Developments in endovascular therapy for acute ischemic stroke

Treatment for acute ischemic stroke has for years been frustrated by lack of efficacy. Despite a plethora of seemingly promising treatments from animal research, clinical application never came to fruition. Experience seems to indicate that the only truly effective treatment is the rapid restoration of perfusion to ischemic tissue prior to frank infarction. Unfortunately, every agent designed to achieve this goal met with the same ironic limitation; the ability to dissolve clot was coupled with the risk of causing intracerebral hemorrhage. Accordingly, stroke was addressed primarily through modification of risk factors and rehabilitation of the neurological sequelae. However, following the randomized trial of intravenous tissue-type plasminogen activator (t-PA) sponsored by the National Institutes of Neurological Disorders and Stroke (NINDS) in 1995, the first proven effective therapy for acute stroke became available. The door was finally open to emergency treatment of stroke in the acute phase. Moreover, the positive results of the NINDS trial appear to be independent of age. Nevertheless, intravenous thrombolysis remains ineffective in the majority of patients treated and is withheld from an even larger population because of presentation outside of the 3-hour therapeutic window. As a result, effective therapy is not available for most patients presenting with acute stroke. Recent advancements in the evaluation and treatment of acute ischemic stroke, including intra-arterial thrombolysis, mechanical thrombolysis, and combination therapies, hold significant promise for a larger proportion of patients. New imaging technology may also improve our ability to identify patients with viable brain tissue who may derive the greatest benefit from these therapies.     

急性缺血性卒中血管内治疗研究进展

急性缺血性卒中发病率、病残率和病死率均较高,是目前对人类危害最严重的疾病之一。血管内治疗已获得临床充分肯定。血管内治疗适应证的选择、治疗时间窗的确定、机械取栓装置的选择对预后至关重要。本文拟对急性缺血性卒中血管内治疗研究进展进行阐述。     

Lack of improvement following endovascular therapy in patients with acute ischemic stroke

Background: Recent randomized trials have consistently demonstrated a clinical benefit of endovascular therapy (ET) over best medical therapy (including intravenous (IV) thrombolysis in eligible patients) or IV thrombolysis only in selected patients with acute ischemic stroke (AIS) due to proximal occlusion in the carotid territory. Previous study demonstrates that lack of improvement (LOI) at 24 hours is an independent predictor of poor outcome and death at 3 months in patients with AIS treated with IV alteplase. However, LOI at 24 hours following ET has not been studied systematically. The purpose of this study is to identify predictors of LOI at 24 hours in patients with AIS after ET as well as the relationship between LOI and unfavorable outcome at 3 months. Methods: A total of 98 consecutive patients with AIS treated with ET in two separate stroke centers from 2010 to 2014 were retrospectively reviewed. Data on demographics, preexisting vascular risk factors, occlusion site, pre- and post-treatment modified Treatment in Cerebral Ischemia (mTICI) classification, collaterals and National Institutes of Health Stroke Scale (NIHSS) score on admission as well as 24 hours after the endovascular procedurals were collected. LOI was defined as a reduction of 3 points or less on the NIHSS at 24 hours compared with baseline. A 3-month functional outcome was assessed using the modified Rankin scale (mRS). Unfavorable outcome was prespecified as a score of more than 2 on the mRS. The onset-to-reperfusion time (ORT) was defined as time to mTICI 2b or 3 or end of procedure. Long ORT was defined as time to reperfusion beyond 6 hours. Poor reperfusion was defined as mTICI ≦2a. The pretreatment collateral circulation extent was graded as poor (grades 0–1) or good (grades 2–4). Results: Among the 98 patients with AIS who were treated with ET, LOI was present in 48 (49%) subjects. Multivariate analysis indicated that poor collaterals (odds ratio [OR] 3.25; 95% confidence interval [CI]: 1.29–8.19; p = 0.012) and long ORT (OR 3.97, 95% CI: 1.66–9.54; p = 0.002) were independent predictors of LOI. LOI (OR 7.18, 95% CI: 2.39–21.61; p < 0.001) was independently associated with unfavorable outcome at 3 months. Conclusion: Among patients with AIS treated with ET, as an independent predictor of unfavorable outcome, LOI at 24 hours is associated with poor collaterals and long ORT.     

Elevated troponin and ECG alterations in acute ischemic stroke and subarachnoid hemorrhage

Vascular diseases are the most common cause of death and disability in industrialised countries. Ischaemic heart disease and cerebrovascular disease frequently coexist in one patient. Therefore it is not surprising that raised troponin levels and ECG changes are detected comparatively often in acute stroke; however these changes do not always indicate myocardial infarction. Clinical and experimental data suggest that some kind of neurologically mediated myocardial injury exists--especially in subarachnoid hemorrhage--but not as a manifestation of concomitant ischaemic heart disease. This review summarises the frequency and possible pathophysiological mechanisms. In any case, raised troponin levels and ECG changes after acute stroke are of negative prognostic value, and a cardiological diagnostic work-up should be done.     

急性缺血性脑卒中血管内治疗后 症状性颅内出血的预测因素

目的 探讨急性缺血性脑卒中血管内治疗后症状性颅内出血的预测因素。方法 选取2014年1月-2017年12月因急性缺血性脑卒中至本院就诊并进行血管内治疗的患者,记录其一般情况与凝血功能,观察其治疗效果与不良反应,采用Logistic回归分析颅内出血的影响因素。结果 血管内治疗颅内出血概率为16.09%。发生颅内出血的患者平均年龄(64.46±15.47)岁,饮酒率28.57%,高血压患病率71.43%,糖尿病患病率42.86%,溶栓前抗血小板聚集药使用率64.26%,溶栓前NIHSS评分(15.63±6.84)分,溶栓前血小板计数(182.05±52.49)×10⁹/L,溶栓前INR(1.09±0.16),溶栓前收缩压(145.79±12.40)mmHg,均高于未出血组; 进一步logistic回归分析显示年龄OR=1.75(0.82～2.08),饮酒OR=0.99(0.47～1.65),高血压病OR=4.29(3.74～5.63),溶栓前NIHSS评分OR=2.81(1.46～3.26),溶栓前收缩压OR=1.45(1.15～1.93)为血管内治疗后颅内出血的危险因素(P<0.05)。结论 年龄、饮酒、高血压病、NIHSS评分溶栓前收缩压为血管内治疗颅内出血的危险因素。     

Major neurologic improvement following endovascular recanalization therapy for acute ischemic stroke

BACKGROUND: We aimed to identify the rate of major neurologic improvement (MNI) at 24 h following endovascular recanalization therapy (ERT) for acute ischemic stroke and its association with short-term outcome. METHODS: We retrospectively reviewed consecutive acute ischemic stroke patients presenting to our institution over 4 years and undergoing ERT. Angiograms were independently reviewed. Data on demographics, medical history, initial NIHSS score, 24-hour NIHSS score, site of acute vascular lesion, pre- and posttreatment Thrombolysis in Myocardial Infarction scores, symptomatic intracerebral hemorrhage (within 36 h of intervention that was associated with a 4-point decline in NIHSS score) and discharge disposition were collected. We used logistic regression analysis to identify predictors of MNI (defined as >or=8-point improvement in NIHSS or a score of 0-1 at 24 h) and favorable discharge status (defined as home or acute rehabilitation). RESULTS: Sixty-eight patients were included (median age = 71 years, 60% women, median NIHSS score = 19.5, anterior circulation = 75%). The modes of ERT were pharmacologic only (28%), mechanical only (35%) and multimodal therapy (37%). Thrombolysis in Myocardial Infarction 2 or 3 recanalization was achieved in 64.7% (mechanical only 46%, pharmacologic only 63% and multimodal 84%). The outcomes were: symptomatic intracerebral hemorrhage (11.8%), MNI (26.5%) and favorable discharge (41.2%). Age (OR = 0.93, p = 0.003) and cardioembolic stroke subtype (OR = 6.0, p = 0.018) were independent predictors of MNI. MNI was a strong predictor of favorable discharge status (OR = 46.4, p < 0.001). CONCLUSIONS: Despite initial stroke severity, MNI occurred in over one fourth of the patients and independently and strongly predicted favorable discharge outcome.     

Predictors of outcome after acute ischemic stroke

The aim of this study was to determine which variables should be the predictors for clinical outcome at discharge and sixth month after acute ischemic stroke. METHODS: Two hundred and sixty-six consecutive patients, each with an acute ischemic cerebrovascular disease, were evaluated within 24 h of symptom onset. We divided our patients into two groups; 1 - Independent (Rankin scale RS < or = 2) and, 2 - Dependent (RS>3) and death. Baseline characteristics, clinical variables, risk factors, infarct subtypes and radiologic parameters were analyzed. RESULTS: Canadian Neurological Scale (CNS) on admission <6.5 [odds ratio (OR) 22] and posterior circulation infarction (OR 4.2) were associated with a poor outcome at discharge from hospital whereas only a CNS score <6.5 (OR 14) was associated with a poor outcome at 6 months. CONCLUSIONS: Severity of neurologic deficit is the most important indicator for clinical outcome in acute ischemic stroke both at short-term and at sixth month, whereas posterior circulation infarction also predicts a poor outcome at discharge.     

Oligoclonal immunoglobulin G in acute subarachnoid hemorrhage and stroke

Oligoclonal Ig bands were found in serum and CSF of 13 of 83 patients (16%) with verified subarachnoid hemorrhage (SAH). Serum Ig bands were more common in patients with SAH than in those with cerebral ischemia. The reverse was true with oligoclonal Ig bands in CSF. These patterns suggest that there are two different mechanisms and sites of IgG synthesis: an inflammatory process after acute stage of vascular damage and a latent immunologic process--ie, polyclonal B-cell activation by injury to the brain.     

Other endovascular treatment strategies for acute ischemic stroke.

This article discusses the efforts being made to develop a safe, efficacious method of clot removal in the treatment of acute ischemic stroke. Four endovascular treatment strategies are discussed: mechanical clot disruption, endovascular thrombectomy, stents, and therapeutic carotid occlusion.     

Admission blood cell counts are predictive of stroke-associated infection in acute ischemic stroke patients treated with endovascular therapy

Neurological Sciences - Stroke-associated infection (SAI) is a major medical complication in acute ischemic stroke patients (AIS) treated with endovascular therapy (EVT). Three hundred thirty-three...     

Pre-treatment cerebral microbleeds and intracranial hemorrhage in patients with ischemic stroke receiving endovascular therapy: a systematic review and meta-analysis

Journal of Neurology - Predicting the risk of intracranial hemorrhage (ICH) is an important aspect for improving the efficacy and safety of endovascular therapy (EVT). We intended to perform a...     

急性缺血性脑卒中血管内治疗的临床研究进展

急性缺血性脑卒中发病率和致残率高,及早恢复血流有助于改善患者的预后,机械取栓因其时间窗相对宽以及血管再通率高而备受关注。机械取栓在医疗器械上经历了从MERCI取栓系统到Solitaire FR支架、Revive SE取栓器、3D支架取栓器和Penumbra系统等的改进,取栓成功率和90 d良好预后率（改良Ranking评分低于2分）逐渐得到提高。对取栓治疗失败的补救措施进行研究。而且对特殊人群（醒后卒中、儿童、高龄、妊娠）脑卒中的取栓应用也有成功使用的研究报道。总之,机械取栓能够有效开通急性闭塞的脑部大血管,从而及时恢复急性缺血脑组织的血液供应,达到改善急性缺血性脑卒中患者预后的效果。随着取栓医疗器械和技术的不断进步,效果越来越好。     

Thrombolytic therapy for acute ischemic stroke

The treatment of acute stroke changed dramatically since the publication of the NINDS trail for IV rt-PA for acute stroke. While this was not the first trial, it was the first positive trial. Subsequently there has been an explosion in acute treatment modalities since the NINDS trial showed that acute stroke treatment is feasible. The following chapter reviews the thrombolysis trials, the inclusion and exclusion criteria of intravenous and intra-arterial use of pharmacologic and mechanical thrombolysis in acute ischemic stroke. Also discussed are the new pharmacotherapies and mechanical devices that will hopefully expand the treatment window and make thrombolysis safer and more effective.