Stroke In Middle Cerebral Artery Territory Research Articles

Abstract 90: Geometric Characteristics of Middle Cerebral Artery Atherosclerosis and Clinical Stroke

Objectives: We aimed to investigate the geometric characteristics of middle cerebral artery (MCA) atherosclerosis and their clinical relevance. Methods: Vessel wall magnetic resonance imaging was obtained in patients with recent stroke in MCA territory or suspected asymptomatic MCA atherosclerosis without cardioembolism or carotid artery stenosis. MCAs were classified as atherosclerotic or plaque-free based on whether plaque was present. Atherosclerotic MCAs were divided into MCAs with or without stroke. Geometric characteristics including M1 segment shape (Fig.1), plaque location, plaque length, plaque thickness, stenosis degree, and remodeling ratio were assessed. These geometric characteristics were compared between the groups. Results: A total of 1006 MCAs were analyzed, including 577 atherosclerotic MCAs (124 MCAs with stroke and 457 MCAs without stroke) and 429 plaque-free MCAs. Curvy MCAs were more prevalent than straight MCAs (79.2% vs 20.2%). The inferior-oriented M1 curve was the most prevalent (61.5%). In 90.4% of curvy atherosclerotic MCAs, the inner side of the M1 curve was involved by plaque. Only 9.6% of curvy atherosclerotic MCAs had no plaque involving the inner sides. Inferior and anterior plaque were found in 67.3% of atherosclerotic MCAs while superior and posterior plaque were found in 32.7%. The absence of an inferior-oriented M1 curve (OR 0.54, 95%CI 0.35-0.83), presence of superior plaque (OR 2.42, 95%CI 1.52-3.86), greater plaque length (OR 1.14, 95%CI 1.07-1.22), greater plaque thickness (OR 2.55, 95%CI 1.49-4.36), higher remodeling ratio (OR 1.15, 95%CI 1.04-1.27), and fewer quadrants involved by plaque (OR 0.68, 95%CI 0.51-0.91) were independently associated with MCAs with clinical stroke. Conclusions: MCA plaque tended to develop in the same orientation as the M1 inner curve. In addition, the inferior-oriented M1 curve was associated with MCAs without stroke, while superior plaque was associated with MCAs with stroke.

Does Diffusion Lesion Volume Above 70 mL Preclude Favorable Outcome Despite Post-Thrombolysis Recanalization?

Whether to withhold recanalization treatment when the diffusion-weighted imaging (DWI) lesion exceeds a given volume is unsettled. Our aim was to assess the impact of recanalization on outcome in patients with baseline DWI lesion ≥70 mL (DWI≥70 mL) treated ≤4.5 hours from onset. We hypothesized that recanalization is beneficial in a sizeable fraction of these patients and that this is associated with a larger DWI lesion reversal. We analyzed 267 consecutive patients treated with intravenous recombinant tissue-type plasminogen activator for middle cerebral artery territory stroke in whom an occlusion was present on magnetic resonance angiography and 24-hour recanalization and 90-day clinical outcome could be assessed. After stratification relative to the 70-mL DWI lesion cut point, we calculated the odds ratio for recanalization of the primary arterial occlusive lesion (AOL score ≥2) to predict favorable outcome (modified Rankin scale score ≤2). DWI lesion reversal was compared between recanalizers with DWI≥70 mL with favorable and unfavorable outcomes. Median (interquartile range) DWI lesion volume was 22 mL (10-60), and median onset time to imaging was 116 minutes (86-151). Twelve (22%) of the 54 patients with DWI≥70 mL experienced favorable outcome, of which 9 had recanalized. In patients with DWI≥70 mL, recanalization was significantly associated with favorable outcome after adjustment for age and National Institutes of Health Stroke Scale (odds ratio =4.72 [1.09-20.32]; P=0.0375). Among recanalizers with DWI≥70 mL, absolute and relative DWI reversal volumes were larger in those with favorable as compared with unfavorable outcome (18.8 mL [12.2-47.6] versus 8.5 mL [4.3-31.1]; P=0.17; and 19.6% [10.9-62.8] versus 8.7% [3.9-16.5], respectively; P=0.049). Patients with DWI lesion volume ≥70 mL can benefit from recanalization after intravenous recombinant tissue-type plasminogen activator. This may partly reflect a larger amount of DWI lesion reversal.

Abstract TP39: High Accuracy of Magnetic Resonance T2*- Weighted Sequences for Detection of Intracranial Arterial Thrombus

Introduction: Rapid detection and location of vessel occlusion are pivotal in the intra-arterial management of patients with acute stroke in the emergency room. MRI has demonstrated to detect intravascular thrombus but its accuracy compared to CT angiography has not been well established. Hypothesis: Our purpose is to determine the accuracy of 1.5 T MRI T2*-weighted (W) sequences compared to immediate CT angiography as the standard reference imaging modality, for detection of intra-arterial thrombus in patients with suspected acute MCA infarction. Methods: Consecutive patients with suspected middle cerebral artery (MCA) territory stroke were selected from 2008 to 2009. The inclusion criteria for the study subjects: CTA, T2*W sequences included on MRI protocol and restricted diffusion in MCA territory on DWI within 12 hrs of clinical onset. Two investigators reviewed DWI and T2*W sequences for the presence of infarction and thrombus. Intracranial internal carotid artery (ICA), M1 and M2 segments of the MCA were accessed. Consensus was reached with a third reviewer for data analyses. Accuracy, sensitivity, specificity, positive and negative predictive values (PPV/NPV) were calculated. Results: Fifty-one patients were included in the study, of which 40 patients had confirmed arterial thrombus and 11 patients had normal studies on CTA. Of the subjects with arterial occlusion on CTA, the mean time interval from stroke onset to CTA was 4.2 h +/- 2.3 h (range, 0.4-12h). The mean time interval from CTA to MRI was 29.5 min +/- 11.1 min. Twenty-six cases showed M1 thrombus on CTA, of these, 22 cases had corresponding thrombus and 4 cases had no abnormality in T2*W sequences on MRI. Nevertheless, 25 patients demonstrated no M1 thrombus, either on CTA or MRI. After statistical analyses, we observed an accuracy of 92%, sensitivity of 85%, specificity of 100%, PPV 100% and NPV of 86% for M1 occlusion. The Kappa obtained was 0.79. Conclusion: In conclusion, T2*W sequences demonstrated overall high accuracy and specificity for detection of arterial thrombus in the M1 segment of the MCA in patients with suspected acute MCA ischemic stroke.

Characteristics of dynamic cerebral autoregulation in cerebral small vessel disease: Diffuse and sustained.

Cerebral small vessel disease is a major cause of stroke and vascular dementia; however, the pathogenesis is largely unclear. In this study, we investigated the characteristics of the impairment of dynamic cerebral autoregulation (dCA) in lacunar infarction patients. Seventy-one lacunar infarction patients were enrolled in the study, including 46 unilateral middle cerebral artery (MCA) territory stroke patients and 25 unilateral posterior cerebral artery (PCA) territory stroke patients. Each group of patients was randomly divided into two subgroups. Group 1 underwent dCA assessments in the bilateral MCAs, and Group 2 underwent dCA assessments in the bilateral PCAs. All patients were followed up for 6 months. Transfer function analysis was applied to derive the autoregulatory parameters of gain and phase difference. In the unilateral MCA territory stroke patients, impairments of dCA were observed in both the MCAs and PCAs, and the same results were observed in the unilateral PCA territory stroke patients. These impairments remained unchanged during the 6-month follow-up. In lacunar infarction, which is most prevalent type of cerebral small vessel disease, though patients with unilateral MCA territory/PCA territory stroke, the impairments of dCA were global and sustained. This finding suggests that the physiological changes associated with lacunar infarction were diffuse.

Prominent Vessel Sign on Susceptibility-Weighted Imaging in Acute Stroke: Prediction of Infarct Growth and Clinical Outcome

Background and PurposePredicting the risk of further infarct growth in stroke patients is critical to therapeutic decision making. We aimed to predict early infarct growth and clinical outcome from prominent vessel sign (PVS) identified on the first susceptibility-weighted image (SWI) after acute stroke.Materials and MethodsTwenty-two patients with middle cerebral artery (MCA) infarction had diffusion-weighted imaging, SWI, MR angiography, and clinical evaluation using the National Institutes of Health Stroke Scale at 7–60 hours and 5–14 days after stroke onset. Late-stage clinical evaluation at 1 and 3 months used the modified Rankin Scale. The infarct area and growth were scored from 10 (none) to 0 (infarct or growth in all 10 zones) using the Alberta Stroke Program Early CT Score (ASPECTS) system.ResultsInfarct growth on the second MRI occurred in 13 of 15 patients with PVS on the first MRI and not in any patient without PVS (n=7; r=0.86, P<0.001). The extent of PVS was significantly correlated with infarct growth (r=0.82, P<0.001) and early-stage outcome (P=0.02). No between-group difference in late-stage clinical outcome was found.ConclusionPVS on the first SWI after acute MCA territory stroke is a useful predictor of early infarct growth. Extensive PVS within the large MCA territory is related to poor early-stage outcome and could be useful for clinical assessment of stroke.

Abstract W P47: Developing an Acute Lesion Atlas from Patients with Middle Cerebral Artery Stroke

Background and purpose: Chronic lesion locations are associated with neurologic outcomes. However, voxel-based acute infarct maps have not been used to predict long-term deficits and outcomes. The combination of ischemic lesion volume and location may aid in acute outcome prediction models. We evaluated the feasibility of voxel-based lesion mapping in acute ischemic stroke patients. Methods: In a retrospective study of patients with suspected middle cerebral artery (MCA) territory strokes, we identified acute infarcts on the diffusion-weight imaging (DWI; b=1000) sequences and confirmed them on the apparent diffusion coefficient (ADC) sequences using a semi-qualitative approach. Only patients with all three sequences available were included in the study. We then manually created a lesion map for each patient. Lesions were overlaid on T1-weighted images and transformed to standardized stereotactic space. We overlaid the volumetric lesion masks from all patients to create a composite acute lesion atlas. Results: Among 164 patients, 5 (3.1%) patients had no clear acute lesion and 9 (5.5%) had technical problems with normalization or overlaying, leaving 150 (91.5%) patients for analysis (mean age 66.1 years; 52.0% male; 66.7% white; median NIHSS scale 4). A composite acute lesion atlas was developed (Figure) with regions of high overlap easily visible, suggesting high statistical power for acute lesion-outcome prediction modeling. Conclusion: Acute ischemic lesions can be reliably mapped and used to create aggregated infarct atlases. The considerable overlapping regions in stroke patients might provide sufficient power to detect highly correlated lesion-outcome relationships. The proposed technique may provide a time-sensitive method for identifying acute infarct location, predicting the course of recovery, and selecting patients for early interventions.

Predicting Stroke Outcome Using Clinical- versus Imaging-based Scoring System

Several models to predict outcome in ischemic stroke patients receiving intravenous (i.v.) alteplase can be divided into clinical-based and imaging-based systems. Alberta Stroke Program Early Computed Tomography (CT) Score (ASPECTS) and Dense cerebral artery sign/early infarct signs on admission CT scan, prestroke modified Rankin Scale (mRS) score, Age, Glucose level at baseline, Onset-to-treatment time, and baseline National Institutes of Health Stroke Scale score (DRAGON) are typical imaging- and clinical-based scoring systems, respectively. Therefore, we compared predictability of stroke outcome of clinical (DRAGON)- and imaging (ASPECTS)-based scoring systems. We analyzed patients who were diagnosed with middle cerebral artery territory stroke and treated with i.v. alteplase at Gachon University Gil Hospital over 5 years and compared performance of 2 scoring systems for prediction of good functional outcome (mRS, 0-2) with Pearson correlation and area under the curve-receiver operating characteristic (AUC-ROC). In addition, we analyzed predicting power of several clinical factors and 2 scoring systems by multiple regression analysis. Study population (N = 120) had mean age of 66.2 ± 13.2 years. ASPECTS (r = -.841, P < .0001) and DRAGON (r = .657, P < .0001) were significantly correlated with good functional outcome. In addition, statistical comparisons suggested that ASPECTS (AUC-ROC, .972; 95% confidence interval [CI], .947-.996) is significantly superior to DRAGON (AUC-ROC, .854; 95% CI, .786-.922) in predicting functional outcome (difference between areas, .118 ± .0332; 95% CI, .0559-.180, P = .0002). Multiple regression analysis revealed that ASPECTS was the independent predictor of good prognosis (OR, 6.59 per 1-point increase; 95% CI, 2.35-18.49; P < .0001 and OR, 77.67 for ASPECTS ≥ 8; 95% CI, 14.30-421.79; P < .0001). ASPECTS is superior method for predicting functional outcome in acute ischemic stroke patients receiving i.v. alteplase compared with DRAGON and integration of ASPECTS score into clinical care pathway as decision-making tool can be reasonable.

Neuroimaging patterns of ischemic stroke after percutaneous coronary intervention

We sought to determine neuroimaging patterns, ischemic mechanisms, and functional outcomes of ischemic stroke related to percutaneous coronary intervention (PCI) over a 16-year period. Stroke is a feared complication of PCI, associated with poor patient outcomes. The majority of strokes that occur after PCI are ischemic rather than hemorrhagic. However, mechanisms of cerebral ischemia in this setting are incompletely understood. We performed a retrospective single-center cohort study of patients with radiologically confirmed ischemic stroke occurring after PCI (PCI-stroke), between January 1, 1994 and December 31, 2009. Using brain imaging, infarctions were subclassified by radiological pattern and arterial territory as embolic, small subcortical, or hemodynamic. Modified Rankin Scale scores were used to assess functional outcome at 3 and 6 months. Radiologically confirmed PCI-stroke was identified in 35 patients. The majority of strokes (91%) revealed an embolic pattern, while the remaining strokes were small subcortical infarctions (9%). Watershed strokes with exclusive borderzone involvement, indicative of a hemodynamic mechanism, were not identified, despite the presence of periprocedural hypotension in 23% of patients. The middle cerebral artery (MCA) territory was affected most frequently (80%), and all patients suffering a complete MCA territorial infarction (14%) died in the hospital. Functional outcome among survivors of PCI-stroke was typically favorable in those who had single rather than multiple vascular territory involvement. The vast majority of radiologically confirmed ischemic strokes related to PCI are embolic. MCA territory strokes are most common and uniformly fatal when the entire MCA territory is affected. Functional outcomes in survivors of PCI-stroke are improved when only a single arterial territory is affected.

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

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. 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. 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). 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.

Proximal hyperdense middle cerebral artery sign predicts poor response to thrombolysis.

The aim of our study was to compare the rapid neurological improvement after intravenous recombinant tissue-type plasminogen activator (rtPA) in patients with proximal hyperdense middle cerebral artery sign (p-HMCAS) to those without the sign and those with the distal hyperdense middle cerebral artery sign (d-HMCAS). Admission and 24 hour non-contrast CT scans of 120 patients with middle cerebral artery (MCA) territory stroke who were treated with intravenous rtPA were assessed for the presence of p-HMCAS and d-HMCAS. The sign was classified according to the site of occlusion. Rapid neurological improvement was defined as ≥50% improvement in the NIHSS score at 24 hours after thrombolysis. Rapid neurological recovery after thrombolysis was assessed and compared between the subgroups. Rapid neurological recovery was less common in the pooled group of patients with either p-HMCAS or d-HMCAS than those without the sign (p<0.01). Patients with p-HMCAS were less likely to have rapid neurological recovery than those with d-HMCAS (p<0.01). However, there was no difference in early neurological recovery between patients with d-HMCAS and those without any hyperdense sign. Our study showed that poor neurological recovery post rtPA was confined to p-HMCAS and not to d-HMCAS, indicating that these signs have quite different prognostic significance.

Dynamic cerebral autoregulation is heterogeneous in different subtypes of acute ischemic stroke (1068.5)

Dynamic cerebral autoregulation is heterogeneous in different subtypes of acute ischemic stroke Zhen‐Ni Guo1, Jia Liu2, Yingqi Xing1, Yi Yang1* 1Department of Neurology, the First Norman Bethune Hospital of Jilin University, Chang Chun, China; 2Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China; Zhen‐Ni Guo and Jia Liu contributed equally to the manuscript. * Correspondence author: Yi Yang1, M.D, PhD, #71 Xinmin Street, 130021, Changchun, China. Telephone: 86‐15843073217; E‐mail: doctor_yangyi@hotmail.com Dynamic cerebral autoregulation (dCA) is affected in acute ischemic stroke. Large‐artery atherosclerosis and small‐artery occlusion are considered as the most common subtypes. However, the underlying mechanisms might be heterogeneous, resulting in varied clinical conditions and outcomes. We therefore investigated the pattern of dCA in these two subtypes using transfer function analysis (TFA).Forty‐one patients with acute unilateral middle cerebral artery (MCA) territory stroke (15 with ipsilateral large‐artery atherosclerosis and 26 with small‐artery occlusion, according to TOAST classification) and 20 healthy volunteers were enrolled. Non‐invasive continuous CBFV and ABP were recorded simultaneously from each subject in supine position for 10 minutes using transcranial Doppler (TCD) on MCA bilaterally and servo‐controlled plethysmograph on the middle finger, respectively. TFA was applied to derive autoregulatory parameters, gain, phase, and slope of step response. The results showed that dCA is impaired ipsilaterally with the affected side in the large‐artery atherosclerosis group, whereas the impairment of dCA in the small‐artery occlusion group is bilateral.We thus concluded that dCA in different subtypes of acute ischemic stroke is heterogeneous, which might be attributed to the varied pathologic changes of vessels.

Dynamic Cerebral Autoregulation Is Heterogeneous in Different Subtypes of Acute Ischemic Stroke

Background and PurposeStroke of large-artery atherosclerosis and small-artery occlusion are two main subtypes of stroke according to TOAST classification. The underlying mechanisms of how these two subtypes affect dynamic cerebral autoregulation (dCA) might be heterogeneous, resulting in varied clinical conditions and outcomes. We therefore studied the pattern of dCA in these two subtypes.MethodsForty-one patients with acute unilateral middle cerebral artery (MCA) territory stroke (15 with ipsilateral large-artery atherosclerosis and 26 with small-artery occlusion) and 20 healthy volunteers were enrolled. Non-invasive continuous cerebral blood flow velocity and arterial blood pressure were recorded simultaneously from each subject in supine position using transcranial Doppler on MCA bilaterally and servo-controlled plethysmograph on the middle finger, respectively. Transfer function analysis was applied to derive autoregulatory parameters, gain, phase difference (PD), and slope of step response.ResultsIn the large-artery atherosclerosis group, PD in affected hemisphere was 42.9±18.5 degree, which is significantly lower than the unaffected hemisphere (72.4±29.9 degree, P<0.01), and the healthy group (P<0.01). However, PD is similar in the unaffected hemisphere and healthy group (P>0.1). In the small-artery occlusion group, PD in the affected hemisphere was similar to that in the contralateral hemisphere (33.8±17.9 vs. 32.6±21.1 degree, P>0.1), both sides were significantly lower than the healthy group (all P<0.001).The results of the slope of step response agree with the findings in PD.ConclusionsDCA in different subtypes of acute ischemic stroke is heterogeneous, which might be attributed to the varied pathologic changes of cerebral blood vessels.

Stroke in a Case of Neonatal Lupus

Stroke is an extremely rare complication of congenital heart block in children. We report a 2-year-old girl with congenital complete heart block who presented with acute-onset right middle cerebral artery territory stroke. The congenital heart block was secondary to maternal lupus.

A Prospective Study Evaluating the Clinical Profile of Pediatric Stroke in Western Rajasthan

Objective: To delineate the profile of pediatric patients with stroke in Western Rajasthan. Methods: This was a hospital based prospective follow-up study carried out over a period of one year. In the study all admitted patients (6 m-18 years old) fulfilling the both clinical and radiological criteria (CT Scan/MRI) for stroke were enrolled (n=50). Epidemiological profile, clinical parameters and complications of these 50 patients were analyzed. Results: 50 patients of stroke (as per case definition) were admitted in our institute over a period of one year out of which 64% were males (n= 32) and 36% were females(n=18) with a ratio of 1.78:1. 48% patients were in age group of 6 to 24 months (n=24); with a overall mean age of presentation of 52.8 ± 51.0 months. 74% (n=37) of the patients had Arterial Ischemic stroke (AIS); 8% (n=4) had Cerebral Sinus Venous Thrombosis (CSVT); 6% (n=3) had hemorrhagic stroke; 12% (n=6) had AIS coexisting with CSVT and hemorrhagic stroke. AIS was most commonly seen in age group of 6-24 months of age (45.95%); CSVT was most commonly seen among children of 60-120 months (50%); Combined type of stroke was seen only in patients between age group of 6-60 months. Anterior circulation was most common circulation involved in patients of stroke at all ages (63%), followed in frequency by combination of both anterior and posterior circulation (28.3%) and posterior circulation alone (8.7%). Involvement of both hemispheres of the brain together was slightly more common (36%) than either right side alone (34%) or left side alone (30%). Middle cerebral artery (MCA) territory stroke was the most common territory to be involved at all ages (45.6%). Isolated Posterior cerebral artery (PCA) & Internal carotid artery (ICA) territory stroke were more common (28.6%) in children >120 months. Involvement of more than one vessel territory was seen in children between 6-24 months (20.8%) and 24-60 months (44.4%) of age. Seizures were reported in 80% (n=40) of children amongst which 45% (n=18) had generalized seizures and 55% (n=22) had focal seizures. In patients with AIS, focal seizures were more common (54%) than generalized seizures. Patients who had CSVT type of stroke, only 50% patients had seizures. All hemorrhagic stroke patients presented with generalized seizure. Impairment of consciousness was seen in 50% of stroke patients. Consciousness was most commonly affected in patients of hemorrhagic stroke (100%). Co-morbid conditions were seen in 58% patients and Neurotuberculosis was the most common (22%) co-morbid condition associated with patients of stroke. Hemiparesis was the most common (66%) mode of presentation followed by facial palsy (26%). 26% (n=13) patients of stroke had no neurological deficit at the time of discharge and 36% (n=18) patients had mild to moderate neurological deficit, 30% (n=15) had severe deficit and 8% (n=4) patients expired. Conclusion: Thus stroke in childhood is an important issue to be addressed as it is not uncommon as previously thought and is an important cause of morbidity and mortality. Despite excellent advances in clinical care and increasing availability of infrastructure, newer medicines and technology, the exact clinic-epidemiologic profile of both adult and pediatric stroke in Western Rajasthan is still not available. The current study has therefore been designed to evaluate the clinic-radiologic profile of pediatric stroke and to see whether stroke profile, mode of presentation and outcome of

Percutaneous endoscopic gastrostomy tube placement in left versus right middle cerebral artery stroke: Effects of laterality

Prolonged dysphagia after middle cerebral artery (MCA) territory strokes may require percutaneous endoscopic gastrostomy (PEG) tube feeding. We examined the predictors of PEG placement among patients with MCA stroke. It was hypothesized that stroke laterality was a predictor. A retrospective cohort study of existing data from Hartford Hospital Stroke Database was done. A total of 157 patients with acute ischemic MCA stroke were included. Patients were divided into the "PEG" group (n = 24) and "no PEG" group (n = 133). Existing demographic, clinical and swallowing data were compared between the 2 groups. Demographic data were similar between the groups. The "PEG" group had a higher admission National Institute of Health Stroke Scale (NIHSS) score, higher proportion of patients who had thrombolytic administration, in- hospital aspiration pneumonia and inability to be assessed on first swallow evaluation. Multivariate analysis revealed that all, except thrombolytic administration may predict PEG placement. Admission NIHSS score, in-hospital aspiration pneumonia and inability to undergo first swallow evaluation may predict PEG placement in patients with acute MCA stroke. Stroke laterality was not associated. This knowledge facilitates early identification of patients that may require PEG tube placement for early nutrition provision and discharge to rehabilitation.

Effect of Middle Cerebral Artery Territory Ischemic Stroke on QT Interval

Prolonged QT interval associates with increased risk for sudden cardiac death after acute ischemic stroke. However, pathophysiology of prolonged QT interval after stroke is poorly elucidated. In this study, we investigated whether QT interval dynamics is different in patients with right and left middle cerebral artery (MCA) territory stroke. Electrocardiogram (ECG) intervals were compared between baseline (retrieved retrospectively from medical records) and admission (acquired at the acute hospital admission) in 33 patients (65 ± 9.5 years) with right or left MCA territory ischemic stroke. Head computed tomography (CT), cardiac ultrasound, and cardiac CT scans were undertaken. Stroke was located in the right MCA territory in 21 (64%) and in the left MCA territory in 12 (36%) patients. Patients with right and left MCA stroke were similar with respect to time interval between baseline and admission ECG recordings, positive history of heart disease, and left ventricular dimensions. Increase in heart rate-corrected QT interval (QTc) from baseline to admission was demonstrated to occur more often in patients with right (16 of 21; 76%) than in patients with left (3 of 12; 25%; P < .01) MCA stroke. ΔQTc between baseline and admission was significantly longer in patients with right (23 ± 23 milliseconds) than in patients with left (-11 ± 19 milliseconds; P < .0001) MCA stroke. Percent ΔQTc between baseline and admission was longer in patients with right (5.5% ± 5.5%) than in patients with left (-2.6% ± 4.7%; P < .001) MCA stroke. Right MCA ischemic stroke results in prolongation of QT interval. Findings indicate cerebral asymmetry in brain-heart interaction during acute ischemic stroke.

The complexities of acute stroke decision-making

We hypothesized that low rates of tissue plasminogen activator (tPA) use are only partially explained by medical considerations, and that biases, beliefs, systems, and uncertainty affect acute stroke decision-making. We generated a list of factors potentially influential in acute stroke decision-making: uncertainty, patient demographics that may predispose to bias (age, sex, comorbidities), physician experiences and beliefs, and systems factors. An online survey was distributed to neurologists in the province of Ontario, Canada, to assess the influence of these elements. A response rate of 69% was achieved. Seventy-nine percent (79%) of respondents were less likely to administer IV tPA to patients with dementia, and many were less likely to treat patients from nursing homes, with more severe strokes, or over age 80. All respondents recognized the presence of diagnostic uncertainty, and 87% believed that uncertainty in interpreting advanced imaging affected their use of tPA. The majority of respondents (70%) believed that a large left middle cerebral artery territory stroke was a fate worse than death. Four percent did not believe that IV tPA is an effective treatment for stroke. This study provides evidence for the presence of uncertainty, beliefs, and biases in acute stroke decision-making. This survey should be considered a preliminary investigation of the multiple factors implicit in IV tPA administration.

Stylet-Assisted Tracheal Intubation Through an ILMA in a Patient with an Anterior Larynx

To the Editor Although the intubating laryngeal mask airway (ILMA) has been described for use in morbidly obese patients,1 despite its correct placement, tracheal intubation may be unsuccessful. An obese male patient (body mass index [BMI] = 34) in the intensive care unit with a right middle cerebral artery territory stroke required urgent tracheal intubation owing to poor Glasgow coma scale (E1V1M2). After sedation and paralysis, ventilation via a mask was adequate but intubation using a #4 Macintosh blade, external laryngeal manipulation, and a bougie was not possible. An ILMA (#4 LMA-Fastrach™, The Laryngeal Mask Company Limited, Le Rocher, Victoria, Mahé, Seychelles) was placed and ventilation resumed. Tracheal intubation using the flexometallic tube provided with the ILMA failed as the tube tip was repeatedly displaced into the esophagus. Repositioning of the ILMA and Chandy's maneuver part 22 were attempted but also unsuccessful. Intubation with a 7.0-mm internal diameter cuffed Portex polyvinyl chloride (PVC) endotracheal tube (ETT) (Smiths Medical, UK), together with a flexion maneuver, also did not help because of the anteriorly positioned larynx. Size 5 ILMA and Fiberoptic Bronchoscope were unavailable. Hence, using a stylet, the tip of the portex tube was bent as shown in Figure 1 and reintroduced through ILMA, and the ETT could be easily advanced off the stylet into the trachea.Figure 1: Angle of emergence formed by the tracheal tubes on emerging from the distal aperture of the intubating laryngeal mask airway (ILMA). A, LMA-Fastrach silicone wire-reinforced tube (7.5-mm internal diameter). B, Portex polyvinyl chloride tracheal tube (7.5-mm internal diameter). C, Portex polyvinyl chloride tracheal tube with stylet (PVCT; 7.5-mm internal diameter).In cases of extremely anterior larynx, accentuating the angle of emergence of the tracheal tube from the ILMA may facilitate intubation.3 This may be safely done by ensuring that the tip of the stylet remains within the ETT, about 1 to 2 cm proximal to the tip of ETT. We measured the angle of emergence (using a protractor) of Flexometallic and Portex PVC ETT through ILMA and found them to be 35° and 45°, respectively (Fig. 1A & 1B). Introducing a stylette as suggested increases the angle of emergence to 65° (Fig. 1C), which aids in placement of the tracheal tube tip through ILMA in patients with anterior larynx. Damage to the arytenoids and trachea is a potential complication of blind intubation. Difficulty in advancing the tube due to impingement upon the anterior surface of the larynx is another possibility. Using the Parker flexitip PVC tube is an option in this scenario. The centered, tapered, and flexible distal tip gently flexes when resistance is encountered, thus enabling successful introduction minimizing airway trauma.4 Patient consent statement Written permission from the patient's first degree relative was obtained because the patient passed away at home owing to unrelated causes, months after treatment, prior to this submission. The written consent statement is available from the archival author. Georgene Singh, MD Appavoo Arulvelan, MD Kadarapura N. Gopalakrishna, MD Sethuraman Manikandan, MD Vimala Smita, MD, DM Ramesh C. Rathod, MD Department of Anesthesiology Sree Chitra Tirunal Institute for Medical Sciences and Technology Thiruvananthapuram Kerala, South India [email protected]

Association between ABCD2 Score, Cerebral Vascular Territory, and Dyslipidemia in Patients with Transient Ischemic Attack (Our Bulgarian Experience)

Transient ischemic attack (TIA), defined as an ‘acute cerebrovascular incident requiring emergency’, is usually assessed based on the association of the age, blood pressure, clinical features, duration of symptoms, and diabetes (ABCD2) score (1,2). Some studies have demonstrated that patients with vertebrobasilar TIA have higher short-term and an identical long-term risk for stroke compared with those with hemispheric TIA (3). Also, patients with left hemispheric stroke are more often treated in the hospital than patients with right hemispheric stroke (4,5). We reported our Bulgarian experience and suggested that risk stratification and stroke frequency in first registered TIA patients with moderate risk (ABCD2 5) are associated with initially affected cerebral vascular territory and presence of modifiable risk factors. One hundred thirty consecutive TIA patients, with clinical symptoms lasting up to 60 mins were followed-up for 18 months between November 2008 and April 2010. Among them, mean age was 70·68 8·82 years and 61 (46·9%) were males. Hypertension was present in 99 (76·2%) patients, diabetes mellitus in 33 (25·4%), 36 (27·7%) had heart rhythm and conduction disorders, 53 (40·8%) were dyslipidemic, and 78 (60·0%) were smokers. Diagnosis was confirmed by neurological examinations and normal computed tomography/magnetic resonance imaging results. The ABCD2 scores were between 4 (46·2%) and 5 (53·8%). The right middle cerebral artery (MCA) was involved in 43 of the patients, the vertebrobasilar system in 46, and the left MCA in 41. Within the first three-months, strokes occurred in eight patients, and the stroke frequency was higher in patients with TIA in the right MCA and in the vertebrobasilar system. Over the 12-month period, strokes developed in 23 patients with presence of dyslipidemia in almost all cases (odds ratio: 24·61, 95% confidence interval: 5·45, 111·21). Data analysis indicated statistically significant differences between the identified cerebral vascular territories: right MCA (47·8%), vertebrobasilar system (30·4%), and left MCA (21·7%) with the higher incidence of stroke in the right MCA territory, involved initially (Fig. 1). Dimitar Maslarov* and Desislava Drenska

Early infarct growth predicts long-term clinical outcome after thrombolysis

BackgroundIschemic lesion growth may be a surrogate marker of clinical outcome, but no such interrelationship after thrombolysis has yet been determined. We evaluated the association between early infarct growth on diffusion-weighted imaging (DWI) and long-term clinical outcome after thrombolysis. MethodsWe retrospectively reviewed outcomes in patients with acute middle cerebral artery territory stroke who had been treated with intravenous tissue plasminogen activator or intra-arterial urokinase. DWI lesion volumes were measured at baseline and within 7days, and the difference was calculated. Clinical outcome was evaluated using the modified Rankin Scale (mRS) at 3months. Good and poor clinical outcomes were defined as: a) mRS 0–1 vs. mRS 2–6, b) mRS 0–2 vs. mRS 3–6, and c) responder analysis which was influenced by the baseline National Institutes of Health Stroke Scale (NIHSS) scores: good and poor outcomes were defined as mRS 0 vs. mRS 1–6 if the baseline NIHSS score was <8, mRS 0–1 vs. mRS 2–6 if the NIHSS score was 8–14, and mRS 0–2 vs. mRS 3–6 if the NIHSS score was >14. The relationship between the ischemic lesion volume change and clinical outcome was explored. The cut-off value of infarct growth predicting long-term outcome was estimated using receiver operating characteristic analysis. ResultsOf the 81 patients included, 67 (82.7%) showed lesion growth, and absolute growth was significantly related to poor outcomes (P<0.001 all for mRS 2–6, mRS 3–6, and responder analysis). Multivariate analysis showed that absolute lesion growth was an independent predictor of poor outcome, defined as mRS 2–6 (P=0.002; odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02–1.10), mRS 3–6 (P=0.001; OR, 1.06; 95% CI, 1.02–1.10), and poor outcome by responder analysis (P=0.001; OR, 1.06; 95% CI, 1.03–1.10). The cut-off values of lesion growth that discriminated between good and poor outcomes were 14.11cm3 for mRS 2–6; 15.87cm3 for mRS 3–6; and 14.11cm3 in responder analysis. ConclusionsEarly DWI lesion growth is an independent predictor of poor outcome after thrombolysis and may serve a potential surrogate marker of clinical outcome in acute stroke trials.