Predictors of major vascular events in patients with a transient ischemic attack or minor ischemic stroke and with nonrheumatic atrial fibrillation. European Atrial Fibrillation Trial (EAFT) Study Group

Gender Predicts Differences in Acute Ischemic Cardioembolic Stroke Profile: Emphasis on Woman-Specific Clinical Data and Early Outcome-The Experience of Sagrat Cor Hospital of Barcelona Stroke Registry

Background and Objectives: Acute ischemic cardioembolic stroke (CS) is a clinical condition with a high risk of death, and can lead to dependence, recurrence, and dementia. Materials and Methods: In this study, we evaluated gender differences and female-specific clinical data and early outcomes in 602 women diagnosed with CS from a total of 4600 consecutive acute stroke patients in a single-center hospital stroke registry over 24 years. A comparative analysis was performed in women and men in terms of demographics, cerebrovascular risk factors, clinical data, and early outcomes. Results: In a multivariate analysis, age, hypertension, valvular heart disease, obesity, and internal capsule location were independent variables associated with CS in women. The overall in-hospital mortality rate was similar, but the group of women had a greater presence of neurological deficits and a higher percentage of severe limitation at hospital discharge. After the multivariate analysis, age, altered consciousness, limb weakness, and neurological, respiratory, gastrointestinal, renal, cardiac and peripheral vascular complications were independent predictors related to early mortality in women. Conclusions: Women with CS showed a differential demographic and clinical profile and worse early outcomes than men. Advanced age, impaired consciousness, and medical complications were predictors of stroke severity in women with CS.

The Role of HATCH Score in the Prediction of Ischemic Cerebrovascular Events in Patients with Heart Failure and Atrial Fibrillation

The presence of both atrial fibrillation (AF) and heart failure (HF) increases the risk of an ischemic cerebrovascular event (CVE) by roughly fivefold. The HATCH score is a score used to predict new-onset AF. Although there are some differences, it contains risk factors similar to the CHA2DS2-VASc score. Our study aimed to investigate the relationship between the HATCH score and ischemic CVE. This retrospective study obtained data from 1719 HF patients between 2015 and 2022. About 673 patients with AF were included in the study. In the univariate and multivariate Cox regressions, we found that CHA2DS2-VASc and HATCH scores were independent predictors of ischemic CVE (p = 0.001 and < p = 0.001, respectively). The ROC analysis, AUC for the CHA2DS2-VASc score was 0.884 (95% CI 0.828-0.940, Collapse

Key Words

• CHA2DS2-VASc score
• HATCH score
• atrial fibrillation
• heart failure
• ischemic stroke

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MESH Headings

• Humans
• Atrial Fibrillation/complications
• Stroke/etiology
• Retrospective Studies
• Risk Assessment
• Risk Factors
• Heart Failure/complications

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Affiliation(s)

Sidar Şiyar Aydın Department of Cardiology, University of Health Sciences, Erzurum Education and Research Hospital, Erzurum, Turkey
Emrah Aksakal Department of Cardiology, University of Health Sciences, Erzurum Education and Research Hospital, Erzurum, Turkey

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Ticagrelor or prasugrel vs. clopidogrel in patients with atrial fibrillation undergoing percutaneous coronary intervention for myocardial infarction

Aims

The efficacy and safety of ticagrelor or prasugrel vs. clopidogrel in patients with atrial fibrillation (AF) on oral anticoagulation (OAC) undergoing percutaneous coronary intervention (PCI) for myocardial infarction (MI) have not been established.

Methods and results

This was a nationwide cohort study of patients on OAC for AF who underwent PCI for MI from 2011 through 2019 and were prescribed a P2Y12 inhibitor at discharge. The primary efficacy outcome was major adverse cardiovascular events (MACE), defined as a composite of death from any cause, stroke, recurrent MI, or repeat revascularization. The primary safety outcome was cerebral, gastrointestinal, or urogenital bleeding requiring hospitalization. Absolute and relative risks for outcomes at 1 year were calculated through multivariable logistic regression with average treatment effect modelling. Outcomes were standardized for the individual components of the CHA2DS2-VASc and HAS-BLED scores as well as type of OAC, aspirin, and proton pump inhibitor use. We included 2259 patients of whom 1918 (84.9%) were prescribed clopidogrel and 341 (15.1%) ticagrelor or prasugrel. The standardized risk of MACE was significantly lower in the ticagrelor or prasugrel group compared with the clopidogrel group (standardized absolute risk, 16.3% vs. 19.4%; relative risk, 0.84, 95% confidence interval, 0.70-0.98; P = 0.02), while the risk of bleeding did not differ (standardized absolute risk, 5.5% vs. 5.1%; relative risk, 1.07, 95% confidence interval, 0.73-1.41; P = 0.69).

Conclusion

In patients with AF on OAC who underwent PCI for MI, treatment with ticagrelor or prasugrel vs. clopidogrel was associated with reduced ischaemic risk, without a concomitantly increased bleeding risk.

Screening and management of atrial fibrillation in primary care

Atrial fibrillation is a common chronic disease seen in primary care offices, emergency departments, inpatient hospital services, and many subspecialty practices. Atrial fibrillation care is complicated and multifaceted, and, at various points, clinicians may see it as a consequence and cause of multi-morbidity, as a silent driver of stroke risk, as a bellwether of an acute medical illness, or as a primary rhythm disturbance that requires targeted treatment. Primary care physicians in particular must navigate these priorities, perspectives, and resources to meet the needs of individual patients. This includes judicious use of diagnostic testing, thoughtful use of novel therapeutic agents and procedures, and providing access to subspecialty expertise. This review explores the epidemiology, screening, and risk assessment of atrial fibrillation, as well as management of its symptoms (rate and various rhythm control options) and stroke risk (anticoagulation and other treatments), and offers a model for the integration of the components of atrial fibrillation care.

Atrial Fibrillation in Older People: Concepts and Controversies

Atrial fibrillation (AF) is the commonest cardiac rhythm abnormality and has a significant disease burden. Amongst its devastating complications is stroke, the risk of which increases with age. The stroke risk in an older person with AF is therefore tremendous, and oral-anticoagulation (OAC) therapy is central to minimizing this risk. The presence of age-associated factors such as frailty and multi-morbidities add complexity to OAC prescription decisions in older patients and often, OAC is needlessly withheld from them despite a lack of evidence to support this practice. Generally, this is driven by an over-estimation of the bleeding risk. This review article provides an overview of the concepts and controversies in managing AF in older people, with respect to the existing evidence and current practice. A literature search was conducted on Pubmed and Cochrane using keywords, and relevant articles published by the 1st of May 2019 were included. The article will shed light on common misconceptions that appear to serve as rationale for precluding OAC and focus on clinical considerations that may aid OAC prescription decisions where appropriate, to optimize AF management using an integrated, multi-disciplinary care approach. This is crucial for all patients, particularly older individuals who are most vulnerable to the deleterious consequences of this condition.

Recent advances in the understanding and management of atrial fibrillation: a focus on stroke prevention

Atrial fibrillation (AF) is associated with an increased risk of stroke compared with the general population. It is anticipated that by 2030 an estimated 14-17 million patients will be diagnosed with this most prevalent arrhythmia within the European Union. AF-related stroke confers a higher mortality and morbidity risk, and thus early detection and assessment for the initiation of effective stroke prevention with oral anticoagulation (OAC) is crucial. Recent guidelines point to the use of non-vitamin K antagonist OACs (NOACs) where appropriate in stroke prevention of patients with non-valvular AF. At present, there are four NOACS available, with no direct head-to-head comparisons to suggest the superiority of one drug over another. Simple and practical risk assessment tools have evolved over the years to facilitate stroke and bleeding risk assessment in busy clinics and wards to aid decision-making. At present, the CHA ₂DS ₂VASc (congestive heart failure, hypertension, age 65-74/>75, diabetes mellitus, stroke/transient ischemic attack/thromboembolism, vascular disease, female sex) score is recommended by many international guidelines as a simple and practical method of assessing stroke risk in such patients. Alongside this, use of the HAS BLED (hypertension systolic blood pressure >160 mmHg, abnormal liver/renal function [with creatinine ≥200 μmol/L], stroke, bleeding history or predisposition, labile international normalized ratio [range <60% of the time], elderly [>65], concomitant drugs/alcohol) score aims to identify patients at high risk of bleeding for more regular review and follow-up and draws attention to potentially reversible bleeding risk factors. The aim of this review article is to provide an overview of recent advances in the understanding and management of AF with a focus on stroke prevention.

Blood pressure control and stroke or bleeding risk in anticoagulated patients with atrial fibrillation: Results from the ROCKET AF Trial

BACKGROUND

We conducted a retrospective analysis examining the association between systolic blood pressure (SBP) or hypertension bracket and stroke risk in patients with atrial fibrillation (AF).

METHODS

The study included 14,256 anticoagulated patients in the ROCKET AF trial. Cox proportional hazards models were used to compare the risk of adverse outcomes by European Society of Cardiology hypertension bracket and screening SBP.

RESULTS

In total, 90.5% of patients had hypertension (55.8% controlled, 34.6% uncontrolled). The adjusted risk of stroke or systemic embolism (SE) increased significantly for every 10-mm Hg increase in screening SBP (hazard ratio [HR] 1.07, 95% CI 1.02-1.13). There was a trend toward an increased adjusted risk of stroke or SE in patients with controlled (HR 1.22, 95% CI 0.89-1.66) and uncontrolled hypertension (HR 1.42, 95% CI 1.03-1.95) (P = .06). In contrast, the adjusted risk of major bleeding was similar between hypertensive brackets and did not vary significantly by screening SBP. The benefit of rivaroxaban versus warfarin in preventing stroke or SE was consistent among patients regardless of SBP (P interaction = .69).

CONCLUSIONS

In a trial of anticoagulated patients with AF, increasing screening SBP was independently associated with stroke and SE, and one-third of patients had uncontrolled hypertension. The relative effectiveness and safety of rivaroxaban versus warfarin were consistent across all levels of screening SBP. A single SBP may be an important factor in reducing the overall risk of stroke and SE in anticoagulated patients with AF.

Epidemiology, diagnosis, and management of atrial fibrillation in women

Atrial fibrillation (AF) is the most common arrhythmia and has become a serious public health problem. Moreover, epidemiological data demonstrate that incidence and prevalence of AF are increasing. Several differences in epidemiological patterns, clinical manifestations, and incidence of stroke have been reported between AF in women and in men, particularly in elderly women. Elderly women have higher blood pressure than men and a higher prevalence of heart failure with preserved ejection fraction, both independent risk factors for stroke. On the basis of the evidence on the higher stroke risk among AF in women, recently, female sex has been accepted as a risk factor for stroke and adopted to stratify patients, especially if they are not at high risk for stroke. This review focuses on available evidence on sex differences in AF patients, and examines factors contributing to different stroke risk, diagnosis, and prognosis of arrhythmia in women, with the aim to provide an analysis of the available evidence.

Is female sex a risk factor for stroke and thromboembolism in patients with atrial fibrillation? A systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) increases the risk of stroke, but this risk is not homogenous. Many risk factors contribute to stroke risk however, the evidence for female sex as a risk factor is less well-established.

AIM

To perform a systematic review and meta-analysis of the available evidence to establish if female sex is a risk factor for stroke/thromboembolism among patients with AF.

METHODS

A systematic literature search was conducted using Medline. The search term 'atrial fibrillation' was used in combination with 'stroke risk', 'thromboembolism', 'female' and 'gender differences' and returned 735 articles, of which 17 were appraised and included. Females with AF were compared with males with AF for the outcome of stroke/thromboembolism.

RESULTS

Seventeen studies, 5 randomized-controlled trials and 12 prospective observational studies were included; 10 demonstrated an increased risk of stroke in women. Meta-analysis of the 17 studies revealed a 1.31-fold (95% confidence intervals (CIs) 1.18-1.46) elevated risk of stroke in women with AF; the risk appearing greatest for women aged ≥75 years. Only three studies compared entirely anticoagulated populations; stroke rates among these patients varied from 1.2-1.44% per-patient year for men and 2.08-2.43% per-patient year for women. Risk of stroke in women appeared similar regardless of oral anticoagulation therapy [risk ratio (95% CI 1.29 (1.09-1.52) and 1.49 (1.17-1.90) in non-anticogulated vs. anticoagulated/mixed cohorts, respectively).

CONCLUSIONS

Women with AF are at increased risk of stroke, particularly elderly women. Comprehensive stroke risk assessment, including sex as a risk factor, should be undertaken in all AF patients.

Safe use of antithrombotics for stroke prevention in atrial fibrillation: consideration of risk assessment tools to support decision-making

Clinical guidelines advocate stroke prevention therapy in atrial fibrillation (AF) patients, specifically anticoagulation. However, the decision to initiate treatment is based on the risk (bleeding) versus benefit (prevention of stroke) of therapy, which is often difficult to assess. This review identifies available risk assessment tools to facilitate the safe and optimal use of antithrombotic therapy for stroke prevention in AF. Using key databases and online clinical resources to search the literature (1992-2012), 19 tools have been identified and published to date: 11 addressing stroke risk, 7 addressing bleeding risk and 1 integrating both risk assessments. The stroke risk assessment tools (e.g. CHADS2, CHA2DS2-VASc) share common risk factors: age, hypertension, previous cerebrovascular attack. The bleeding risk assessment tools (e.g. HEMORR2HAGES, HAS-BLED) share common risk factors: age, previous bleeding, renal and liver impairment. In terms of their development, six of the stroke risk assessment tools have been derived from clinical studies, whilst five are based on refinement of existing tools or expert consensus. Many have been evaluated by prospective application to data from real patient cohorts. Bleeding risk assessment tools have been derived from trials, or generated from patient data and then validated via further studies. One identified tool (i.e. Computerised Antithrombotic Risk Assessment Tool [CARAT]) integrates both stroke and bleeding, and specifically considers other key factors in decision-making regarding antithrombotic therapy, particularly those increasing the risk of medication misadventure with treatment (e.g. function, drug interactions, medication adherence). This highlights that whilst separate tools are available to assess stroke and bleeding risk, they do not estimate the relative risk versus benefit of treatment in an individual patient nor consider key medication safety aspects. More effort is needed to synthesize these separate risk assessments and integrate key medication safety issues, particularly since the introduction of new anticoagulants into practice.

Prediction and prevention of stroke after transient ischemic attack in the short and long term

Over the last 5 years, a number of studies have shown the early risk of stroke following transient ischemic attack (TIA) to be of the order of 5-10% at 1 week and 10-20% at 3 months, considerably higher than previously estimated. Because these studies have been carried out in a variety of different clinical settings, their findings are likely to be generalizable. Various independent prognostic factors for this early risk of stroke have been identified and models, based on clinical features at presentation, have been derived and validated to predict risk of stroke within 7 and 90 days after TIA. At the same time, diffusion-weighted magnetic resonance imaging and carotid imaging provide prognostic information and are likely to refine risk prediction further, although no unified model combining clinical and imaging data currently exists. Uncertainty continues surrounding the most effective secondary prevention in the hyperacute phase after TIA, especially in the choice of antiplatelet agents, although clinical trials to address this question are ongoing. However, the need for carotid endarterectomy in patients with symptomatic carotid stenosis is well established. The risk of vascular disease in the medium term (1-5 years) following TIA has been more widely studied, and predictive models for this are available. Recent data on the long-term (10 years and beyond) vascular risk after TIA demonstrate ongoing mortality from both cerebrovascular and cardiovascular causes, highlighting the need for continued secondary prevention.

Prediction of congestive heart failure in patients with non valvular atrial fibrillation

OBJECTIVE

Patients with atrial fibrillation (AF) have an increased risk of congestive heart failure (CHF) as well as ischemic stroke. The aim of this study was to investigate the clinical predictors of CHF in patients with non-valvular AF (NVAF).

METHODS

Three hundred and forty-seven patients (derivation cohort) with NVAF were retrospectively evaluated between 2004 and 2005. The associations between potential risk factors and CHF were tested using a Cox proportional hazards analysis, and a risk score for predicting CHF was created. The model was then validated in 161 patients (validation cohort) enrolled between 2008 and 2010. During the follow-up period, 41 patients in the derivation cohort developed CHF requiring hospitalization due to New York Heart Association (NYHA) class III or IV disease. Four independent risk factors were identified, each of which was assigned a number of points as follows: Age ≥72 years (1 point), heart rate ≥80 bpm (1 point), hypertension (1 point), and a previous history of congestive heart failure (2 points). The patients were grouped into one of three risk categories according to the calculated risk score (ARC2H score): low risk (0 points), intermediate risk (1-3 points) and high risk (4-5 points).

RESULT

In the derivation cohort, the annual rates of CHF in these risk categories were 0%, 2.5% and 18% per year respectively. In the validation cohort, the corresponding rates were 0.8%, 8% and 35% per year respectively.

CONCLUSION

A simple clinical risk score, the ARC2H score, was developed to predict CHF in patients with NVAF and validated in an independent cohort.

Acute cardioembolic cerebral infarction: answers to clinical questions

Cardioembolic cerebral infarction (CI) is the most severe subtype of ischaemic stroke but some clinical aspects of this condition are still unclear. This article provides the reader with an overview and up-date of relevant aspects related to clinical features, specific cardiac disorders and prognosis of CI. CI accounts for 14-30% of ischemic strokes; patients with CI are prone to early and long-term stroke recurrence, although recurrences may be preventable by appropriate treatment during the acute phase and strict control at follow-up. Certain clinical features are suggestive of CI, including sudden onset to maximal deficit, decreased level of consciousness at onset, Wernicke's aphasia or global aphasia without hemiparesis, a Valsalva manoeuvre at the time of stroke onset, and co-occurrence of cerebral and systemic emboli. Lacunar clinical presentations, a lacunar infarct and especially multiple lacunar infarcts, make cardioembolic origin unlikely. The most common disorders associated with a high risk of cardioembolism include atrial fibrillation, recent myocardial infarction, mechanical prosthetic valve, dilated myocardiopathy and mitral rheumatic stenosis. Patent foramen ovale and complex atheromatosis of the aortic arch are potentially emerging sources of cardioembolic infarction. Mitral annular calcification can be a marker of complex aortic atheroma in stroke patients of unkown etiology. Transthoracic and transesophageal echocardiogram can disclose structural heart diseases. Paroxysmal atrial dysrhythmia can be detected by Holter monitoring. Magnetic resonance imaging, transcranial Doppler, and electrophysiological studies are useful to document the source of cardioembolism. In-hospital mortality in cardioembolic stroke (27.3%, in our series) is the highest as compared with other subtypes of cerebral infarction. Secondary prevention with anticoagulants should be started immediately if possible in patients at high risk for recurrent cardioembolic stroke in which contraindications, such as falls, poor compliance, uncontrolled epilepsy or gastrointestinal bleeding are absent. Dabigatran has been shown to be non-inferior to warfarin in the prevention of stroke or systemic embolism. All significant structural defects, such as atrial septal defects, vegetations on valve or severe aortic disease should be treated. Aspirin is recommended in stroke patients with a patent foramen ovale and indications of closure should be individualized. CI is an important topic in the frontier between cardiology and vascular neurology, occurs frequently in daily practice, has a high impact for patients, and health care systems and merits an update review of current clinical issues, advances and controversies.

Atherosclerosis and thromboembolic risk in atrial fibrillation: focus on peripheral vascular disease

Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. It results in a 5-fold increased risk for stroke and thromboembolism and is associated with a high morbidity and mortality. AF shares several risk factors and pathophysiological features with atherosclerosis. Hence AF is often complicated by a variety of other cardiovascular conditions. Indeed, peripheral vascular disease (PVD) is highly prevalent among AF patients and associates with increased mortality. Inclusion of PVD within stroke risk scoring systems such as the CHA2DS2-VASc score improves risk stratification of AF patients. Of note, PVD has not been previously well documented nor looked for in observational studies or clinical trials. The aim of this present review article is to provide an overview of the association between atherosclerosis (with particular focus on PVD) and AF as well as its complications.

AF and Venous Thromboembolism - Pathophysiology, Risk Assessment and CHADS-VASc score

Atrial fibrillation (AF) and venous thromboembolism (VTE) are the two most common medical conditions managed with anti-coagulation therapy. Not all the patients with decreased mobility or AF have a similar risk for thromboembolism. The risk factors for venous thromboembolism and thromboembolism associated with AF are described in various studies. Considering that the two conditions have similar pathophysiologic basis of clot formation, one could imply that the risk factors for the occurrence of thrombosis could be similar. The present review focuses on the similarities and differences in the clinical risk factors of VTE and AF related thromboembolism. We will also be discussing the role of CHADS₂-VASc scoring system in the risk assessment of VTE.

The risk stratification in atrial fibrillation

Atrial fibrillation (AF) is the most common rhythm disorder and represents a major public health problem because it carries an increased risk of arterial thromboembolism and ischemic stroke. Because the absolute benefit of antithrombotic therapy depends on the underlying risk of stroke, an accurate stratification of patients' risk is needed to choose the appropriate antithrombotic strategy. Over the years, several stroke risk stratification models (RSMs) were developed based on the 'classic' risk factors for stroke such as increasing age, hypertension, diabetes mellitus, and left ventricular dysfunction. Among all RSMs, the CHADS(2) score is the most popular and used one thanks to its simplicity and endorsement in several widely promulgated practice guidelines. Despite its validation in large datasets and specific population of AF patients, it has many limitations, especially due to the non-inclusion of several proven risk factors for stroke and to the classification of a large number of patients in the intermediate risk category, so creating ambiguity over the most appropriate antithrombotic therapy. Thus, the CHA(2)DS(2)-VASc score was introduced and was demonstrated to perform better than the CHADS(2), even in a "real world" population of elderly AF patients. Recently, in view of the availability of new oral anticoagulant drugs, that can overcome the limitations of warfarin and allow a more personalized therapy, many efforts are being made to identify other possibilities to assess the thromboembolic risk in AF patients. It has been demonstrated that an increase in C-reactive protein and interleukin-6 and the presence of G20210A factor II gene polymorphism and hyper-homocysteinemia are independent risk factors for ischemic complications in AF patients. Even the presence of chronic renal disease and the daily AF burden, registered with implantable monitors, are associated with an increase risk of stroke. Finally, the assessment of thromboembolic risk should go hand in hand with the consideration of the risk of bleeding. For this purpose, it has been recently developed a practical bleeding risk score, the HAS-BLED, which was included in the last ESC guidelines for the risk stratification of AF patients before starting anticoagulant therapy.

Antithrombotic therapy for atrial fibrillation: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

The risk of stroke varies considerably across different groups of patients with atrial fibrillation (AF). Antithrombotic prophylaxis for stroke is associated with an increased risk of bleeding. We provide recommendations for antithrombotic treatment based on net clinical benefit for patients with AF at varying levels of stroke risk and in a number of common clinical scenarios.

METHODS

We used the methods described in the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines article of this supplement.

RESULTS

For patients with nonrheumatic AF, including those with paroxysmal AF, who are (1) at low risk of stroke (eg, CHADS(2) [congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke or transient ischemic attack] score of 0), we suggest no therapy rather than antithrombotic therapy, and for patients choosing antithrombotic therapy, we suggest aspirin rather than oral anticoagulation or combination therapy with aspirin and clopidogrel; (2) at intermediate risk of stroke (eg, CHADS(2) score of 1), we recommend oral anticoagulation rather than no therapy, and we suggest oral anticoagulation rather than aspirin or combination therapy with aspirin and clopidogrel; and (3) at high risk of stroke (eg, CHADS(2) score of ≥ 2), we recommend oral anticoagulation rather than no therapy, aspirin, or combination therapy with aspirin and clopidogrel. Where we recommend or suggest in favor of oral anticoagulation, we suggest dabigatran 150 mg bid rather than adjusted-dose vitamin K antagonist therapy.

CONCLUSIONS

Oral anticoagulation is the optimal choice of antithrombotic therapy for patients with AF at high risk of stroke (CHADS(2) score of ≥ 2). At lower levels of stroke risk, antithrombotic treatment decisions will require a more individualized approach.

Cardioembolic stroke: clinical features, specific cardiac disorders and prognosis

This article provides the reader with an overview and up-date of clinical features, specific cardiac disorders and prognosis of cardioembolic stroke. Cardioembolic stroke accounts for 14-30% of ischemic strokes and, in general, is a severe condition; patients with cardioembolic infarction are prone to early and long-term stroke recurrence, although recurrences may be preventable by appropriate treatment during the acute phase and strict control at follow-up. Certain clinical features are suggestive of cardioembolic infarction, including sudden onset to maximal deficit, decreased level of consciousness at onset, Wernicke’s aphasia or global aphasia without hemiparesis, a Valsalva manoeuvre at the time of stroke onset, and co-occurrence of cerebral and systemic emboli. Lacunar clinical presentations, a lacunar infarct and especially multiple lacunar infarcts, make cardioembolic origin unlikely. The more common high risk cardioembolic conditions are atrial fibrillation, recent myocardial infarction, mechanical prosthetic valve, dilated myocardiopathy, and mitral rheumatic stenosis. Transthoracic and transesophageal echocardiogram can disclose structural heart diseases. Paroxysmal atrial dysrhyhtmia can be detected by Holter monitoring. In-hospital mortality in cardioembolic stroke (27.3%, in our series) is the highest as compared with other subtypes of cerebral infarction. In our experience, in-hospital mortality in patients with early embolic recurrence (within the first 7 days) was 77%. Patients with alcohol abuse, hypertension, valvular heart disease, nausea and vomiting, and previous cerebral infarction are at increased risk of early recurrent systemic embolization. Secondary prevention with anticoagulants should be started immediately if possible in patients at high risk for recurrent cardioembolic stroke in which contraindications, such as falls, poor compliance, uncontrolled epilepsy or gastrointestinal bleeding are absent.

Intracranial collateralization determines hemodynamic forces for carotid plaque disruption

INTRODUCTION

Percent diameter reduction provides an imperfect assessment of the risk for stroke from carotid atheroembolism. Stroke associated with atherosclerotic carotid stenosis commonly results from plaque disruption brought about by hemodynamic shear stress and Bernoulli forces. The aim of the present study was to predict the effect of incomplete intracranial collateralization through the circle of Willis (COW) on disruptive hemodynamic forces acting on carotid plaques.

METHODS

A simple circuit model of the major pathways and collaterals that form and supply the COW was developed. We modeled the intra- and extracranial arterial circuits from standard anatomic references, and the pressure-flow relationships within these conduits from standard fluid mechanics. The pressure drop caused by (laminar and turbulent) flow along the internal carotid artery path was then computed. Carotid circulation to the brain was classified as being with or without collateral connections through the COW, and the extracranial carotid circuit as being with or without severe stenosis. The pressure drop was computed for each scenario. Finally, a linear circuit model was used to compute brain blood flow in the presence/absence of a disconnected COW.

RESULTS

Pressure drop across a carotid artery stenosis increased as the flow rate within the carotid conduit increased. Poststenotic turbulence from a sudden expansion distal to the stenosis resulted in an additional pressure drop. Despite the stenosis, mean brain blood flow was sustained at 4.15 mL/s bilaterally. In the presence of an intact (collateralized) COW, this was achieved by enhanced flow in the contralateral (normal) carotid artery. However, in a disconnected COW, this was achieved by sustained systolic and enhanced diastolic flow through the stenosed artery. For a similar degree of stenosis, flow and velocity across the plaque was much higher when the COW was disconnected compared with an intact COW. Furthermore, the pressure drop across a similar stenosis was significantly higher with a disconnected COW compared with an intact COW.

CONCLUSIONS

Incomplete intracranial collateralization through the COW results in increased flow rates and velocities, and therefore large pressure drops across a carotid artery stenosis. This exerts large disruptive shear stress on the plaque compared with patients with an intact COW. Percent diameter reduction provides an inaccurate assessment of risk for atheroembolic stroke. An assessment of carotid flow rates, flow velocities, and the intracranial collateral circulation may add independent information to refine the estimation of stroke risk in patients with asymptomatic carotid atherosclerosis.

The Link between Atrial Fibrillation and Stroke in Women

Atrial fibrillation (AF) is the most common clinically significant cardiac arrhythmia. The most serious complication of AF is thromboembolic stroke. The individual risk of stroke in the setting of AF varies. Several clinical factors have been identified as independent predictors of stroke in AF, including prior stroke, age, hypertension and diabetes. The bulk of available data identifies female gender as another independent predictor of stroke risk in AF. In this article, we review the link between AF and an elevated stroke risk in women, explore the potential pathophysiologic basis for this association and examine the data regarding the effectiveness of anticoagulation in reducing this risk.

A comparison of risk stratification schemes for stroke in 79,884 atrial fibrillation patients in general practice

BACKGROUND

Anticoagulation management of patients with atrial fibrillation (AF) should be tailored individually on the basis of ischemic stroke risk. The objective of this study was to compare the predictive ability of 15 published stratification schemes for stroke risk in actual clinical practice in the UK.

METHODS

AF patients aged ≥ 18 years in the General Practice Research Database, which contains computerized medical records, were included. The c-statistic was estimated to determine the predictive ability for stroke for each scheme. Outcomes included stroke, hospitalizations for stroke, and death resulting from stroke (as recorded on death certificates).

RESULTS

The study cohort included 79,844 AF patients followed for an average of 4 years (average of 2.4 years up to the start of warfarin therapy). All risk schemes had modest discriminatory ability in AF patients, with c-statistics for predicting events ranging from 0.55 to 0.69 for strokes recorded by the general practitioner or in hospital, from 0.56 to 0.69 for stroke hospitalizations, and from 0.56 to 0.78 for death resulting from stroke as reported on death certificates. The proportion of patients assigned to individual risk categories varied widely across the schemes, with the proportion categorized as moderate risk ranging from 12.7% (CHA(2) DS(2)-VASc) to 61.5% (modified CHADS(2)). Low-risk subjects were truly low risk (with annual stroke events < 0.5%) with the modified CHADS(2), National Institute for Health and Clinical Excellence and CHA(2) DS(2) -VASc schemes.

CONCLUSION

Current published risk schemes have modest predictive value for stroke. A new scheme (CHA(2) DS(2) -VASc) may discriminate those at truly low risk and minimize classification of subjects as intermediate/moderate risk. This approach would simplify our approach to stroke risk stratification and improve decision-making for thromboprophylaxis in patients with AF.

What is the role of the cardiologist in future management of stroke prevention in atrial fibrillation?

Atrial fibrillation (AF) is becoming increasingly common in an ageing population. Much of the morbidity and mortality in AF is due to stroke and thromboembolism. Awareness of stroke risk and the need for prevention is well recognized but is far from satisfactory in the real world. Despite refinements in the risk stratification over the years, there is an unmet need for appropriate thromboprophylaxis due to the underuse of oral anticoagulation. Primary care physicians and generalists bear the burden of managing AF. Coordinated multidisciplinary efforts by cardiologists, primary care physicians, and neurologists may be needed to meet the increasing challenge of stroke prevention and rhythm management in AF. This article discusses the potential the role of the cardiologist in the management of stroke prevention in patients with AF.

CHADS2 Score is a Poor Predictor of Non-cerebral Acute Arterial Occlusion in Patients with Non-valvular Atrial Fibrillation

OBJECTIVE

The CHADS2 score is a stroke risk stratification scheme in patients with non-valvular atrial fibrillation (NVAF). The aim of this study was to determine whether the CHADS2 score can help to predict the risk of non-cerebral acute arterial embolism.

MATERIALS AND METHODS

One hundred and seventeen patients who underwent surgery for non-cerebral acute arterial embolism with NVAF between 1997 and 2009 were enrolled in the cross sectional study. The CHADS2 score of each patient was calculated at the onset of symptoms. The distribution of the CHADS2 score was compared with that of other studies analyzing patients with stroke.

RESULTS

The perioperative mortality was 11.1%. A comparison of patients with stroke revealed that our distribution curves were significantly shifted to the left, showing that the CHADS2 score did better in predicting stroke than non-cerebral embolism. On the other hand, the distribution in our series coincides with that of NVAF patients in general. These results indicated that the risk of non-cerebral embolism occurs at the same rate regardless of the CHADS2 score.

CONCLUSIONS

The CHADS2 scoring system seems to be an unreliable predictor of non-cerebral embolism, and may not contribute in avoiding potentially life-threatening acute arterial occlusion of the peripheral artery.

Warfarin use associates with increased risk for stroke in hemodialysis patients with atrial fibrillation

Use of warfarin, clopidogrel, or aspirin associates with mortality among patients with ESRD, but the risk-benefit ratio may depend on underlying comorbidities. Here, we investigated the association between these medications and new stroke, mortality, and hospitalization in a retrospective cohort analysis of 1671 incident hemodialysis patients with preexisting atrial fibrillation. We followed patient outcomes from the time of initiation of dialysis for an average of 1.6 yr. Compared with nonuse, warfarin use associated with a significantly increased risk for new stroke (hazard ratio 1.93; 95% confidence interval 1.29 to 2.90); clopidogrel or aspirin use did not associate with increased risk for new stroke. Analysis using international normalized ratio (INR) suggested a dose-response relationship between the degree of anticoagulation and new stroke in patients on warfarin (P = 0.02 for trend). Warfarin users who received no INR monitoring in the first 90 d of dialysis had the highest risk for stroke compared with nonusers (hazard ratio 2.79; 95% confidence interval 1.65 to 4.70). Warfarin use did not associate with statistically significant increases in all-cause mortality or hospitalization. In conclusion, warfarin use among patients with both ESRD and atrial fibrillation associates with an increased risk for stroke. The risk is greatest in warfarin users who do not receive in-facility INR monitoring.

Tissue factor expression in the symptomatic carotid plaque

Background

The aims of this study were to identify that the differences in the natural history of patients with symptomatic and asymptomatic carotid stenosis may be reflected in differences in the expression of procoagulant protein factors.

Methods

Carotid artery plaques were obtained from 33 symptomatic and 4 asymptomatic patients with internal carotid artery stenosis of greater than 70%. These plaques were stained with monoclonal antibody against human tissue factor. Areas of staining for the cap and core were analysed using the analySIS computer programme.

Results

There were 37 patients, of whom 27 were male with a mean age 69.3 years and a range of 53 to 83 years. Statistical analysis using non-parametric tests revealed a significant increase in the area of positive staining for tissue factor in plaques taken from symptomatic patients when compared to those who were asymptomatic (P = 0001). Within the symptomatic patients group there was significantly increased tissue factor in the plaque core of those who were the most recently symptomatic (P = 0.003).

Conclusions

The unstable carotid artery plaque is associated with significantly increased tissue factor expression in the cap and core. Plaques from the most recently symptomatic patients have significantly more tissue factor in the core and this may represent part of the mechanism responsible for plaque destabilisation. More research is needed in this important area.

Keywords

Tissue Factor; Carotid stenosis; Stroke; Plaque stability

Interventions in the management of serum lipids for preventing stroke recurrence

BACKGROUND

Studies have shown that interventions which reduce total and low-density lipoprotein cholesterol levels also reduce coronary heart disease (CHD) and stroke events in those with a history of CHD. However, it is uncertain whether treatment to alter cholesterol levels can prevent recurrence of either stroke or subsequent cardiovascular events and whether differences in outcomes exist between classes of lipid-lowering therapy. This is an update of a Cochrane review first published in 2002.

OBJECTIVES

To investigate the effect of altering serum lipids pharmacologically for preventing subsequent cardiovascular disease and stroke recurrence in patients with a history of stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched December 2008), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2008), MEDLINE (1966 to December 2008) and EMBASE (1980 to December 2008). We contacted pharmaceutical companies known to produce a lipid-lowering agent for information on relevant publications or unpublished work.

SELECTION CRITERIA

Unconfounded randomised trials of participants aged 18 years and over with a history of stroke or transient ischaemic attack (TIA).

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed quality and extracted data.

MAIN RESULTS

We included eight studies involving approximately 10,000 participants. The active interventions were pravastatin, atorvastatin, simvastatin, clofibrate, and conjugated oestrogen. Fixed-effect analysis showed no overall effect on stroke recurrence but statin therapy alone had a marginal benefit in reducing subsequent cerebrovascular events in those with a previous history of stroke or TIA (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.77 to 1.00). There was no evidence that such intervention reduced all-cause mortality or sudden death (OR 1.00, 95% CI 0.83 to 1.20). Three statin trials showed a reduction in subsequent serious vascular events (OR 0.74, 95% CI 0.67 to 0.82).

AUTHORS' CONCLUSIONS

There is evidence that statin therapy in patients with a history of ischaemic stroke or TIA significantly reduces subsequent major coronary events but only marginally reduces the risk of stroke recurrence. There is no clear evidence of beneficial effect from statins in those with previous haemorrhagic stroke and it is unclear whether statins should be started immediately post stroke or later. In view of this and the evidence of the benefit of statin therapy in those with a history of CHD, patients with ischaemic stroke or TIA, with or without a history of established CHD, should receive statins.

Secondary prognosis after cardioembolic stroke of atrial origin: the role of left atrial and left atrial appendage dysfunction

BACKGROUND

Secondary prevention studies for cardioembolic strokes show a remarkable variability in stroke recurrence rates. Various reports have raised questions regarding differences in baseline clinical characteristics and in methodology to explain this wide variability.

HYPOTHESIS

The purpose of the present study is to examine the 2-year outcome after first cardioembolic stroke of atrial origin and to correlate secondary prognosis with left atrial and left atrial appendage dysfunction.

METHODS

Baseline evaluation included computed tomographic and/or magnetic resonance scanning, Doppler scanning, digital subtraction angiography, and transthoracic and transesophageal echocardiography to establish the diagnosis of atrial source of emboli. Twenty-six patients in nonrheumatic atrial fibrillation and 13 in sinus rhythm were followed for recurrent stroke and vascular death as endpoints (event +/-).

RESULTS

Patients in sinus rhythm had a total of 23% (standard deviation +/- 12%) recurrence rate. All event (+) patients were on aspirin and died from this second cardioembolic stroke. Of patients in nonrheumatic atrial fibrillation, 50% were event (+) at the end of the first year (death rate 46%). Patients on warfarin therapy had 20% recurrence rate versus 70% on aspirin (relative risk 0, 18, 95% confidence interval, 0.05-0.48, p 0.041). Inward peak velocity of left atrial appendage was the only echocardiographic variable significantly reduced in event (+) patients (21 +/- 7 vs. 31 +/- 17 cm/s, p 0.048).

CONCLUSIONS

Patients with nonrheumatic atrial fibrillation and first atrial origin cardioembolic stroke are at increased risk for recurrence if severe dysfunction of the left atrial appendage is present and if they do not receive warfarin treatment. Patients with sinus rhythm and first atrial origin cardioembolic stroke form a small stroke subgroup, in which recurrences are accompanied by a remarkably high death rate.

Interventions in the management of serum lipids for preventing stroke recurrence

BACKGROUND

A close association between serum lipid levels and the incidence of coronary heart disease (CHD) has been well proven in middle aged and older persons, up to the age of 70-75 years. Individual studies have shown interventions to reduce total and low density lipoprotein (LDL) cholesterol levels, especially with 3-hydroxy-3-methylglutaryl coenzyme a (HMG-CoA) reductase inhibitors (statins), to be of benefit in reducing CHD and stroke events in those with a history of coronary heart disease. However, the relation of serum cholesterol and cholesterol sub-fractions with cerebrovascular disease is less clear. It is unclear whether lipid levels in the post-stroke period are a predictor of recurrence and whether treatment to alter levels can prevent recurrence of either stroke or cardiovascular events.

OBJECTIVES

To investigate the effect of altering serum lipids in the prevention of cardiovascular disease and stroke recurrence in subjects with a history of stroke.

SEARCH STRATEGY

The Cochrane Group Trials Register was searched up to 8 May 2001 along with MEDLINE (from 1966), EMBASE (from 1980) and the Cochrane Controlled Trials Register. All pharmaceutical firms known to produce a lipid lowering agent were also contacted and asked to provide information on publications or unpublished work relevant to this review.

SELECTION CRITERIA

This review included unconfounded randomised trials of subjects aged 18 years and over with a history of stroke or Transient Ischaemic Attack (TIA).

DATA COLLECTION AND ANALYSIS

The data were extracted independently by the three reviewers. MetaView 4.1 was used for all statistical analyses.

MAIN RESULTS

Five studies involving 1700 patients were included in the review. The active intervention in two of the studies was Clofibrate, Pravastatin in another two and Conjugated Oestrogen in the fifth. Fixed effects analysis showed no evidence of a difference in stroke recurrence between the treatment and placebo groups for those with a previous history of stroke or TIA (odds ratio 0.96, 95% confidence interval 0.71 to 1.30). In addition there was also no evidence, based on two studies, that intervention reduced the odds of all cause mortality (odds ratio 0.87, 95% confidence interval 0.55 to 1.39) nor, from one study, that there was any effect on subsequent vascular events (odds ratio 1.27, 95% confidence interval 0.84 to 1.89).

REVIEWER'S CONCLUSIONS

These trials do not provide evidence for a benefit, or harm, from interventions to alter serum lipid levels in patients with a history solely of cerebrovascular disease. Their use, therefore, cannot yet be recommended routinely in this patient group, but ischaemic stroke patients with a history of myocardial infarction should receive statin therapy along the lines of the previous recommendations for those patients with a history of myocardial ischaemia. There are currently three ongoing trials which will recruit approximately 30,000 patients, including those with a history of stroke, and the results of these trials may have a significant effect on these conclusions.

A European view on the North American fifth consensus on antithrombotic therapy

An American-Canadian group of experts have, in the November 1998 issue of CHEST, published for the fifth time their recommendations for antithrombotic therapy. This remarkable consensus document was the result of an extensive review of the literature by an interdisciplinary group. Considering the impact of this document on medical practice, also outside North America, a group of European experts reviewed in detail the fifth report, particularly the sections on clinical indications of antithrombotic treatment. The aim was not to indicate the many areas of agreement and to quote literature that has become available since publication of the last consensus documents, but rather to refer to the gray zones of uncertainty and limited number of divergent opinions.

Atrial fibrillation and stroke: clinical presentation of cardioembolic versus atherothrombotic infarction

The aim of the study was to compare demographic characteristics, anamnestic findings, cerebrovascular risk factors, and clinical and neuroimaging data of cardioembolic stroke patients with and without atrial fibrillation and of atherothrombotic stroke patients with and without atrial fibrillation. Predictors of early diagnosis of cardioembolic vs. atherothrombotic stroke infarction in atrial fibrillation patients were also determined. Data of cardioembolic stroke patients with (n=266) and without (n=81) atrial fibrillation and of atherothrombotic stroke patients with (n=75) and without (n=377) were obtained from 2000 consecutive patients included in the prospective Sagrat Cor-Alianza Hospital of Barcelona Stroke Registry. Risk factors, clinical characteristics and neuroimaging features in these subgroups were compared. The independent predictive value of each variable on early diagnosis of stroke subtype was assessed with a logistic regression analysis. In-hospital mortality in patients with atrial fibrillation was significantly higher than in non-atrial fibrillation patients both in cardioembolic (32.6% vs. 14.8%, P<0. 005) and atherothrombotic stroke (29.3% vs. 18.8%, P<0.04). Valvular heart disease (odds ratio (OR) 4.6; 95% confidence interval (95% CI) 1.19-17.68) and sudden onset (OR 1.8; 95% CI 0.97-3.63) were predictors of cardioembolic stroke, and subacute onset (OR 8; 95% CI 1.29-49.42), COPD (OR 5.2; 95% CI 1.91-14.21), hypertension (OR 3. 63; 95% CI 1.92-6.85), hypercholesterolemia (OR 2.67; 95% CI 1.13-6. 28), transient ischaemic attack (OR 2.49; 95% CI 1.05-5.90), ischaemic heart disease (OR 2.30; 95% CI 1.15-4.60) and diabetes (OR 2.26; 95% CI 1.14-4.47) of atherothrombotic stroke. In conclusion, some clinical features at stroke onset may help clinicians to differentiate cerebral infarction subtypes in patients with atrial fibrillation. Atrial fibrillation is associated with a higher in-hospital mortality both in cardioembolic and atherothrombotic stroke patients.

Atrial fibrillation and thromboembolism: a decade of progress in stroke prevention

Atrial fibrillation is associated with a sixfold increased risk for stroke. More than a dozen published randomized trials of anticoagulants or antiplatelet agents for stroke prevention provide solid evidence on which to base antithrombotic prophylaxis. Adjusted-dose warfarin reduces risk for stroke by about 60% compared with placebo, aspirin reduces this risk (primarily for nondisabling stroke) by about 20% compared with placebo, and warfarin reduces it by about 40% compared with aspirin. Warfarin provides maximal protection against stroke at international normalized ratios of 2.0 to 3.0. Risk stratification of patients with atrial fibrillation identifies those who potentially benefit most or least from anticoagulation; this is important because a substantial percentage of patients with atrial fibrillation have relatively low rates of stroke if they are given aspirin. Many elderly patients with recurrent intermittent atrial fibrillation experience high rates of stroke and benefit from anticoagulation. The value of precordial or transesophageal echocardiography in addition to clinical risk stratifiers for stratifying stroke risk is controversial. Altered hemostasis favoring thrombosis may contribute to formation of atrial appendage thrombus, but these conditions remain ill defined. The past decade has brought unprecedented progress toward understanding thromboembolism in patients with atrial fibrillation and has changed the clinical perspective of a prevalent cardiac arrhythmia into an important opportunity for stroke prevention. Making the most of this promise calls for appreciation of the epidemiology of atrial fibrillation and the concept of risk specificity in the face of diverse therapeutic options.

Primary prevention of arterial thromboembolism in nonrheumatic atrial fibrillation: the PATAF trial study design

Patients with nonrheumatic atrial fibrillation (NRAF) have a higher risk of thromboembolism than patients in sinus rhythm. Several trials have been conducted to establish the best preventive regimen in patients with NRAF, but not in the primary-care setting. The Primary Prevention of Arterial Thromboembolism in Nonrheumatic Atrial Fibrillation (PATAF) study, a primary-care-based trial, was set up to compare the preventive efficacy of low-intensity anticoagulation (AC), target range International Normalized Ratio (INR) 1.1 < INR < 1.6 and regular-intensity AC (2.5 < INR < 3.5) therapies with that of aspirin 150 mg/d for the occurrence of thromboembolism in NRAF patients. Patients eligible for regular-intensity AC were randomly assigned to aspirin at 150 mg/d, low-intensity AC, or regular AC in group I. In cases of noneligibility for regular AC, the trial randomized patients between aspirin and low-intensity AC (assigned to group II). Primary outcome events were stroke (including intracranial hemorrhage), systemic embolism, major hemorrhage, or vascular death. Analysis of the data was based on Cox regression to compute the hazard ratio (HR) with a 95% confidence interval, using the likelihood ratio test. The trial randomized 729 patients. Patient enrollment and follow-up has been stopped, and the final analysis is now complete. We shall publish the main results as soon as possible.

Computer analysis of ultrasonic plaque echolucency in identifying high risk carotid bifurcation lesions

OBJECTIVES

to confirm that plaque echogenicity evaluated by computer analysis, as suggested by preliminary studies, can identify plaques associated with a high incidence of strokes.

MATERIALS AND METHODS

a series of 96 patients with carotid stenosis in the range of 50-99% were studied retrospectively (41 with TIAs and 55 asymptomatic). Carotid plaque echogenicity was evaluated using a computerised measurement of the median grey scale value (GSM). All patients had a CT brain scan to determine the presence of infarction in the carotid territory.

RESULTS

the incidence of ipsilateral brain CT infarctions was 16% in the asymptomatic and 32% in the symptomatic plaques (p =0.076). It was 20% for <70% stenosis and 25% for >70% stenosis (p =0.52). It was 9% for plaques which had a GSM >50 and 40% in those with GSM <50 (p <0.001) with a relative risk of 4.6 (95% CI 1.8 to 11.6).

CONCLUSIONS

the results confirm that computer analysis of plaque echogenicity is better than the degree of stenosis in identifying plaques associated with an increased incidence of CT brain-scan infarction and consequently useful for identifying individuals at high risk of stroke. What is required is a form of image standardisation in order to apply this method to natural history studies with stroke as the endpoint.

Aging and cerebrovascular disease

Aging influences cerebrovascular disease expression by a variety of mechanisms. Age-related changes in cerebral autoregulation, cellular metabolism, the blood-brain barrier, and autonomic function may leave the cerebrovascular system vulnerable to injury. Certain cerebrovascular disease, such as atrial fibrillation, watershed infarctions, carotid artery atherosclerosis, cerebral hemorrhages, subdural hematomas, and transient global amnesia manifest in the elderly. Vascular dementia and white matter disease are better understood with newer neuroimaging studies, careful neuropsychological and histopathologic examinations. Atherosclerosis and cerebral amyloid angiopathy may have larger roles than previously understood in Alzheimer's disease.

The risk of hospitalization for ischemic stroke among older adults

OBJECTIVES

The purpose of this study was to identify risk factors for stroke and to estimate their relative importance in a large, nationally representative sample of very old men and women.

METHODS

The study was designed as a secondary analysis of the Longitudinal Study on Aging. Baseline (1984) in-person interview data were linked to Medicare hospitalization records for 1984 to 1991. Participants were 6,071 noninstitutionalized adults 70 years old or older at baseline. Hospitalization for ischemic stroke was defined as having one or more episodes with a primary discharge diagnosis containing ICD-9-CM codes of 433.0-434.9, 436, and 437.0-437.1. Multivariable proportional hazards regression was used to estimate the risks associated with previously identified epidemiologic factors.

RESULTS

Five hundred and three persons (8.3%) had at least one primary discharge diagnosis of ischemic stroke. In descending order of importance-based on the partial r statistics associated with their adjusted hazards ratios (AHRs), the salient risk factors were having a previous history of stroke (AHR = 2.86), age (AHR = 1.04 per year), diabetes (AHR = 1.78), male gender (AHR = 1.42), lower body limitations (AHR = 1.09 per limitation), arthritis (AHR = 0.74), hypertension (AHR = 1.29), and poverty (AHR = 1.33).

CONCLUSION

Patients presenting with the high risk factors identified in this study should be considered for further evaluation and monitoring. Current protocols for the therapeutic management of these higher risk patients should be considered, and compliance should be encouraged.

Cardioembolic infarction in the Sagrat Cor-Alianza Hospital of Barcelona Stroke Registry

OBJECTIVES

To describe the clinical features of cardioembolic infarcts.

MATERIAL & METHODS

Cardioembolic infarct was diagnosed in 231 (15.4%) of 1500 consecutive stroke patients included in a prospective stroke registry over an 8-year period.

RESULTS

Cardiac sources of emboli included isolated atrial dysrhythmia (57.1%), valvular heart disease (20.3%), and coronary artery disease (18.2%). Patients with cardioembolic stroke showed a significantly higher (P < 0.00001) frequency of sudden onset of neurological deficit (79.7%) and altered consciousness (31.2%) than patients with lacunar infarct (38% and 1.9%) and atherothrombotic infarction (46% and 24%). Eleven patients had a spectacular shrinking deficit and 6 a presumed cardioembolic lacunar infarct. Early recurrent embolisms occurred in 6.5% of patients mostly (60%) within 7 days of initial embolism. In-hospital mortality was 27.3% (0.8% in lacunar infarcts, 21.7% in atherothrombotic infarction, P < 0.00001).

CONCLUSION

Cardioembolic infarction is a severe subtype of stroke with a high risk of early death. Clinical features at stroke onset may help clinicians to differentiate cerebral infarction subtypes and to establish prognosis more accurately.