Mar Castellanos

Mechanical Thrombectomy With the Solitaire AB Device in Large Artery Occlusions of the Anterior Circulation: A Pilot Study

Background and Purpose— To describe the safety and effectiveness of a self-expanding and fully retrievable stent (Solitaire AB; ev3 Inc, Plymouth, MN) in revascularization of patients with acute ischemic stroke. Methods— Prospective, single-center study of 20 patients with an acute ischemic stroke attributable to a large artery occlusion of the anterior circulation within the first 8 hours from symptoms onset (median National Institutes of Health Stroke Scale, 19 [interquartile range, 15–23]). The occlusion site was middle cerebral artery in 12 patients, proximal internal carotid artery/middle cerebral artery tandem occlusion in 3 patients, and terminus internal carotid artery in 5 patients. Thrombectomy was used as rescue therapy in 2 patients who were refractory to intra-arterial plasminogen activator, and in 3 patients in whom successful recanalization with the MERCI retriever was not achieved. Results— Successful revascularization defined as thrombosis in cerebral ischemia grade 2b or 3 was achieved in 18 of 20 (90%) treated vessels, and 16 patients showed immediate restoration of flow after stent deployment. The mean number of passes for maximal recanalization was 1.4, and the median (quartiles) time from groin puncture to recanalization was 50 (38–71) minutes. No case required adjuvant therapy after deployment of the embolectomy device. No significant procedural events occurred. Symptomatic intracranial hemorrhage was found in 2 (10%) patients, 4 (20%) patients died during the 90-day follow-up period, and 45% of patients showed good functional outcome at 3 months (modified Rankin Scale score ≤2). Conclusions— These results suggest that the Solitaire AB device can rapidly, safely, and effectively retrieve clots from the middle cerebral artery and terminus internal carotid artery within 8 hours from symptoms onset.

Plasma Metalloproteinase-9 Concentration Predicts Hemorrhagic Transformation in Acute Ischemic Stroke

Background and Purpose— Matrix metalloproteinase-9 (MMP-9) activity has been associated with hemorrhagic transformation (HT) in experimental models of cerebral ischemia. Our aim was to investigate the relationship between MMP-9 concentrations in blood within 24 hours of stroke onset and subsequent HT of cerebral infarction. Methods— We studied 250 patients with a hemispheric ischemic stroke of 7.8±4.5 hours’ duration. Early CT signs of cerebral infarction were evaluated on admission. The HT and infarct volume were analyzed from the CT performed on days 4 through 7. MMP-9 levels were determined by enzyme-linked immunosorbent assay in blood samples obtained on admission. Results— HT was observed in 38 patients (15.2%): 24 (63.2%) had a hemorrhagic infarction, and 14 (36.8%) had a parenchymal hematoma. A total of 108 patients (43%) received anticoagulants before the second CT scan. Systolic and diastolic blood pressures, body temperature, frequency of early CT signs of ischemia (92% versus 22%), and treatment with anticoagulants (79% versus 37%) were significantly higher in the group with HT (P <0.001). Mean infarct volume was 126±60 cm3 in the HT group and 90±68 cm3 in the group without HT (P =0.003). Median (quartiles) plasma MMP-9 concentrations were higher in the HT group (193 [163, 213] versus 62 [40, 93] ng/mL, P <0.001), even in the 24 patients seen within 3 hours of symptom onset (P =0.014). MMP-9 levels ≥140 ng/mL had a positive and negative predictive value of HT of 61% and 97%, respectively. MMP-9 ≥140 ng/mL was associated with HT (odds ratio, 12; 95% confidence interval, 3 to 51;P <0.001) after adjustment for potential confounders and final infarct volume. Conclusions— High plasma MMP-9 concentration in the acute phase of a cerebral infarct is an independent biochemical predictor of HT in all stroke subtypes.

Statin treatment withdrawal in ischemic stroke A controlled randomized study

Background: Pretreatment with statins has been shown to reduce brain injury in cerebral ischemia. In this controlled randomized study, we investigated the influence of statin pretreatment and its withdrawal on the outcome of acute ischemic stroke patients. Methods: From 215 patients admitted within 24 hours of a hemispheric ischemic stroke, 89 patients on chronic statin treatment were randomly assigned either to statin withdrawal for the first 3 days after admission (n = 46) or to immediately receive atorvastatin 20 mg/day (n = 43). The primary outcome event was death or dependency (modified Rankin Scale [mRS] score > 2) at 3 months. Early neurologic deterioration (END) and infarct volume at days 4 to 7 were secondary outcome variables. In a secondary analysis, outcome variables were compared with the nonrandomized patients without previous statin therapy (n = 126). Results: Patients with statin withdrawal showed a higher frequency of mRS score > 2 at the end of follow-up (60.0% vs 39.0%; p = 0.043), END (65.2% vs 20.9%; p < 0.0001), and greater infarct volume (74 [45, 126] vs 26 [12, 70] mL; p = 0.002) compared with the non–statin-withdrawal group. Statin withdrawal was associated with a 4.66 (1.46 to 14.91)–fold increase in the risk of death or dependency, a 8.67 (3.05 to 24.63)–fold increase in the risk of END, and an increase in mean infarct volume of 37.63 mL (SE 10.01; p < 0.001) after adjusting for age and baseline stroke severity. Compared with patients without previous treatment with statins, statin withdrawal was associated with a 19.01 (1.96 to 184.09)–fold increase in the risk of END and an increase in mean infarct volume of 43.51 mL (SE 21.91; p = 0.048). Conclusion: Statin withdrawal is associated with increased risk of death or dependency at 90 days. Hence, this treatment should be continued in the acute phase of ischemic stroke.

The Increase of Circulating Endothelial Progenitor Cells After Acute Ischemic Stroke Is Associated With Good Outcome

Background and Purpose— Increased circulating endothelial progenitor cells (EPC) have been associated with a low cardiovascular risk and may be involved in endothelial cell regeneration. The present study was designed to evaluate the prognostic value of EPC in acute ischemic stroke. Methods— Forty-eight patients with a first-ever nonlacunar ischemic stroke were prospectively included in the study within 12 hours of symptoms onset. Stroke severity was evaluated by the National Institutes of Health Stroke Scale, and functional outcome was assessed at 3 months by the modified Rankin Scale (mRS). Infarct volume growth between admission and days 4 to 7 was measured on multiparametric MRI. EPC colonies were defined as early outgrowth colony-forming unit-endothelial cell (CFU-EC). The increment of CFU-EC was quantified during the first week and defined as the absolute difference between the number of CFU-EC at day 7 and admission. The influence of CFU-EC increase on good functional outcome (mRS ≤2) and infarct growth was analyzed by logistic regression and linear models. Results— Patients with good outcome (n=25) showed a higher CFU-EC increment during the first week (median [quartiles], 23 [11, 36] versus −3 [−7, 1], P<0.0001) compared with patients with poor outcome. CFU-EC increment ≥4 during the first week was associated with good functional outcome at 3 months (odds ratio, 30.7; 95% CI, 2.4 to 375.7; P=0.004) after adjustment for baseline stroke severity, ischemic volume and thrombolytic treatment. For each unit increase in the CFU-EC the mean reduction in the growth of infarct volume was 0.39 (0.03 to 0.76) mL (P=0.033). Conclusions— The increase of circulating EPC after acute ischemic stroke is associated with good functional outcome and reduced infarct growth. These findings suggest that EPC might participate in neurorepair after ischemic stroke.

The clinical-DWI mismatch: a new diagnostic approach to the brain tissue at risk of infarction.

Objective: To evaluate the usefulness of a mismatch between the severity of acute clinical manifestations and the diffusion-weighted imaging (DWI) lesion in predicting early stroke outcome and infarct volume. Methods: One hundred sixty-six patients with a hemispheric ischemic stroke of <12 hours’ duration were studied. The NIH Stroke Scale (NIHSS) score and the volume of DWI lesion were measured on admission and at 72 ± 12 hours. Infarct volume was measured on T2-weighted or fluid-attenuated inversion recovery images at day 30. Early neurologic deterioration (END) was defined as an increase of ≥4 points between the two NIHSS evaluations. Thirty-eight patients received IV thrombolysis or abciximab. Clinical–DWI mismatch (CDM) was defined as NIHSS score of ≥8 and ischemic volume on DWI of ≤25 mL on admission. The adjusted influence of CDM on END, DWI lesion enlargement at 72 hours, and infarct growth at day 30 was evaluated by logistic regression analysis and generalized linear models. Results: CDM was found in 87 patients (52.4%). Patients with CDM had a higher risk of END than patients without CDM because NIHSS < 8 (odds ratio [OR], 9.0; 95% CI,1.9 to 42) or DWI lesion > 25 mL (OR, 2.0; 95% CI, 0.8 to 4.9). CDM was associated with an increase of 46 to 68 mL in the mean volume of DWI lesion enlargement and infarct growth in comparison with non-CDM. All the effects were even greater and significant in patients not treated with reperfusion therapies. Conclusions: Acute stroke patients with an NIHSS score of ≥8 and DWI volume of ≤25 mL have a higher probability of infarct growth and early neurologic deterioration. The new concept of CDM may identify patients with tissue at risk of infarction for thrombolytic or neuroprotective drugs.

Plasma Cellular-Fibronectin Concentration Predicts Hemorrhagic Transformation After Thrombolytic Therapy in Acute Ischemic Stroke

Background and Purpose— Elevated plasma levels of cellular fibronectin (c-Fn) reflect vascular damage, so c-Fn might be a marker of secondary bleeding risk in cerebral ischemia. We investigated whether high plasma levels of c-Fn were associated with hemorrhagic transformation (HT) after treatment with tissue plasminogen activator (tPA) in patients with acute stroke. Methods— Eighty-seven patients (mean age: 67±12) received tPA after the ECASS II criteria (mean time to infusion: 160±46 minutes; median NIHSS: 12). HT and hypodensity volume were studied on computed tomography (CT) performed 24 to 36 hours after treatment. HT was classified according to the ECASS II definitions. c-Fn and matrix metalloproteinase 9 (MMP-9) levels were determined by ELISA in blood samples obtained before treatment and in 30 healthy subjects. Results— HT was found in 26 patients (30%); 15 patients had hemorrhagic infarction type 1 (HI-1), 7 had HI-2, and 4 had parenchymal hemorrhage (PH). Median c-Fn concentrations were 1.3, 1.7, 4.2, 5.4, and 7.3 μg/mL in controls, non-HT, HI-1, HI-2, and PH groups, respectively (P <0.001); median MMP-9 values were 54, 87, 154, 176, and 225 ng/mL (P <0.001). Logistic regression analysis showed that only c-Fn plasma levels remained independently associated with HT after adjusting for potential confounders (OR, 2.1; 95% CI, 1.3 to 3.4; P =0.002). Similar results were obtained in the 71 patients treated within 3 hours. Conclusions— High plasma c-Fn levels are significantly associated with subsequent HT in stroke patients treated with tPA, so plasma c-Fn determinations might be useful in clinical practice to improve the risk/benefit ratio of thrombolytic treatment.

Serum Cellular Fibronectin and Matrix Metalloproteinase-9 as Screening Biomarkers for the Prediction of Parenchymal Hematoma After Thrombolytic Therapy in Acute Ischemic Stroke: A Multicenter Confirmatory Study

Background and Purpose— Plasma levels of cellular fibronectin (c-Fn) ≥3.6 μg/mL and of matrix metalloproteinase-9 (MMP-9) ≥140 ng/mL have been associated with parenchymal hematoma (PH) after treatment with tissue-type plasminogen activator (t-PA) in patients with acute ischemic stroke. In this prospective study, we sought to validate the predictive capacity of the preestablished cutoff values of these biomarkers for PH in a larger series of patients. Methods— We studied 134 patients treated with t-PA within 3 hours from symptom onset according to the SITS-MOST criteria (median time to infusion, 152 minutes; median National Institutes of Health Stroke Scale score, 14) in 4 university hospitals. Hemorrhagic transformation was classified according to the European-Australasian Acute Stroke Study II definitions on computed tomography scans performed 24 to 36 hours after treatment. Relevant hemorrhagic transformation was defined as hemorrhagic infarction type 2 or any PH. Serum c-Fn and MMP-9 levels were determined by an ELISA om blood samples obtained before treatment. Results— Cranial computed tomography showed hemorrhagic transformation in 27 patients (20%), hemorrhagic infarction in 15 (type 2 in 8 patients), and PH in 12 patients (symptomatic in 4). Serum c-Fn and MMP-9 concentrations at baseline were significantly higher in patients with relevant hemorrhagic transformation and PH than in those without (all P<0.001). The sensitivity, specificity, and positive and negative predictive values for PH by c-Fn levels ≥3.6 μg/mL were 100%, 60%, 20%, and 100%, respectively, whereas corresponding values were 92%, 74%, 26%, and 99% for MMP-9 levels ≥140 ng/mL. When both biomarkers were at levels above the cutoff points, specificity increased to 87% and the positive predictive value increased to 41%. Conclusions— This prospective study confirmed the high sensitivity and negative predictive value, with retained good specificity, of c-Fn and MMP-9 for the prediction of PH in patients treated with t-PA. Development of faster analytic methods will prove the applicability of these biomarkers in routine clinical practice.

Safety and efficacy of uric acid in patients with acute stroke (URICO-ICTUS): a randomised, double-blind phase 2b/3 trial

INTRODUCTION Uric acid is an antioxidant with neuroprotective effects in experimental models of stroke. We assessed whether uric acid therapy would improve functional outcomes at 90 days in patients with acute ischaemic stroke. METHODS URICO-ICTUS was a randomised, double-blind, placebo-controlled, phase 2b/3 trial that recruited patients with acute ischaemic stroke admitted to ten Spanish stroke centres. Patients were included if they were aged 18 years or older, had received alteplase within 4·5 h of symptom onset, and had an eligible National Institutes of Health Stroke Scale (NIHSS) score (>6 and ≤25) and premorbid (assessed by anamnesis) modified Rankin Scale (mRS) score (≤2). Patients were randomly allocated (1:1) to receive uric acid 1000 mg or placebo (both infused intravenously in 90 min during the infusion of alteplase), stratified by centre and baseline stroke severity. The primary outcome was the proportion of patients with excellent outcome (ie, an mRS score of 0-1, or 2 if premorbid score was 2) at 90 days, analysed in the target population (all randomly assigned patients who had been correctly diagnosed with ischaemic stroke and had begun study medication). The study is registered with ClinicalTrials.gov, number NCT00860366. FINDINGS Between July 1, 2011, and April 30, 2013, we randomly assigned 421 patients, of whom 411 (98%) were included in the target population (211 received uric acid and 200 received placebo). 83 (39%) patients who received uric acid and 66 (33%) patients who received placebo had an excellent outcome (adjusted risk ratio 1·23 [95% CI 0·96-1·56]; p=0·099). No clinically relevant or statistically significant differences were reported between groups with respect to death (28 [13%] patients who received uric acid vs 31 [16%] who received placebo), symptomatic intracerebral haemorrhage (nine [4%] vs six [3%]), and gouty arthritis (one [<1%] vs four [2%]). 516 adverse events occurred in the uric acid group and 532 in the placebo group, of which 61 (12%) and 67 (13%), respectively, were serious adverse events (p=0·703). INTERPRETATION The addition of uric acid to thrombolytic therapy did not increase the proportion of patients who achieved excellent outcome after stroke compared with placebo, but it did not lead to any safety concerns. FUNDING Institute of Health Carlos III of the Spanish Ministry of Health and Fundación Doctor Melchor Colet.

Wallerian Degeneration in the Corticospinal Tract Evaluated by Diffusion Tensor Imaging Correlates with Motor Deficit 30 Days after Middle Cerebral Artery Ischemic Stroke

BACKGROUND AND PURPOSE: The quantification and clinical significance of WD in CSTs following supratentorial stroke are not well understood. We evaluated the anisotropy by using DTI and signal-intensity changes on conventional MR imaging in the CST to determine whether these findings are correlated with limb motor deficit in patients with MCA ischemic stroke. MATERIALS AND METHODS: We studied 60 patients within 12 hours of stroke onset. At admission, day 3, and day 30 of evolution, patients underwent multimodal MR imaging, including DTI sequences. We assessed the severity of limb weakness by using the motor subindex scores (5a, 5b, 6a, 6b) of the m-NIHSS and established 3 groups: I (m-NIHSS scores of 0), II (m-NIHSS, 1–4), and III (m-NIHSS, 5–8). FA values and rFAs were measured on the affected and the unaffected CSTs in the pons. RESULTS: FA values for the CST were significantly lower on the affected side compared with the unaffected side only at day 30 (P < .001), and the rFA was significantly correlated with the motor deficit at day 30 (P < .001; r = −0.793). The sensitivity, specificity, and positive and negative predictive values for motor deficit by rFA < 0.925 were 95.2%, 94.9%, 90.9%, and 97.4%, respectively. CONCLUSIONS: WD in the CST revealed by DTI correlates with motor deficit 30 days after MCA ischemic stroke. This study highlights the utility of imaging follow-up at 30 days and the potential of DTI as a surrogate marker in clinical trials.

The Prediction of Malignant Cerebral Infarction by Molecular Brain Barrier Disruption Markers

Background and Purpose— Space-occupying brain edema is a life-threatening complication in patients with large hemispheric stroke. The aim of the study was to determine whether molecular markers of endothelial damage may help to predict secondary brain edema and, secondly, to identify patients who could benefit from aggressive therapies such as decompressive hemicraniectomy or hypothermia. Methods— We studied 40 consecutive patients with malignant middle cerebral artery (MCA) infarction and 35 controls with massive MCA infarctions <70 years of age and matched by stroke severity on admission. Cranial computed tomography (CT) was performed at entry and repeated between days 4 and 7, or earlier if there was neurological worsening. Malignant MCA (m-MCA) infarction was diagnosed when follow-up CT detected a more than two-thirds space-occupying MCA infarction with midline shift, compression of the basal cisterns, and neurological deterioration. Plasma concentrations of glutamate, glycine, γ-aminobutyric acid, interleukin-6 (IL-6), IL-10, tumor necrosis factor-α, matrix metalloproteinase-9 (MMP-9), and cellular-fibronectin (c-Fn) were determined in blood samples obtained at admission. Results— Mean time from stroke onset to blood sampling was 6.3±4.8 in m-MCA and 7.7±6.0 hours in the control group (P=0.63). Baseline characteristics were comparable in both groups. c-Fn and MMP-9 levels were significantly higher in patients with m-MCA than in controls (all P<0.001). c-Fn >16.6 &mgr;g/mL had the highest sensitivity (90%), specificity (100%), and negative and positive predictive values (89% and 100%, respectively) for the prediction of m-MCA infarction. Conclusions— A plasma c-Fn concentration >16.6 &mgr;g/mL at admission is associated with the development of m-MCA infarction with high sensitivity and specificity, suggesting that c-Fn might be useful in therapeutic decision making.