Hemodynamic Factors and Perfusion Abnormalities in Early Neurological Deterioration

Hearing loss is associated with increased stroke risk in the Dongfeng-Tongji Cohort

BACKGROUND AND AIMS

The evidence concerning the association between hearing loss and stroke is limited. We aimed to investigate the association of hearing loss with risk of stroke and its subtypes among the middle-aged and older Chinese population.

METHODS

We included 19,238 participants aged 64.6 years from the Dongfeng-Tongji Cohort in 2013. Hearing loss was classified into normal, mild, moderate, severe or greater levels by the pure tone average at speech frequency and high frequency, respectively. We calculated the odds ratios of hearing loss and stroke by logistic regression models.

RESULTS

With the increase of hearing loss level, the prevalence risk of stroke has gradually increased. Compared with normal hearing, participants having severe or greater hearing loss had a higher stroke risk of 76% and 39% at speech frequency and at high frequency, respectively. Similarly, individuals with severe or greater hearing loss had an increased risk of ischemic stroke of 69% and 52% at speech frequency and high frequency, respectively; while severe or greater hearing loss was associated with about a 2-fold risk of hemorrhagic stroke than normal hearing only at speech frequency. Stratified analysis suggested that some high cardiovascular risk participants such as male, age ≥65, exposed to occupational noise, smoker and with diabetes, hypertension or hyperlipidemia had higher risk of stroke. Furthermore, severe or greater hearing loss combined with age, diabetes, hypertension and hyperlipidemia had joint effects on stroke.

CONCLUSIONS

The results have suggested a dose-response relationship between hearing loss and stroke risk in middle-aged and older adults.

Temporal changes in the neutrophil to lymphocyte ratio and the neurological progression in cryptogenic stroke with active cancer

Background

Ischemic stroke patients with active cancer frequently experience early neurological deterioration (END); however, the predictors of END are not well studied. The neutrophil to lymphocyte ratio (NLR) has recently been described as a predictor of poor outcomes in cancer and stroke. However, its role in cancer-related stroke has not been addressed.

Aim

We aimed to evaluate the association between the NLR and END in cancer-related stroke patients.

Methods

We included 85 cryptogenic stroke patients with active cancer. END was defined as an increase ≥ 4 on the total National Institutes of Health Stroke Scale (NIHSS) score within 72 hours of admission. The NLR was calculated as the ratio of the absolute neutrophil count to the absolute lymphocyte count. We obtained the NLR during the following three periods: at admission, 1–3 days after admission (D 1–3 NLR) and 4–7 days after admission (D 4–7 NLR).

Results

END occurred in 15 (18%) of the 85 patients. END was significantly associated with the initial NIHSS score, infarction volume, and the D 1–3 NLR. In multivariate analysis, a higher D 1–3 NLR, measured before END events, remained an independent predictor of END [adjusted odds ratio = 2.78, 95% confidence interval = 1.09–7.08, P = 0.032]. In terms of temporal changes in the NLR, the END group showed a tendency toward temporal increase in the NLR at D 1–3 (P = 0.061) with subsequent decrements in the D 4–7 NLR (P = 0.088), while the non-END group showed no significant changes in the NLR between periods.

Conclusions

This study demonstrated that a higher NLR could predict END events in cryptogenic stroke patients with active cancer. However, the results should be confirmed in further large prospective studies.

Decline in Hemoglobin during Hospitalization May Be Associated with Poor Outcome in Acute Stroke Patients

BACKGROUND AND PURPOSE

Anemia upon hospital admission is a known predictor of poor functional outcomes in patients with acute cerebral infarction. However, it remains unclear whether reductions in hemoglobin levels during hospitalization influence stroke outcomes. We investigated the association between in-hospital decline in hemoglobin and poor outcomes.

MATERIALS AND METHODS

We retrospectively analyzed data from 480 consecutive patients who had experienced acute cerebral infarction and presented without anemia between January 2012 and March 2015. Decline in hemoglobin was taken as the difference between hemoglobin levels upon admission and nadir hemoglobin. Poor outcome was defined as a modified Rankin Scale score 3-6. A multivariate analysis of the relationship between decline in hemoglobin and poor outcome at discharge was conducted for various patient characteristics.

RESULTS

The mean hemoglobin level at admission was 14.3 ± 1.3 g/dL, whereas the mean nadir hemoglobin value was 13.1 ± 1.9 g/dL, with a mean decline in hemoglobin of 1.3 ± 1.5 g/dL. In patients with poor outcomes, mean decline in hemoglobin was significantly reduced to 3.1 g/dL (P < .001). The optimal cutoff decline in hemoglobin required to distinguish a poor outcome was 1.5 g/dL whereas the sensitivity and specificity were 62% and 82.3%, respectively, with an area under the curve of .77 (P < .0001). A decline in hemoglobin below 1.5 g/dL was found to be an independent predictor of poor outcome (odds ratio: 2.10; confidence interval: 1.10-3.99; P = .023).

CONCLUSION

Decline in hemoglobin in patients hospitalized with acute stroke may be associated with poor outcome.

Collateral response modulates the time–penumbra relationship in proximal arterial occlusions

Objective

While clinical benefit from thrombolysis decreases with increase in time from stroke onset, the relationship of acute physiologic tissue compartments and collateral response to stroke onset time remains unclear.

Methods

We studied consecutive patients with proximal arterial occlusions (n = 355) with whole-brain perfusion CT with CT angiography within 6 hours of stroke onset. Penumbra and core were defined using voxel-based thresholds. Tissue mismatch was defined as the ratio of penumbra to core. Collateral scores were assessed using a previously validated visual score.

Results

Mean (SD) age was 72.1 (12.4) years, median (interquartile range) NIH Stroke Scale score 16 (4), mean (SD) time to imaging 152.5 (69.7) minutes. Penumbra volume (Spearman ρ = 0.119,p= 0.026) and mismatch increased (Spearman ρ = 0.115,p= 0.030) with time from onset. Core volume decreased (Spearman ρ = −0.112,p= 0.035) while collateral scores increased with time (Spearman ρ = 0.117,p= 0.028). On multivariable regression, good collateral scores predicted longer time since onset (β = 0.101,p= 0.039) while mismatch was not a predictor (β = 0.001,p= 0.351). Good collateral score was the strongest independent predictor of final infarct volume and improvement in clinical deficit.

Conclusions

In our large patient cohort study of proximal arterial occlusions, we found an incremental collateral response and preserved penumbral volume with time. Thus, tissue viability can be maintained in this time window (0–6 hours) after stroke if leptomeningeal collaterals are able to sustain the penumbra. Our findings suggest that a longer therapeutic window may exist for intra-arterial intervention and that multimodal imaging may have a role in strokes of unknown onset time.

Minor stroke due to large artery occlusion. When is intravenous thrombolysis not enough? Results from the SITS International Stroke Thrombolysis Register

Purpose

Beyond intravenous thrombolysis, evidence is lacking on acute treatment of minor stroke caused by large artery occlusion. To identify candidates for additional endovascular therapy, we aimed to determine the frequency of non-haemorrhagic early neurological deterioration in patients with intravenous thrombolysis-treated minor stroke caused by occlusion of large proximal and distal cerebral arteries. Secondary aims were to establish risk factors for non-haemorrhagic early neurological deterioration and report three-month outcomes in patients with and without non-haemorrhagic early neurological deterioration.

Method

We analysed data from the SITS International Stroke Thrombolysis Register on 2553 patients with intravenous thrombolysis-treated minor stroke (NIH Stroke Scale scores 0-5) and available arterial occlusion data. Non-haemorrhagic early neurological deterioration was defined as an increase in NIH Stroke Scale score ≥4 at 24 h, without parenchymal hematoma on follow-up imaging within 22-36 h.

Findings

The highest frequency of non-haemorrhagic early neurological deterioration was seen in 30% of patients with terminal internal carotid artery or tandem occlusions (internal carotid artery + middle cerebral artery) (adjusted odds ratio: 10.3 (95% CI 4.3-24.9), p < 0.001) and 17% in extracranial carotid occlusions (adjusted odds ratio 4.3 (2.5-7.7), p < 0.001) versus 3.1% in those with no occlusion. Proximal middle cerebral artery-M1 occlusions had non-haemorrhagic early neurological deterioration in 9% (adjusted odds ratio 2.1 (0.97-4.4), p = 0.06). Among patients with any occlusion and non-haemorrhagic early neurological deterioration, 77% were dead or dependent at three months.

Conclusions

Patients with minor stroke caused by internal carotid artery occlusion, with or without tandem middle cerebral artery involvement, are at high risk of disabling deterioration, despite intravenous thrombolysis treatment. Acute vessel imaging contributes usefully even in minor stroke to identify and consider endovascular treatment, or intensive monitoring at a comprehensive stroke centre, for patients at high risk of neurological deterioration.

Nocturnal Desaturation is Associated With Neurological Deterioration Following Ischemic Stroke: A Retrospective Observational Study

STUDY OBJECTIVES

The mechanism of early neurological deterioration (END) in patients with stroke remains unclear. We assessed the relationship between nocturnal oxygen desaturation (NOD) in the stroke unit (SU) and END, especially occurring at nighttime, following acute stroke.

METHODS

A retrospective analysis was performed on a total of 276 patients with ischemic stroke who were admitted to the SU between July 2013 and June 2015. The oxygen desaturation index was calculated from pulse oximetry data sampled every 1 minute during 9 hours on the first night (10:00 PM to 7:00 AM) after admission, and NOD was defined as oxygen desaturation index ≥ 5 events/h. END was defined as an increase of ≥ 2 points from the baseline National Institutes of Health Stroke Scale during 7 days after onset. We compared clinical characteristics and NOD between patients with and without END.

RESULTS

Among the included patients (mean age 69.2; male 55.4%), 42 patients (15.2%) experienced END. The proportion of NOD was significantly greater in the END group (45.2% versus 12.8%, P < .001). After adjusting for confounders, NOD was independently associated with END (odds ratio 7.57; 95% confidence interval 3.14-18.27). Among END patients, 47.6% patients (n = 20) had END during nighttime. Moreover, NOD was more frequent in patients with END during nighttime compared to those with END during daytime (73.7% versus 26.1%, P = .002).

CONCLUSIONS

NOD in the SU was associated with END, especially during nighttime, after ischemic stroke. This suggests that treatment of sleep-disordered breathing could be a modifiable factor to possibly reduce the risk of neurological worsening among acute stroke patients.

A randomized controlled study of intravenous fluid in acute ischemic stroke

OBJECTIVE

To compare the outcome of patients with acute ischemic stroke who received or did not receive intravenous fluid.

PATIENTS AND METHODS

This study was a prospective, multicenter, randomized, open-label trial with blinded outcome assessment. We enrolled acute ischemic stroke patients without dehydration aged between 18 and 85 years with NIH Stroke Scale score (NIHSS) score from 1 to 18 who presented within 72h after onset. Patients were randomly assigned to receive 0.9% NaCl solution 100ml/h for 3days or no intravenous fluid.

RESULTS

On the interim unblinded analysis of the safety data, significant excess early neurological deterioration was observed among patients in the non-intravenous fluid group. Therefore, the study was prematurely discontinued after enrollment of 120 patients, mean age 60 years, 56.6% male. Early neurological deterioration (increased NIHSS ≥3 over 72h) not of metabolic or hemorrhagic origin was observed in 15% of the non-IV fluid group and 3.3% of the IV fluid group (p=0.02). Predictors of neurological deterioration were higher NIHSS score, higher plasma glucose, and increased pulse rate. There was no difference in the primary efficacy outcome, NIHSS≤4 at day 7, 83.3% vs 86.7%, p=0.61 or secondary efficacy outcomes.

CONCLUSION

Administration of 0.9% NaCl 100ml/h for 72h in patients with acute ischemic stroke is safe and may be associated with a reduced risk of neurological deterioration. These study findings support the use of intravenous fluid in acute ischemic stroke patients with NIHSS less than 18 who have no contraindications.

Urine-Specific Gravity-Based Hydration Prevents Stroke in Evolution in Patients with Acute Ischemic Stroke

BACKGROUND

Early neurological deterioration after ischemic stroke (stroke-in-evolution [SIE]) is associated with poorer outcomes. Previous studies have demonstrated a link between hydration status and the development of SIE. In this study, we tested the hypothesis that rehydration therapy, administered on the basis of urine-specific gravity (USG) findings, might reduce the development of SIE.

METHODS

We conducted a single-arm prospective study of patients with acute ischemic stroke with historical controls. For the study group, a USG higher than 1.010 was taken as an indication for rehydration. Control group patients were rehydrated without referring to USG. An increase in National Institutes of Health Stroke Scale (NIHSS) score of 4 or higher within 3 days was defined as having SIE.

RESULTS

A total of 445 patients were analyzed, 167 in the study group and 278 in the control group. The proportion of patients who developed SIE was numerically, but not significantly, lower in the study group (5.9%; 10 of 167) compared with the control group (11.5%; 32 of 278). Among patients with a USG higher than 1.010 at admission, the SIE rate was significantly reduced in the study group compared with the control group (6.1% versus 16.0%; P = .021), while the rate of SIE was similar in those with a USG of 1.010 or lower at admission. Multivariate logistic regression analysis confirmed that USG-based hydration was an independent factor associated with reducing SIE.

CONCLUSIONS

USG might be a convenient and useful method for guiding fluid therapy in patients with acute ischemic stroke. USG-based hydration reduced the incidence of SIE among patients with a USG higher than 1.010 at admission.

Utility of digital subtraction angiography-based collateral evaluation in medically treated acute symptomatic basilar artery stenosis

BACKGROUND AND PURPOSE

Although a stroke from atherosclerosis in the basilar artery (BA) often presents with mild initial stroke severity, it has heterogeneous clinical courses. We investigated the efficacy of digital subtraction angiography (DSA)-based collateral perfusion evaluation in association with long-term outcomes of medically treated symptomatic basilar artery stenosis.

METHODS

From a registry database of all consecutive patients with stroke, we included 98 medically treated patients (due to mild initial stroke severity) [National Institute of Health Stroke Scale (NIHSS) scores ≤ 4; symptomatic basilar artery stenosis, 70-99%] with available initial diagnostic DSA. Basilar collateral scoring was performed via the DSA, using a modified version of the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology grading system in both the superior cerebellar artery and anterior/posterior-inferior cerebellar artery territories (score 0-8). The outcomes were designated as the 90-day modified Rankin Scale (mRS90) score (poor, 3-6). Student's t-test, chi-square test and logistic regression analyses were used to identify factors associated with a poor outcome.

RESULTS

The median initial NIHSS score was 2 [interquartile range (IQR), 0-3], median posterior circulation Alberta Stroke Program Early CT Score was 8 (IQR, 7-10), median collateral score was 7 (IQR, 7-8) and 20 (20.4%) had poor mRS90 scores. In multivariate analysis, poorer collateral scores (P = 0.003), higher NIHSS scores (P = 0.005) and lower posterior circulation Alberta Stroke Program Early CT Score (P = 0.017) were independently associated with a poor mRS90 score.

CONCLUSIONS

The DSA-based collateral scoring of the BA large branches might predict long-term outcome in medically treated symptomatic basilar artery stenosis with mild initial severity. Evaluation of BA collateral perfusion status might be useful to determine appropriate treatment strategies.

Heads Up! A Novel Provocative Maneuver to Guide Acute Ischemic Stroke Management

BACKGROUND

A common dilemma in acute ischemic stroke management is whether to pursue recanalization therapy in patients with large vessel occlusions but minimal neurologic deficits. We describe and report preliminary experience with a provocative maneuver, i.e. 90-degree elevation of the head of bed for 30 min, which stresses collaterals and facilitates decision-making.

METHODS

A prospective cohort study of <7.5 h of acute anterior circulation territory ischemia patients with minimal deficits despite middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive disease.

RESULTS

Five patients met the study entry criteria. Their mean age was 78.4 years (range 65-93). All presented with substantial deficits (median NIHSS score 11, range 5-22), but improved while in supine position during initial imaging to normal or near-normal (NIHSS score 0-2). MRA showed persistent M1 MCA occlusions in 4, critical ICA stenosis or occlusion in 1, and substantial perfusion-diffusion mismatch in all. To evaluate the potential for eventual collateral failure, patients were placed in a head of bed upright posture. Mean arterial pressure and heart rate were unchanged. Two showed no neurologic worsening and were treated with supportive care with excellent final outcome. Three showed worsening, including recurrent hemiparesis and aphasia at the 6th, recurrent aphasia at the 23rd, and recurrent hemineglect at the 15th upright minute. These 3 underwent endovascular recanalization therapies with successful reperfusion and excellent final outcome.

CONCLUSION

The 'Heads Up' test may be a useful, simple maneuver to assess the risk of collateral failure and guide the decision to pursue recanalization therapy in acute cerebral ischemia patients with minimal deficits despite persisting large cerebral artery occlusion.

Early neurological stability predicts adverse outcome after acute ischemic stroke

Background Deterioration in the National Institutes of Health Stroke Scale (NIHSS) in the early days after stroke is associated with progressive infarction, brain edema, and/or hemorrhage, leading to worse outcome. Aims We sought to determine whether a stable NIHSS score represents an adverse or favorable course. Methods Brain magnetic resonance images from a research cohort of acute ischemic stroke patients were analyzed. Using NIHSS scores at baseline and follow-up (day 3-5), patients were categorized into early neurological deterioration (ΔNIHSS ≥ 4), early neurological recovery (ΔNIHSS ≤ -4) or early neurological stability (ΔNIHSS between -3 and 3). The association between these categories and volume of infarct growth, volume of swelling, parenchymal hemorrhage, and 3-month modified Rankin Scale score were evaluated. Results Patients with early neurological deterioration or early neurological stability were less likely to be independent (modified Rankin Scale = 0-2) at 3 months compared to those with early neurological recovery ( P < 0.001). Patients with early neurological deterioration or early neurological stability were observed to have significantly greater infarct growth and swelling volumes than those with early neurological recovery ( P = 0.03; P < 0.001, respectively). Brain edema was more common than the other imaging markers investigated and was independently associated with a stable or worsening NIHSS score after adjustment for age, baseline stroke volume, infarct growth volume, presence of parenchymal hemorrhage, and reperfusion ( P < 0.0001). Conclusions Stable NIHSS score in the subacute period after ischemic stroke may not be benign and is associated with tissue injury, including infarct growth and brain edema. Early improvement is considerably more likely to occur in the absence of these factors.

Perfusion-Weighted MRI Parameters for Prediction of Early Progressive Infarction in Middle Cerebral Artery Occlusion

Objective

Early progressive infarction (EPI) is frequently observed and related to poor functional outcome in patients with middle cerebral artery (MCA) infarction caused by MCA occlusion. We evaluated the perfusion parameters of magnetic resonance imaging (MRI) as a predictor of EPI.

Methods

We retrospectively analyzed patients with acute MCA territory infarction caused by MCA occlusion. EPI was defined as a National Institutes of Health Stroke Scale increment ≥2 points during 24 hours despite receiving standard treatment. Regional parameter ratios, such as cerebral blood flow and volume (rCBV) ratio (ipsilateral value/contralateral value) on perfusion MRI were analyzed to investigate the association with EPI.

Results

Sixty-four patients were enrolled in total. EPI was present in 18 (28%) subjects and all EPI occurred within 3 days after hospitalization. Diabetes mellitus, rCBV ratio and regional time to peak (rTTP) ratio showed statically significant differences in both groups. Multi-variate analysis indicated that history of diabetes mellitus [odds ratio (OR), 6.13; 95% confidence interval (CI), 1.55–24.24] and a low rCBV ratio (rCBV, <0.85; OR, 6.57; 95% CI, 1.4–30.27) was significantly correlated with EPI.

Conclusion

The incidence of EPI is considerable in patients with acute MCA territory infarction caused by MCA occlusion. We suggest that rCBV ratio is a useful neuro-imaging parameter to predict EPI.

Antiplatelet drug resistance is associated with early neurological deterioration in acute minor ischemic stroke in the Chinese population

To evaluate the prevalence and risk factors of antiplatelet drug resistance and its association with early neurological deterioration (END) and recurrent ischemic stroke (RIS) in patients with acute minor stroke. Antiplatelet drug resistance was assessed by platelet aggregation assay in 426 patients with minor stroke who were receiving combined treatment of aspirin and clopidogrel. All patients were followed up for 90 days. The primary endpoint of the study was END within 10 days after admission. The secondary endpoints included RIS, myocardial infarction and death during 90 days of treatment. The safety endpoints were intracerebral or extracranial hemorrhagic events. Cox proportional hazard regression analysis was performed to determine the risk factors for the primary endpoint and secondary endpoints. Among the 426 patients, 24.4 % exhibited aspirin resistance, 35.9 % exhibited clopidogrel resistance, and 19.2 % displayed concomitant aspirin and clopidogrel resistance. In multivariate analysis, diabetes mellitus and high level of low density lipoprotein-cholesterol were independent risk factors for aspirin resistance, while diabetes mellitus was the only independent risk factor for clopidogrel resistance. END was observed in 93 (21.8 %) patients. Diabetes mellitus, high fasting blood glucose level, and concomitant aspirin and clopidogrel resistance were independent risk factors for END. RIS was observed in 40 (9.4 %) patients. Diabetes mellitus, hypertension, and concomitant aspirin and clopidogrel resistance were independent risk factors for RIS. Antiplatelet drug resistance is common in acute minor ischemic stroke patients and is associated with END and RIS after acute minor ischemic stroke in the Chinese population.

CLINICAL TRIAL REGISTRATION INFORMATION

http://www.chictr.org/ . Unique Identifier: ChiCTR-OCH-14004724.

Perfusion-diffusion Mismatch Predicts Early Neurological Deterioration in Anterior Circulation Infarction without Thrombolysis

Perfusion-diffusion mismatch in magnetic resonance imaging (MRI) represents the non-core hypoperfused area in acute ischemic stroke. The mismatch has been used to predict clinical response after thrombolysis in acute ischemic stroke, but its role for predicting early neurological deterioration (END) in acute ischemic stroke without thrombolysis has not been clarified yet. In this study, we prospectively recruited 54 patients with acute non-lacunar ischemic stroke in anterior circulation without thrombolysis. All patients received the first perfusion MRI within 24 hours from stroke onset. Target mismatch profile was defined as a perfusion-diffusion mismatch ratio ≥ 1.2. END was defined as an increase of ≥ 4 points in the National Institute of Health Stroke Scale (NIHSS) score within 72 hours. There were 13 (24.1%) patients developing END, which was associated with larger infarct growth (p = 0.002), worse modified Rankin Scale (p = 0.001) and higher mortality rate at 3 months (p = 0.025). Target mismatch profiles measured by T_max ≥ 4, 5 and 6 seconds were independent predictors for END after correcting initial NIHSS score. Among the 3 T_max thresholds, target mismatch measured by T_max ≥ 6 seconds had the highest odd’s ratio in predicting END (p < 0.01, odd’s ratio = 17), with an 80% sensitivity and a 79.5% specificity. In conclusion, perfusion-diffusion mismatch could identify the patients at high risk of early clinical worsening in acute ischemic stroke without thrombolysis.

Metabolic Syndrome Augments the Risk of Early Neurological Deterioration in Acute Ischemic Stroke Patients Independent of Inflammatory Mediators: A Hospital-Based Prospective Study

Background and Aims. Metabolic syndrome (MetS) has been associated with occurrence and prognosis of ischemic stroke. This study aimed to evaluate whether an association exists between MetS and early neurological deterioration (END) following acute ischemic stroke and the possible role inflammatory biomarkers play. Methods and Results. We conducted a prospective cohort investigation that involved 208 stroke patients within 48 hours from symptom onset. MetS was determined by the modified National Cholesterol Education Program/Adult Treatment Panel III criteria. END was defined as an increase of ⩾1 point in motor power or ⩾2 points in the total National Institutes of Health Stroke Scale (NIHSS) score within 7 days. Univariate logistic regression analysis showed that patients with MetS had a 125% increased risk of END (OR 2.25; 95% CI 1.71–4.86, P = 0.005). After adjustment for fibrinogen and high-sensitivity C-reactive protein, MetS remained significantly correlated to END (OR 2.20; 95% CI 1.10–4.04, P = 0.026) with a 77% elevated risk per additional MetS trait (OR 1.77; 95% CI 1.23–2.58, P = 0.002). Conclusions. This study demonstrated that MetS may be a potential predictor for END after ischemic stroke, which was independent of raised inflammatory mediators.

Aspirin resistance in the acute stages of acute ischemic stroke is associated with the development of new ischemic lesions

BACKGROUND

Aspirin is a primary antiplatelet agent for the secondary prevention of ischemic stroke. However, if aspirin fails to inhibit platelet function, as is expected in acute ischemic stroke (AIS), it may increase the rate of early clinical events. Therefore, we sought to determine whether aspirin resistance in the acute stage was associated with early radiological events, including new ischemic lesions (NILs).

METHODS

This study was a single-center, prospective, observational study conducted between April 2012 and May 2013. Aspirin 300 mg was initially administered followed by maintenance doses of 100 mg daily. The acute aspirin reaction unit (aARU) was consistently measured after 3 hours of aspirin loading. An aARU value ≥550 IU was defined as biological aspirin resistance (BAR). NILs on follow-up diffusion-weighted imaging (DWI) were defined as lesions separate from index lesions, which were not detected on the initial DWI.

RESULTS

A total of 367 patients were analyzed in this study. BAR in aARU was detected in 60 patients (16.3%). On follow-up DWI, 81 patients (22.1%) had NILs, which were frequently in the same territory as the index lesions (79%), pial infarcts (61.7%), and located within the cortex (59.3%). BAR was independently associated with NILs on follow-up DWI (adjusted OR 2.00, 95% CIs 1.01-3.96; p = 0.047).

CONCLUSION

In conclusion, BAR in aARU could be associated with NILs on follow-up DWI in AIS. Therefore, a further prospective study with a longer follow-up period is necessary to evaluate the clinical implications of aARU in AIS.

Low-molecular-weight heparin or dual antiplatelet therapy is more effective than aspirin alone in preventing early neurological deterioration and improving the 6-month outcome in ischemic stroke patients

BACKGROUND AND PURPOSE

Dual antiplatelet therapy (DAT) with clopidogrel and aspirin has been shown to confer greater protection against early neurological deterioration (END) and early recurrent ischemic stroke (ERIS) than aspirin alone in patients who have experienced an acute ischemic stroke. However, few studies have compared the effects of anticoagulation therapy with low-molecular-weight heparin (LMWH), DAT, and aspirin.

METHODS

Patients with acute ischemic stroke (n=1,467) were randomized to therapy groups receiving aspirin (200 mg daily for 14 days, followed by 100 mg daily for 6 months), DAT (200 mg of aspirin and 75 mg of clopidogrel daily for 14 days, then 100 mg of aspirin daily for 6 months), or LMWH (4,000 antifactor Xa IU of enoxaparin in 0.4 mL subcutaneously twice daily for 14 days, followed by 100 mg of aspirin daily for 6 months). The effects of these treatment strategies on the incidence of END, ERIS, and deep-vein thrombosis (DVT) were observed for 10-14 days after treatment, and their impacts on a good outcome were evaluated at 6 months.

RESULTS

The DAT and LMWH were associated with a more significant reduction of END and ERIS within 14 days compared with aspirin-alone therapy. In addition, LMWH was associated with a significantly lower incidence of DVT within 14 days. At 6 months, DAT or LMWH improved the outcome among patients aged >70 years and those with symptomatic stenosis in the posterior circulation or basilar artery compared with aspirin.

CONCLUSIONS

LMWH or DAT may be more effective than aspirin alone for reducing the incidence of END and ERIS within 14 days, and is associated with improved outcomes in elderly patients and those with stenosis in the posterior circulation or basilar artery at 6 months poststroke.

Incidence, causes and predictors of neurological deterioration occurring within 24 h following acute ischaemic stroke: a systematic review with pathophysiological implications

Early neurological deterioration (END) following ischaemic stroke is a serious event with manageable causes in only a fraction of patients. The incidence, causes and predictors of END occurring within 24 h of acute ischaemic stroke (END24) have not been systematically reviewed. We systematically reviewed Medline and Embase from January 1990 to April 2013 for all studies on END24 following acute ischaemic stroke (<8 h from onset). We recorded the incidence and presumed causes of and factors associated with END24. Thirty-six studies were included. Depending on the definition used, the incidence of END24 markedly varied among studies. Using the most widely used change in National Institutes of Health Stroke Scale ≥4 definition, the pooled incidence was 13.8% following thrombolysis, ascribed to intracranial haemorrhage and malignant oedema each in ∼20% of these. As other mechanisms were rarely reported, in the majority no clear cause was identified. Few data on END24 occurring in non-thrombolysed patients were available. Across thrombolysed and non-thrombolysed samples, the strongest and most consistent admission predictors were hyperglycaemia, no prior aspirin use, prior transient ischaemic attacks, proximal arterial occlusion and presence of early CT changes, and the most consistent 24 h follow-up associated factors were no recanalisation/reocclusion, large infarcts and intracranial haemorrhage. Finally, END24 was strongly predictive of poor outcome. The above findings are discussed with emphasis on END without a clear mechanism. Data on incidence and predictors of the latter subtype is scarce, and future studies using systematic imaging protocols should address its underlying pathophysiology. This may in turn lead to rational preventative and therapeutic measures for this ominous event.

Mechanisms of Unexplained Neurological Deterioration After Intravenous Thrombolysis

Background and Purpose—

Unstable clinical course characterizes the first 24 hours after thrombolysis for anterior circulation stroke, including early neurological deterioration (END), a secondary complication consistently predictive of poor outcome. Apart from straightforward causes, such as intracerebral hemorrhage and malignant edema, the mechanism of END remains unclear in the majority of cases (END unexplained ). Based on the core/penumbra model, we tested the hypothesis that END unexplained is caused by infarct growth beyond the initial penumbra and assessed the associated vascular patterns.

Methods—

From our database of consecutive thrombolyzed patients (n=309), we identified 10 END unexplained cases who had undergone both admission and 24-hour MRI. Diffusion-weighted imaging lesion growth both within and beyond the acute penumbra (T max >6 seconds) was mapped voxelwise. These 10 cases were compared with 30 no-END controls extracted from the database blinded to 24-hour diffusion-weighted imaging to individually match cases (3/case) according to 4 previously identified clinical and imaging variables.

Results—

As predicted, lesion growth beyond initial penumbra was present in 9 of 10 END unexplained patients (substantial in 8) and its volume was significantly larger in cases than controls (2 P =0.047). All END unexplained cases had proximal arterial occlusion initially, of which only 2 had recanalized at 24 hours.

Conclusions—

In this exploratory study, most instances of END unexplained were related to diffusion-weighted imaging growth beyond acute penumbra. Consistent presence of proximal occlusion at admission and lack of recanalization at 24 hours in most cases suggest that hemodynamic factors played a key role, via for instance systemic instability/collateral failure or secondary thromboembolic processes. Preventing END after tissue-type plasminogen activator using, eg, early antithrombotics may therefore be feasible.

Hemodynamic factors may play a critical role in neurological deterioration occurring within 72 hrs after lacunar stroke

Background

Whether a perfusion defect exists in lacunar infarct and whether it is related to early neurological deterioration (END) is still under debate. The aim of this study was to evaluate whether END in lacunar infarct is related to a perfusion defect using diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI) and perfusion MR imaging.

Methods

One hundred and forty-one consecutive patients had an MRI scan within 30 hours after onset of symptoms and 43 patients with acute lacunar infarct and classic lacunar syndrome were recruited. The MRI sequences included DWI, DTI and cerebral blood flow (CBF) maps to respectively represent the topographic locations of acute infarcts, the corticospinal tract and perfusion defects. The END was defined in reference to the National Institute of Health Stroke Scale (NIHSS) as an increase ≧2 within 72 hours. Cohen's Kappa coefficient was used to examine the reliability between the 2 image readers. A multivariate logistic regression model was constructed adjusting for baseline variables.

Results

Ten out of the 43 patients had END. Patients having END was significantly associated with lower chances of favorable and good outcomes at 3 months (p = 0.01 and p = 0.002, respectively). END was predicted when the non-core hypoperfused area overlapped on the corticospinal tract, which is defined as the expected END profile. Cohen's Kappa coefficient between the 2 image readers to define images of expected END profiles was 0.74. In 15 patients with expected END profile, 9 had END clinically, whereas 28 patients had no expected END profile, and only 1 patient had END (p<0.0001). After adjusting for sex, the expected END profile was still associated with END (odds ratio, 42.2; p = 0.002).

Conclusion

Our study demonstrated that the END in acute lacunar stroke is likely related to the transformation of non-core hypoperfused area into infarction in the anatomy of corticospinal tracts.

Clopidogrel Plus Aspirin Prevents Early Neurologic Deterioration and Improves 6-Month Outcome in Patients With Acute Large Artery Atherosclerosis Stroke

Aims:

To evaluate the effects of treatments with clopidogrel plus aspirin (dual therapy) on early neurological deterioration (END) and outcomes at 6 months in patients with acute large artery atherosclerosis (LAA) stroke.

Methods:

A total of 574 patients with LAA stroke were randomly assigned to receive either dual therapy or aspirin alone (monotherapy). The primary outcome was END. Secondary outcomes included recurrent ischemic stroke (RIS) and outcomes at 6 months.

Results:

The prevalence of END and RIS was lower in patients on dual therapy than in those on monotherapy during the 30 days. At 6 months, dual therapy improved outcomes among older patients and those with symptomatic stenosis in the posterior circulation and basilar artery.

Conclusion:

Clopidogrel plus aspirin is superior to aspirin alone for reducing END and RIS within 30 days and improves outcomes in certain subgroups at 6 months.

Xueshuantong improves cerebral blood perfusion in elderly patients with lacunar infarction

A total of 64 patients with acute lacunar infarction were enrolled within 24 hours of onset. The patients received conventional therapy (antiplatelet drugs and hypolipidemic drugs) alone or conventional therapy plus 450 mg Xueshuantong once a day. The main ingredient of the Xueshuantong lyophilized powder used for injection was Panax notoginseng saponins. Assessments were made at admission and at discharge using the National Institutes of Health Stroke Scale, the Activity of Daily Living and the Mini-Mental State Examination. Additionally, the relative cerebral blood flow, relative cerebral blood volume and relative mean transit time in the region of interest were calculated within 24 hours after the onset of lacunar infarction, using dynamic susceptibility contrast magnetic resonance perfusion imaging technology. Patients underwent a follow-up MRI scan after 4 weeks of treatment. There was an improvement in the Activity of Daily Living scores and a greater reduction in the scores on the National Institutes of Health Stroke Scale in the treatment group than in the control group. However, the Mini-Mental State Examination scores showed no significant differences after 4 weeks of treatment. Compared with the control group, the relative cerebral blood flow at discharge had increased and showed a greater improvement in the treatment group. Furthermore, there was a reduction in the relative mean transit time at discharge and the value was lower in the treatment group than in the control group. The experimental findings indicate that Xueshuantong treatment improves neurological deficits in elderly patients with lacunar infarction, and the mechanism may be related to increased cerebral perfusion.

Acute Diffusion-Weighted Imaging Lesion Patterns Predict Progressive Small Subcortical Infarct in the Perforator Territory of the Middle Cerebral Artery

Background

Single small subcortical infarct (SSSI) is generally considered to have a fair outcome. However, early neurological deterioration (END), a relatively unfavorable clinical course occurring during the acute phase of infarction, is not uncommon.

Aims

The aim of this study was to investigate the relationship between lesion patterns detected by diffusion-weighted imaging (DWI) and the presence of END in patients with acute SSSI in the perforator territory of the middle cerebral artery (MCA).

Methods

Three hundred twelve patients with acute SSSI in the perforator territory of MCA were prospectively recruited from Jinling Hospital between January 2010 and May 2013. Acute DWI lesion patterns were classified as proximal SSSI (pSSSI) or distal SSSI (dSSSI) patterns, according to the relationship between lesion location and the parent artery. Neurological deficits were evaluated using the National Institutes of Health Stroke Scale (NIHSS) at admission and continued over the following 72 h 1–3 times a day. END was defined as an increase in NIHSS score ⩾2 points during the first 72 h after admission.

Results

Of the total 312 patients, the pSSSI pattern was found in 139 (44·55%) patients and the dSSSI pattern in 173 (55·45%) patients. Statistical analysis suggested that the indicators for small-artery disease (hypertension and leukoaraiosis) and atherosclerosis (diabetes mellitus and cerebral atherosclerosis) significantly differed according to lesion patterns ( P < 0·05). During hospitalization, 88 (28·21%) patients experienced END. Univariate analysis revealed that female sex ( P = 0·004), pSSSI pattern ( P < 0·001), initial NIHSS ( P = 0·001), lesion diameter ( P = 0·005), ipsilateral large-artery stenosis ( P = 0·008), and concomitant intracranial atherosclerotic stenosis ( P = 0·021) were significantly associated with END. After adjusting for confounding factors, pSSSI pattern was an independent predictor of END (OR 1·871, 95% CI 1·095–3·198, P = 0·022). In the further subgroup analysis of patients with different etiologies, pSSSI pattern was found to be independently associated with END in patients with large-artery atherosclerosis (OR 3·593, 95% CI 1·268–11·057, P = 0·026) and in patients with small-artery disease (OR 2·523, 95% CI 1·121–5·676, P = 0·025), but not in patients with cardioembolism (OR 0·854, 95% CI 0·147–4·953, P = 0·861).

Conclusions

pSSSI pattern was closely related to END in acute SSSI caused by large-artery atherosclerosis and small-artery disease in the perforator territory of the MCA.

Asymmetrical cortical vessel sign on susceptibility-weighted imaging: a novel imaging marker for early neurological deterioration and unfavorable prognosis

BACKGROUND AND PURPOSE

Susceptibility-weighted imaging (SWI) is a high spatial resolution technique that can indirectly demonstrate increased cerebral oxygen extraction. Our aim was to assess whether asymmetric cortical vessel sign (ACVS) on SWI could be associated with early neurological deterioration (END) as well as 90-day unfavorable outcome in patients with acute ischaemic stroke.

MATERIALS AND METHODS

Consecutive patients with acute middle cerebral artery (MCA) territory infarction were prospectively enrolled. ACVS was defined as more and/or larger vessels with greater signal loss than those in the opposite hemisphere on minimum intensity projection of SWI. The neurofunctional fluctuation during acute phase as well as 90-day outcomes were assessed. A National Institutes of Health Stroke Scale increment ≥2 points and ≥4 points despite standard treatment in the first 72 h after admission was defined as END2 and END4, respectively.

RESULTS

In all, 572 patients were finally enrolled. ACVS on SWI was present in 39 (6.8%) subjects. Multivariate analysis indicated that ACVS is an independent predictor for END2 [odds ratio (OR) 4.47, 95% confidence interval (CI) 1.99-10.05) and END4 (OR 4.24, 95% CI 1.94-9.23). Furthermore, ACVS also correlates with 90-day unfavorable outcome defined as a modified Rankin Scale score >1 point (OR 2.93, 95% CI 1.15-7.48). Both positive and negative predictive values of ACVS for END2, END4 and 90-day prognosis were reasonable and both could be slightly enhanced as long as patients with contralateral artery stenosis or occlusion were excluded.

CONCLUSION

In patients with MCA territory acute ischaemic stroke, especially in those without contralateral internal carotid artery/MCA stenosis or occlusion, ACVS might be considered as a neuroimaging predictor for END and unfavorable prognosis.

Unexplained Early Neurological Deterioration After Intravenous Thrombolysis

Background and Purpose—

Early neurological deterioration (END) after anterior circulation stroke is a serious clinical event strongly associated with poor outcome. Regarding specifically END occurring within 24 hours of intravenous recombinant tissue-type plasminogen activator, apart from definite causes such as symptomatic intracranial hemorrhage and malignant edema whose incidence, predictors, and clinical management are well established, little is known about END without clear mechanism (END unexplained ).

Methods—

We analyzed 309 consecutive patients thrombolysed intravenously ≤4.5 hours from onset of anterior circulation stroke. END unexplained was defined as a ≥4-point deterioration on 24-hour National Institutes of Health Stroke Scale, without definite mechanism on concomitant imaging. END unexplained and no-END patients were compared for pretreatment clinical and imaging (including magnetic resonance diffusion and diffusion/perfusion mismatch volumes) data and 24-hour post-treatment clinical (including blood pressure and glycemic changes) and imaging (24-hour recanalization) data, using univariate logistic regression. Exploratory multivariate analysis was also performed after variable reduction, with bootstrap analysis for internal validation.

Results—

Among 33 END patients, 23 (7% of whole sample) had END unexplained . END unexplained was associated with poor 3-month outcome ( P <0.01). In univariate analysis, admission predictors of END unexplained included no prior use of antiplatelets ( P =0.02), lower National Institutes of Health Stroke Scale score ( P <0.01), higher glycemia ( P =0.03), larger mismatch volume ( P =0.03), and proximal occlusion ( P =0.01), with consistent results from the multivariate analysis. Among factors recorded during the first 24 hours, only no recanalization was associated with END unexplained in multivariate analysis ( P =0.02).

Conclusions—

END unexplained affected 7% of patients and accounted for most cases of END. Several predictors and associated factors were identified, with important implications regarding underlying mechanisms and potential prevention of this ominous event.

Low-molecular-weight heparin is more effective than aspirin in preventing early neurologic deterioration and improving six-month outcome

BACKGROUND

We evaluated the efficacy of low-molecular-weight heparin (LMWH) relative to aspirin in preventing early neurologic deterioration (END), venous thromboembolism (VTE), and outcomes at 6 months.

METHODS

Patients were randomly assigned to receive either subcutaneous enoxaparin 4000 anti-factor Xa IU/0.4 mL twice daily or oral aspirin 200 mg daily for 10 days. After day 10, all subjects received aspirin 100 mg once daily for 6 months. We assessed whether LMWH was superior to aspirin in preventing END and VTE within the first 10 days after index stroke and evaluated 6-month outcomes.

FINDINGS

Of the total 1368 patients, 7.89% suffered from END, and 2.85% suffered from deep-vein thrombosis during the first 10 days, with a significance difference between the LMWH group and aspirin group (3.95%, 1.46% versus 11.82%, 4.23%, respectively). At 6 months, there was a significant difference in the frequency of good outcomes among patients over the median age of 70 years (LMWH 63.8% versus aspirin 44.6%). The benefit of LMWH was also significant in patients with symptomatic stenosis of the posterior circulation and basilar artery (75.2% and 82% for LMWH versus 40.5% and 48% for aspirin, respectively).

CONCLUSIONS

For patients with acute ischemic stroke, treatment with LMWH within 48 hours of stroke until 10 days later may reduce END and deep-vein thrombosis during the first 10 days. LMWH appears to have advantages over aspirin in certain subgroups, such as elderly patients and patients with posterior circulation and basilar artery stenosis.

A comparative study of dual versus monoantiplatelet therapy in patients with acute large-artery atherosclerosis stroke

BACKGROUND

Antiplatelet drugs are recommended for patients with acute noncardioembolic stroke. However, few randomized clinical trials have investigated the safety and efficacy of dual antiplatelet therapy for these patients. The aim of this study was to evaluate the effects of treatment with clopidogrel and aspirin (combination therapy) and aspirin alone (monotherapy) on neurologic deterioration, platelet activation, and other short-term outcomes in patients with acute large-artery atherosclerosis stroke.

MATERIALS AND METHODS

Altogether 574 patients with acute (≤2 days) large-artery atherosclerosis stroke were randomly assigned to receive either combined clopidogrel and aspirin or aspirin alone. Platelet aggregation and platelet-leukocyte aggregation studies were performed at days 1 and 30. Primary outcomes including recurrent ischemic stroke, neurologic deterioration, periphery vascular events, and myocardial infarction were monitored. Safety endpoints were hemorrhagic episodes and death.

RESULTS

The prevalence of neurologic deterioration and recurrent ischemic stroke were lower in patients in the combination therapy group than in those of the monotherapy group (3.52% versus 9.78% and 1.76% versus 6.29%, respectively). At day 30 of treatment, the platelet aggregations and platelet-leukocyte aggregates were lower in patients who were treated with clopidogrel and aspirin than in patients given aspirin alone (P < .001).

CONCLUSIONS

For patients with acute large-artery atherosclerosis stroke, treatment with clopidogrel and aspirin for 1 month provided significantly greater inhibition of platelet activity than aspirin alone. Thus, dual therapy can be safer and more effective in reducing ischemic stroke recurrence and neurologic deterioration.

Reversal of the neurological deficit in acute stroke with the signal of efficacy trial of auto-BPAP to limit damage from suspected sleep apnea (Reverse-STEAL): study protocol for a randomized controlled trial

Background

Although the negative impact of sleep apnea on the clinical course of acute ischemic stroke (AIS) is well known, data regarding non-invasive ventilation in acute patients are scarce. Several studies have shown its tolerability and safety, yet no controlled randomized sequential phase studies exist that aim to establish the efficacy of early non-invasive ventilation in AIS patients.

Methods/design

We decided to examine our hypothesis that early non-invasive ventilation with auto-titrating bilevel positive airway pressure (auto-BPAP) positively affects short-term clinical outcomes in AIS patients. We perform a multicenter, prospective, randomized, controlled, third rater- blinded, parallel-group trial. Patients with AIS with proximal arterial obstruction and clinically suspected sleep apnea will be randomized to standard stroke care alone or standard stroke care plus auto-BPAP. Auto-BPAP will be initiated within 24 hours of stroke onset and performed for a maximum of 48 hours during diurnal and nocturnal sleep. Patients will undergo unattended cardiorespiratory polygraphy between days three and five to assess sleep apnea. Our primary endpoint will be any early neurological improvement on the NIHSS at 72 hours from randomization. Safety, tolerability, short-term and three-months functional outcomes will be assessed as secondary endpoints by un-blinded and blinded observers respectively.

Discussion

We expect that this study will advance our understanding of how early treatment with non-invasive ventilation can counterbalance, or possibly reverse, the deleterious effects of sleep apnea in the acute phase of ischemic stroke. The study will provide preliminary data to power a subsequent phase III study.

Trial registration

Clinicaltrials.gov Identifier: NCT01812993

A proposal for the classification of etiologies of neurologic deterioration after acute ischemic stroke

BACKGROUND

Neurologic deterioration (ND) occurs in one third of patients with ischemic stroke and contributes to morbidity and mortality in these patients. Etiologies of ND and clinical outcome according to ND etiology are incompletely understood.

METHODS

We conducted a retrospective investigation of all patients with ischemic stroke admitted to our center (July 2008 to December 2010), who were known to be last seen normal less than 48 hours before arrival. First-time episodes of ND during hospitalization were collected in which a patient experienced a 2-point increase or more in National Institutes of Health Stroke Scale score within a 24-hour period. Proposed etiologies of reversible ND include infectious, metabolic, hemodynamic, focal cerebral edema, fluctuation, sedation, and seizure, whereas new stroke, progressive stroke, intracerebral hemorrhage, and cardiopulmonary arrest were nonreversible.

RESULTS

Of 366 included patients (median age 65 years, 41.4% women, 68.3% black), 128 (34.9%) experienced ND (median age 69 years, 42.2% women, 68.7% black). Probable etiologies of ND were identified in 90.6% of all first-time ND events. The most common etiology of ND, progressive stroke, was highly associated with poor outcome but not death. Etiologies most associated with mortality included edema (47.8%), new stroke (50%), and intracerebral hemorrhage (42.1%).

CONCLUSIONS

In the present study, the authors identified probable etiologies of ND after ischemic stroke. Delineating the cause of ND could play an important role in the management of the patient and help set expectations for prognosis after ND has occurred. Prospective studies are needed to validate these proposed definitions of ND.

The sNIHSS-4 predicts outcome in right and left anterior circulation strokes

BACKGROUND AND PURPOSE

Stroke severity measured by the National Institutes of Health Stroke Scale (NIHSS) is a strong predictor of functional outcome. A short version, the sNIHSS-5, scoring only strength in right and left leg, gaze, visual fields and language, was developed for use in the prehospital setting. Because scoring both legs in anterior circulation strokes is not contributive, we assessed the value of a 4-item score (the sNIHSS-4), omitting the item 'strength in the unaffected leg', in predicting stroke outcome.

METHODS

The study population consisted of anterior circulation ischemic stroke patients who participated in the LUB-INT-9 trial. We included all patients in whom the following data were available: NIHSS within 6h after stroke onset and daily between days 2 and 5, and the 12-week modified Rankin Scale (mRS) score. Poor outcome was defined as a mRS score>3.

RESULTS

There was an excellent correlation between the NIHSS and sNIHSS-4 at all time points for both left and right-sided strokes. Scores at day 2 were a good predictor of poor outcome. Cutoff scores for NIHSS and sNIHSS-4 at day 2 were 15 and 5 in left hemispheric strokes, and 12 and 4 in right hemispheric strokes.

CONCLUSION

The sNIHSS-4 is as good as the NIHSS at predicting stroke outcome in both right and left anterior circulation strokes.

Progressive lacunar stroke: review of mechanisms, prognostic features, and putative treatments

Lacunar stroke is generally considered to have a fair outcome. However 20-30% of patients with lacunar stroke worsen neurologically in hours or days after onset, reaching eventually an unexpectedly severe disability status. In the field of acute stroke, progressive lacunar stroke remains an important unresolved practice problem, because as yet no treatment does exist proven to prevent or halt progression. Pathophysiology of progression is yet incompletely understood. Hemodynamic factors, extension of thrombosis, excitotoxicity, and inflammation, have been proposed as possible mechanisms of progression. A few clinical studies also aimed at establishing presentation features that may help identifying patients at risk of deterioration. In this paper, we review hypothesized mechanisms of lacunar stroke progression and possible markers of early deterioration. Moreover, based on putative mechanisms and suggestions from reported evidence, we propose a few treatments that seem worthy to be tested by randomized clinical trials.

NIHSS and acute complications after anterior and posterior circulation strokes

Background

The purpose of this study was to determine whether the National Institutes of Health Stroke Scale (NIHSS) score was associated with inhospital neurological and medical complications (NMC) in patients with posterior circulation infarction.

Methods

This retrospective study included all patients admitted to our stroke unit during a one-year period (n = 289). NMC included neurological deterioration (ie, worsening by 4 points or more of the NIHSS score during the hospital stay) and all other medical complications based on what was recorded in the patients’ charts.

Results

Seventy-nine patients (27%) experienced NMC. In posterior circulation infarction patients (n = 90), patients with NMC had a higher baseline NIHSS score (10.9 versus 2.2, P = 0.004) and a baseline NIHSS score >2 (78% versus 36%, P = 0.003). In stepwise logistic regression, an NIHSS score >2 (odds ratio: 8.2; 95% confidence interval: 1.64–41.0; P = 0.01) was associated with NMC. Similar results were observed for anterior circulation infarction patients but with a higher cutoff value for NIHSS score.

Conclusion

In ischemic stroke patients, an increased baseline NIHSS score was associated with an increased risk of NMC. This association applied to anterior-circulation as well as posterior circulation stroke, although zero on the NIHSS for posterior circulation stroke does not mean the absence of NMC during hospitalization. The clinical significance of these findings requires further evaluation in larger prospective studies.

Demographic, clinical, and radiologic predictors of neurologic deterioration in patients with acute ischemic stroke

One-third of patients with acute ischemic stroke develop early neurologic worsening, which is associated with increased mortality and long-term functional disability. We investigated the predictive factors for neurologic deterioration in patients with acute ischemic stroke within 1 week of onset. We retrospectively investigated 643 patients who were admitted within 2 days of acute ischemic stroke between April 2007 and March 2010. Neurologic deterioration was defined as an increase of 4 points or more in the National Institutes of Health Stroke Scale (NIHSS) score within 1 week of admission. We retrieved data on demographic and clinical characteristics, medications, and stroke subtypes. Out of 537 patients, deterioration was noted in 64 patients (11.9%; deterioration group). Multivariate analysis identified history of myocardial infarction (P < .001), NIHSS score ≥8 at onset (P < .001), high leukocyte count (P = .035), low-density lipoprotein cholesterol ≥140 mg/dL (P = .002), and hemoglobin A1c ≥7% (P = .006) as significant factors associated with deterioration. Branch atheromatous disease was more frequent in the deterioration group, and >90% of patients with deterioration either were discharged to nursing home care or died. Multivariate analysis of magnetic resonance imaging findings identified internal carotid/middle cerebral artery occlusion (each P < .001), striate capsular infarction (P = .030), pontine infarction (P = .047), and lesion size of 15-30 mm (P = .011) as independent factors associated with deterioration. Stroke patients with a high low-density lipoprotein level, high hemoglobin A1c level on admission, a history of myocardial infarction, and high NIHSS score are at high risk for neurologic deterioration. Patients with multiple risk factors for deterioration can benefit most from intensive monitoring.

Infarction of 'non-core-non-penumbral' tissue after stroke: multivariate modelling of clinical impact

There is considerable intersubject variability in early neurological course after anterior circulation stroke, yet the pathophysiology underlying this variability is not fully understood. Here, we hypothesize that, although not predicted by current pathophysiological models, infarction of 'non-core-non-penumbral' (i.e. clinically silent) brain tissue may nevertheless occur, and negatively influence clinical course over and above the established positive impact of penumbral salvage. In order to test this hypothesis, non-core-non-penumbral tissue was identified in two independent prospectively recruited cohorts, using computed tomography perfusion, and magnetic resonance perfusion- and diffusion-weighted imaging, respectively. Follow-up structural magnetic resonance imaging was obtained about 1 month later in all patients to map the final infarct. The volumes of both the acutely silent but eventually infarcted tissue, and the eventually non-infarcted penumbra, were determined by performing voxel-wise analysis of the acute and follow-up image sets, using previously validated perfusion thresholds. Early neurological course was expressed as change in National Institutes of Health Stroke Scale scores between the acute and 1-month assessments, relative to the acute score. The relationship between the acutely silent but eventually infarcted tissue volume and early neurological course was tested using a multivariate regression model that included the volume of non-infarcted penumbra. Thirty-four and 58 patients were recruited in the computed tomography perfusion and magnetic resonance perfusion cohorts, respectively (mean onset-to-imaging time: 136 and 156 min; 27 and 42 patients received intravenous thrombolysis, respectively). Infarction of acutely silent tissue was identified in most patients in both cohorts. Although its volume (median 0.2 and 2 ml, respectively) was much smaller than that of salvaged penumbra (59.3 and 93 ml, respectively), it was substantial in ∼10% of patients. As expected, salvaged penumbra strongly positively influenced early neurological course. Even after correcting for the latter effect in the multivariate model, infarction of acutely silent tissue independently negatively influenced early neurological course in both cohorts (P=0.018 and 0.031, respectively). This is the first systematic study to document infarction of acutely silent tissue after anterior circulation stroke, and to show that it affects a sizeable fraction of patients and has the predicted negative impact on clinical course. These findings were replicated in two independent cohorts, regardless of the perfusion imaging modality used. Preventing infarction of the tissue not initially at risk should have direct clinical benefit.

Total mismatch: negative diffusion-weighted imaging but extensive perfusion defect in acute stroke

BACKGROUND AND PURPOSE

The perfusion-weighted imaging (PWI)/diffusion-weighted imaging (DWI) mismatch may identify patients who benefit from thrombolysis. However, some patients exhibit a "total mismatch," ie, negative DWI but extensive PWI defect. We aimed to assess clinical and MRI data of these patients.

METHODS

From June 2007 to December 2008, patients with anterior circulation ischemic stroke were evaluated for a "total mismatch" profile. MRI was performed at admission and at day 1. The score was assessed at baseline and the modified Rankin scale score was assessed at day 30.

RESULTS

Among 52 patients, 3 showed a total mismatch with arterial occlusion confirmed on magnetic resonance angiography. All had fluctuating symptoms (National Institutes of Health Stroke Scale scores, 0 to 10) and received intravenous tissue plasminogen activator. Day 1 DWI disclosed minimal changes in all patients. Outcome was favorable in all patients (day 30 modified Rankin scale, 0-1).

CONCLUSION

PWI may be helpful for treatment decisions in patients without DWI damage and fluctuating clinical course.