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Objective: To study the short and long term differences in outcome between patients >80 years of age and those (79 years of age who received intravenous recombinant tissue plasminogen activator (iv rt-PA) for acute stroke within the first 3 hours of symptom onset. Methods: We studied consecutive patients treated with iv rt-PA for acute stroke, with prospective follow up of up to 3 years. Outcome measures included National Institutes of Health Stroke Scale (NIHSS) score, Barthel Index (BI), modified Rankin score (MRS), and stroke mortality. Patients were split into two groups: younger ( (79 years) and older (>80 years). Results: There were 65 patients in the younger cohort and 31 patients in the older. Older patients were more likely to present with more severe baseline stroke (p = 0.04; odds ratio (OR) 3.04; 95% confidence interval (CI) 1.03 to 8.98). Stroke mortality at 90 days was 10.8% in the younger and 32.3% in the older cohort (p = 0.01). At 90 days' follow up, patients in the older cohort with more severe stroke (NIHSS score >11) were nearly 10 times more likely to have poor outcome compared with their younger counterparts presenting with severe stroke (p = 0.001; OR = 10.36; 95% CI 2.16 to 49.20). Baseline stroke severity and age were the only independent and equal predictors for stroke outcome. No threshold was found for age or baseline stroke severity predicting outcome. Conclusion: Older patients presenting with more severe baseline stroke are much less likely to benefit from iv rt-PA as compared with their younger counterparts.

Background-Power motion-mode transcranial Doppler (TCD) (PMD) is a new, multigated technique that may simplify and enhance detection of embolus. We developed criteria for emboli detection using PMD. Then, we performed a blinded comparison of transcranial PMD with single-gate spectral TCD in TCD bubble study patients. Methods-Patients with right-to-left shunt as detected with standard TCD were selected for this study. The international emboli criteria for spectral TCD were used. We defined novel PMD criteria for detecting emboli signature on PMD as follows: (1) signature at least 3 dB higher than the highest spontaneous PMD display of background blood flow; (2) embolic signature reflects motion in one direction at a minimum spatial extent of 7.5 mm and temporal extent of 30 ms; (3) embolus must traverse a prespecified depth. Each study was blindly assessed for microbubble signals (MBS) count on either modality. Results-Thirty-six patients were included in the study. Mean age was 44.4 (SD 14.4), 50% were male, and median time from stroke onset to TCD bubble test was 12 days. Median MBS count in middle cerebral arteries (MCA) was 4 on both modalities. Spectral TCD MBS counts were highly correlated (ϭ0.97) with PMD MBS counts in MCA and similarly in anterior cerebral arteries (ACA) (ϭ0.79). When PMD microbubble counts in the ACA and MCA were summed, a clear 2-fold difference emerged between 2 modalities (PϽ0.001). In younger patients (Ͻ55 years), paradoxical embolization through cardiac right-to-left shunts has been proposed as etiology for ischemic stroke and transient ischemic attack (TIA). 4 A recent transesophageal echocardiography (TEE) study showed that patient with both patent foramen ovale (PFO) and atrial septal aneurysm (ASA) are at increased risk of recurrent stroke. 5 TCD detects right-to-left shunts via the "TCD bubble study," in which microbubble signals (MBS) are identified in the intracranial arteries several seconds after venous injection of a contrast agent or agitated saline. When performed with a validated protocol, this test has a sensitivity of Ͼ90% and specificity of 70% to 75% for identifying PFO when compared with TEE. 6 When both TCD bubble studies and TEE are used in all patients suspected to have PFO, PFO detection rate is higher than when using either method alone. 7 A portable 2 MHz Power M-mode digital transcranial Doppler (TCD) system (PMD) has been recently introduced. 8 Transcranial PMD may enhance the detection of MBS during the TCD bubble study. We compared standard single-gate spectral TCD with multiple-gated PMD to detect MBS during TCD bubble studies. Conclusion-When MethodsStroke and TIA patients from 2 academic stroke centers participated in the study. All patients had positive TCD bubble studies with right-to-left shunts on spectral TCD. In both centers, a technician and an expert neurosonologist performed the procedure.Transcranial PMD (Spencer Technologies, Inc; PMD 100 mol/L) was used in all TCD bubble studies. This technology collects (1) 2-MHz spectral single-gate TCD i...

STROKE IS A MAJOR CAUSE OF MORBIDITY and mortality in an aging population. The current understanding of the pathophysiology of atherosclerotic diseases, the most common cause of stroke, and the evidence for existing therapeutic interventions for the prevention of stroke are presented. Specifically, we review the evidence for antiplatelet agents, anticoagulants, antihypertensive medications, lipidlowering agents and carotid endarterectomy for stroke prevention. primary preventive measure, antiplatelet agents do not reduce the risk of ischemic stroke among patients without vascular disease. They are associated with an increased risk of intracranial hemorrhage (odds ratio [OR] 1.35, 95% confidence interval [CI] 0.88-2.10) 23 and major noncerebral hemorrhage (OR 1.73, 95% CI 1.14-2.63 ). 24 The benefits of ASA in the secondary prevention of stroke have been well documented in the period immediately after a stroke 25 (Table 1). Long-term antiplatelet treatment after stroke shows an even more impressive reduction of 25 nonfatal strokes and 36 serious vascular events per 1000 treated over a 29-month follow-up period. 25 There appears to be no difference in efficacy between low (50 mg) and higher doses (up to 1500 mg) of ASA. 29,30 The combination of dipyridamole and ASA has been shown to reduce the relative risk of recurrent stroke compared with ASA alone 26 (Table 1). Dipyridamole inhibits platelet aggregation by increasing levels of cyclic adenosine monophosphate and cyclic guanosine monophosphate. The limiting factor in the use of the ASAdipyridamole combination is the latter's potential effects on coronary perfusion. Dipyridamole can cause coronary vasodilation, which results in increased blood flow to nonstenosed coronary arteries. The result is that myocardial ischemia may be provoked during exercise. As such, the current American College of Cardiology/American Heart Association guidelines recommend that dipyridamole not be used in patients with chronic stable angina. 31 However, this recommendation was based on shortacting dipyridamole, which also reduced myocardial ischemia in a similar number of patients in the study quoted by these guidelines. 32 With the use of sustained-release dipyridamole, no increase in cardiac events was observed in subjects with prior coronary artery disease. 33 Thienopyridines block adenosine-diphosphate-mediated platelet aggregation. Ticlopidine was the first of this class of drug to be studied for stroke prevention. One clinical trial demonstrated that patients treated with ticlopidine had similar rates of stroke as those treated with ASA 28 (Table 1). However, serious granulocytopenia associated with ticlo- Leukocytes localize in the earliest atherosclerotic lesions, binding to vascular cell adhesion molecules (VCAM-1) on the vascular endothelium and migrating into the intima. This initiates and perpetuates a local inflammatory response. Monocytes mature into lipid-scavenging macrophages and subsequently foam cells. T-lymphocytes express inflammatory cytokines, which cont...

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We are undertaking a rigorous evaluation of a population-based approach to improving quality of transient ischaemic attack care. Whether positive or negative, our work should provide important insights for all potential stakeholders.

THE CANADIAN JOURNAL OF NEUROLOGICAL SCIENCESStroke prevention clinics (SPCs) are a relatively recent and evolving phenomenon in the delivery of specialized health care. Patients can be seen very early after a cerebrovascular event and stated targets for risk assessment such as hypertension, hyperlipidemia, smoking, atrial fibrillation, and internal carotid artery stenosis can be made. In addition, appropriate medical and surgical interventions such as antiplatelet or anticoagulation treatment, blood pressure management, cholesterol lowering agents, and carotid endarterectomy can be initiated for secondary prevention. 1.2 Little is known about the referral patterns to SPCs ABSTRACT: Objective: To evaluate the referral patterns of patients to a stroke prevention clinic (SPC) and to test the adequacy of prereferral diagnosis and management of modifiable risk factors for stroke. Methods: We collected prospective data on consecutive patients referred to the SPC at University of Alberta Hospital in Edmonton, Alberta, Canada. Outcome measures included: alternate diagnoses to stroke or transient ischemic attack (TIA), uncontrolled or undiagnosed hypertension, hyperlipidemia and diabetes, therapies, and investigations leading to carotid endarterectomy. Results: Two thousand and eleven patients were referred to SPC. Nearly 25% of the referrals originated from the emergency room and the rest from general physicians. Of the referrals, 68.7% were confirmed as TIA or stroke at the SPC. Among 1381 patients with TIA or stroke, 736 had history of hypertension. Uncontrolled hypertension was found in 265 patients (36.0% of those with hypertension: 95% CI: 32.5-39.5) while undiagnosed hypertension was found in 103 (15.9% of those without hypertension: 95%CI: 13.14-18.79). History of hyperlipidemia was present in 451 patients (32.6%) and 356 (78.9%: 95% CI: 75.2-82.69) of these patients were not at target for secondary prevention. Among 930 patients without history of hyperlipidemia, 739 (79.5%: 95% CI: 76.8-82.1) were diagnosed with hyperlipidemia through the SPC. Fasting blood glucose levels above 7.1 mmol/L in patients with and without history of diabetes were 221 (79.2%: 95% CI: 74.5-83.9) and 66 (6%: 95%CI: 4.6-7.4) respectively. Conclusions: Management of risk factors for stroke needs improvement. SPCs should consider actively managing the classical modifiable risk factors of stroke. RÉSUMÉ: L'impact d'une clinique de prévention de l'accident vasculaire cérébral sur le diagnostic des facteurs de risque modifiables de l'accident vasculaire cérébral. Objectif: Évaluer le profil d'orientation de patients vers une clinique de prévention le l'accident vasculaire cérébral (CPAVC) et la pertinence du diagnostic et de la prise en charge des facteurs de risque modifiables de l'accident vasculaire cérébral (AVC). Méthodes:Nous avons recueilli des données prospectives sur des patients consécutifs référés à la CPAVC du University of Alberta Hospital à Edmonton, Alberta, Canada. Nous avons évalué les résultats suivants: les diagnostics a...

The reversed OA sign at 50 to 60 mm depth is very specific for identifying cICA occlusion or critical stenosis. When OA flow is anterograde, a low mean flow velocity or pulsatility index is also useful to identify cICA critical stenosis or occlusion.