scholarly journals Thrombectomy for Patients With Large Infarct Core in Practice: Where Should the Pendulum Swing?

Stroke ◽  
2021 ◽  
Author(s):  
Thabele M. Leslie-Mazwi ◽  
Dorothea Altschul ◽  
Claus Z. Simonsen
Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Jeffrey Wagner ◽  
Donald Frei ◽  
Raul Nogueira ◽  
Adnan Siddiqui ◽  
Osama O Zaidat ◽  
...  

Purpose: Mechanical thrombectomy has been demonstrated to provide benefits in the treatment of acute ischemic stroke (AIS). But whether to treat AIS patients with a large infarct core remains controversial. Although it is a common practice that patients with large infarct core are not offered endovascular treatment, previous data have consistently shown a proportion of these patients may benefit from IA intervention. The purpose of this study is to identify predictors of good outcomes in an AIS cohort with a large infarct volume previously treated with mechanical thrombectomy. Hypothesis: We hypothesize that among AIS patients with a large infarct volume, younger patients (≤66 years) who present with lower NIHSS scores will show good functional outcomes (mRS 0-2) at 90 days if treated with mechanical thrombectomy. Methods: Univariable and multivariable analyses were preformed to identify factors that predict good functional outcomes in AIS patients with ASPECTS 0-5 who were treated with the Penumbra System. Five previous prospective, multicenter trials (PIVOTAL, PICS, RetroSTART, START, SEPARATOR 3D) were included in this study. Patients who presented with symptoms of AIS were analyzed for association between presenting demographics and modified Rankin scale (mRS) score at 90 days in univariate and multivariate analyses. Results: Data for 614 patients with a median age of 69 years and an NIHSS score of 18 met study criteria. Of these, the 90-day mRS 0-2 rate and mortality were, respectively, 40.23% and 25.41%. Among those with ASPECTS 0-5 (N=93), 17.20% had good functional outcome. An age of ≤66 years was significantly associated with good outcome (p<0.0001) among those with ASPECTS 0-5. Within this age group who had ASPECTS 0-5, a baseline NIHSS score of ≤ 20 (p= 0.0088) with a target vessel location at the MCA (p=0.0210) were also strong predictors of good outcome if treated by mechanical thrombectomy. Conclusion: These data demonstrate that age ≤66 years, baseline NIHSS score of ≤ 20 with a target vessel location in the MCA are important predictors of good outcomes in an AIS cohort with a large infarct core who are eligible for mechanical thrombectomy.


1999 ◽  
Vol 19 (6) ◽  
pp. 652-660 ◽  
Author(s):  
Jaroslaw Aronowski ◽  
Ki-Hyun Cho ◽  
Roger Strong ◽  
James C. Grotta

To determine the occurrence and time-course of presumably irreversible subcellular damage after moderate focal ischemia, rats were subjected to 1, 3, 6, 9, or 24 hours of permanent unilateral middle cerebral and common carotid occlusion or 3 hours of reversible occlusion followed by 3, 6, or 21 hours of reperfusion. The topography and the extent of damage were analyzed with tetrazolium staining and immunoblot using an antibody capable of detecting breakdown of neurofilament. Neurofilament proteolysis began after 3 hours in the infarct core but was still incomplete in penumbral regions up to 9 hours. Similarly, tetrazolium-staining abnormalities were observed in the core of 50% of animals after 3 hours of ischemia. At 6 hours of permanent ischemia, infarct volume was maximal, and further prolongation of occlusion to 9 or 24 hours did not increase abnormal tetrazolium staining. In contrast to permanent ischemia and in agreement with the authors' previous demonstration of “reperfusion injury” in this model, prolongation of reperfusion from 3 hours to 6 and 21 hours after 3 hours of reversible occlusion gradually augmented infarct volume by 203% and 324%, respectively. Neurofilament proteolysis initiated approximately 3 hours after ischemia was quantitatively greatest in the core and extended during reperfusion to incorporate penumbra with a similar time course to that of tetrazolium abnormalities. These data demonstrate that, at least as measured by neurofilament breakdown and mitochondrial failure, extensive cellular damage is not present in penumbral regions for up to 9 hours, suggesting the potential for rescuing these regions by appropriate and timely neuroprotective strategies.


2020 ◽  
pp. 028418512098177
Author(s):  
Yu Lin ◽  
Nannan Kang ◽  
Jianghe Kang ◽  
Shaomao Lv ◽  
Jinan Wang

Background Color-coded multiphase computed tomography angiography (mCTA) can provide time-variant blood flow information of collateral circulation for acute ischemic stroke (AIS). Purpose To compare the predictive values of color-coded mCTA, conventional mCTA, and CT perfusion (CTP) for the clinical outcomes of patients with AIS. Material and Methods Consecutive patients with anterior circulation AIS were retrospectively reviewed at our center. Baseline collateral scores of color-coded mCTA and conventional mCTA were assessed by a 6-point scale. The reliabilities between junior and senior observers were assessed by weighted Kappa coefficients. Receiver operating characteristic (ROC) curves and multivariate logistic regression model were applied to evaluate the predictive capabilities of color-coded mCTA and conventional mCTA scores, and CTP parameters (hypoperfusion and infarct core volume) for a favorable outcome of AIS. Results A total of 138 patients (including 70 cases of good outcomes) were included in our study. Patients with favorable prognoses were correlated with better collateral circulations on both color-coded and conventional mCTA, and smaller hypoperfusion and infarct core volume (all P < 0.05) on CTP. ROC curves revealed no significant difference between the predictive capability of color-coded and conventional mCTA ( P = 0.427). The predictive value of CTP parameters tended to be inferior to that of color-coded mCTA score (all P < 0.001). Both junior and senior observers had consistently excellent performances (κ = 0.89) when analyzing color-coded mCTA maps. Conclusion Color-coded mCTA provides prognostic information of patients with AIS equivalent to or better than that of conventional mCTA and CTP. Junior radiologists can reach high diagnostic accuracy when interpreting color-coded mCTA images.


2020 ◽  
Vol 96 (2) ◽  
pp. 419-437
Author(s):  
Xiangfeng Yang

Abstract Ample evidence exists that China was caught off guard by the Trump administration's onslaught of punishing acts—the trade war being a prime, but far from the only, example. This article, in addition to contextualizing their earlier optimism about the relations with the United States under President Trump, examines why Chinese leaders and analysts were surprised by the turn of events. It argues that three main factors contributed to the lapse of judgment. First, Chinese officials and analysts grossly misunderstood Donald Trump the individual. By overemphasizing his pragmatism while downplaying his unpredictability, they ended up underprepared for the policies he unleashed. Second, some ingrained Chinese beliefs, manifested in the analogies of the pendulum swing and the ‘bickering couple’, as well as the narrative of the ‘ballast’, lulled officials and scholars into undue optimism about the stability of the broader relationship. Third, analytical and methodological problems as well as political considerations prevented them from fully grasping the strategic shift against China in the US.


Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Guangming Zhu ◽  
Patrik Michel ◽  
Amin Aghaebrahim ◽  
James T Patrie ◽  
Wenjun Xin ◽  
...  

BACKGROUND AND PURPOSE: To determine whether Perfusion-CT (PCT) adds value to Noncontrast head CT (NCT), CT-Angiogram (CTA) and clinical assessment in patients suspected of acute ischemic stroke. METHODS: We retrospectively reviewed the clinical and imaging data collected in 165 patients with acute ischemic stroke. ASPECTS score was calculated from NCT. CTA was reviewed for site of occlusion and collateral flow score. PCT was used to calculate the volumes of infarct core and ischemic penumbra on admission. Recanalization status was assessed on follow-up imaging. Clinical data included age, time from onset to baseline imaging, time from baseline imaging to reperfusion therapy, time from baseline imaging to recanalization imaging, NIHSS at baseline, treatment type and modified Rankin score (mRS) at 90 days. In a first multivariate regression analysis, we used volume of PCT penumbra and infarct core as outcome, and assessed whether they could be predicted from clinical variables, NCT and/or CTA. In a second multivariate regression analysis, we used mRS at 90 days as outcome, and determined which imaging and clinical variables predicted it best. RESULTS: 165 patients were identified. Mean±SD time from onset to baseline imaging was 6.7±8.7 hrs. 76 had a good outcome (90-day mRS 0-2), 89 had a poor outcome. Mean±SD PCT infarct was 44.8±46.5 ml. Mean±SD PCT penumbra was 47.0±33.9 ml. PCT infarct could be predicted by clinical data, NCT, CTA, and combinations of this data (P<0.05); the best predictive model included the clinical data, plus NCT and CTA. PCT Penumbra could NOT be predicted by clinical data, NCT, and CTA. In terms of predicting mRS at 90 days, all of variables but NCT and CTA were significantly associated with 90-day mRS outcome. The single most important predictor was recanalization status (P<0.001). PCT penumbra volume (P=0.001) was also a predictor of clinical outcome, especially when considered in conjunction with recanalization through an interaction term (P<0.001). CONCLUSION: PCT penumbra represents independent information, which cannot be predicted by clinical, NCT, and CTA data. PCT penumbra is an important determinant of clinical outcome, and adds relevant clinical information compared to a stroke CT work-up including NCT and CTA.


Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Bruce C Campbell ◽  
Søren Christensen ◽  
Christopher R Levi ◽  
Patricia M Desmond ◽  
Geoffrey A Donnan ◽  
...  

Background and purpose: CT-perfusion (CTP) is widely and rapidly accessible for imaging acute ischemic stroke. However, there has been limited validation of CTP parameters against the more intensively studied MRI perfusion-diffusion mismatch paradigm. We tested the correspondence of CTP with contemporaneous perfusion-diffusion MRI. Methods: Acute ischemic stroke patients <6hr after onset had CTP and perfusion-diffusion MRI within 1hr, before reperfusion therapies. Relative cerebral blood flow (relCBF) and time-to-peak of the deconvolved tissue-residue-function (Tmax) were calculated (standard singular value decomposition deconvolution). The diffusion lesion was registered to the CTP slabs and manually outlined to its maximal visual extent. CT-infarct core was defined as relCBF<31% contralateral mean as previously published using this software. The volumetric accuracy of relCBF core compared to the diffusion lesion was tested in isolation, but also when restricted to pixels with relative time-to-peak (TTP) >4sec, to reduce artifactual false positive low CBF (eg in leukoaraiosis). The MR Tmax>6sec perfusion lesion (previously validated to define penumbral tissue at risk of infarction) was automatically segmented and registered to the CTP slabs. Receiver operating characteristic (ROC) analysis determined the optimal CT-Tmax threshold to match MR-Tmax>6sec, confidence intervals generated by bootstrapping. Agreement of these CT parameters with MR perfusion-diffusion mismatch on co-registered slabs was assessed (mismatch ratio >1.2, absolute mismatch>10mL, infarct core<70mL). Results: In analysis of 98 CTP slabs (54 patients, median onset to CT 190min, median CT to MR 30min), volumetric agreement with the diffusion lesion was substantially improved by constraining relCBF<31% within the automated TTP perfusion lesion ROI (median magnitude of volume difference 9.0mL vs unconstrained 13.9mL, p<0.001). ROC analysis demonstrated the best CT-Tmax threshold to match MR-Tmax>6sec was 6.2sec (95% confidence interval 5.6-7.3sec, ie not significantly different to 6sec), sensitivity 91%, specificity 70%, AUC 0.87. Using CT-Tmax>6s “penumbra” and relCBF<31% (restricted to TTP>4s) “core”, volumetric agreement was sufficient for 90% concordance between CT and MRI-based mismatch status (kappa 0.80). Conclusions: Automated CTP mismatch classification using relCBF and Tmax is similar to perfusion-diffusion MRI. CTP may allow more widespread application of the “mismatch” paradigm in clinical practice and trials.


2005 ◽  
Vol 12 (2) ◽  
pp. S11-S11
Author(s):  
J GALCERA ◽  
I LOPEZMARTINEZ ◽  
A CABALLEROMARTINEZ ◽  
J DELAROSA ◽  
J VALENTIALDEGUER ◽  
...  

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