R.M. Gilmore

Impact of acute blood pressure variability on ischemic stroke outcome

Background: The authors previously reported a low initial emergency department (ED) blood pressure (BP) to be associated with a significantly increased risk of death at 90 days. In this article, they examine the impact of acute BP variability following onset of ischemic stroke. Methods: The study cohort consisted of 71 patients with stroke onset less than 24 hours. BP measurements were obtained every 5 minutes for the duration of the patient’s ED stay. During the first 180 minutes, the median number of readings per patient was 9 (range 2 to 30). Results: The baseline median systolic (sBP) and diastolic (dBP) BPs were not different for the patients that died within 90 days compared with those that were alive (p = 0.91 for sBP and p = 0.27 for dBP). Patients who died within 90 days had a greater differential in their dBP during the first 180 minutes than the patients that were alive after 90 days (median 44.5 vs 25 mm Hg; Wilcoxon rank sum test, p < 0.001). A similar result was observed for sBP (median 47 vs 30 mm Hg; p = 0.047). Conclusion: Wide fluctuation of blood pressure in the first 3 hours of the emergency department stay in patients with acute ischemic stroke appears to be associated with an increased risk of death at 90 days.

Initial emergency department blood pressure as predictor of survival after acute ischemic stroke

Objective: To evaluate the association of diastolic blood pressure (dBP), systolic blood pressure (sBP), and mean arterial pressure (MAP) in the emergency department (ED) with mortality within 90 days in patients with acute ischemic stroke (AIS). Methods: This observational study was conducted at an ED with an annual census of 70,000 visits, with approximately 500 for AIS. The cohort consisted of 357 patients who presented to the ED within 24 hours of stroke symptom onset. sBP and dBP were measured at triage by a nurse blinded to the study. The duration of follow-up was limited to the first 90 days following ED presentation. BP levels were categorized as low, normotensive, and high after examining scatter plots of a patients risk of death adjusted for duration of follow-up vs dBP, sBP, and MAP. These BP categories were evaluated using indicator variables in Cox proportional hazards models, after adjusting for age, sex, and the National Institute of Health Stroke Scale (NIHSS) score. Results: Patients with low BP (dBP <70, sBP <155, or MAP <100 mm Hg) were significantly more likely to die within 90 days than those with BP in the normotensive range (dBP 70 to 105, sBP 155 to 220, MAP 100 to 140 mm Hg). These associations were significant even after adjusting for age, gender, and NIHSS score. Conclusions: There appears to be an optimal acute BP range below which early mortality is greater following AIS, suggesting avoidance of hypotension in the first 24 hours.

The role of hyperglycemia in acute ischemic stroke

Stroke remains a leading cause of death and long-term disability in the developed world. Reperfusion and anti-thrombotic therapies are of limited benefit for the majority of patients following acute ischemic stroke, and increasing interest has focused on therapeutic approaches that seek to modulate infarct evolution. Animal and human studies have linked hyperglycemia in the acute phase of ischemic stroke to worse clinical outcomes regardless of the presence of pre-existing diabetes mellitus. Experimental data suggest that elevated blood glucose may directly contribute to infarct expansion through a number of maladaptive metabolic pathways, and that treatment with insulin may attenuate these adverse effects. In this review, we analyze the relationship between elevated serum glucose and acute cerebrovascular ischemia, and critically appraise the potential of a clinical strategy that targets euglycemia in all acute stroke patients.

Percutaneous Clot Removal Devices in Acute Ischemic Stroke: A Systematic Review and Meta-analysis

We conducted a systematic review and meta-analysis of mechanical thrombectomy in the treatment of ischemic stroke and assessed factors for technical and clinical success and survival. We searched the literature using MEDLINE and EMBASE for January 1, 2000, through March 1, 2006. Studies were limited to those in human beings; there were no language or study design restrictions. Validity assessment was performed using the Newcastle-Ottawa Scale. The pooled cohort was compared with a historical cohort matched for sex, age, and National Institutes of Health Stroke Survey score. The search yielded 114 publications. Two authors determined inclusibility (interrater agreement, kappa = 0.94). Mean preprocedure National Institutes of Health Stroke Survey score was 20.4. The middle cerebral artery (36%) and the posterior circulation (38%) were the most frequently occluded areas. The clot was accessible in 85% of the patients. Hemorrhage occurred in 22% of the patients. Of 81 patients with concurrent thrombolysis, 18.5% had hemorrhage compared with 27.3% of 66 patients without thrombolysis (P = .21). Of the 126 patients with accessible clots, 36% had a good modified Rankin score (<or=2) and 29% died; in patients with inaccessible clots, 24% had a good modified Rankin score and 38% died. Factors associated with clinical success were younger age (P = .001) and lower National Institutes of Health Stroke Survey score at admission to the hospital (P = .001). Compared with a matched cohort, patients who received mechanical intervention were 14.8 times more likely to have a good modified Rankin score (95% confidence interval, 4.4-50.0; P < .001). Percutaneous mechanical embolectomy in the treatment of acute ischemic stroke is feasible and seems to provide an option for some patients seen after the interval for administration of intravenous tissue plasminogen activator therapy has elapsed.

Effect of anticoagulant and antiplatelet therapy in patients with spontaneous intra-cerebral hemorrhage: Does medication use predict worse outcome?

OBJECTIVES To assess the impact of anticoagulants and antiplatelet agents on the severity and outcome of spontaneous non-traumatic intra-cerebral hemorrhage (ICH). To evaluate associations between reversal of anticoagulation and mortality/morbidity in these patients. METHODS Data was collected on a consecutive cohort of adults presenting with ICH to an academic Emergency Department over a 3-year period starting January 2006. RESULTS The final cohort of 245 patients consisted of 125 females (51.1%). The median age of the cohort was 73 years [inter-quartile (IQR) range of 59-82 years]. Antiplatelet (AP) use was seen in 32.6%, 18.4% were using anticoagulant (AC) and 8.9% patients were on both drugs (AC+AP). Patients on AC had significantly higher INR (median 2.3) and aPTT (median 31 s) when compared to patients not on AP/AC (median INR 1.0, median aPTT 24s; p<0.001). Similarly patients on AC+AP also had higher INR (median 1.9) and aPTT (median 30s) when compared to those not on AC/AP (p<0.001). Hemorrhage volumes were significantly higher for patients on AC alone (median 64.7 cm(3)) when compared to those not on either AC/AP (median 27.2 cm(3); p=0.05). The same was not found for patients using AP (median volume 20.5 cm(3); p=0.813), or both AC+AP (median volume 27.7 cm(3); p=0.619). Patients on AC were 1.43 times higher at risk to have intra-ventricular extension of hemorrhage (IVE) as compared to patients not on AC/AP (95% CI 1.04-1.98; p=0.035). There was no relationship between the use of AC/AP/AC+AP and functional outcome of patients. Patients on AC were 1.74 times more likely to die within 7 days (95% CI 1.0-3.03; p=0.05). No relationship was found between use of AP or AC+AP use and mortality. Of the 82 patients with INR>1.0, 52 patients were given reversal (minimum INR 1.4, median 2.3). Therapy was heterogeneous, with fresh frozen plasma (FFP) being the most commonly used agent (86.5% patients, median dose 4U). Vitamin K, activated factor VIIa and platelets were the other agents used. Post reversal, INR normalized within 24h (median 1.2, IQR 1.1-1.3). There was no association between reversal and volume of hemorrhage, IVE, early mortality (death<7 days) or functional outcome. CONCLUSIONS Anticoagulated patients were at 1.7 times higher risk of early mortality after ICH. Reversal of INR to normal did not influence mortality or functional outcome.

Female Gender Remains an Independent Risk Factor for Poor Outcome after Acute Nontraumatic Intracerebral Hemorrhage

Objective. To study whether gender influences outcome after intracerebral hemorrhage (ICH). Methods. Cohort study of 245 consecutive adults presenting to the emergency department with spontaneous ICH from January 2006 to December 2008. Patients with subarachnoid hemorrhage, extradural hemorrhage, and recurrence of hemorrhage were excluded. Results. There were no differences noted between genders in stroke severity (NIHSS) at presentation, ICH volume, or intraventricular extension (IVE) of hemorrhage. Despite this, females had 1.94 times higher odds of having a bad outcome (modified Rankin score (mRs) ≥3) as compared to males (95% CI 1.12 to 3.3) and 1.84 times higher odds of early mortality (95% CI 1.02–3.33). analyzing known variables influencing mortality in ICH, the authors found that females did have higher serum glucose levels on arrival (P = 0.0096) and 4.2 times higher odds for a cerebellar involvement than males (95% CI 1.63–10.75). After adjusting for age, NIHSS, glucose levels, hemorrhage volume, and IVE, female gender remained an independent predictor of early mortality (P = 0.0127). Conclusions. Female gender may be an independent predictor of early mortality in ICH patients, even after adjustment for stroke severity, hemorrhage volume, IVE, serum glucose levels, and age.

Statins in Ischemic Stroke: Just Low-Density Lipoprotein Lowering or More?

BACKGROUND Statins have been shown to improve the functional outcome of patients after an ischemic stroke. We hypothesized that daily statin intake improves functional outcome after an acute ischemic stroke in patients with low-density lipoprotein (LDL) less than or equal to 100 mg/dL. METHODS This was a prospective cohort study during a 22-month period of patients presenting with an acute ischemic stroke and lipid profiles measured. The functional disability was determined using modified Rankin scale score (0-2 good outcome, 3-6 bad outcome) at discharge. Chi-square test for binary data and nonparametric tests for nonnormally distributed variables were used for analysis. RESULTS Of 508 patients, 207 presented with an LDL of 100 mg/dL or less and were included in the analysis. There was no significant difference in admission stroke severity (National Institutes of Health Stroke Scale [NIHSS]; P = .18), age (P = .31), and sex (P = .06) between those taking statins and not taking statins. Patients with LDL less than or equal to 100 mg/dL and taking statins (n = 100) were significantly more likely to have a good functional outcome (odds ratio 1.91; 95% confidence interval 1.05-3.47) when compared with those not on the medication. After adjusting for age, sex, and NIHSS, statin intake still predicted a better functional outcome (P < .0001). CONCLUSION Daily statin intake appears to result in a better functional outcome after an ischemic stroke in patients with ideal LDL levels (<or=100 mg/dL) before and after adjusting for age and stroke severity. Pleiotropic effects of statins may play a role in this.

An Assessment of the Incremental Value of the ABCD2 Score in the Emergency Department Evaluation of Transient Ischemic Attack

STUDY OBJECTIVE We study the incremental value of the ABCD2 score in predicting short-term risk of ischemic stroke after thorough emergency department (ED) evaluation of transient ischemic attack. METHODS This was a prospective observational study of consecutive patients presenting to the ED with a transient ischemic attack. Patients underwent a full ED evaluation, including central nervous system and carotid artery imaging, after which ABCD2 scores and risk category were assigned. We evaluated correlations between risk categories and occurrence of subsequent ischemic stroke at 7 and 90 days. RESULTS The cohort consisted of 637 patients (47% women; mean age 73 years; SD 13 years). There were 15 strokes within 90 days after the index transient ischemic attack. At 7 days, the rate of stroke according to ABCD2 category in our cohort was 1.1% in the low-risk group, 0.3% in the intermediate-risk group, and 2.7% in the high-risk group. At 90 days, the rate of stroke in our ED cohort was 2.1% in the low-risk group, 2.1% in the intermediate-risk group, and 3.6% in the high-risk group. There was no relationship between ABCD2 score at presentation and subsequent stroke after transient ischemic attack at 7 or 90 days. CONCLUSION The ABCD2 score did not add incremental value beyond an ED evaluation that includes central nervous system and carotid artery imaging in the ability to risk-stratify patients with transient ischemic attack in our cohort. Practice approaches that include brain and carotid artery imaging do not benefit by the incremental addition of the ABCD2 score. In this population of transient ischemic attack patients, selected by emergency physicians for a rapid ED-based outpatient protocol that included early carotid imaging and treatment when appropriate, the rate of stroke was independent of ABCD2 stratification.

Cardioembolic but Not Other Stroke Subtypes Predict Mortality Independent of Stroke Severity at Presentation

Introduction. Etiology of acute ischemic stroke (AIS) is known to significantly influence management, prognosis, and risk of recurrence. Objective. To determine if ischemic stroke subtype based on TOAST criteria influences mortality. Methods. We conducted an observational study of a consecutive cohort of patients presenting with AIS to a single tertiary academic center. Results. The study population consisted of 500 patients who resided in the local county or the surrounding nine-county area. No patients were lost to followup. Two hundred and sixty one (52.2%) were male, and the mean age at presentation was 73.7 years (standard deviation, SD = 14.3). Subtypes were as follows: large artery atherosclerosis 97 (19.4%), cardioembolic 144 (28.8%), small vessel disease 75 (15%), other causes 19 (3.8%), and unknown 165 (33%). One hundred and sixty patients died: 69 within the first 30 days, 27 within 31–90 days, 29 within 91–365 days, and 35 after 1 year. Low 90-, 180-, and 360-day survival was seen in cardioembolic strokes (67.1%, 65.5%, and 58.2%, resp.), followed for cryptogenic strokes (78.0%, 75.3%, and 71.1%). Interestingly, when looking into the cryptogenic category, those with insufficient information to assign a stroke subtype had the lowest survival estimate (57.7% at 90 days, 56.1% at 180 days, and 51.2% at 1 year). Conclusion. Cardioembolic ischemic stroke subtype determined by TOAST criteria predicts long-term mortality, even after adjusting for age and stroke severity.

Knowledge of signs, treatment and need for urgent management in patients presenting with an acute ischaemic stroke or transient ischaemic attack: A prospective study

Objective: To assess stroke awareness among patients presenting to the emergency department with an acute ischaemic stroke or transient ischaemic attack (TIA). Methods: A consecutive cohort of patients presenting with a cerebrovascular event was prospectively enrolled over a 15-month period and questionnaires were administered. If the patient was unable to respond to the questions or answer the questionnaire, it was administered to the primary caregiver. Comprehension of having a cerebrovascular event, reason for delay in presentation, mode of arrival and knowledge of treatment modalities were determined. Results: Only 42% of 400 patients thought they were having a stroke or TIA. The median time to presentation was 3.4 h. Delayed presentation was almost equal in men and women. When asked about onset, 19.4% thought that a stroke came on gradually and only 51.9% thought immediate presentation was crucial. 20.8% of patients had heard of thrombolysis. Conclusion: Community knowledge of ischaemic stroke needs to be enhanced so that individuals present earlier, leading to timely management.