increased intermediate-term cerebrovascular and cardiovascular mortality, while Non-CV mortality was similar. [ABSTRACT FROM AUTHOR]

Background: Patients who develop herpes zoster or herpes zoster ophthalmicus may be at risk for cerebrovascular and cardiac complications. We systematically reviewed the published literature to determine the association between herpes zoster and its subtypes with the occurrence of cerebrovascular and cardiac events. Methods/Results: Systematic searches of PubMed (MEDLINE), SCOPUS (Embase) and Google Scholar were performed in December 2016. Eligible studies were cohort, case-control, and self-controlled case-series examining the association between herpes zoster or subtypes of herpes zoster with the occurrence of cerebrovascular and cardiac events including stroke, transient ischemic attack, coronary heart disease, and myocardial infarction. Data on the occurrence of the examined events were abstracted. Odds ratios and their accompanying confidence intervals were estimated using random and fixed effects models with statistical heterogeneity estimated with the I2 statistic. Twelve studies examining 7.9 million patients up to 28 years after the onset of herpes zoster met our pre-defined eligibility criteria. Random and fixed effects meta-analyses showed that herpes zoster, type unspecified, and herpes zoster ophthalmicus were associated with a significantly increased risk of cerebrovascular events, without any evidence of statistical heterogeneity. Our meta-analysis also found a significantly increased risk of cardiac events associated with herpes zoster, type unspecified. Conclusions: Our results are consistent with the accumulating body of evidence that herpes zoster and herpes zoster ophthalmicus are significantly associated with cerebrovascular and cardiovascular events. [ABSTRACT FROM AUTHOR]

Background Whether patients with atrial fibrillation (AF) and liver disease are also prone to cerebrovascular events and respond similarly favorably to antithrombotic therapy remains under-investigated. Methods Patients ≥ 18 years with newly-diagnosed AF in the period 2005 to 2009 were scrutinized from the “Longitudinal Health Insurance Database 2005” (1 million beneficiaries) of Taiwan's National Health Insurance Institute. Patients were categorized into the Liver ( N = 433) or the Non-liver ( N = 3490) cohort according to whether they had a diagnosis of advanced liver disease. Patients were then followed to determine cumulative incidence of hospitalization-requiring cerebrovascular events, preventive effects of antithrombotics, and predictors of cerebrovascular events by Cox regression analysis. Results Within a mean follow-up of 3.3 ± 1.4 years, ischemic stroke (89.2 vs. 50.3 per 1000 person-years, adjusted HR 1.502, 95% CI 1.207–1.868, p < 0.001) and overall cerebrovascular events (102.3 vs. 56.4 per 1000 person-years, adjusted HR 1.535, 95% CI 1.251–1.883, p < 0.001) occurred significantly more often in the Liver than in the Non-liver cohort. Cox models identified aging (≥ 65 years), DM, and CHA2DS-VASc score ≥ 2 points as risk factors for overall cerebrovascular events in the Liver cohort, whereas antiplatelet agents (HR 0.932, 95% CI 0.128–6.803, p = NS) and vit-K antagonistic anticoagulants (HR 1.087, 95% CI 0.150–7.862, p = NS) showed no correlation. Conclusion AF patients comorbid with advanced liver disease are more vulnerable to ischemic and therein overall cerebrovascular events, especially in those with old age, DM, or high CHA2DS-VASc scores. This propensity to cerebrovascular events, however, can't be altered by antithrombotic therapy. [ABSTRACT FROM AUTHOR]

Background: To investigate prevalence and risk factors for post stroke pneumonia (PSP) in patients with acute ischemic stroke treated at stroke units (SU).Method: We analysed data from the Austrian Stroke Unit registry concerning admissions from January 2003 to December 2013 and assessed the prevalence of PSP at the stroke unit. Patients with and without PSP were compared in univariate and multivariate models searching for factors associated with the occurrence of PSP at the SU.Results: Three thousand one hundred eleven patients (5.2%) of 59,558 analysed patients were diagnosed with PSP. While age and stroke severity were non-modifiable factors associated with PSP, modifiable risk factors included chronic alcohol consumption and atrial fibrillation. Patients who developed neurological, cardiac, and other infective complications showed a higher prevalence of PSP, an increased prevalence was also found in connection with the placement of nasogastric tubes or urinary catheters. Female sex, left hemispheric stroke, cryptogenic stroke pathogenesis and additionally, treatment with lipid lowering drugs were factors associated with a lower PSP prevalence.Conclusion: Pneumonia in acute ischemic stroke is associated with a variety of modifiable and unmodifiable factors that allow to identify patients at high risk of developing PSP and to focus on early preventive measures at the SU. Further studies could use the results of this study to explore potential benefits of specific interventions targeted at these factors. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the in-hospital stroke and in-hospital mortality risks associated with new-onset atrial fibrillation (AF) in patients with severe sepsis. Adults hospitalized in California's nonfederal acute care hospitals in 2007 served as subjects in this study. To explore the temporality of severe sepsis, AF and ischemic stroke events, both sensitivity and exploratory analyses were performed. Results of the study showed that 40,082 patients were hospitalized due to severe sepsis. The ethnic composition of hospitalized patients are white, Hispanic, and African Americans. It cites demographics and comorbidities as factors associated with increased risk of new-onset AF. It notes that 3,310 adult hospitalizations were associated with in-hospital stroke.

The article offers updates on atrial fibrillation (AF) management. It reviews the classification of AF, the epidemiology, etiology, symptoms and manifestations and the strategic objectives in AF management involving rhythm control, rate control and thromboembolism prevention that can be achieved through non-pharmacological and pharmacological means. It also notes oral anticoagulant therapy, antiarrhythmic drugs, pacemaker therapy and implantable atrial defibrillators.

Stroke prophylaxis in patients with non-valvular atrial fibrillation is becoming an increasingly dynamic field. The new guidelines from the European Society of Cardiology (ESC) recommend a stroke- and bleeding risk-assessment in patients with non-valvular atrial fibrillation using the CHA2DS2VASc and the HAS-BLED scores, respectively. Furthermore, new drugs for stroke prophylaxis such as dabigatran, rivaroxaban and apixaban are undergoing approval in Europe and will undoubtedly challenge the well-established vitamin K antagonists. Hence, stroke prophylaxis is likely to become a much more individualized treatment in the future. This review should help to critically weigh the pros and the cons of the new therapeutic options. [ABSTRACT FROM AUTHOR]

Abstract: Background: The CHADS2 score is a stroke risk stratification system for patients with atrial fibrillation (AF). The relationship between the pre-admission CHADS2 score and stroke severity or outcome was examined in AF-related cardioembolic stroke patients. Methods: 423 consecutive AF-related cardioembolic stroke patients (250 men, 173 women; aged 76±10years) were reviewed. Results: Pre-admission CHADS2 scores of 0, 1, 2, 3, 4, 5, and 6 were present in 4.3%, 21.0%, 34.3%, 23.6%, 11.8%, 4.5%, and 0.5% of patients, respectively. There were significant correlations (P<0.001) between CHADS2 and National Institutes of Health Stroke Scale (NIHSS) scores on admission, and CHADS2 and modified Rankin scale (mRS) scores at discharge. The optimal cutoff CHADS2 score for an mRS score ≥3 was ≥2 (sensitivity 84%, specificity 38%). For death, the optimal cutoff CHADS2 score was ≥3 (sensitivity 59%, specificity 62%). On multivariate analysis, a CHADS2 score ≥2 was independently associated with an mRS score ≥3 (OR 1.93, 95% CI 1.39–2.72, P<0.001), and a CHADS2 score ≥3 was independently associated with death (OR 1.46, 95% CI 1.02–2.11, P=0.038). Conclusions: The CHADS2 score is related to severity and outcomes of stroke in patients with AF. [Copyright &y& Elsevier]

Background and Objective: Brachial arterial flow-mediated dilation (FMD) is associated with an increased risk of vascular events. Our aim was to investigate the relationship between FMD measured in the acute phase of ischemic stroke and a new major adverse vascular event in a consecutive cohort of patients followed up for 48 months after an acute first-ever stroke. Methods: We measured FMD in 120 consecutive patients with acute ischemic stroke using high-resolution ultrasonography. FMD was calculated as the relationship between the basal diameter of the brachial artery before and after transient vascular occlusion. Intima-media thickness, extracranial carotid atherosclerosis, stroke severity National Institute of Health Stroke Scale, and modified Rankin Scale at 3 months were also evaluated. A vascular event was defined as any of the following: vascular disease (VD) death, nonfatal myocardial infarction (MI), nonfatal recurrent stroke (RS), claudication or peripheral arterial thrombosis (PVD), angioplasty or cardiac bypass graft surgery. Results: There were 34 new major adverse vascular events in 32 of 120 patients (26.7%): 21 (61.8%) RS, 5 (14.7%) VD death, 5 (14.7%) MI, and 3 (8.8%) PVD. The presence of carotid artery plaque (81.3 vs. 46%; p < 0.0001), atrial fibrillation (37.5 vs. 14.8%; p = 0.007) and FMD (5.30 ± 7.48 vs. 10.54 ± 7.02; p = 0.001) were associated with new-onset vascular events. FMD ≤4.5% was an independent predictor of new-onset vascular events (hazards ratio 3.48; 95% confidence interval 1.26-9.63; p = 0.01). Conclusions: FMD is an independent predictor for a new-onset vascular event after first-ever ischemic stroke. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Background: : Atrial fibrillation (AF) is a risk factor for ischemic stroke. Stroke-prevention strategies based on risk schemes have been developed but most of the data are from western people. Our goal is to investigate the risk factors of ischemic stroke in Taiwanese with AF in a nation-wide database. Methods: : A universal national health insurance (NHI) program has been implemented in Taiwan since 1995. We used system sampling database from 1997 to 2008 with a total of 1,000,000 subjects. By using ambulatory and inpatient claim data, we included subjects with AF and were above 20 years old. We excluded those who had ever taken warfarin or aspirin or had valvular heart diseases. Result: : A total of 7920 patients (3633 women, 4287 men) were included in the final analyses. Cox regression analysis showed that the risk factors for ischemic stroke were age (OR=1.338 for age 65–74 years vs. age 20–64 years, P =0.014; OR=1.652 for age over 75 years vs. age 20–64years, P <0.001), hypertension (HTN) (OR=2.656, P <0.001), diabetes mellitus (DM) (OR=1.341, P =0.005), heart failure (OR=1.611, P <0.001), previous ischemic stroke or transient ischemic accident (TIA) (OR=2.752, P <0.001) and peripheral arterial disease (PAD) (OR=1.814, P =0.006). The gender, coronary artery disease, history of myocardial infarction and chronic renal insufficiency were not associated with ischemic stroke. The rate of ischemic stroke was much lower in current cohort as compared with that in whites. Frequent used risk schemes including CHADS2 and CHA2DS2-VASC had comparable but only limited ability to predict ischemic stroke in subjects with AF. Conclusion: : Compare with western people, hypertension plays a more important role in ischemic stroke in Taiwanese with AF and the incidence is lower. A substantial number of ischemic strokes cannot be accurately predicted by current risk schemes. [Copyright &y& Elsevier]

The article discusses various cardiovascular medical conditions that are associated with sleep apnoea syndromes. The syndromes are categorized into three main disorders namely central sleep apnoea (CSA), Cheyne-Stokes respiration (CSR) and obstructive sleep apnoea. It says that these are also linked to enhanced coronary artery calcification as well as prevalence of myocardial infarctions.

The article presents a study which assessed the adequacy of congestive heart failure, hypertension, age ≥ 75 years old, diabetes, stroke [doubled] (CHADS2) for thromboembolism (TE) risk stratification while evaluating cardiac risk in patients with atrial fibrillation (AF) revascularized with coronary artery stents. It assesses the benefits and risk of oral anticoagulation (OAC) therapy. It cites the U.S. National Study for Prevention of Embolism in Atrial Fibrillation (NASPEAF) trial.

The article presents basic and new information about treatment and management of atrial fibrillation (AF). AF is defined as the most common and sustained heart rhythm disorder associated with old age. An explanation of how AF occurs, its causes and manifestions are given in detail. The European Heart Rhythm Association developed a classification tool guide that clinicians can use to decide what course of management to apply. Discussion of rate control, rhythm control, therapies like catheter ablation, and medicines like dronedarone are also mentioned.

Objectives: This study tried to determine the association between left atrial (LA) fibrosis, detected using delayed-enhanced magnetic resonance imaging (DE-MRI), and the CHADS2 score (point system based on individual clinical risk factors including congestive heart failure, hypertension, age, diabetes, and prior stroke) variables, specifically stroke. Background: In patients with atrial fibrillation (AF), conventional markers for the risk of stroke base their higher predictive effect on clinical features, particularly previous stroke history, and not individual LA pathophysiological properties. We aimed to determine the association between LA fibrosis, detected using DE-MRI, and the CHADS2 score variables, specifically stroke. Methods: Patients with AF who presented to the AF clinic and received a DE-MRI of the LA were evaluated. Their risk factor profiles, including a CHADS2 score, were catalogued. The degree of LA fibrosis was determined as a percentage of the LA area. Any history of previous strokes, warfarin use, or cerebrovascular disease was recorded. Results: A total of 387 patients, having a mean age of 65 ± 12 years, 36.8% female, were included in this study. A history of previous stroke was present in 36 (9.3%) patients. Those patients with previous strokes had a significantly higher percentage of LA fibrosis (24.4 ± 12.4% vs. 16.2 ± 9.9%, p < 0.01). A larger amount of LA fibrosis was also seen in those patients with a higher CHADS2 score (≥2: 18.7 ± 11.4 vs. <2: 14.7 ± 9.2, p < 0.01). A logistic regression analysis of all variables except strokes (CHAD score) demonstrated that LA fibrosis independently predicted cerebrovascular events (p = 0.002) and significantly increased the predictive performance of the score (area under the curve = 0.77). Conclusions: Our preliminary, multicenter results suggest DE-MRI–based detection of LA fibrosis is independently associated with prior history of strokes. We propose that the amount of DE-MRI–determined LA fibrosis could represent a marker for stroke and a possible therapeutic target with potential applicability for clinical treatment for patients with AF. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

The prevalence of atrial fibrillation (AF) is related to age and is projected to rise exponentially as the population ages and the prevalence of cardiovascular risk factors increases. The risk of ischemic stroke is significantly increased in AF patients, and there is evidence of a graded increased risk of stroke associated with advancing age. Oral anticoagulation (OAC) is far more effective than antiplatelet agents at reducing stroke risk in patients with AF. Therefore, increasing numbers of elderly patients are candidates for, and could benefit from, the use of anticoagulants. However, elderly people with AF are less likely to receive OAC therapy. This is mainly due to concerns about a higher risk of OAC-associated hemorrhage in the elderly population. Until recently, older patients were under-represented in randomized controlled trials of OAC versus placebo or antiplatelet therapy, and therefore the evidence base for the value of OAC in the elderly population was not known. However, analyses of the available trial data indicate that the expected net clinical benefit of warfarin therapy is highest among patients with the highest untreated risk for stroke, which includes the oldest age category. An important caveat with warfarin treatment is maintenance of a therapeutic international normalized ratio, regardless of the age of the patient, where time in therapeutic range should be ≥65%. Therefore, age alone should not prevent prescription of OAC in elderly patients, given an appropriate stroke and bleeding risk stratification. [ABSTRACT FROM AUTHOR]

Abstract: Risk factors for stroke and thromboembolism in patients with atrial fibrillation used in current risk stratification schema are derived largely from analyses of clinical trial cohorts, and the available data depend on the comprehensiveness of trial reports and whether specific risk factors were sought. The most commonly used schema is the Cardiac failure, Hypertension, Age, Diabetes, Stroke [Doubled] (CHADS2) score. Although simple and well validated, some limitations of CHADS2 this schema are apparent. A more recent approach to risk stratification of patients with nonvalvular atrial fibrillation defines “major (definitive)” risk factors (eg, previous stroke/transient ischemic attack and age≥75 years) and “clinically relevant non-major” risk factors (eg, heart failure, hypertension, diabetes, female gender, age 65-75 years, and atherosclerotic vascular disease). This scheme can be expressed as an acronym, CHA2DS2-VASc, denoting Cardiac failure or dysfunction, Hypertension, Age≥75 [Doubled], Diabetes, Stroke [Doubled]–Vascular disease, Age 65-74, and Sex category [Female]), whereby 2 points are assigned for a history of stroke or age 75 years or more and 1 point each is assigned for age 65 to 74 years, a history of hypertension, diabetes, cardiac failure, and vascular disease. Patients with 1 definitive risk factor or a patient with a CHA2DS2-VASc score of 1 or more could be considered for oral anticoagulation, but a patient with a CHA2DS2-VASc score of 0 is truly low risk and could be managed with no antithrombotic therapy. This would simplify our approach to thromboprophylaxis in patients with atrial fibrillation. [Copyright &y& Elsevier]

Background: Multiple factors influence warfarin metabolism and can significantly affect the risk of adverse events. The extent to which patients understand the modifiable factors that impact on warfarin safety and efficacy is unclear. Methods: A 52-item questionnaire related to knowledge of warfarin was administered to patients with atrial fibrillation in a face-to-face interview with a dietitian. Results were compiled based on five categories: general warfarin knowledge, compliance, drug interactions, herbal or vitamin interactions, and diet. Results: 100 patients were surveyed. Stroke risk factors included hypertension (57%), heart failure (36%), age >75 years (33%), diabetes (22%), and prior stroke/transient ischemic attack (29%). The majority were either high-school (49%) or college graduates (27%). Ten (10%) had a stroke while on warfarin, 11 (11%) had a blood transfusion, and 26 (26%) had at least one fall. The percentages correct for questionnaire items in the five categories were as follows: general knowledge (62%), compliance (71%), drug interactions (17%), herbal or vitamin interactions (7%), and diet (23%). Neither education level nor duration of therapy correlated with warfarin knowledge. Patients at highest risk of stroke had very low knowledge scores in general. Discussion: Patients on warfarin have a poor general understanding of the medication, particularly those at highest risk of stroke. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Transient ischemic attack (TIA) has been described as a brief episode of focal neurologicaldys function caused by acute brain or retinal ischemia, without evidence of acute infarction. According to classical definition, acute focal symptoms of TIA resolve completely within 24 hours after the onset, however, their common duration is less than 1 hour. 33% of patients with transient neurological episode lasting up to 1 hour already have new ischemic lesions on diffusion weighted MRI scan, suggesting that 1 hour also does not demarcate events with and without brain tissue infarction. Therefore current guidelines endorse the following revised definition without any particular time-point: TIA - a transient episode of neurologicaldys function caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. Transient ischemic attack has long been known as a precursor to ischaemic stroke. Up to 50% strokes after TIA occur within the first 2 days. The simple and reliable ABCD2 score was derived to provide a prediction of early stroke risk after TIA. Patients with TIA score risk points (indicated in parentheses) for each of the 5 following factors: age ≥60 years (1); blood pressure ≥140/90 mm Hg (1); clinical symptoms of focal weakness (2) or speech impairment without weakness (1); duration ≥60 minutes (2) or 10 to 59 minutes (1); diabetes (1). According to ABCD2 total scores stroke risk could be stratified as low (0-3), moderate (4-5) or high (6-7). Other suggested criteria of high risk of stroke after TIA are symptomatic carotid stenosis >50% and atrial fibrillation. Therefore ABCD2 score may be supplemented with carotid ultra sound evaluation and ECG. Recent SOSTIA and EXPRESS clinical trials evaluated the efficacy of early assessment and immediate implementation of preventive measures for patients after TIA. Results of urgent TIA management revealed up to 80% relative risk reduction of stroke within the following 90 days. [ABSTRACT FROM AUTHOR]

Abstract: Background: Clinical guidelines for the management of atrial fibrillation and atrial flutter provide recommendations for anticoagulation based on patients'' overall risk of stroke. To determine the real-world compliance of physicians with these recommendations, we conducted a retrospective cohort study examining the utilization of warfarin in atrial fibrillation/flutter patients by stroke risk level. Methods: Patients with a qualifying atrial fibrillation/flutter diagnosis during ≥18 months'' continuous enrollment between January 2003 and September 2007, and with ≥6 months'' eligibility after the first atrial fibrillation/flutter diagnosis, were identified from the US MarketScan database (Thomson Reuters, New York, NY). Warfarin use within 30 days of the first diagnosis was assessed according to stroke risk, estimated using the Congestive heart failure, Hypertension, Age >75 years, Diabetes, Stroke (CHADS2) score. Results: Of 171,393 patients included in the analysis, 20.0% had a CHADS2 score of 0 (low risk), 61.6% a score of 1-2 (moderate risk), and 18.4% a score of 3-6 (high risk). Warfarin, recommended for high stroke-risk patients, was given to only 42.1% of those with a CHADS2 score of 3-6. A similar percentage of patients with moderate (43.5%) or low stroke risk (40.1%) received warfarin. Only 29.6% of high-risk, 33.3% of moderate-risk, and 34.1% of low-risk patients who were started on warfarin received uninterrupted therapy for 6 months following their initial prescription. Conclusions: These data suggest that guideline recommendations that anticoagulation should be provided in accordance with stroke risk in atrial fibrillation patients are not routinely followed in clinical practice. The causes and clinical implications of under-utilization of anticoagulation in atrial fibrillation patients with high stroke risk warrant further study. [Copyright &y& Elsevier]

Abstract: Background: We investigated atrial fibrillation (AF) prevalence, incidence and the risk of stroke and all-cause death because little is known about AF risk among ethnic Chinese. Methods: We conducted a community-based prospective cohort study among 3560 participants. Prevalent and incident AF was documented by using the 12-lead ECG in baseline and serial follow-ups, and the stroke and all-cause death events were ascertained. Results: Overall prevalence rates of AF in the cohort were 1.4% in men and 0.7% in women. Incidence rates of AF were 1.68 per 1000 person-years for men and 0.76 per 1000 person-years for women. During a median 13.8 years'' follow-up, we documented 208 cases of stroke and 776 deaths. As compared with those without AF, participants with AF had nearly 4 times the age, gender-adjusted risk of stroke (relative risk [RR], 3.87, 95% confidence interval [CI], 2.12–7.15), and twice the risk of death associated with all causes (RR, 2.23, 95% CI, 1.52–3.27). Further adjustment for body mass index, lifestyle factors, socioeconomic status and clinical diseases slightly attenuated these risks. In addition, after adjusting for echocardiographic measures, the following risks remained significant: the multivariate RRs were 2.90 (95% CI, 1.28–6.59) for risk of stroke and 2.05 (95% CI, 1.27–3.32) for risk of all-cause death among participants with AF. Conclusion: Our data demonstrate that AF is a significant risk factor for stroke and all-cause death for the Chinese. [Copyright &y& Elsevier]

Thromboembolism is a severe complication in atrial fibrillation. This overview presents thromboembolic disease as a single entity, ranging from stroke through mesenteric ischemia to acute limb ischemia. The PubMed, Embase, and Cochrane databases were systematically searched for the terms “atrial fibrillation” and “thromboembolism” in reports published from January 1986 to September 2009. The information of 10 evidence-based practice guideline documents and 61 further sources was systematically extracted. In atrial fibrillation, the average annual stroke risk is increased by 2.3% (lethality 30%). The annual incidence of acute mesenteric ischemia is 0.14% (lethality 70%), and that of acute limb ischemia is 0.4% (lethality 16%). In total, approximately 80% of embolism-related deaths are from stroke and 20% from other systemic thromboembolism. The ischemic symptoms generally have an acute onset but may mimic other diseases, particularly in mesenteric ischemia. Early diagnosis and treatment can limit or even prevent tissue infarction. Guideline-recommended therapy with aspirin or warfarin reduces the thromboembolic risk. Suitable patients may optimize their warfarin therapy by self-monitoring of the international normalized ratio (INR). New oral and parenteral anticoagulants with more stable pharmacokinetics are being developed. In conclusion, atrial fibrillation predisposes to thromboembolism. If ischemic stroke or systemic thromboembolism occurs, early diagnosis and treatment can improve outcomes. The thromboembolic risks are reduced by guideline-adherent antithrombotic therapy with warfarin or aspirin. Future directions may include self-monitoring of the international normalized ratio and novel anticoagulants. [Copyright &y& Elsevier]

Atrial fibrillation (AF) is a common complication of acute myocardial infarction (AMI) and this arrhythmia is associated with increased morbidity and mortality in patients with AMI. Limited information is available, however, about changing, and contemporary, trends in the incidence and death rates associated with AF complicating AMI. We examined the magnitude and impact of AF and the risk of stroke and hospital and long-term death rates in a population-based study of patients hospitalized with AMI. The study population consisted of 7,513 residents of the Worcester, Massachusetts, metropolitan area hospitalized with AMI at all greater Worcester medical centers during 9 biennial years from 1990 to 2005. Overall incidence of AF complicating AMI was 13.3% and rates of AF increased during the most recent years under study. Patients who developed AF were at greater risk for acute stroke (adjusted odds ratio 2.25, 95% confidence interval 1.36 to 3.71) and dying during hospitalization (adjusted odds ratio 1.79, 95% confidence interval 1.46 to 2.19) compared with patients who did not develop AF during hospitalization for AMI. Postdischarge survival was significantly poorer in patients who developed AF. Odds of dying after AF did not change appreciably over the years under study. In conclusion, results of this study in residents of a large New England metropolitan area suggest that AF remains a frequent complication of AMI and is associated with a poor prognosis. Increased surveillance and targeted therapeutic approaches appear warranted for these high-risk patients. [Copyright &y& Elsevier]

Atrial fibrillation (AF) is the most common cardiac arrhythmia encountered in clinical practice. The abnormal rhythm is associated not only with a variety of symptoms, such as palpitations, dizziness, or shortness of breath, but also with increased risk of stroke, heart failure, and mortality. A genetic predisposition is suggested by the fact that the relative risk for the development of AF is estimated at 85% in individuals with at least one parent with a history of AF. Current therapeutic strategies include control of rate or rhythm with medication and catheter ablation procedures. Especially in the pathophysiology of paroxysmal AF, ectopic electrical activity originating in the myocardial sleeves surrounding the pulmonary veins is considered causal. In these cases, ablation is applied to isolate the pulmonary venous myocardium from the remainder of the left atrial myocardium. Other recent evidence has shown that genetic and developmental defects can be involved in the development of AF. In this review, it is our aim to discuss the possible underlying causes of AF from a combined genetic and cardiac developmental view. [Copyright &y& Elsevier]

Background: Genetic variants of the warfarin sensitivity gene CYP2C9 have been associated with increased bleeding risk during warfarin initiation. Studies also suggest that such patients remain at risk throughout treatment.Objective: Would testing patients with non-valvular atrial fibrillation (AF) for CYP2C9 before initiating warfarin improve outcomes?Design: Markov state transition decision model.Setting: Ambulatory or inpatient settings necessitating new initiation of anticoagulation.Patients: The base case was a 69-year-old man with newly diagnosed non-valvular AF. Interventions included: (1) warfarin, (2) aspirin, or (3) no antithrombotic therapy without genetic testing; and genetic testing followed by (4) aspirin or (5) no antithrombotic therapy in those with culprit CYP2C9 alleles.Measures: Quality-adjusted life years (QALYs).Results: In the base case, testing and treating patients with CYP2C9*2 and/or CYP2C9*3 with aspirin rather than warfarin was best (8.97 QALYs). However, warfarin without genetic testing was a close second (8.96 QALYs), a difference of roughly 5 days. Sensitivity analyses demonstrated that genetic testing followed by aspirin was best for patients at lower risk of embolic events. Warfarin without testing was preferred if the rate of embolic events was greater than 5% per year, or the risk of major bleeding while receiving warfarin was lower.Conclusion: For patients at average risk for ischemic stroke due to AF and at average risk for major hemorrhage, treatment based on genetic testing offers no benefit compared to warfarin initiation without testing. The gain from testing may be larger in patients at lower risk of embolic events or at greater risk of bleeding. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: We aimed to determine the level of INR control associated with reduced stroke and mortality. Material and methods: The study used a retrospective cohort design using linked inpatient, haematology and mortality data from Cardiff and the Vale of Glamorgan, UK. Anonymised patients admitted with a diagnosis of non-valvular atrial fibrillation (NVAF) were defined as warfarin or non-warfarin treated by number of repeated International Normalised Ratio (INR) tests. Warfarin treated patients (>5 INR tests) categorised as at moderate or high risk of stroke (CHADS2 score ≥2) with varying levels of INR control were compared to those who did not receive warfarin treatment using Cox proportional hazards models controlling for age, sex and CHADS2 score. Outcome measures were time to stroke and mortality. Results: 6,108 patients with NVAF were identified. 2,235 (36.6%) of these patients had five or more INR readings and of these 486 (21.7%) had CHADS2 score ≥2. There was significant improvement in time to stroke event in those patients with INR control of greater than 70% of time in therapeutic range (2.0 to 3.0) compared with the non-warfarin treatment group. Overall survival was significantly improved for all warfarin treated groups with INR control of greater than 40% of time in range. Conclusions: Patients with INR control of above 70% of time in range had a significantly reduced risk of stroke. Patient suitability for warfarin treatment should be continuously assessed based on their ability to maintain a consistently therapeutic INR. [Copyright &y& Elsevier]

Cardioembolic stroke accounts for one third of all ischemic strokes, and atrial fibrillation (AF) is the cardiac source of emboli in 50% of them. However, the absolute risk of stroke associated with AF has enormous variability, and several clinical risk stratification schemes have been proposed. One of the most validated and used in clinical practice is the CHADS2 index, characterized by its simplicity and rapid application. Current recommendations about antithrombotic therapy in AF patients are based on assessment of annual risk of stroke; thus, antiaggregation is indicated in patients with a low risk, and anticoagulation is prescribed when annual risk is greater than 2.5%. Relevant studies comparing rate and rhythm control do not defend achievement and maintenance of sinus rhythm as a routine management of AF patients and demonstrate that rate control is comparable or even better than rhythm control in terms of survival and quality of life. Optimal control of blood pressure is a relevant factor in preventing cardioembolic stroke in AF patients, because hypertension multiplies the risk of stroke by 12. Antihypertensive drugs such as angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers proved to reduce AF recurrences, especially in the context of left ventricular dysfunction and ventricular hypertrophy. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article presents an overview of the mechanisms involved with thrombogenesis in atrial fibrillation. Atrial fibrillation, the most common cardiac arrhythmia, is associated with the the risk of stroke and thromboembolism. Abnormal changes in the vessel walls including endocardial denudation and aedematous or fibroelastic infiltration of the extracellular matrix are discussed. Changes in the blood constituents including haemostatic and platelet activation and inflammation and growth factor changes comprise Virchow's triad for thrombogenesis.

Abstract: Objectives: This study examined compliance with prescribing guidelines for antithrombotic therapy in patients with atrial fibrillation (AF) in Taiwan, using the 2001 joint guideline from the American College of Cardiology, American Heart Association, and European Society of Cardiology. The study also sought to identify factors associated with the appropriate prescribing of antithrombotic therapy. Methods: Patients with AF were identified by the presence of ≥2 inpatient or outpatient claims with an International Classification of Diseases, Ninth Revision, Clinical Modification code of 427.31 in the Taiwanese National Health Insurance claims database between July 1, 2003, and June 30, 2004. Patients were stratified according to their stroke risk (highest, high, low, or lowest) and antithrombotic medication (aspirin, warfarin, ticlopidine/clopidogrel, or none). Based on these categories, rates of prescribed treatments that were compliant with the antithrombotic guidelines were calculated. Antithrombotic therapies were considered guideline compliant when warfarin was prescribed for the highest- or high-risk patients, aspirin was prescribed for low-risk patients, and aspirin or no antithrombotic treatment was prescribed for the lowest-risk patients. Because the role of ticlopidine/clopidogrel in AF remains unclear, prescription of these drugs without aspirin or warfarin was considered noncompliant with the guidelines. Results: Of 39,541 identified patients with AF, 70.3% were at high risk for thromboembolic events and 18.3% were at highest risk; however, only 24.7% of the overall population received appropriate antithrombotic therapy. When patients with risk factors for bleeding were excluded, the rate of compliance increased to 26.2%. Factors that were inversely associated with prescription of warfarin included risk factors for bleeding (cancer, predisposition to falls, previous hemorrhage, history of peptic ulcer, cirrhosis, renal dialysis, and psychiatric disease), hypertension, coronary artery disease, thyrotoxicosis, and age ≥60 years. Conclusions: Most of these patients with AF in Taiwan did not receive appropriate antithrombotic therapy over the period studied. Bleeding risk factors, hypertension, coronary artery disease, thyrotoxicosis, and older age were associated with low rates of warfarin use. [Copyright &y& Elsevier]

Abstract: Background: Although several risk factors for stroke have been reported in patients with atrial fibrillation (AF), the relation of LV diastolic dysfunction to stroke is still uncertain in these patients. We evaluated the relationship between tissue Doppler-derived index, E/E'', as well as other clinical and echocardiographic parameters and ischemic stroke by this cross-sectional study. Methods: Three hundred thirty patients with persistent AF who had preserved LV ejection fraction were included from 6 centers. Clinical data were obtained and standard transthoracic echocardiography was performed. Patients without a history of ischemic stroke (n =280) were compared with patients with this complication (n =50). Potential determinants of ischemic stroke were identified by logistic regression analyses. Results: In univariate analyses, age, history of hypertension, diabetes mellitus, hyperlipidemia and symptomatic heart failure, plasma brain natriuretic peptide (BNP) level, early mitral inflow velocity (E), diastolic mitral annular velocity (E''), and E/E'' ratio were significantly correlated to ischemic stroke. Multivariate regression analyses identified two significant variables that were independently associated with ischemic stroke: hypertension (odds ratio=6.03, p =0.008), and E/E'' (odds ratio=1.21, p =0.002). Conclusions: These findings may have clinical implications that LV diastolic dysfunction, reflected by E/E'', is a significant determinant of ischemic stroke in AF. A larger prospective data is needed to confirm the value of E/E'' in risk stratification for ischemic stroke in this population. [Copyright &y& Elsevier]

Background and aim: Published data suggest that patients with cerebral ischaemia and atrial fibrillation (CIAF( have higher inhospital mortality than patients with cerebral ischaemia of arterial origin (CIAO(. Data on long term risks are scarce. We compared the long term risks of death and vascular events (VE) between these groups. Methods: We extended the follow-up of 2473 patients from the Dutch TIA Trial (recruitment March 1986 to March 1989, all treated with aspirin; CIAO) and 186 Dutch participants of the European Atrial Fibrillation Trial (recruitment June 1988 to May 1992, 26% on anti- coagulants during the trial; CIAF(. Hazard ratios (HRs( for death and VE of CIAF versus CIAO were analysed by means of Cox regression analysis and adjusted for age, sex and several cardiovascular risk factors. Results: After a mean follow-up of 10.1 years, 1484 patients with CIAO had died and 1336 had suffered at least one VE (377 cardiac, 455 stroke(. Mean follow-up of the CIAF patients was 6.8 years; 150 patients had died and 136 had suffered at least one VE (41 cardiac, 63 stroke(. Adjusted HRs (CIAF vs CIAO) were 1.46 (95% Cl 1.22 to 1.741 for death, 1.49 (1.24 to 1.791 for first yE, 1.94 (1.47 to 2.55( for first stroke and 1.41 (1.01 to 1 .96( for first cardiac event. These HRs were essentially the same as those for the duration of the trials. Conclusion: Our study shows that the long term risk of death or vascular events is 1.5 times higher in patients with CIAF than in those with CIAO, after adjustment for differences between the groups. [ABSTRACT FROM AUTHOR]

Early neurological deterioration (END) in acute ischaemic stroke is a common event. The underlying mechanisms are heterogeneous. The clinical predictors of END include severity of the initial stroke, large vessel occlusion, diabetes mellitus, hypotension, and atrial fibrillation. Serial observations and detailed assessment by the trained staff in specialised stroke units are key to the successful management of these patients. Advances in brain and vascular imaging have provided insight into the underlying mechanisms, enabling clinicians to use preventative and therapeutic interventions specifically targeted at them, though several questions still remain unanswered. END has potentially serious consequences on the short term (morbidity and death) and long term (recovery from stroke) outcomes for the patient. Therefore, attempts to prevent and treat END should be made promptly and aggressively. [ABSTRACT FROM AUTHOR]

Background: Cerebrovascular disease is a major public health problem in both industrialized countries and developing nations. In Mexico there are not enough studies to know the epidemiological behaviour of this disease. Objectives: To describe and analyze epidemiological variables in a specific group of patients with cerebral vascular disease admitted to hospitals in Mexico City. Patients and methods: In a multicenter, retrospective and observational study, the coordinators of each school reviewed tomographic studies and clinical records of patients admitted in five hospitals in Mexico City with the diagnosis of cerebral vascular disease in 2005. The analysis included the following variables: age, gender and other cardiovascular risk factors such as hypertension, diabetes mellitus, smoking and atrial fibrillation. The prognosis was established as discharge due to improvement or death. Results: The diagnosis was made in 669 patients aged 39 to 99 years (mean: 72 years [SD 12.10]) Of these, 286 were women (42.7%). It was reported 488 cases of ischemic type (72.94%), 135 parenchymal haemorrhages (20.17%) and 46 subarachnoid haemorrhages (6.8%). The territory of the middle cerebral artery was the most commonly affected (84.30%) and systemic arterial hypertension was the most common risk factor in this group of patients. The average days of hospital stay was 9.87 (standard deviation: 9.57) and mortality was reported in 26% (174 patients). Conclusion: Our study provides epidemiological information of a new and reliable global public health problem. The ageing of our population coupled with the combination with other risk factors increase the frequency of cerebral vascular disease. [ABSTRACT FROM AUTHOR]

This article reports on a clinical trial that sought to compare the use of idraparinux to vitamin K antagonists to prevent thromboembolism in patients with atrial fibrillation. Non-valvular atrial fibrillation is the leading cause of stroke and studies have showed that anticoagulation with vitamin K antagonists can reduce the risk of stroke by a third. Despite that, the use of the drugs in clinical practice is limited due to the risk of bleeding and the complexity of monitoring the dosage. Researchers are hoping to find an unmonitored, fixed-dose anticoagulant that will be effective. This study was not the answer. It had to be stopped after patients getting the idrapariux bled excessively.

Atrial fibrillation (AF) is one of the most frequent cardiac arrhythmia and is associated with increased cardiovascular morbidity and mortality, and the risk of stroke. Although currently available antiarrhythmic drugs are moderately effective in restoring normal sinus rhythm in patients with AF, excessive delay of ventricular repolarization by these agents may be associated with increased risk of proarrhythmia. Therefore, selective blockers of cardiac ion channel(s) that are exclusively present in the atria are highly desirable. NIP-142 is a novel benzopyrane derivative, which blocks potassium, calcium, and sodium channels and shows atrial specific action potential duration prolongation. NIP-142 preferentially blocks the ultrarapid delayed rectifier potassium current (IKur) and the acetylcholine-activated potassium current (IKACh). Since IKur and IKACh have been shown to be expressed more abundantly in the atrial than in the ventricular myocardium, the atrial-specific repolarization prolonging effect of NIP-142 is considered to be due to the blockade of these potassium currents. In canine models, NIP-142 was shown to terminate the microreentry type AF induced by vagal nerve stimulation and the macroreentry type atrial flutter induced by an intercaval crush. These effects of NIP-142 have been attributed to the prolongation of atrial effective refractory period (ERP), because this compound prolonged atrial ERP without affecting intraatrial and interatrial conduction times in these models. The ERP prolongation by NIP-142 was greater in the atrium than in the ventricle. NIP-142 also terminated the focal activity type AF induced by aconitine. In addition, NIP-142 reversed the atrial ERP shortening and the loss of rate adaptation induced by short-term rapid atrial pacing in anesthetized dogs. Thus, although clinical trials are required to provide evidence for its efficacy and safety, the novel multiple ion channel blocker, NIP-142, appears to be a useful agent for the treatment of several types of AF with a low risk of proarrhythmic activity. [ABSTRACT FROM AUTHOR]

Objectives: non-valvular atrial fibrillation (NVAF) is an established risk factor for thromboembolism and stroke. Small cross-sectional studies suggest associations between NVAF, silent cerebral infarction and decreased cognitive function. We compared change in cognitive function between patients with recent onset NVAF and controls 12 and 36 months after baseline assessment, and examined the impact of anti-thrombotic therapy. Design: prospective longitudinal cohort study with follow-up at 12 and 36 months. Setting: Sunderland and South Tyneside, North East of England. Participants: community-dwelling men and women aged over 60 with recently identified NVAF or in sinus rhythm, matched for age, sex and general practice (N = 362, 174 NVAF, 188 sinus rhythm). Participants were stratified for use of anti-thrombotic therapy. Measurements: assessment included stroke risk factors and a comprehensive battery of neuropsychological tests. Results: at 3 years, 74 cases and 86 controls remained, giving an attrition rate for cases (59%) versus controls (52%);p = 0.15. Analysis of change in cognitive function between baseline and follow-up at 12 and 36 months revealed no clinically important differences between cases and controls, nor between subgroups on aspirin, warfarin or neither. Age and other confounders did not influence the results. Conclusions: there was no association between overall cognitive decline and NVAF after 3 years' follow-up, nor any apparent effect of anti-thrombotic therapy. This is consistent with our baseline results, but conflicts with previous studies. Cognitive decline is probably multifactorial and any influence of NVAF was not identified in this study. [ABSTRACT FROM AUTHOR]

The section presents abstracts of medical research on the risk factors of stroke. They include "Ho Well Can Primary Care Physicians, Nurses and Computer Software Detect Atrial Fibrillation on ECG?" "The Early Risk of Stroke After Vertebrobasilar TIA is High That After Carotid TIA" and "The Stroke Offspring Study (SOS): Stroke Risk Factors in the Offsrping of Stroke Patients."

Warfarin is underused for stroke prevention in atrial fibrillation (AF). Previous studies addressing this have lacked longitudinal assessment. This study sought to characterize contemporary warfarin use in new-onset AF and evaluate its change over time. It was hypothesized that AF recurrence has an important influence on warfarin use patterns. One thousand five adults from 17 centers in the United States and Canada were enrolled into a prospective observational registry after their first documented episodes of AF. Detailed demographic, clinical history, and management data were collected on all subjects at enrollment, including medication use. Patients were followed at regular intervals for interim events and changes in AF management. Warfarin use at baseline and last follow-up (mean 25 ± 8 months) after enrollment was modeled using multivariate analysis. Initially, 65% of subjects were prescribed warfarin, but only 44% were taking it at 30 months. Even in “ideal” candidates for warfarin, the rate of warfarin prescription decreased from 70% at baseline to 50% at 30 months. Stroke risk factors, including hypertension, congestive heart failure, valvular heart disease, and previous stroke or transient ischemic attack were significant predictors of warfarin prescription at baseline. At last follow-up, the relation between AF recurrence and warfarin use (odds ratio 2.3, 95% confidence interval 1.6 to 3.1) was stronger than that for any individual stroke risk factor. In conclusion, predictors of warfarin use in patients with AF include AF recurrence and selected stroke risk factors. The discontinuation of warfarin in a large number of patients with AF over time is a cause for concern in light of data from recent clinical trials. [Copyright &y& Elsevier]

Presents a case of a 60-year-old woman with two year history of paroxysmal atrial fibrillation which progressed into persistent AF. Definition and epidemiology of AF; Risk factors; Classification of AF; Clinical course of the disease; Risks and benefits of anticoagulation; Optimal intensity of anticoagulation; Best candidate for the therapy; The factors that influence the decision to take warfarin; Status of clinical research on AF; Recommendations for this patient; Questions and discussion with a cardiologist.

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

Using a Medicare-based retrospective cohort study, the stroke risk in patients with atrial flutter (RR = 1.41) was determined to be greater than that in a control group (RR = 1.00) but less than that in an atrial fibrillation group (RR = 1.64). Furthermore, patients with atrial flutter who subsequently had an episode of atrial fibrillation had a higher risk of stroke (RR = 1.56) than patients with atrial flutter who never had a subsequent episode of atrial fibrillation (RR = 1.11). [ABSTRACT FROM AUTHOR]

Objectives – To characterize the vascular risk factor profiles in different subtypes of ischemic stroke. Material and methods – The study population consisted of 1473 consecutive ischemic stroke patients collected in a prospective stroke registry. The prevalence of vascular risk factors in each stroke subtype was analyzed independently and in comparison with other subtypes of stroke pooled together by means of univariate analysis and logistic regression models. Results – Hypertension was present in 52% of patients followed by atrial fibrillation in 27% and diabetes in 20%. The pattern of risk factors associated with atherothrombotic stroke included chronic obstructive pulmonary disease (COPD) (odds ratio [OR]=2.63), hypertension (OR=2.55), diabetes (OR=2.26), transient ischemic attack (OR=1.61), and age (OR=1.03). Previous cerebral hemorrhage (OR=4.72), hypertension (OR=4.29), obesity (OR=2.45), and diabetes (OR=1.73) were strong predictors of lacunar stroke. In the case of cardioembolic stroke, atrial fibrillation (OR=22.24), valvular heart disease (OR=10.97), and female gender (OR=1.66) occurred more frequently among patients with this stroke subtype than among the other stroke subtypes combined. Conclusion – Different potentially modifiable vascular risk factor profiles were identified for each subtype of ischemic stroke, particularly COPD in the case of atherothrombotic stroke and previous cerebral hemorrhage and hypertension in the case of lacunar infarction. [ABSTRACT FROM AUTHOR]

Purpose: Atrial fibrillation is an important risk factor for stroke. We analyzed stroke risk over time in patients discharged from the hospital with a diagnosis of incident atrial fibrillation as compared with the risk of stroke in the Danish population.Subjects and Methods: In a random sample of half of the Danish population, we identified 13,625 men and 13,577 women, aged 50 to 89 years, with a hospital diagnosis of atrial fibrillation and no prior diagnosis of stroke during 1980 to 1993. Data on other medical conditions were also available from 1977 to 1993, but medication data were not available. Patients were followed from the diagnosis of atrial fibrillation until the first diagnosis of stroke (nonfatal or fatal cerebral ischemic infarct and cerebral hemorrhage), death, or the end of 1993. The risk of stroke in these patients was compared with the risk in the Danish population using Poisson regression modeling to estimate relative risks (RR) and 95% confidence intervals (CI).Results: For men with atrial fibrillation, the stroke rates increased by age, from 13 per 1,000 person-years in those ages 50 to 59 years, to 22 per 1,000 person-years in those ages 60 to 69 years, to 42 per 1,000 person-years in those ages 70 to 79 years, to 51 per 1,000 person-years in those ages 80 to 89 years. Age-specific stroke rates were similar in women with atrial fibrillation. Patients with a hospital diagnosis of atrial fibrillation had an increased risk of stroke (RR = 2.4; 95% CI, 2.3 to 2.5 in men and RR = 3.0; 95% CI, 2.9 to 3.2 in women) compared with the Danish population. Stroke risk was greatest during the first year after discharge and decreased thereafter. Hypertension, diabetes, and peripheral atherosclerosis were also associated with an increased risk of stroke among patients with atrial fibrillation. Ischemic heart disease and heart failure were risk factors in men only. There was no reduction in the risk of stroke from 1980 to 1993.Conclusions: Men and women with atrial fibrillation are at a substantially increased risk of stroke, particularly in the first year after the diagnosis. [ABSTRACT FROM AUTHOR]