The purpose of this study was to determine whether leukoaraiosis (LA) predicts hemorrhagic transformation and poor outcome in patients with acute ischemic stroke treated by mechanical thrombectomy.
...We retrospectively analyzed patients with anterior circulation stroke treated with Merci devices and identified LA in the deep white matter (DWM) and periventricular white matter on the preintervention MR images. We dichotomized patients into those with moderate or severe LA in the DWM versus those without. Hemorrhage rates and outcomes were evaluated between 2 groups. We analyzed the association of moderate or severe LA with hemorrhagic transformation and poor outcome.
Twenty-six of 105 patients had moderate or severe LA in the DWM. Patients with moderate or severe LA in the DWM were older, had more severe neurological deficits and worse outcome, had higher rates of hemorrhagic transformation and parenchymal hematoma, but had equivalent rates of hemorrhagic infarct and subarachnoid hemorrhage when compared with those without. Patients with only periventricular LA did not have a higher rate of parenchymal hematoma. Moderate or severe LA in the DWM was an independent predictor of hemorrhagic transformation (OR, 3.4; P=0.019) and parenchymal hematoma (OR, 6.3; P=0.005). Patients with parenchymal hematoma were less often independent (modified Rankin Scale≤2, 3.8% versus 32.5%; P=0.003) and had greater in-hospital mortality (50% versus 10.4%; P<0.001).
Moderate or severe LA in the DWM increases the risk of parenchymal hematoma after Merci thrombectomy for patients with acute stroke. These findings require validation in a larger prospective study.
Subarachnoid hemorrhage (SAH) is a potential hemorrhagic complication after endovascular intracranial recanalization. The purpose of this study was to describe the frequency and predictors of SAH in ...acute ischemic stroke patients treated endovascularly and its impact on clinical outcome.
Acute ischemic stroke patients treated with primary mechanical thrombectomy, intra-arterial thrombolysis, or both were analyzed. Postprocedural computed tomography and magnetic resonance images were reviewed to identify the presence of SAH. We assessed any decline in the National Institutes of Health Stroke Scale score 3 hours after intervention and in the outcomes at discharge.
One hundred twenty-eight patients were treated by primary thrombectomy with MERCI Retriever devices, whereas 31 were treated by primary intra-arterial thrombolysis. Twenty patients experienced SAH, 8 with pure SAH and 12 with coexisting parenchymal hemorrhages. SAH was numerically more frequent with primary thrombectomy than in the intra-arterial thrombolysis groups (14.1% vs 6.5%, P = 0.37). On multivariate analysis, independent predictors of SAH were hypertension (odds ratio = 5.39, P = 0.035), distal middle cerebral artery occlusion (odds ratio = 3.53, P = 0.027), use of rescue angioplasty after thrombectomy (odds ratio = 12.49, P = 0.004), and procedure-related vessel perforation (odds ratio = 30.72, P < 0.001). Patients with extensive SAH or coexisting parenchymal hematomas tended to have more neurologic deterioration at 3 hours (28.6% vs 0%, P = 0.11), to be less independent at discharge (modified Rankin Scale ≤ 2; 0% vs 15.4%, P = 0.5), and to experience higher mortality during hospitalization (42.9% vs 15.4%, P = 0.29).
Procedure-related vessel perforation, rescue angioplasty after thrombectomy with MERCI devices, distal middle cerebral artery occlusion, and hypertension were independent predictors of SAH after endovascular therapy for acute ischemic stroke. Only extensive SAH or SAH accompanied by severe parenchymal hematomas may worsen clinical outcome at discharge.
Objective
Predicting hemorrhagic transformation (HT) is critical in the setting of recanalization therapy for acute stroke. Dedicated magnetic resonance imaging (MRI) sequences for detection of ...increased blood–brain barrier (BBB) permeability recently have been developed. We evaluated the ability of a novel MRI permeability technique to detect baseline derangements predictive of various forms of HT after recanalization therapy.
Methods
We retrospectively analyzed the clinical and pretreatment MRI data on patients undergoing recanalization therapy for acute cerebral ischemia at a university medical center from January 2004 to November 2006. Pretreatment MRI permeability images derived from perfusion source data were compared with posttreatment imaging to evaluate whether baseline BBB permeability derangements may predict HT after recanalization therapy. The use of a novel permeability technique to illustrate BBB derangements was based on the detection of decreased signal intensity at later time points in perfusion MRI acquisition, signifying continued local accumulation of contrast caused by leakage.
Results
Among 32 patients, some degree of HT occurred in 12. Permeability image abnormalities at baseline were present in 7 of 12 patients with HT and none of the 20 patients without HT on follow‐up images. The sensitivity of permeability abnormality for parenchymal hematoma was 83%. False‐negative findings were noted in five cases, most commonly asymptomatic or minor HT after mechanical clot retrieval.
Interpretation
Permeability images derived from pretreatment perfusion MRI source data may identify patients at risk for HT with high specificity. Our preliminary demonstration of permeability imaging based on standard perfusion data for prediction of hemorrhage merits further study with dedicated MRI BBB permeability acquisitions and multicenter validation. Ann Neurol 2007
BACKGROUND AND PURPOSE—The enrollment yield and reasons for screen failure in prehospital stroke trials have not been well delineated.
METHODS—The Field Administration of Stroke Therapy–Magnesium ...(FAST-MAG) trial identified patients for enrollment using a 2 stage screening process—paramedics in person followed by physician-investigators by cell phone. Outcomes of consecutive screening calls from paramedics to enrolling physician-investigators were prospectively recorded.
RESULTS—From 2005 to 2012, 4458 phone calls were made by paramedics to physician-investigators, an average of 1 call per vehicle every 135.7 days. A total of 1700 (38.1%) calls resulted in enrollments. The rate of enrollment of stroke mimics was 3.9%. Among the 2758 patients not enrolled, 3140 reasons for screen failure were documented. The most common reasons for nonenrollment were >2 hours from last known well (17.2%), having a prestroke condition causing disability (16.1%), and absence of a consent provider (9.5%). Novel barriers for phone informed consent specific to the prehospital setting were infrequent, but includedcell phone connection difficulties (3.2%), patient being hard of hearing (1.4%), insufficient time to complete consent (1.3%), or severely dysarthric (1.3%).
CONCLUSIONS—In this large, multicenter prehospital trial, nearly 40% of every calls from the field to physician-investigators resulted in trial enrollments. The most common reasons for nonenrollment were out of window last known well time, prestroke confounding medical condition, and absence of a consent provider.
CLINICAL TRIAL REGISTRATION—URLhttp://www.clinicaltrials.gov. Unique identifierNCT00059332.
The recent development of revascularization devices, including stent retrievers, has enabled increasingly higher revascularization rates for arterial occlusions in acute ischemic stroke. ...Patient-specific factors such as anatomy, however, may occasionally limit endovascular deployment of these new devices via the conventional transfemoral approach. We report three cases of acute ischemic stroke where a transbrachial endovascular approach to revascularization was used, resulting in successful recanalization. These examples suggest that a transbrachial approach may be considered as an alternative in the endovascular treatment of acute ischemic stroke.
Determinants of successful recanalization likely differ for Merci thrombectomy and intra-arterial pharmacological fibrinolysis interventions. Although the amount of thrombotic material to be digested ...is an important consideration for chemical lysis, mechanical debulking may be more greatly influenced by other target lesion characteristics.
In consecutive patients with acute ischemic stroke treated with Merci thrombectomy for middle cerebral artery M1 occlusions, we analyzed the influence on recanalization success and clinical outcome of target thrombus size (length) and shape (curvature and branching) on pretreatment T2* gradient echo MRI.
Among 65 patients, pretreatment MRI showed susceptibility vessel signs in 45 (69%). Thrombus length averaged 13.03 mm (range, 5.56-34.91) and irregular shape (curvature or branching) was present in 17 of 45 (38%). Presence and length of susceptibility vessel signs did not predict recanalization or good clinical outcome. Substantial recanalization (Thrombolysis In Cerebral Infarction 2b or 3) and good clinical outcome (modified Rankin Scale score ≤2) were more frequent with regular than irregular susceptibility vessel signs shape (57% versus 18%, P=0.013; 39% versus 6%, P=0.017). On multiple regression analysis, the only independent predictor of substantial recanalization was irregular susceptibility vessel signs (OR, 0.16; 95% CI, 0.04-0.69; P=0.014); and leading predictors of good clinical outcome were baseline National Institutes of Health Stroke Scale (OR, 1.20; 95% CI, 1.03-1.40; P= 0.019) and irregular susceptibility vessel signs (OR, 9.36; 95% CI, 0.98-89.4; P=0.052).
Extension of thrombus into middle cerebral artery division branches and curving shape of the middle cerebral artery stem, but not thrombus length, decrease technical and clinical success of Merci thrombectomy in M1 occlusions.
The utility of clinical measurements of impairments in glomerular barrier or filtration rate among hospitalized stroke patients without known chronic kidney disease (CKD) has not been well studied. ...We determined whether various indices of CKD would predict discharge outcomes in persons hospitalized with a recent ischemic stroke.
Presence of proteinuria and estimated low glomerular filtration rate (GFR) <60 ml/min per 1.73 m(2) on admission were assessed in consecutive ischemic stroke and transient ischemic attack patients admitted to a university hospital over 18 months, who had no history of CKD. The primary discharge outcomes assessed (among stroke patients only) were death or disability (modified Rankin Scale score > or =2) and being discharged home directly from hospital. Independent effects of CKD indices on the outcomes were evaluated using multivariable regression modeling.
Of 251 patients with recent ischemic cerebrovascular events, 198 ischemic stroke patients (79%), met the study criteria. In crude analyses, persons with proteinuria or low GFR were significantly more likely to die in the hospital (p < 0.05). After adjusting for confounders, proteinuria was independently linked with lower odds of going home directly from the hospital (OR = 0.38, 95% CI = 0.16-0.92) and poorer discharge functional status (OR = 3.19, 95% CI = 1.37-7.46), but low GFR was not independently related to either of these outcomes.
Among hospitalized ischemic stroke patients without known CKD, presence of proteinuria on admission is independently associated with poorer discharge functional activity and lower likelihood of being discharged home directly. Low GFR was not related to either outcome in these patients without known CKD.
Abstract Background Early disruption of the blood–brain barrier (BBB) due to severe ischemia can be detected by MRI T2* permeability imaging. In middle cerebral artery (MCA) infarction, pretreatment ...T2* permeability derangements have been found in 22% of patients and are powerful predictors of hemorrhagic transformation after revascularization therapy. The frequency, clinical correlates, and relation to hemorrhagic transformation of permeability derangements in posterior circulation have not been previously explored, and may differ as ischemia volume and collateral status are different between vertebrobasilar and MCA infarcts. Methods We analyzed clinical and pretreatment MRI data on consecutive patients undergoing recanalization therapy for acute vertebrobasilar ischemia at a medical center November 2001 through September 2009. Pretreatment MRI permeability images were derived from perfusion source imaging acquisitions. Permeability abnormality was detected as persisting increased signal intensity at later time points in perfusion MRI acquisition, indicating local accumulation of contrast caused by BBB leakage. Results Among the 14 patients meeting study entry criteria, mean age was 71.1 years and median pretreatment NIHSS was 20.5. Permeability imaging abnormality was present in 1 of the 14 patients (7%). Among 14 patients, post-treatment parenchymal hematoma occurred in one and more minor degrees of hemorrhagic transformation in four. The one patient with pretreatment permeability abnormality was the patient to develop post-treatment parenchymal hematoma (Fisher's exact test, P = 0.07). Conclusion Pretreatment permeability abnormality, an indicator of BBB derangements, is an infrequent finding in acute posterior circulation ischemic stroke and may be associated with an increased risk of parenchymal hematoma development undergoing recanalization therapy.
The interval appearance of cerebral microbleeds (CMBs) after endovascular treatment has never been described. We investigated the frequency and predictors of new CMBs that developed shortly after ...mechanical thrombectomy for acute ischemic stroke, and its impact on clinical outcome.We retrospectively analyzed patients with large-vessel occlusion strokes treated with Merci Retriever, Penumbra System, or stent-retriever devices. Serial T2*-weighted gradient-recall echo (GRE) magnetic resonance imaging (MRI) before and 48 h after endovascular thrombectomy were assessed to identify new CMBs. We examined independent factors associated with new CMBs after mechanical thrombectomy. We analyzed the association of the presence, burden, and distribution of new CMBs with clinical outcome.A total of 187 consecutive patients with serial GRE were enrolled in this study. CMBs were evident in 36 (19.3%) patients before mechanical thrombectomy. New CMBs occurred in 41 (21.9%) patients after mechanical thrombectomy. Of the 68 new CMBs, 45 appeared in the lobar location, 18 in the deep location and 5 in the infratentorial location. The presence of baseline CMBs was associated with new CMBs after mechanical thrombectomy (OR 5.38; 95% CI 2.13-13.59; P < 0.001), no matter whether the patients were treated primarily with mechanical thrombectomy or with intravenous thrombolysis followed by mechanical thrombectomy. Patients with new CMBs did not have increased rates of hemorrhagic transformation, in-hospital mortality, and modified Rankin Scale score 4 to 6 at discharge.New CMBs are common after mechanical thrombectomy in one-fifth of patients with acute ischemic stroke. Baseline CMBs before mechanical thrombectomy predicts the development of new CMBs. New CMBs after mechanical thrombectomy do not influence clinical outcome.
Few studies have addressed outcomes among patients ≥80 years treated with acute stroke therapy. In this study, we outline in-hospital outcomes in (1) patients ≥80 years compared with their younger ...counterparts; and (2) those over >80 years receiving intra-arterial therapy (IAT) compared with those treated with intravenous recombinant tissue-type plasminogen activator (IV rtPA).
Stroke centers within the Specialized Program of Translational Research in Acute Stroke (SPOTRIAS) prospectively collected data on all patients treated with IV rtPA or IAT from January 1, 2005, to December 31, 2010. IAT was defined as receiving any endovascular therapy; IAT was further divided into bridging therapy when the patient received both IAT and IV rtPA and endovascular therapy alone. In-hospital mortality was compared in (1) all patients aged ≥80 years versus younger counterparts; and (2) IAT, bridging therapy, and endovascular therapy alone versus IV rtPA only among those age ≥80 years using multivariable logistic regression. An age-stratified analysis was also performed.
A total of 3768 patients were included in the study; 3378 were treated with IV rtPA alone and 808 with IAT (383 with endovascular therapy alone and 425 with bridging therapy). Patients ≥80 years (n=1182) had a higher risk of in-hospital mortality compared with younger counterparts regardless of treatment modality (OR, 2.13; 95% CI, 1.60-2.84). When limited to those aged ≥80 years, IAT (OR, 0.95; 95% CI, 0.60-1.49), bridging therapy (OR, 0.82; 95% CI, 0.47-1.45), or endovascular therapy alone (OR, 1.15; 95% CI, 0.64-2.08) versus IV rtPA were not associated with increased in-hospital mortality.
IAT does not appear to increase the risk of in-hospital mortality among those aged >80 years compared with IV thrombolysis alone.
PDF
