Susanna Horner

Effect of Blood Pressure During the Acute Period of Ischemic Stroke on Stroke Outcome A Tertiary Analysis of the GAIN International Trial

Background and Purpose— The effects of blood pressure (BP) and its fluctuations during the acute phase on the clinical course of ischemic stroke are incompletely understood. We tested the hypotheses that baseline mean arterial BP [MAP=(2×diastolic BP+systolic BP)/3], weighted average MAP, and an increase or decrease of >30% from baseline MAP are independently associated with stroke outcome. Methods— We studied the 1455 patients with ischemic stroke in the Glycine Antagonist (Gavestinel) in Neuroprotection (GAIN) International Trial. BP management was at the discretion of investigators and was measured at 0, 0.5, 4, 12, 12.25, 60, and 60.25 hours. Outcome was assessed by mortality, Barthel Index (dead or 0 to 55 versus 60 to 90 versus ≥95), National Institutes of Health Stroke Scale (NIHSS) score (dead or ≥2), and Rankin Scale (dead or ≥2). Cox proportional-hazards and stepwise logistic regression modeling corrected for demography, medical history, stroke severity, and clinical subtype. Results— Elevated weighted average MAP was associated with poor outcome assessed by mortality at 3 months (hazard ratio, 1.16; 1.06 to 1.27 per 10 mm Hg), NIHSS score (odds ratio [OR] 1.14; 95% confidence interval [CI], 1.01 to 1.28), and Barthel Index at 1 month (OR, 1.12; 95% CI, 1.03 to 1.23). A 30% increase from baseline MAP was associated with poor outcome assessed by NIHSS score and Barthel Index at 1 and 3 months and by Rankin score at 1 month (OR, 2.01; 95% CI, 1.16 to 3.49 to OR, 3.03; 95% CI, 1.30 to 7.02). Conclusions— Baseline MAP was not associated with poor ischemic stroke outcome. However, variables describing the course of BP over the first 2.5 days have a marked and independent relationship with 1- and 3-month outcome.

C-Reactive Protein, Carotid Atherosclerosis, and Cerebral Small-Vessel Disease Results of the Austrian Stroke Prevention Study

Background and Purpose— C-reactive protein (CRP) is an inflammatory marker known to be a risk factor for stroke. We examined the associations between CRP, carotid atherosclerosis, white matter lesions, and lacunes as manifestations of cerebral large- and small-vessel disease. Methods— In the community-based Austrian Stroke Prevention Study, CRP concentrations were measured by a highly sensitive assay in 700 participants at baseline. All underwent carotid duplex scanning, and a subset of 505 subjects underwent brain magnetic resonance imaging. Imaging was repeated after 3 and 6 years. We graded carotid atherosclerosis in both common and internal carotid arteries on a 5-point scale and calculated the sum of scores as an index of the severity of carotid atherosclerosis. The volume of white matter lesions and the number of lacunes were considered small vessel disease–related brain abnormalities. Results— After adjustment for vascular risk factors, the severity and progression of extracranial carotid atherosclerosis increased with increasing quintiles of CRP. Only study participants in the fourth and fifth quintile (>2.50 mg/L) had significantly more baseline atherosclerosis and greater progression when we used the first quintile (<0.80 mg/L) as a reference. No interactions were seen between CRP quintiles and vascular risk factors for carotid atherosclerosis. The associations between severity and progression of small vessel disease–related brain abnormalities and CRP were nonsignificant. Conclusions— We found evidence for differential effects of CRP in different beds of the arterial brain supply. CRP was a marker for active carotid atherosclerosis but not for small vessel disease–related brain lesions.

Sex-Related Differences of Acute Stroke Unit Care: Results From the Austrian Stroke Unit Registry

Background and Purpose— Sex-related differences in quality of acute stroke care are an important concern with limited data available, specifically regarding stroke unit (SU) setting. We used the prospective nationwide Austrian SU registry to address this issue. Methods— Our analysis covered an 8-year time period (January 2005 to December 2012) during which all patients with transient ischemic attack or ischemic stroke admitted to 1 of 35 Austrian SU had been captured in the registry. These data were analyzed for age-adjusted preclinical and clinical characteristics and quality of acute stroke care in men and women. In addition, we assessed the outcome at 3 months in multivariate analysis. Results— A total of 47 209 individuals (47% women) had received SU care. Women were significantly older (median age: 77.9 versus 70.3 years), had higher pre-existing disability and more severe strokes. Correcting for age, no significant sex-related differences in quality of care were identified with comparable onset-to-door times, times to and rates of neuroimaging, as well as door-to-needle times and rates of intravenous thrombolysis (14.5% for both sexes). Despite equal acute stroke care and a comparable rate of neurorehabilitation, women had a worse functional outcome at 3-month follow-up (modified Rankin scale 3–5: odds ratio, 1.26; 95% confidence interval [1.17–1.36]), but a lower mortality (odds ratio, 0.70; 95% confidence interval [0.78–0.88]) after correcting for confounders. Conclusions— We identified no disproportions in quality of care in the acute SU setting between men and women, but the outcome was significantly different. Further studies on the poststroke period including socioeconomic aspects are needed to clarify this finding.

EEG, CT and neurosonographic findings in patients with postischemic seizures

Seventy-two patients with postischemic seizures were evaluated with electroencephalography (EEG), computerized tomography (CT) and neurosonography. There were 24% early-onset and 76% late-onset initial seizures. Early-onset seizure was more likely to be simple partial (53%), whereas late-onset seizure was more likely to be primarily generalized (56%). 76% early-onset and 80% late-onset seizures were single. Status epilepticus was more frequent in early-onset that late-onset seizures (p = 0.023). The possibility of recurrence was greater in late-onset than early-onset seizures (p < 0.001). 88% patients had EEG abnormalities, and the most common finding was focal slowing. 75% patients had cerebral infarctions on CT scan, and the majority of them involved cortex. 89% postischemic seizures had carotid lesions which mostly were carotid plaques < 50%. We failed to find these data to be useful in predicting the time of onset of initial seizures after acute ischemic stroke and recurrence.

Prevalence of White Matter and Periventricular Magnetic Resonance Hyperintensities in Asymptomatic Volunteers

Magnetic resonance imaging (MRI) of 101 asymptomatic volunteers ranging in age from 31 to 84 years (mean, 55 yr) was performed to determine the prevalence and extent of unexpected white matter (WMH) and periventricular hyperintensities (PVH) in the “normal” population. Twenty‐nine had followup studies after 11 to 28 months (mean, 15 mo). Predominantly punctate WMHs were present in 48%. Increasing prevalence was associated with aging and was significantly higher in individuals with major cerebrovascular risk factors (P < 0.05). PVH was noted in 45% and consisted mainly of caps and lines. Volunteers with more extensive WMHs (6%) or PVH (4%) had risk factors or were above 60 years of age. The repeat scans exhibited no significant changes.

Right-to-Left Shunt Assessed by Contrast Transcranial Doppler Sonography New Insights

Objective. Simple diagnostic techniques such as contrast transcranial Doppler sonography (cTCDS) are popular for assessing a right‐to‐left shunt (RLS) because of their high sensitivity. In this study, we applied cTCDS to a large patient group with a patent foramen ovale, proved by contrast transesophageal echocardiography (TEE). Methods. One hundred one patients with stroke, in whom a patent RLS had been shown on contrast TEE, were investigated by TCDS of both middle cerebral arteries. Injection of 10 mL of agitated saline was applied without and subsequently with the Valsalva maneuver (VM) at the beginning of the contrast agent injection, and then 10 mL of a galactose‐based contrast agent was applied in the same protocol. Results. In all patients, cTCDS with the galactose contrast agent showed an RLS when performed with VM, but it showed an RLS in only 59 patients without VM. In contrast, saline showed an RLS in 54 patients with VM and in 20 patients without VM. The differences in diagnostic sensitivity were statistically significant (P < .001). Eighteen patients had only 1 microembolic signal (MES) after galactose injection, whereas others had more. The mean (SD) arrival times of the MES were 9 (6) seconds (range, 1–51 seconds) after galactose injection with VM and 9 (3) seconds (range, 2–20 seconds) after agitated saline with VM. The differences were not significant. Conclusions. Contrast TCDS with VM shows a TEE‐proven RLS with 100% sensitivity, but this was not true with galactose application without VM or agitated saline with or without VM. Therefore, use of the galactose contrast agent with VM is strongly recommended for detecting an RLS on TCDS. However, the arrival time and number of MESs detected need to be tested further.

Serial Transcranial Doppler Sonography in Ischemic Strokes in Middle Cerebral Artery Territory

The changes in middle cerebral artery (MCA) blood flow velocity were serially evaluated in 31 patients with acute ischemic strokes in the MCA territory using transcranial Doppler ultrasound. In patients with a poor clinical prognosis, MCA mean velocity on the infarcted side (MV,) was significantly decreased within 48 hours after onset, compared with that on the opposite side (MV2 ) (p < 0.01 ). However, this change was not significant in patients with a good clinical prognosis. As predictors of poor clinical prognosis, an MV, of 40 cm/sec or less and an asymmetry index of ‐ 20% or less showed positive predictive values of 93 and 88%, with sensitivities of 72 and 83% and specificities of 92 and 85%, respectively. An MV, slower than 20 cm/sec or an asymmetry index below ‐50% had a 100% positive predictive value and a 100% specificity, but less sensitivity (17 and 44%, respectively). Combining an MV, of 40 em/sec or less with an asymmetry index of ‐20% or less resulted in a 100% positive predictive value and a 100% specificity, with a relatively high sensitivity of 67%. As predictors of good clinical prognosis, an MV, faster than 40 cm/sec and an asymmetry index above ‐20% showed positive predictive values of 71 and 79%, with sensitivities of 92 and 85% and specificities of 72 and 83%, respectively. The clinical prognosis based on MV, seems particularly reliable for MCA territorial and cortical infarctions.

Improved Cerebral Vasoreactivity following Percutaneous Transluminal Angioplasty with Stenting of High-Grade Internal Carotid Artery Stenosis

Background: The aim of this study was to assess the effects of percutaneous transluminal angioplasty with stenting on cerebral vasoreactivity in carotid stenosis (CS). Methods: We studied the changes in the middle cerebral artery using transcranial Doppler and the breath-holding index (BHI) after hypercapnia in 33 patients with CS (15 symptomatic, 18 asymptomatic) before and 1 day and 1 month after stenting. Results: One day after stenting, the BHI significantly increased (p < 0.01) on the previously stenotic side in all patients. One month after stenting, the BHI was significantly higher on the contralateral side of asymptomatic (p < 0.05) and symptomatic patients (p < 0.01). Conclusion: Percutaneous transluminal angioplasty with stenting results in increasing improvement close to normalization of impaired cerebral vasoreactivity in patients with symptomatic and asymptomatic high-grade CS.

Ultrasonic Assessment of the Prevalence of Carotid Artery Stenosis in Asymptomatic Volunteers

High‐resolution Duplex scanning of the carotid artery was performed in 125 clinically asymptomatic and randomly chosen volunteers to determine the prevalence and extent of atherosclerotic stenosis. The proband age ranged from 24 to 74 years (mean, 50 years). Abnormal ultrasound findings were noted in 37 subjects (30%). Of this group, 34 had minimal carotid plaques causing less than 20% reduction in artery diameter and 3 had moderate plaques causing 20 to 49% reduction in diameter. No hemodynamically significant obstructions were noted. Stepwise logistic regression using age and sex as covariates identified age (p = 0.0002) and fibrinogen level (p = 0.02) as the most powerful predictors for the presence of asymptomatic carotid artery stenosis. The sonographic results of the asymptomatic group were compared with those in 200 patients (mean age, 55 years) who had acute ischemic stroke. Preliminary follow‐up results (mean follow‐up time, 26 months) in 38 probands of the asymptomatic group showed progression of the carotid stenosis in 13, which was associated with a significantly lower level of high‐density‐lipoprotein cholesterol.