Stroke Prevention With Left Atrial Appendage Closure in Patients With Atrial Fibrillation and Prior Intracranial Hemorrhage.

Background: Oral anticoagulation (OAC) is deemed a relative contraindication after intracranial hemorrhage (ICH) if the cause cannot be eliminated and the risk of recurrence is high. That leaves atrial fibrillation (AF) patients at high risk of thromboembolic events. Endovascular left atrial appendage closure (LAAC) can be an alternative to OAC for patients requiring stroke prevention. Methods: We performed a retrospective single-centre analysis of 138 consecutive ICH patients with nonvalvular AF and high stroke risk who underwent LAAC between 2010 and 2022 at Vancouver General Hospital. We report the baseline characteristics, procedural results, and follow-up data, comparing the observed stroke/transient ischemic attack (TIA) rate with the predicted event rate based on their CHA2DS2-VASc scores. Results: The average age was 76.1 ± 8.5 years; the mean CHA2DS2-VASc score was 4.4 ± 1.5; and the mean HAS-BLED score was 3.7 ± 0.9. The procedural success rate was 98.6%, and the complication rate was 3.6% with no periprocedural death, stroke, or TIA. The antithrombotic regimen post-LAAC consisted of short-term dual antiplatelet therapy (1-6 months) followed by aspirin alone for a minimum of 6 months in 86.2%. At mean follow-up of 14.7 ± 13.7 months, 9 deaths (6.5%, 7 cardiovascular, 2 noncardiovascular), 2 strokes (1.4%), and 1 TIA (0.7%) had occurred. The annualized observed stroke/TIA rate was 1.8%, which was lower than the adjusted predicted stroke rate of 7.0% (95% confidence interval: 4.8%-9.2%). Two patients (1.5%) suffered another ICH (both on aspirin monotherapy). One device-related thrombus (0.7%) was confirmed and treated with OAC without sequelae. Conclusion: Endovascular LAAC is a feasible alternative to OAC for stroke prevention in patients with nonvalvular AF and prior ICH.

Contexte: L'anticoagulation par voie orale (ACO) est considérée comme une contre-indication relative après une hémorragie intracrânienne (HIC) si la cause ne peut être éliminée et si le risque de récidive est élevé. Les patients souffrant de fibrillation auriculaire (FA) sont donc exposés à un risque élevé d'événements thromboemboliques. La technique de fermeture percutanée de l'appendice auriculaire gauche (AAG) peut être une solution de rechange aux anticoagulants oraux en prévention des accidents vasculaires cérébraux (AVC). Méthodologie: Nous avons réalisé une analyse rétrospective unicentrique auprès de 138 patients consécutifs qui étaient atteints d'une HIC accompagnée d'une FA non valvulaire ainsi que d'un risque élevé d'AVC et qui ont subi une fermeture de l'AAG entre 2010 et 2022 à l'hôpital général de Vancouver. Nous présentons ici les caractéristiques initiales, les résultats de l'intervention et les données de suivi, en comparant le taux d'AVC/AIT (accident ischémique transitoire) observé avec le taux prédit d'événements sur la base de leurs scores CHA2DS2-VASc. Résultats: L'âge moyen était de 76,1 ± 8,5 ans. Le score CHA2DS2-VASc moyen était de 4,4 ± 1,5, et le score HAS-BLED moyen de 3,7 ± 0,9. Le taux de réussite de l'intervention a été de 98,6 % et le taux de complications de 3,6 %, sans décès périopératoires, ni AVC ou AIT. Le traitement antithrombotique après la fermeture de l'AAG consistait en une bithérapie antiplaquettaire de courte durée (de 1 à 6 mois), suivie de la prise d'aspirine seule pendant au moins 6 mois dans 86,2 % des cas. Après un suivi moyen de 14,7 ± 13,7 mois, 9 décès (6,5 %, 7 d'origine cardiovasculaire et 2 d'origine non cardiovasculaire), 2 AVC (1,4 %) et 1 AIT (0,7 %) sont survenus. Le taux annualisé d'AVC/AIT observé était de 1,8 %, ce qui est inférieur au taux prédit d'AVC après ajustement, soit 7,0 % (intervalle de confiance à 95 % : 4,8 % à 9,2 %). Deux patients (1,5 %) ont souffert d'une autre HIC (tous deux sous aspirine en monothérapie). Un thrombus lié au dispositif (0,7 %) a été confirmé et traité par anticoagulathérapie orale sans séquelles. Conclusion: La technique de fermeture de l'AAG représente une solution de rechange à l'anticoagulation par voie orale dans la prévention des AVC chez les patients souffrant de FA non valvulaire et ayant déjà subi une HIC.

Ninety-Day Stroke or Transient Ischemic Attack Recurrence in Patients Prescribed Anticoagulation in the Emergency Department With Atrial Fibrillation and a New Transient Ischemic Attack or Minor Stroke.

Background For patients with atrial fibrillation seen in the emergency department (ED) following a transient ischemic attack (TIA) or minor stroke, the impact of initiating oral anticoagulation immediately rather than deferring the decision to outpatient follow-up is unknown. Methods and Results We conducted a planned secondary data analysis of a prospective cohort of 11 507 adults in 13 Canadian EDs between 2006 and 2018. Patients were eligible if they were aged 18 years or older, with a final diagnosis of TIA or minor stroke with previously documented or newly diagnosed atrial fibrillation. The primary outcome was subsequent stroke, recurrent TIA, or all-cause mortality within 90 days of the index TIA diagnosis. Secondary outcomes included stroke, recurrent TIA, or death and rates of major bleeding. Of 11 507 subjects with TIA/minor stroke, atrial fibrillation was identified in 11.2% (1286, mean age, 77.3 [SD 11.1] years, 52.4% male). Over half (699; 54.4%) were already taking anticoagulation, 89 (6.9%) were newly prescribed anticoagulation in the ED. By 90 days, 4.0% of the atrial fibrillation cohort had experienced a subsequent stroke, 6.5% subsequent TIA, and 2.6% died. Results of a multivariable logistic regression indicate no association between prescribed anticoagulation in the ED and these 90-day outcomes (composite odds ratio, 1.37 [95% CI, 0.74-2.52]). Major bleeding was found in 5 patients, none of whom were in the ED-initiated anticoagulation group. Conclusions Initiating oral anticoagulation in the ED following new TIA was not associated with lower recurrence rates of neurovascular events or all-cause mortality in patients with atrial fibrillation.

Prospective Validation of Computed Tomography to Identify Patients at High Risk for Stroke After Transient Ischemic Attack or Minor Stroke.

BACKGROUND: Computed tomography (CT) findings of acute and chronic ischemia are associated with subsequent stroke risk in patients with transient ischemic attack. We sought to validate these associations in a large prospective cohort of patients with transient ischemic attack or minor stroke. METHODS: This prospective cohort study enrolled emergency department patients from 13 hospitals with transient ischemic attack who had CT imaging. Primary outcome was stroke within 90 days. Secondary outcomes were stroke within 2 or 7 days. CT findings were abstracted from radiology reports and classified for the presence of acute ischemia, chronic ischemia, or microangiopathy. Multivariable logistic regression was used to test associations with primary and secondary end points. RESULTS: From 8670 prospectively enrolled patients between May 2010 and May 2017, 8382 had a CT within 24 hours. From this total population, 4547 (54%) patients had evidence of acute ischemia, chronic ischemia, or microangiopathy on CT, of whom 175 had a subsequent stroke within 90 days (3.8% subsequent stroke rate; adjusted odds ratio [aOR], 2.33 [95% CI, 1.62-3.36]). This was in comparison to those with CT imaging without ischemia. Findings associated with an increased risk of stroke at 90 days were isolated acute ischemia (6.0%; aOR, 2.42 [95% CI, 1.03-5.66]), acute ischemia with microangiopathy (10.7%; aOR, 3.34 [95% CI, 1.57-7.14]), chronic ischemia with microangiopathy (5.2%; aOR, 1.83 [95% CI, 1.34-2.50]), and acute ischemia with chronic ischemia and microangiopathy (10.9%; aOR, 3.49 [95% CI, 1.54-7.91]). Acute ischemia with chronic ischemia and microangiopathy were most strongly associated with subsequent stroke within 2 days (aOR, 4.36 [95% CI, 1.31-14.54]) and 7 days (aOR, 4.50 [95% CI, 1.73-11.69]). CONCLUSIONS: In patients with transient ischemic attack or minor stroke, CT evidence of acute ischemia with chronic ischemia or microangiopathy significantly increases the risk of subsequent stroke within 90 days of index visit. The combination of all 3 findings results in the greatest early risk.

Risk of stroke is low after transient ischemic attack presentation with isolated dizziness.

OBJECTIVE: Stroke presenting as dizziness is a diagnostic challenge in frontline settings, given the multitude of benign conditions that present similarly. The risk of stroke after episodic dizziness is unknown, leading to divergent guidance on optimal workup and management. Prior TIA risk scores have shown a history of dizziness is a negative predictor of subsequent stroke. Our objective was to assess the subsequent stroke risk within 90 days following emergency department assessment (ED) for isolated dizziness diagnosed as TIA during the index visit. METHODS: We conducted prospective, multicenter cohort studies at 13 Canadian EDs over 11 years. We enrolled patients diagnosed with TIA and compared patients with isolated dizziness to those with other neurological deficits. Our primary outcome was subsequent stroke within 90 days. Secondary outcomes were subsequent stroke within 2, 7, and 30 days, respectively, as well as subsequent TIA within 90 days. RESULTS: Only 4/483 (0.8%) patients with isolated dizziness had a stroke within 90 days compared to 320/11024 (2.9%) of those with any focal neurological sign or symptom (RR 0.29, 95% CI 0.11-0.76). Over the first 90 days, the two groups differ significantly in their probability of stroke (p = 0.007). Subsequent TIA was also significantly less common in the isolated dizziness group (1.7% vs. 5.6%, p = 0.001) with a relative risk of 0.30 (95% CI 0.15-0.60). CONCLUSION: The risk of subsequent stroke following ED presentation for TIA is low when the presenting symptoms are isolated dizziness.

RéSUMé: OBJECTIF: Les accidents vasculaires cérébraux (AVC) se présentant sous forme de vertiges constituent un défi diagnostique en première ligne, étant donné la multitude d'affections bénignes qui se présentent de la même manière. Le risque d'accident vasculaire cérébral (AVC) après des vertiges épisodiques est inconnu, ce qui donne lieu à des conseils divergents sur le bilan et la prise en charge optimaux. Des scores de risque d'AIT antérieurs ont montré que des antécédents de vertiges sont un facteur prédictif négatif d'accident vasculaire cérébral ultérieur. Notre objectif était d'évaluer le risque ultérieur d'accident vasculaire cérébral (AVC) dans les 90 jours suivant l'évaluation aux urgences d'un étourdissement isolé diagnostiqué comme un AIT lors de la visite de référence. MéTHODES: Nous avons mené des études de cohorte prospectives multicentriques dans 13 services d'urgence canadiens pendant 11 ans. Nous avons recruté des patients ayant reçu un diagnostic d'AIT et avons comparé les patients présentant des vertiges isolés à ceux présentant d'autres déficits neurologiques. Nous avons inscrit des patients ayant reçu un diagnostic d'AIT et comparé des patients ayant des étourdissements isolés à ceux présentant d'autres déficits neurologiques. Notre résultat primaire était l'AVC subséquent dans les 90 jours. Les résultats secondaires étaient l'AVC subséquent dans les 2, 7 et 30 jours, respectivement, ainsi que l'AIT subséquent dans les 90 jours. RéSULTATS: Seuls 4/483 (0,8 %) des patients présentant des vertiges isolés ont eu un AVC dans les 90 jours, contre 320/11 024 (2,9 %) de ceux présentant un signe ou symptôme neurologique focal (RR 0,29, IC 95 % 0,11-0,76). Au cours des 90 premiers jours, les deux groupes diffèrent significativement en termes de probabilité d'AVC (p = 0,007). L'AIT ultérieur était également significativement moins fréquent dans le groupe des vertiges isolés (1,7 % contre 5,6 %, p = 0,001) avec un risque relatif de 0,30 (IC 95 % 0,15-0,60). CONCLUSIONS: Le risque d'AVC ultérieur après une présentation aux urgences pour un AIT est faible lorsque les symptômes présentés sont des étourdissements isolés.

Predictors of neurologists confirming or overturning emergency physicians' diagnosis of TIA or stroke.

BACKGROUND: Transient ischemic attack (TIA) and non-disabling stroke are common emergency department (ED) presentations. Currently, there are no prospective multicenter studies determining predictors of neurologists confirming a diagnosis of cerebral ischemia in patients discharged with a diagnosis of TIA or stroke. The objectives were to (1) calculate the concordance between emergency physicians and neurologists for the outcome of diagnosing TIA or stroke, and (2) identify characteristics associated with neurologists diagnosing a stroke mimic. METHODS: This was a planned sub-study of a prospective cohort study at 14 Canadian EDs enrolling patients diagnosed with TIA or non-disabling stroke from 2006 to 2017. Logistic regression was used to identify factors associated with neurologists' diagnosis of cerebral ischemia. Our primary outcome was the composite outcome of cerebral ischemia (TIA or non-disabling stroke) based on the neurologists' assessment. RESULTS: The diagnosis of cerebral ischemia was confirmed by neurologists in 5794 patients (55.4%). The most common identified stroke mimics were migraine (18%), peripheral vertigo (7%), syncope (4%), and seizure (3%). Over a third of patients (38.4%) ultimately had an undetermined aetiology for their symptoms. The strongest predictors of cerebral ischemia confirmation were infarct on CT (OR 1.83, 95% CI 1.65-2.02), advanced age (OR comparing 75th-25th percentiles 1.67, 1.55-1.80), language disturbance (OR 1.92, 1.75-2.10), and smoking (OR 1.67, 1.46-1.91). The strongest predictors of stroke mimics were syncope (OR 0.59, 0.48-0.72), vertigo (OR 0.52, 0.45-0.59), bilateral symptoms (OR 0.60, 0.50-0.72), and confusion (OR 0.50, 0.44-0.57). CONCLUSION: Physicians should have a high index of suspicion of cerebral ischemia in patients with advanced age, smoking history, language disturbance, or infarcts on CT. Physicians should discriminate in which patients to pursue stroke investigations on when deemed at minimal risk of cerebral ischemia, including those with isolated vertigo, syncope, or bilateral symptoms.

RéSUMé: CONTEXTE: L'accident ischémique transitoire (AIT) et l'accident vasculaire cérébral (AVC) non invalidant sont des présentations courantes dans les services d'urgence. Actuellement, il n'existe pas d'études prospectives multicentriques déterminant les facteurs prédictifs de la confirmation par les neurologues d'un diagnostic d'ischémie cérébrale chez les patients sortis de l'hôpital avec un diagnostic d'AIT ou d'AVC. Les objectifs étaient de (1) calculer la concordance entre les urgentistes et les neurologues pour le résultat du diagnostic de l'AIT ou de l'AVC, et (2) identifier les caractéristiques associées au diagnostic par les neurologues d'une imitation d'AVC. MéTHODES: Il s'agissait d'une sous-étude planifiée d'une étude de cohorte prospective dans 14 services d'urgence canadiens recrutant des patients diagnostiqués avec un AIT ou un AVC non invalidant de 2006 à 2017. Une régression logistique a été utilisée pour identifier les facteurs associés au diagnostic d'ischémie cérébrale par les neurologues. Notre résultat principal était le résultat composite de l'ischémie cérébrale (AIT ou accident vasculaire cérébral non invalidant) selon l'évaluation des neurologues. RéSULTATS: Le diagnostic d'ischémie cérébrale a été confirmé par des neurologues chez 5 794 patients (55,4 %). Les imitateurs d'AVC identifiés les plus courants étaient la migraine (18 %), le vertige périphérique (7 %), la syncope (4 %) et les convulsions (3 %). Plus d'un tiers des patients (38,4 %) avaient finalement une étiologie indéterminée pour leurs symptômes. Les prédicteurs les plus forts de la confirmation de l'ischémie cérébrale étaient l'infarctus au scanner (OR 1.83, IC 95 % 1.65­2.02), l'âge avancé (OR comparant les 75e et 25e percentiles 1.67, 1.55­1.80), les troubles du langage (OR 1.92, 1.75­2.10) et le tabagisme (OR 1.67, 1.46­1.91). Les prédicteurs les plus forts d'imitateurs d'AVC étaient la syncope (OR 0.59, 0.48­0.72), le vertige (OR 0.52, 0.45­0.59), les symptômes bilatéraux (OR 0.60, 0.50­0.72) et la confusion (OR 0.50, 0.44­0.57). CONCLUSION: Les médecins devraient avoir un indice élevé de suspicion d'ischémie cérébrale chez les patients ayant un âge avancé, des antécédents de tabagisme, des troubles du langage ou des infarctus au scanner. Les médecins doivent distinguer les patients sur lesquels poursuivre des investigations sur un AVC lorsqu'ils sont jugés à risque minimal d'ischémie cérébrale, y compris ceux présentant des vertiges isolés, une syncope ou des symptômes bilatéraux.

Prospective validation of Canadian TIA Score and comparison with ABCD2 and ABCD2i for subsequent stroke risk after transient ischaemic attack: multicentre prospective cohort study.

OBJECTIVE: To validate the previously derived Canadian TIA Score to stratify subsequent stroke risk in a new cohort of emergency department patients with transient ischaemic attack. DESIGN: Prospective cohort study. SETTING: 13 Canadian emergency departments over five years. PARTICIPANTS: 7607 consecutively enrolled adult patients attending the emergency department with transient ischaemic attack or minor stroke. MAIN OUTCOME MEASURES: The primary outcome was subsequent stroke or carotid endarterectomy/carotid artery stenting within seven days. The secondary outcome was subsequent stroke within seven days (with or without carotid endarterectomy/carotid artery stenting). Telephone follow-up used the validated Questionnaire for Verifying Stroke Free Status at seven and 90 days. All outcomes were adjudicated by panels of three stroke experts, blinded to the index emergency department visit. RESULTS: Of the 7607 patients, 108 (1.4%) had a subsequent stroke within seven days, 83 (1.1%) had carotid endarterectomy/carotid artery stenting within seven days, and nine had both. The Canadian TIA Score stratified the risk of stroke, carotid endarterectomy/carotid artery stenting, or both within seven days as low (risk ≤0.5%; interval likelihood ratio 0.20, 95% confidence interval 0.09 to 0.44), medium (risk 2.3%; interval likelihood ratio 0.94, 0.85 to 1.04), and high (risk 5.9% interval likelihood ratio 2.56, 2.02 to 3.25) more accurately (area under the curve 0.70, 95% confidence interval 0.66 to 0.73) than did the ABCD2 (0.60, 0.55 to 0.64) or ABCD2i (0.64, 0.59 to 0.68). Results were similar for subsequent stroke regardless of carotid endarterectomy/carotid artery stenting within seven days. CONCLUSION: The Canadian TIA Score stratifies patients' seven day risk for stroke, with or without carotid endarterectomy/carotid artery stenting, and is now ready for clinical use. Incorporating this validated risk estimate into management plans should improve early decision making at the index emergency visit regarding benefits of hospital admission, timing of investigations, and prioritisation of specialist referral.

Rapidly expanding venous intracerebral haemorrhage with spot sign.

A 79-year-old woman was brought to the hospital with an acute-onset left haemiparesis. On initial examination, she had a pure sensorimotor syndrome with left-sided weakness and sensory disturbance. Her mental status was normal. She had normal visual fields to confrontation and no neglect. Her initial CT and CT angiogram revealed cerebral venous thrombosis with associated haemorrhage. A 'spot sign' was visible on CT angiogram. Immediately following the CT scan, the patient had a rapidly progressive decline in level of consciousness, requiring endotracheal intubation. A follow-up CT scan 70 min later showed the haemorrhage had expanded dramatically, with mass effect, midline shift and herniation. After a discussion with the family, the patient was extubated and died the following day. This is the first case of a cerebral venous thrombosis with associated spot sign-positive haemorrhage and published clinical details that the authors are aware of.

Stroke Education in Canadian Emergency Medicine Residency Programs.

OBJECTIVES: Stroke and transient ischemic attack (TIA) are common disorders treated by Canadian emergency physicians. The diagnosis and management of these conditions is time-sensitive and complex, requiring that emergency physicians have adequate training. This study sought to determine the extent of stroke and TIA training in Canadian emergency medicine residency programs. METHODS: A two-page survey was emailed to directors of all English-speaking emergency medicine residency programs in Canada. This included both the Fellow of the Royal College of Physicians of Canada (FRCPC) and the College of Family Physicians Enhanced Training [CCFP(EM)] residency programs. The number of mandatory and elective rotations, lectures, and examinations relevant to stroke and TIA were assessed. RESULTS: Nine FRCPC programs responded (of 11; RR=82%) and 11 CCFP(EM) programs responded (of 18; RR=61%), representing 20 of 29 programs in Canada (RR: 20/29=69%). Mandatory general neurology (3/9) and stroke neurology (2/9) rotations were offered in a minority of FRCPC programs and not at all in CCFP(EM) programs (0/11). Neuroradiology rotations were mandatory in 1/9 FRCPC programs and no CCFP(EM) programs (0/11). Acute ischemic stroke was allocated 3 hours of lecture time per year in all residency programs, regardless of route of training. Despite the fact that 100% of respondents train residents in facilities that administer thrombolysis for stroke, only 1/11 (9%) CCFP(EM) programs and 0/9 FRCPC programs have residents act as stroke team leaders. CONCLUSIONS: Formal training in stroke and TIA is limited in Canadian emergency medicine residency programs. Enhanced training opportunities should be developed as this disease is sudden, life-threatening, and can have disabling or fatal consequences, and therapeutic options are time sensitive.

Aligning health care policy with evidence-based medicine: the case for funding direct oral anticoagulants in atrial fibrillation.

Misalignment between evidence-informed clinical care guideline recommendations and reimbursement policy has created care gaps that lead to suboptimal outcomes for patients denied access to guideline-based therapies. The purpose of this article is to make the case for addressing this growing access barrier to optimal care. Stroke prevention in atrial fibrillation (AF) is discussed as an example. Stroke is an extremely costly disease, imposing a significant human, societal, and economic burden. Stroke in the setting of AF carries an 80% probability of death or disability. Although two-thirds of these strokes are preventable with appropriate anticoagulation, this has historically been underprescribed and poorly managed. National and international guidelines endorse the direct oral anticoagulants as first-line therapy for this indication. However, no Canadian province has provided these agents with an unrestricted listing. These decisions appear to be founded on silo-based cost assessment-the drug costs rather than the total system costs-and thus overlook several important cost-drivers in stroke. The discordance between best scientific evidence and public policy requires health care providers to use a potentially suboptimal therapy in contravention of guideline recommendations. It represents a significant obstacle for knowledge translation efforts that aim to increase the appropriate anticoagulation of Canadians with AF. As health care professionals, we have a responsibility to our patients to engage with policy-makers in addressing and resolving this barrier to optimal patient care.

Larger A1/M1 diameter ratio predicts embolic anterior cerebral artery territorial stroke.

BACKGROUND AND PURPOSE: In contrast to middle cerebral artery territory strokes, anterior cerebral artery strokes (ACAS) occur rarely. The low frequency of ACAS, in relation to middle cerebral artery territory strokes, may be explained by differences in ACA and middle cerebral artery anatomy influencing their respective flow-directed embolism rates. We aimed to determine whether variability in ACA anatomy, and in particular A1 segment diameter, is associated with embolic ACAS. METHODS: Consecutive patients admitted to Boston Medical Center with embolic ACAS were reviewed. Ipsilateral and contralateral A1 diameters, M1 diameters, and terminal internal carotid artery bifurcation angles were measured from computed tomographic angiography and MRI angiography images. We compared these measurements between cases of ACAS and consecutive cases of embolic middle cerebral artery territory strokes. RESULTS: The study comprised 55 individuals (27 ACAS, 28 middle cerebral artery territory strokes) with mean age of 69 years. In multivariate regression analysis, larger ipsilateral A1 diameters (odds ratio per 1 mm increment: 8.5; 95% confidence interval, 1.4-53.3) and ipsilateral A1/M1 diameter ratio (odds ratio per 10% increment: 1.8; 95% confidence interval, 1.2-2.9) were associated with ACAS, whereas larger ipsilateral M1 diameters was protective for ACAS (odds ratio per 1 mm increment: 0.8; 95% confidence interval, 0.0-0.9). CONCLUSIONS: Larger ipsilateral A1 diameters and A1/M1 diameter ratio are associated with embolic ACAS. These findings suggest that A1 diameters and M1 diameters are important in determining the path of emboli that reach the terminal internal carotid artery.

The use of antiplatelet therapy in the outpatient setting: Canadian Cardiovascular Society guidelines.

Antiplatelet agents are a cornerstone of therapy for patients with atherosclerotic vascular disease. There is presently a lack of comprehensive guidelines focusing on the use of antiplatelet drugs in patients currently manifesting or at elevated risk of cardiovascular disease. The Canadian Antiplatelet Therapy Guidelines Committee reviewed existing disease-based guidelines and subsequently published literature and used expert opinion and review to develop guidelines on the use of antiplatelet therapy in the outpatient setting. This full document has been summarized in an Executive Summary published in the Canadian Journal of Cardiology and may be found at http://www.ccs.ca/. Antiplatelet therapy appears to be generally underused, perhaps in part because of a lack of clear, evidence-based guidance. Here, we provide specific guidelines for secondary prevention in patients discharged from hospital following acute coronary syndromes, post-percutaneous coronary intervention, post-coronary artery bypass grafting, patients with a history of transient cerebral ischemic events or strokes, and patients with peripheral arterial disease. Issues related to primary prevention are also addressed, in addition to special clinical contexts such as diabetes, heart failure, chronic kidney disease, pregnancy/lactation, and perioperative management. Recommendations are provided regarding pharmacologic interactions that may occur during combination therapy with warfarin, clopidogrel and proton-pump inhibitors, or acetylsalicylic acid and nonsteroidal anti-inflammatory drugs, as well as for the management of bleeding complications.

The use of antiplatelet therapy in the outpatient setting: Canadian Cardiovascular Society Guidelines Executive Summary.

Antiplatelet agents are a cornerstone of therapy for patients with atherosclerotic vascular disease. There is presently a lack of comprehensive guidelines focusing on the use of antiplatelet drugs in patients currently manifesting or at elevated risk of cardiovascular disease. The Canadian Antiplatelet Therapy Guidelines Committee reviewed existing disease-based guidelines and subsequently published literature and used expert opinion and review to develop guidelines on the use of antiplatelet therapy in the outpatient setting. This Executive Summary provides an abbreviated version of the principal recommendations. Antiplatelet therapy appears to be generally underused, perhaps in part because of a lack of clear, evidence-based guidance. Here, we provide specific guidelines for secondary prevention in patients discharged from hospital after acute coronary syndromes, percutaneous coronary intervention, or coronary artery bypass grafting; patients with a history of transient cerebral ischemic events or strokes; and patients with peripheral arterial disease. Issues related to primary prevention are also addressed, in addition to special clinical contexts such as diabetes, heart failure, chronic kidney disease, pregnancy or lactation, and perioperative management. Recommendations are provided regarding pharmacologic interactions that may occur during combination therapy with warfarin, clopidogrel, and proton-pump inhibitors, or aspirin and nonsteroidal anti-inflammatory drugs, as well as for the management of bleeding complications. The complete guidelines document is published as a supplementary issue of the Canadian Journal of Cardiology and is available at http://www.ccs.ca/.

Changes in intracortical excitability after transient ischemic attack are associated with ABCD² score.

BACKGROUND AND PURPOSE: A transient ischemic attack (TIA) is a brief ischemic episode characterized by rapid clinical resolution and not associated with permanent cerebral infarction. Whether changes in intracortical excitability persist and are related to clinical predictors of stroke risk after TIA remains unknown. METHODS: Participants were individuals with clinically resolved motor TIA with no structural lesions and healthy age-matched control participants. Single and paired-pulse transcranial magnetic stimulation was used to measure intracortical excitability. Recruitment curves for percent inhibition and facilitation were used to derive excitability thresholds. Correlations between threshold asymmetries and ABCD(2) score were performed. RESULTS: Results showed a significant 3-way interaction with reduced inhibition and enhanced facilitation in the affected compared with unaffected hemisphere after TIA. No significant differences were present in healthy participants. Asymmetries in intracortical inhibition and facilitation were significantly correlated with ABCD(2) score. CONCLUSIONS: The present study is the first, to our knowledge, to demonstrate altered intracortical inhibition and facilitation in the affected hemisphere after TIA. These changes occurred on average 2 weeks after clinical signs of TIA resolved and in the absence of structural lesions and were not present in healthy age-matched control participants. Furthermore, this study is the first, to our knowledge, to report that changes in intracortical excitability after TIA are associated with ABCD(2) score.

Delayed detection of atrial fibrillation after ischemic stroke.

BACKGROUND: Detection of atrial fibrillation (AF) after ischemic stroke is important because anticoagulation is indicated to reduce the risk of recurrent stroke. However, no consensus exists about the optimum method for detecting underlying paroxysmal AF not apparent on presentation with stroke. The aim of this study was to characterize the rate, timing, and predictors of delayed detection of AF after stroke. METHODS: The Virtual International Stroke Trials Archive provided data from 3464 patients in the placebo arms of 4 clinical trials of therapies for acute ischemic stroke. Patients who had AF by history or on the baseline electrocardiogram were excluded. Electrocardiograms were obtained routinely and as clinically indicated. The time to detection of AF was evaluated using Kaplan-Meier survival statistics. Cox proportional hazards analysis was used to evaluate risk factors for AF. RESULTS: Among 2504 qualifying patients, AF was detected in 174 (6.9%; 95% confidence interval [CI] 6.0%-8.0%). In 68% of patients, AF was detected more than 48 hours after presentation. Detection of AF was associated with increasing age (hazard ratio [HR] 1.6/decade; 95% CI 1.4-1.9; P < .005), female sex (HR 1.7; CI 1.2-2.4; P < .005), congestive heart failure (HR 1.9; CI 1.1-3.4; P = .02), and the absence of hypertension (HR 1.6; CI 1.1-2.2; P = .01). CONCLUSIONS: Delayed detection of AF was common in this large cohort of patients carefully monitored after ischemic stroke. Current methods of screening may fail to detect underlying paroxysmal AF in a substantial proportion of patients.

A randomized, double-blind, placebo-controlled trial to evaluate the efficacy, safety, tolerability, and pharmacokinetic/pharmacodynamic effects of a targeted exposure of intravenous repinotan in patients with acute ischemic stroke: modified Randomized Exposure Controlled Trial (mRECT).

BACKGROUND AND PURPOSE: Repinotan hydrochloride is a serotonin (5-HT)(1A) receptor full agonist with evidence of neuroprotection in animal models of permanent and transient focal ischemia. The purpose of this Phase IIb study was to investigate the efficacy, safety, and tolerability of a targeted exposure to repinotan in patients with acute ischemic stroke. METHODS: This was a double-blind, placebo-controlled, parallel-group, multicenter study of 681 patients stratified according to whether or not tissue plasminogen activator was administered and then randomly assigned to treatment with repinotan or placebo. A continuous 72-hour intravenous infusion of repinotan or placebo was to be started within 4.5 hours from the onset of ischemic symptoms. A Point-of-Care test was used to adjust the infusion rate if appropriate. The goal of Modified Randomized Exposure Controlled Trial (mRECT) was to show whether repinotan is statistically superior to placebo (alpha or=85) at 3 months, using a Cochran-Mantel-Haenszel test. RESULTS: For the intention-to-treat population at 3 months, the response rate on the Barthel Index was 37.1% (127 of 342) for patients on repinotan and 42.4% (143 of 337) for patients taking the placebo (Cochran-Mantel-Haenszel probability value=0.149). No apparent safety concerns were identified. CONCLUSIONS: mRECT demonstrated the feasibility of conducting a rigorous trial using a short therapeutic window demanding clinical and radiographic criteria to optimize patient selection and a Point-of-Care test to achieve a targeted exposure to repinotan. The study failed to demonstrate a clinical benefit of repinotan. The development of repinotan in acute ischemic stroke was discontinued.

Effects of aspirin plus extended-release dipyridamole versus clopidogrel and telmisartan on disability and cognitive function after recurrent stroke in patients with ischaemic stroke in the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial: a double-blind, active and placebo-controlled study.

BACKGROUND: The treatment of ischaemic stroke with neuroprotective drugs has been unsuccessful, and whether these compounds can be used to reduce disability after recurrent stroke is unknown. The putative neuroprotective effects of antiplatelet compounds and the angiotensin II receptor antagonist telmisartan were investigated in the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial. METHODS: Patients who had had an ischaemic stroke were randomly assigned in a two by two factorial design to receive either 25 mg aspirin (ASA) and 200 mg extended-release dipyridamole (ER-DP) twice a day or 75 mg clopidogrel once a day, and either 80 mg telmisartan or placebo once per day. The predefined endpoints for this substudy were disability after a recurrent stroke, assessed with the modified Rankin scale (mRS) and Barthel index at 3 months, and cognitive function, assessed with the mini-mental state examination (MMSE) score at 4 weeks after randomisation and at the penultimate visit. Analysis was by intention to treat. The study was registered with ClinicalTrials.gov, number NCT00153062. FINDINGS: 20,332 patients (mean age 66 years) were randomised and followed-up for a median of 2.4 years. Recurrent strokes occurred in 916 (9%) patients randomly assigned to ASA with ER-DP and 898 (9%) patients randomly assigned to clopidogrel; 880 (9%) patients randomly assigned to telmisartan and 934 (9%) patients given placebo had recurrent strokes. mRS scores were not statistically different in patients with recurrent stroke who were treated with ASA and ER-DP versus clopidogrel (p=0.38), or with telmisartan versus placebo (p=0.61). There was no significant difference in the proportion of patients with recurrent stroke with a good outcome, as measured with the Barthel index, across all treatment groups. Additionally, there was no significant difference in the median MMSE scores, the percentage of patients with an MMSE score of 24 points or less, the percentage of patients with a drop in MMSE score of 3 points or more between 1 month and the penultimate visit, and the number of patients with dementia among the treatment groups. There were no significant differences in the proportion of patients with cognitive impairment or dementia among the treatment groups. INTERPRETATION: Disability due to recurrent stroke and cognitive decline in patients with ischaemic stroke were not different between the two antiplatelet regimens and were not affected by the preventive use of telmisartan.

Aspirin and extended-release dipyridamole versus clopidogrel for recurrent stroke.

BACKGROUND: Recurrent stroke is a frequent, disabling event after ischemic stroke. This study compared the efficacy and safety of two antiplatelet regimens--aspirin plus extended-release dipyridamole (ASA-ERDP) versus clopidogrel. METHODS: In this double-blind, 2-by-2 factorial trial, we randomly assigned patients to receive 25 mg of aspirin plus 200 mg of extended-release dipyridamole twice daily or to receive 75 mg of clopidogrel daily. The primary outcome was first recurrence of stroke. The secondary outcome was a composite of stroke, myocardial infarction, or death from vascular causes. Sequential statistical testing of noninferiority (margin of 1.075), followed by superiority testing, was planned. RESULTS: A total of 20,332 patients were followed for a mean of 2.5 years. Recurrent stroke occurred in 916 patients (9.0%) receiving ASA-ERDP and in 898 patients (8.8%) receiving clopidogrel (hazard ratio, 1.01; 95% confidence interval [CI], 0.92 to 1.11). The secondary outcome occurred in 1333 patients (13.1%) in each group (hazard ratio for ASA-ERDP, 0.99; 95% CI, 0.92 to 1.07). There were more major hemorrhagic events among ASA-ERDP recipients (419 [4.1%]) than among clopidogrel recipients (365 [3.6%]) (hazard ratio, 1.15; 95% CI, 1.00 to 1.32), including intracranial hemorrhage (hazard ratio, 1.42; 95% CI, 1.11 to 1.83). The net risk of recurrent stroke or major hemorrhagic event was similar in the two groups (1194 ASA-ERDP recipients [11.7%], vs. 1156 clopidogrel recipients [11.4%]; hazard ratio, 1.03; 95% CI, 0.95 to 1.11). CONCLUSIONS: The trial did not meet the predefined criteria for noninferiority but showed similar rates of recurrent stroke with ASA-ERDP and with clopidogrel. There is no evidence that either of the two treatments was superior to the other in the prevention of recurrent stroke. (ClinicalTrials.gov number, NCT00153062.)