Effects of a Province-wide Triaging System for TIA: The ASPIRE Intervention.

BACKGROUND AND OBJECTIVES: Urgent transient ischemic attack (TIA) management to reduce stroke recurrence is challenging, particularly in rural and remote areas. In Alberta, Canada, despite an organized stroke system, data from 1999 to 2000 suggested that stroke recurrence after TIA was as high as 9.5% at 90 days. Our objective was to determine whether a multifaceted population-based intervention resulted in a reduction in recurrent stroke after TIA. METHODS: In this quasi-experimental health services research intervention study, we implemented a TIA management algorithm across the entire province, centered around a 24-hour physician's TIA hotline and public and health provider education on TIA. From administrative databases, we linked emergency department discharge abstracts to hospital discharge abstracts to identify incident TIAs and recurrent strokes at 90 days across a single payer system with validation of recurrent stroke events. The primary outcome was recurrent stroke; with a secondary composite outcome of recurrent stroke, acute coronary syndrome, and all-cause death. We used an interrupted time series regression analysis of age-adjusted and sex-adjusted stroke recurrence rates after TIA, incorporating a 2-year preimplementation period (2007-2009), a 15-month implementation period, and a 2-year postimplementation period (2010-2012). Logistic regression was used to examine outcomes that did not fit the time series model. RESULTS: We assessed 6,715 patients preimplementation and 6,956 patients postimplementation. The 90-day stroke recurrence rate in the pre-Alberta Stroke Prevention in TIA and mild Strokes (ASPIRE) period was 4.5% compared with 5.3% during the post-ASPIRE period. There was neither a step change (estimate 0.38; p = 0.65) nor slope change (parameter estimate 0.30; p = 0.12) in recurrent stroke rates associated with the ASPIRE intervention implementation period. Adjusted all-cause mortality (odds ratio 0.71, 95% CI 0.56-0.89) was significantly lower after the ASPIRE intervention. DISCUSSION: The ASPIRE TIA triaging and management interventions did not further reduce stroke recurrence in the context of an organized stroke system. The apparent lower mortality postintervention may be related to improved surveillance after events identified as TIAs, but secular trends cannot be excluded. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that a standardized population-wide algorithmic triage system for patients with TIA did not reduce recurrent stroke rate.

Case management reduces global vascular risk after stroke: secondary results from the The preventing recurrent vascular events and neurological worsening through intensive organized case-management randomized controlled trial.

BACKGROUND: Survivors of ischemic stroke/transient ischemic attack (TIA) are at high risk for other vascular events. We evaluated the impact of 2 types of case management (hard touch with pharmacist or soft touch with nurse) added to usual care on global vascular risk. METHODS: This is a prespecified secondary analysis of a 6-month trial conducted in outpatients with recent stroke/TIA who received usual care and were randomized to additional monthly visits with either nurse case managers (who counseled patients, monitored risk factors, and communicated results to primary care physicians) or pharmacist case managers (who were also able to independently prescribe according to treatment algorithms). The Framingham Risk Score [FRS]) and the Cardiovascular Disease Life Expectancy Model (CDLEM) were used to estimate 10-year risk of any vascular event at baseline, 6 months (trial conclusion), and 12 months (6 months after last trial visit). RESULTS: Mean age of the 275 evaluable patients was 67.6 years. Both study arms were well balanced at baseline and exhibited reductions in absolute global vascular risk estimates at 6 months: median 4.8% (Interquartile range (IQR) 0.3%-11.3%) for the pharmacist arm versus 5.1% (IQR 1.9%-12.5%) for the nurse arm on the FRS (P = .44 between arms) and median 10.0% (0.1%-31.6%) versus 12.5% (2.1%-30.5%) on the CDLEM (P = .37). These reductions persisted at 12 months: median 6.4% (1.2%-11.6%) versus 5.5% (2.0%-12.0%) for the FRS (P = .83) and median 8.4% (0.1%-28.3%) versus 13.1% (1.6%-31.6%) on the CDLEM (P = .20). CONCLUSIONS: Case management by nonphysician providers is associated with improved global vascular risk in patients with recent stroke/TIA. Reductions achieved during the active phase of the trial persisted after trial conclusion.

Case management for blood pressure and lipid level control after minor stroke: PREVENTION randomized controlled trial.

BACKGROUND: Optimization of systolic blood pressure and lipid levels are essential for secondary prevention after ischemic stroke, but there are substantial gaps in care, which could be addressed by nurse- or pharmacist-led care. We compared 2 types of case management (active prescribing by pharmacists or nurse-led screening and feedback to primary care physicians) in addition to usual care. METHODS: We performed a prospective randomized controlled trial involving adults with recent minor ischemic stroke or transient ischemic attack whose systolic blood pressure or lipid levels were above guideline targets. Participants in both groups had a monthly visit for 6 months with either a nurse or pharmacist. Nurses measured cardiovascular risk factors, counselled patients and faxed results to primary care physicians (active control). Pharmacists did all of the above as well as prescribed according to treatment algorithms (intervention). RESULTS: Most of the 279 study participants (mean age 67.6 yr, mean systolic blood pressure 134 mm Hg, mean low-density lipoprotein [LDL] cholesterol 3.23 mmol/L) were already receiving treatment at baseline (antihypertensives: 78.1%; statins: 84.6%), but none met guideline targets (systolic blood pressure ≤ 140 mm Hg, fasting LDL cholesterol ≤ 2.0 mmol/L). Substantial improvements were observed in both groups after 6 months: 43.4% of participants in the pharmacist case manager group met both systolic blood pressure and LDL guideline targets compared with 30.9% in the nurse-led group (12.5% absolute difference; number needed to treat = 8, p = 0.03). INTERPRETATION: Compared with nurse-led case management (risk factor evaluation, counselling and feedback to primary care providers), active case management by pharmacists substantially improved risk factor control at 6 months among patients who had experienced a stroke. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT00931788.

The Alberta Stroke Prevention in TIAs and mild strokes (ASPIRE) intervention: rationale and design for evaluating the implementation of a province-wide TIA triaging system.

RATIONALE: Stroke risk after transient ischaemic attack is high and, it is a challenge worldwide to provide urgent assessment and preventive services to entire populations. AIMS: To determine whether a province-wide transient ischaemic attack Triaging algorithm and transient ischaemic attack hotline (the Alberta Stroke Prevention in transient ischaemic attacks and mild strokes intervention) can reduce the rate of stroke recurrence following transient ischaemic attack across the population of Alberta, Canada (population 3·7 million, 90-day rate of post-stroke transient ischaemic attack currently 9·5%). It also seeks to improve upon current transient ischaemic attack triaging rules by incorporating time from symptom onset as a predictive variable. DESIGN: The transient ischaemic attack algorithm and hotline were developed with a broad consensus of clinicians, patients, policy-makers, and researchers and based on local adaptation of the work of others and research and insights developed within the province. Because neither patient-level nor region-level randomization was possible, we conducted a quasi-experimental design examining changes in the post-transient ischaemic attack rate of stroke recurrence before and after the 15-month implementation period using an interrupted time-series regression analysis. The design controls for changes in case-mix, co-interventions, and secular trends. A prospective transient ischaemic attack cohort will also be concurrently created with telephone follow-up at seven-days and 90 days as well as passive follow-up over the longer term using linkages to provincial healthcare administrative databases. STUDY OUTCOMES: The primary outcome measure is the change in recurrence rate of stroke following transient ischaemic attack at seven-days and 90 days, comparing a period of two-years before vs. two-years after the intervention is implemented. All cases of recurrent stroke will be validated. Secondary outcomes include functional status, hospitalizations, morbidity, and mortality. CONCLUSIONS: 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 preventing recurrent vascular events and neurological worsening through intensive organized case-management (PREVENTION) trial protocol [clinicaltrials.gov identifier: NCT00931788].

BACKGROUND: Survivors of transient ischemic attack (TIA) or stroke are at high risk for recurrent vascular events and aggressive treatment of vascular risk factors can reduce this risk. However, vascular risk factors, especially hypertension and high cholesterol, are not managed optimally even in those patients seen in specialized clinics. This gap between the evidence for secondary prevention of stroke and the clinical reality leads to suboptimal patient outcomes. In this study, we will be testing a pharmacist case manager for delivery of stroke prevention services. We hypothesize this new structure will improve processes of care which in turn should lead to improved outcomes. METHODS: We will conduct a prospective, randomized, controlled open-label with blinded ascertainment of outcomes (PROBE) trial. Treatment allocation will be concealed from the study personnel, and all outcomes will be collected in an independent and blinded manner by observers who have not been involved in the patient's clinical care or trial participation and who are masked to baseline measurements. Patients will be randomized to control or a pharmacist case manager treating vascular risk factors to guideline-recommended target levels. Eligible patients will include all adult patients seen at stroke prevention clinics in Edmonton, Alberta after an ischemic stroke or TIA who have uncontrolled hypertension (defined as systolic blood pressure (BP) > 140 mm Hg) or dyslipidemia (fasting LDL-cholesterol > 2.00 mmol/L) and who are not cognitively impaired or institutionalized. The primary outcome will be the proportion of subjects who attain 'optimal BP and lipid control'(defined as systolic BP < 140 mm Hg and fasting LDL cholesterol < 2.0 mmol/L) at six months compared to baseline; 12-month data will also be collected for analyses of sustainability of any effects. A variety of secondary outcomes related to vascular risk and health-related quality of life will also be collected. CONCLUSIONS: Nearly one-quarter of those who survive a TIA or minor stroke suffer another vascular event within a year. If our intervention improves the provision of secondary prevention therapies in these patients, the clinical (and financial) implications will be enormous.

Bedside emergency transcranial Doppler diagnosis of severe carotid disease using orbital window examination.

BACKGROUND: Identifying internal carotid artery (ICA) stenosis in the acute stroke setting can provide clinically useful information. Transcranial Doppler (TCD) through the orbital window is an easy test to perform and to track and identify different vessels. Previous TCD studies have suggested that a reversed ophthalmic artery (OA) flow is a useful collateral pattern to predict ICA disease. The authors sought to evaluate the TCD orbital window for predicting cervical ICA (cICA) stenosis in the setting of acute stroke and TIA. METHOD: Power M-mode/TCD was performed in acute stroke and transient ischemic attack patients at 2 institutions. Each orbital window depth was detected on M-mode and evaluated for the direction of flow and resistance pattern. Gold standard for comparison was carotid evaluation using carotid duplex, computed tomography angiogram, or conventional angiography. The assessment of cICA disease was categorized by degree of stenosis or occlusion. RESULTS: A total of 216 transorbital exams were performed in 117 patients. Twenty-five cICA occlusions and 8 critical cICA stenoses (>or=95%) were identified by gold standard imaging. Reversed OA flow at 50 to 60 mm depth revealed high specificity (100%; confidence interval [CI], 97.6%-100.0%) and good sensitivity (75%; CI, 53.3%-90.2%) for identifying cICA occlusion or critical stenosis (>or=95%). Low pulsatility index (<1.2) and mean flow velocity (<15 cm/s) discriminated critical severe ICA stenosis or occlusion when OA flow was anterograde with good sensitivity (87.2%) and specificity (95.2%). CONCLUSION: 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.

The impact of a stroke prevention clinic in diagnosing modifiable risk factors for stroke.

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.

Current and future concepts in stroke prevention.

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, lipid-lowering agents and carotid endarterectomy for stroke prevention.

Improved detection of microbubble signals using power M-mode Doppler.

UNLABELLED: 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 (rho=0.97) with PMD MBS counts in MCA and similarly in anterior cerebral arteries (ACA) (rho=0.79). When PMD microbubble counts in the ACA and MCA were summed, a clear 2-fold difference emerged between 2 modalities (P<0.001). CONCLUSIONS: When compared with spectral TCD, PMD detects more MBS with higher counts by identifying ACA as well as MCA emboli. Pitfalls of overcounting emboli with PMD can be avoided by following such criteria.

Atrial myxoma as a cause of stroke: case report and discussion.

Cardiac myxoma is a source of emboli to the central nervous system and elsewhere in the vascular tree. However, nonspecific systemic symptoms and minor embolic phenomena may be overlooked in the absence of any history of cardiac problems. In this situation, cardiac investigations may not be performed, and diagnosis of this rare condition may be delayed until the onset of more significant embolic disease, such as stroke with functional impairment, as in the case reported here. The clinical presentation of cardiac myxoma is discussed, along with appropriate investigations and treatment, which may prevent such sequelae.

"Malignant" carotid artery dissection.

PURPOSE: Carotid artery dissection resulting in occlusion or severe narrowing and massive intracranial embolism can result in life-threatening hemispheric ischemia. Aggressive endovascular and microsurgical measures may be necessary to salvage life and minimize stroke morbidity in this extreme situation. PATIENTS AND METHODS: We have treated two middle-aged women who presented within an hour of spontaneous cervical internal carotid artery (ICA) dissection causing hemiplegia, forced head and eye deviation, and declining consciousness. The first patient had a carotid occlusion through which a catheter could not be passed, so intracranial thrombolysis was achieved through a microcatheter navigated through the posterior circulation. Surgical intimectomy and thrombectomy of the dissected ICA was then carried out using an intraoperative Fogarty arterial embolectomy catheter passed up the dissected ICA, followed by endovascular stenting of the reopened cervical ICA. The second patient underwent intracranial microsurgical embolectomy and, after an unsuccessful attempt of stenting the dissected and severely narrowed cervical ICA, surgical reopening again with a Fogarty catheter. Both patients suffered basal ganglionic infarcts but most of the middle cerebral artery territories were preserved and the patients made satisfactory recoveries. CONCLUSIONS: "Malignant" carotid artery dissection causing occlusion or near occlusion with intracranial embolism is an important cause of severe and life-threatening hemispheric ischemia. Treatment should include aggressive endovascular and microsurgical interventions when the hemisphere is at risk.