Inflammatory markers, rather than conventional risk factors, are different between carotid and MCA atherosclerosis

BACKGROUND: The apparent differences in risk factors for intra- and extracranial atherosclerosis are unclear and the mechanisms that underlie strokes in patients with intracranial atherosclerosis are not well known. We investigated the conventional vascular risk factors as well as other factors in stroke patients with large artery atherosclerosis. METHODS: Using diffusion weighted imaging (DWI) and vascular and cardiologic studies, we selected patients with acute non-cardioembolic cerebral infarcts within the middle cerebral artery (MCA) territory. Patients were divided into two groups: those with atherosclerotic lesions on the carotid sinus (n = 112) and those with isolated lesions on the proximal MCA (n = 160). Clinical features, risk factors, and DWI patterns were compared between groups. RESULTS: There were no differences in conventional risk factors, but markers for inflammation were significantly higher in patients with carotid atherosclerosis than in those with isolated MCA atherosclerosis (p < 0.01 for both). After adjustments for age/sex and the severity of stroke, an inverse correlation was observed between C-reactive protein levels and MCA atherosclerosis (odds ratio 0.57 per 1 mg/dl increase; 95% confidence interval 0.35 to 0.92; p = 0.02). Internal borderzone infarcts suggestive of haemodynamic causes were the most frequent DWI pattern in patients with MCA occlusion, whereas territorial infarcts suggesting plaque ruptures were most common in those with carotid occlusion. CONCLUSIONS: Our results indicate that inflammatory markers, rather than conventional risk factors, reveal clinical and radiological differences between patients with carotid and MCA atherosclerosis. Plaques associated with MCA atherosclerosis may be more stable than those associated with carotid atherosclerosis.     

Chronic remote ischemic conditioning for symptomatic internal carotid or middle cerebral artery occlusion: A prospective cohort study

AimsRemote ischemic conditioning (RIC) has been demonstrated to reduce recurrent stroke in patients with intracranial artery stenosis. This study aimed to evaluate the effects of RIC in patients with the symptomatic internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion.MethodsThis study is based on a high‐volume single‐center prospective cohort study in China, which included patients with symptomatic ICA or MCA occlusion with impaired hemodynamics and receiving chronic RIC. Clinical follow‐up visits were performed regularly, and cardio‐cerebrovascular events were assessed.ResultsIn total, 131 patients (68 with ICA occlusion and 63 with MCA occlusion; mean age, 52.6 ± 13.7 years; stroke, 73.5%; transient ischemic attack TIA, 26.5%) qualified for the analysis; the mean follow‐up period was 8.8 years (range, 3–14 years). The compliance of RIC was 95.6 ± 3.7%, and no associated severe adverse events happened. The annual risk of ischemic stroke and ischemic cerebrovascular events was 2.4% and 3.3%, respectively. The cumulative probabilities of ischemic cerebrovascular events and major adverse cardiovascular and cerebrovascular events were 32.8% and 44.8% at 14 years, respectively.ConclusionIn patients with symptomatic ICA or MCA occlusion with impaired hemodynamics, chronic RIC is well‐tolerated, and it appears to be associated with a low annual risk of ischemic stroke and cardio‐cerebrovascular events.     

Angiographic And Clinical Response Of Intracranial Atherosclerotic Disease Large Vessel Occlusion Stroke Undergoing Mechanical Thrombectomy

ObjectivesTo identify whether intracranial atherosclerotic disease large vessel occlusion strokes differ compared to embolic large vessel occlusion strokes in angiographic response to mechanical thrombectomy and clinical course.MethodsRetrospective analysis of acute ischemic stroke patients with large vessel occlusion, due to intracranial atherosclerotic disease or embolic etiology, who underwent mechanical thrombectomy in a primary stroke center from 11/2015 to 4/2018. We categorized patients into intracranial atherosclerotic disease or embolic large vessel occlusion based on the procedural findings. We compared pretreatment, procedural variables, and post-procedural outcomes.ResultsNinety-five patients were included, 13 with intracranial atherosclerotic disease large vessel occlusion strokes and 82 with embolic large vessel occlusion strokes. Between the two groups, there was no statistically significant difference in angiographic success (100% for intracranial atherosclerotic disease and 89% for embolic large vessel occlusion strokes); first pass success (38% for intracranial atherosclerotic disease and 34% for embolic large vessel occlusion strokes); puncture-to-first-pass time; puncture-to-recanalization time (68 minutes for intracranial atherosclerotic disease and 62 minutes for embolic large vessel occlusion strokes); number of passes; or clinical outcomes. Intracranial angioplasty was performed in 6 (46%) of intracranial atherosclerotic disease large vessel occlusion patients, and in 5 (6%) of embolic large vessel occlusion patients (p < 0.0001).ConclusionsSimilar angiographic success and procedural time metrics are achievable with intracranial atherosclerotic disease large vessel occlusion and embolic large vessel occlusion therapy. This occurred with more frequent intracranial angioplasty for intracranial atherosclerotic disease large vessel occlusion strokes.     

Pathophysiological topography of acute ischemia by combined diffusion-weighted and perfusion MRI.

BACKGROUND AND PURPOSE: Combined echoplanar MRI diffusion-weighted imaging (DWI), perfusion imaging (PI), and magnetic resonance angiography (MRA) can be used to visualize acute brain ischemia and predict lesion evolution and functional outcome. The appearance of a larger lesion by PI than by DWI quantitatively defines a mismatch of potential clinical importance. Qualitative lesion variations exist in the topographic concordance of this mismatch. We examined both the topographic heterogeneity and relative frequency of mismatched patterns in acute stroke using these MRI techniques. METHODS: Acute DWI, PI, and MRA studies of 34 prospectively recruited patients with supratentorial ischemic lesions scanned within 24 hours of stroke onset (range 2.5 to 23.3 hours, 12 patients <6 hours) were analyzed. RESULTS: Ischemic lesions were predominantly in the middle cerebral artery (MCA) territory (94%), with DWI lesions most commonly affecting the insular region. Mismatched patterns with PI lesion larger than DWI lesion occurred in 21 patients (62% overall), in all 4 patients imaged within 3 hours, and in 44% of patients imaged after 18 hours. A patient with a large PI but no DWI lesion and severe clinical deficit at 2.5 hours after stroke onset recovered completely. Regional variations in DWI and PI lesion loci were found, inferring site of proximal MCA occlusion, embolic pathogenesis, and regional arterial reperfusion. CONCLUSIONS: Analysis of the topographic concordance of PI and DWI lesions in acute stroke reveals regional PI lesions without concomitant DWI lesions, which do not necessarily progress to infarction but may suggest stroke pathogenesis and site of current arterial occlusion. Location of DWI lesions may suggest an earlier site of arterial occlusion and regions of maximal perfusion deficit.     

经颅多普勒超声评估单侧颈内动脉颅外段闭塞患者颅内侧支循环的临床意义

目的 探讨经颅多普勒超声(TCD)评估单侧颈内动脉颅外段闭塞(ICAO)患者颅内侧支循环的临床价值.方法 回顾性连续纳入2018年1月至2020年12月就诊于苏州大学附属第一医院卒中中心、行颈部血管超声检查为单侧ICAO及数字减影血管造影(DSA)证实患者145例,其中症状组109例,无症状组36例.记录TCD评估颅内...     

Transcranial Doppler 6 h after Successful Reperfusion as a Predictor of Infarct Volume

ObjectivesThe aim of the study is to analyze the hemodynamic changes in the middle cerebral artery (MCA) after endovascular revascularization in acute ischemic stroke (AIS) due to large vessel occlusion and its association with the infarct volume size in the control head CT.Materials and MethodsProspective study of patients with AIS due to internal carotid artery terminus or M1 segment of the MCA occlusion, who underwent endovascular treatment with a final TICI 2b-3 score, without concomitant stenosis ≥50% in both cervical carotid arteries. Transcranial Doppler ultrasound (TCD) of both MCAs was carried out at 6 h after the endovascular procedure. Mean flow velocities (MFV) after arterial reperfusion and its association with the infarct volume size in 24?36 h control head CT were determined.Results91 patients (51 women) were included with a median age of 78 years and National institute of Health Stroke Scale of 18. The MCA was occluded in 76.92%, and intravenous thrombolysis was administered in 40.7%. The incidence of symptomatic intracranial hemorrhage was 5.5%. At three months, mortality was 19.8% and a 52.7% of patients achieved functional independence (modified Rankin Scale 0-2). After a multivariable logistic regression analysis, an increase in the MFV greater than 50% at 6 h in the treated MCA compared to contralateral MCA, was an independent predictor of large infarct volume in the control head CT with an OR 9.615 (95%CI: 1.908?47.620), p=0.006ConclusionsIncreased MFV assessed by TCD examination following endovascular recanalization is independently associated with larger infarct volume     

A high prevalence of autoimmune indices and disorders in primary nummular headache

Background and purposeThe etiologic diagnosis of intracranial arterial occlusion is sometimes challenging because of the dynamic nature of acute stroke. We investigated whether short-term follow-up vascular imaging adds additional information to the differential diagnosis between intracranial atherosclerotic and embolic occlusion.MethodsAcute ischemic stroke patients with symptomatic middle cerebral artery (MCA) occlusion on MR angiography (MRA) within 24 h of symptom onset were included. Follow-up MRA was performed 5–7 days after stroke onset. Stroke subtypes were independently determined at baseline and follow-up MRAs based on clinical, laboratory and imaging findings.ResultsIn the 108 included patients, the most common etiologic subtype of initial stroke was intracranial large artery atherosclerosis (ICLAA) in 70 patients, followed by cardioembolism in 29 and other causes in 9. On follow-up MRA, 32 (29.6%) patients showed either significant or complete recanalization. Of these, 10 had been originally diagnosed with ICLAA, but were reclassified as a cryptogenic mechanism after follow-up MRA. Multiple logistic regression analysis showed that the presence of coexisting arterial atherosclerosis (odds ratio [OR], 6.91; 95% confidence interval [CI], 2.67–17.91; p < 0.001); the absence of large territorial infarction (OR, 4.06; 95% CI, 1.39–11.85; p = 0.010); and smoking (OR, 2.54; 95% CI, 1.028–6.29; p = 0.043) were significantly associated with a final diagnosis of ICLAA.ConclusionIn the absence of follow-up vascular imaging, a substantial proportion of patients with intracranial middle cerebral arterial occlusion may be misdiagnosed as ICLAA. Evaluation of early dynamic changes in intracranial middle cerebral arterial occlusion may provide useful information for the differential diagnosis of intrinsic atherosclerosis and embolic occlusion.     

Reduced stroke risk in patients with compromised cerebral blood flow reactivity treated with superficial temporal artery to distal middle cerebral artery bypass surgery.

Extracranial-to-intracranial (EC-IC) bypass surgery for the prevention of stroke in patients with symptomatic carotid artery occlusion has nearly ended after a randomized trial showed no benefit of the procedure. Although an EC-IC bypass might benefit patients with compromised cerebrovascular hemodynamics, the randomized trial did not differentiate patients with hemodynamic from embolic etiologies. However, subsequent investigators have identified a subgroup of patients at increased stroke risk from hemodynamic compromise. Methods: We examined the subsequent stroke rate of 42 patients with symptomatic carotid occlusion at high risk for stroke identified as having a baseline cerebral blood flow (CBF)<45 mL/100 g/min and a >5% CBF reduction in one vascular territory after a vasodilatory challenge from 1 g of intravenous acetazolamide on stable xenon-computed tomography (CT) CBF imaging. Results: Thirty patients (group 1) treated medically were a subgroup with carotid occlusion from our long-term natural history study. During a median follow-up of 12 months, 9 patients (30%) had a new stroke within a median of 5 months. Twelve patients (group 2) had recurrent, disabling cerebral ischemic symptoms, with 8 progressing to mild fixed neurological deficits from deep white matter infarction identified on CT. All were treated with superficial temporal artery to distal middle cerebral artery (STA-MCA) bypass with restoration of cerebrovascular reserve postoperatively; none had a stroke during the 18-month minimum follow-up (P=.041). Perioperative morbidity included subendocardial infarction in one and a small, asymptomatic left frontal hemorrhage in another patient. Early postoperative and delayed xenon/CT CBF studies obtained a median of 5 months postoperatively showed maintenance of cerebrovascular reserve. Conclusion: STA-MCA bypass surgery can restore cerebrovascular reserve in high-risk patients with symptomatic internal carotid artery occlusion. This was achieved with minimal perioperative complications, resulting in a subsequent reduction of stroke frequency. We suggest that the efficacy of STA-MCA bypass surgery for symptomatic carotid occlusion be re-examined prospectively using hemodynamic selection criteria.     

A dynamic concept of middle cerebral artery occlusion and cerebral infarction in the acute state based on interpreting severe hyperemia as a sign of embolic migration

The present study investigates the pathogenesis of focal cerebral hyperemia, its effect on brain tissue and discusses its pathophysiological and therapeutic importance in the light of interpreting severe hyperemia as a sign of arterial reopening probably due to embolic migration. Cerebral angiography, serial CT-scans and serial TC99 -scans were performed in a consecutive group of 73 patients with completed stroke all admitted to hospital within 3 days after stroke onset. When possible the regional cerebral blood flow (rCBF) was studied with the intracarotid Xe 133 injection method. Twenty-nine patients had evidence of middle cerebral artery (MCA) occlusion; rCBF was investigated in 24. Fourteen patients had either occlusion or severe internal carotid artery (ICA) stenosis; rCBF was not measured in these patients. Thirty patients had no angiographical evidence of MCA occlusion, ICA occlusion or severe ICA stenosis; rCBF was investigated in 24. Focal hyperemia was observed in 21 patients but exclusively in the group with evidence of MCA occlusion. Hence, these 21 patients are typical and representative for the group of patients with evidence of MCA occlusion. Hyperemia was found in infarcted as well as in non-infarcted tissue. Apparently, it is the severity of the initial ischemic episode and not the hyperemia that determines whether or not tissue necrosis develops. Interpreting severe hyperemia as a sign of arterial reopening and embolic migration (evidenced by partial reopening affecting only some MCA branches) reopening had occurred in about 1/3 of the patients with MCA occlusion before they were examined 1 to 4 days after stroke onset. Autopsy studies performed in 8 of the patients with MCA occlusion indicate that arterial reopening also takes place in many patients later on (7 of 8). According to this interpretation, hypothetical as it is, the changing position of the embolus is associated with partial or complete reperfusion leading to hyperemia in the initially ischemic brain tissue. The hemodynamic basis for appropriate therapy therefore may change from one day to the next in the acute state of stroke due to MCA occlusion.     

Association of distal hyperintense vessel sign and recurrent stroke in patients with symptomatic intracranial stenosis

ObjectiveThe distal hyperintense vessel sign (DHV) on fluid-attenuated inversion recovery magnetic resonance image (MRI) is an imaging biomarker of slow leptomeningeal collateral flow in the presence of large artery stenosis or occlusion reflecting impaired cerebral hemodynamics. In this study, we aim to investigate the significance of the DHV sign in patients with symptomatic ≥ 70% intracranial atherosclerotic stenosis.MethodsWe retrospectively reviewed patients with ischemic stroke or transient ischemic attack admitted to a single center from January 2010 to December 2017. Patients were included if they had symptomatic ≥ 70% atherosclerotic stenosis of the intracranial internal carotid artery or middle cerebral artery. The presence of the DHV sign was evaluated by blinded neuroradiologist and vascular neurologists. Recurrent ischemic stroke in the vascular territory of symptomatic intracranial artery was defined as new neurological deficits with associated neuroimaging findings during the follow up period.ResultsA total of 109 patients were included in the study, of which 55 had DHV sign. Average duration of follow up was 297 ± 326 days. Four patients were lost during follow up. Patients with the DHV sign had a higher rate of recurrent ischemic stroke (38%), compared to patients without the DHV sign (17%; p=0.018). In multivariate regression analysis, the presence of DHV sign was an independent predictor of recurrent ischemic stroke. A DHV score of ≥ 2 had a 63% sensitivity and 69% specificity for recurrent ischemic stroke.InterpretationIn patients with severe symptomatic intracranial atherosclerotic stenosis, those with a DHV sign on MRI are at higher risk of recurrent ischemic stroke.     

Absent middle cerebral artery flow predicts the presence and evolution of the ischemic penumbra

OBJECTIVES: In acute ischemic stroke the pattern of a perfusion-imaging (PI) lesion larger than the diffusion-weighted imaging (DWI) lesion may be a marker of the ischemic penumbra. We hypothesized that acute middle cerebral artery (MCA) occlusion would predict the presence of presumed "penumbral" patterns (PI > DWI), ischemic core evolution, and stroke outcome. METHODS: Echoplanar PI, DWI, and magnetic resonance angiography (MRA) were performed in 26 patients with MCA territory stroke. Imaging and clinical studies (Canadian Neurological Scale, Barthel Index, and Rankin Scale) were performed within 24 hours of onset and repeated at days 4 and 90. RESULTS: MCA flow was absent in 9 of 26 patients. This was associated with larger acute PI and DWI lesions, greater PI/DWI mismatch, early DWI lesion expansion, larger final infarct size, worse clinical outcome (p < 0.01) and provided independent prognostic information (multiple linear regression analysis, p < 0.05). Acute penumbral patterns were present in 14 of 26 patients. Most of these patients (9 of 14) had no MCA flow, whereas all nonpenumbral patients (PI < or = DWI lesion) had MCA flow (p < 0.001). Penumbral-pattern patients with absent MCA flow had greater DWI lesion expansion (p < 0.05) and worse clinical outcome (Rankin Scale score, p < 0.05). CONCLUSIONS: Absent MCA flow on MRA predicts the presence of a presumed penumbral pattern on acute PI and DWI and worse stroke outcome. Combined MRA, PI, and DWI can identify individual patients at risk of ischemic core progression and the potential to respond to thrombolytic therapy beyond 3 hours.     

Endovascular management of extracranial occlusions at the hyperacute phase of stroke with tandem occlusions

Background and purpose

The management of cervical artery occlusions in hyperacute stroke with tandem cervical/intracranial occlusions has not yet become standardized, especially when the circle of Willis is effective.

Eptifibatide use following emergent carotid stenting in acute anterior circulation ischemic stroke with tandem occlusion

BackgroundEarly revascularization of the extracranial internal carotid artery in acute anterior circulation ischemic stroke (ACIS) is feasible and may improve clinical outcome. When a stent is deployed, antithrombotic agents should be administered peri-procedurally to ensure stent patency. Our institution implemented a protocol for the use of eptifibatide as a means of maintaining stent patency in the treatment of ACIS associated with cervical internal carotid artery occlusion.MethodsOur internal database was queried for patients who received emergent endovascular therapy (ET) for ACIS with stent placement and eptifibatide administration between July 2016 and 2019.ResultsTwenty nine patients met the study criteria. The etiology was large artery atherosclerosis in 26 cases. Two patients had a dissection (7%), and one had a carotid occlusion related to a recent carotid endarterectomy. Mean NIHSS was 14. Sixteen patients received IVrtPA. Extracranial-intracranial tandem occlusion (TO) was present in 21 of cases. All patients received an eptifibatide bolus followed by an infusion for approximately 24 hours post stent deployment. Head CT was obtained prior to initiation of oral dual antiplatelet therapy with aspirin and clopidogrel. Successful recanalization was achieved in all patients with no evidence of downstream embolization. Symptomatic intracerebral hemorrhage occurred in one patient. Stent occlusion occurred in two patients, only one of which was symptomatic. Favorable clinical outcome with mRS ≤ 2 at 3 months was achieved in seventeen patients.ConclusionsThe use of eptifibatide post procedure was associated with low risk of symptomatic intracranial hemorrhage, including in patients treated with rtPA.     

Patterns of infarction in hemodynamic failure

BACKGROUND AND PURPOSE: The mechanism of stroke in patients with atherosclerotic occlusive disease and hemodynamic failure may be primarily hemodynamic or a combination of hemodynamic and embolic factors. The purpose of this study was to investigate the clinical and imaging features of stroke in these patients. METHODS: Eleven patients with complete atherosclerotic carotid artery occlusion and increased oxygen extraction fraction measured in the hemisphere distal to the occlusion developed an ischemic stroke during the observation phase of a prospective study of cerebral hemodynamics and stroke risk. The medical and study records related to the endpoint event for these 11 patients were reviewed. Records were reviewed for evidence of associated hypotension and for specific details of the neurological deficit. Infarct location was characterized, based on review of imaging and clinical features, as: (1) middle cerebral artery (MCA) core; (2) possible cortical border zone, or (3) internal border zone. RESULTS: One patient had a retinal infarction; the remaining 10 had MCA territory strokes. Six of the 10 infarctions occurred in the MCA core territory. Two of these 6 were fatal hemispheric events. One of the 10 infarctions occurred in the cortical border zone region. Two of the remaining 3 infarctions were localized to the internal border zone. One was indeterminate. CONCLUSIONS: The clinical features and radiological patterns of stroke in many patients with hemodynamic impairment failure and carotid occlusion are most consistent with large artery thromboembolic stroke. These data suggest a synergistic effect between embolic and hemodynamic mechanisms for large artery thromboembolic stroke.     

Isolated middle cerebral artery disease: clinical and neuroradiological features depending on the pathogenesis

BACKGROUND: Isolated atherosclerotic middle cerebral artery (MCA) disease is often difficult to differentiate from cardioembolic disease if intracranial atherosclerosis coexists with cardiac disease. OBJECTIVES: To evaluate whether clinical and neuroradiological features of isolated MCA disease differ according to the underlying aetiology. METHODS: Isolated MCA disease was defined as a unilateral angiographically occlusive lesion of the MCA on the symptomatic side without lesions of other intracranial or extracranial vessels. Patients with isolated MCA disease were divided into atherosclerotic and potentially cardioembolic, and the clinical, laboratory, and neuroradiological data analysed. RESULTS: Among the 850 consecutive patients with acute ischaemic stroke or transient ischaemic attack, 107 (12.6%) met the criteria for isolated MCA disease (76 with atherosclerotic disease and 31 with a potential source of cardiac embolism). Total anterior circulation infarcts were more common and baseline NIHSS score was higher in potentially embolic occlusions than in atherosclerotic disease (each p<0.001). While cortical infarcts and territorial infarcts were more common in the potential embolism group (p = 0.028 and p<0.001, respectively), subcortical border zone infarcts were more common in the atherosclerotic group (p<0.001). Multiple regression analysis showed that border zone infarcts and mild stroke were independently associated with atherosclerotic MCA disease, while territorial and cortical infarcts were associated with potential cardiac embolic disease. CONCLUSIONS: Clinical and neuroradiological characteristics can differentiate isolated atherosclerotic MCA disease from MCA disease associated with potential sources of cardiac embolism, and may reflect the differences in underlying pathogenesis.     

Endovascular treatment of acute carotid atherosclerotic tandem occlusions: Predictors of clinical outcomes as technical aspects and location of tandem occlusions

BackgroundWe aimed to analyze angiographic and clinical outcomes according to the sequence of treatment (antegrade versus retrograde) in patients with acute ischemic stroke caused by tandem extracranial cervical carotid and intracranial large vessel occlusion.Materials and methodsAll eligible tandem occlusion patients from April 2012 to March 2019 undergoing carotid artery stenting (CAS) simultaneously with intracranial endovascular thrombectomy (EVT) were retrospectively reviewed. After dividing into 2 groups according to the treatment sequence for tandem lesions (antegrade, CAS first; retrograde, intracranial EVT first), baseline data, immediate angiographic results, and clinical outcome for eligible patients were analyzed and compared. In addition, the same analysis was performed after dividing into 3 groups based on the location of intracranial lesions (T-zone, M1, M2).ResultsA total of 76 patients with a tandem occlusion (mean age, 71.7 y± 11.1) were treated with CAS and intracranial EVT. The rate of successful recanalization (TICI 2BC) was 83% (63/76), and favorable functional outcome was achieved in 49% (37/76). When comparing antegrade and retrograde methods, there were no differences in baseline data and angiographic or clinical outcomes. Favorable functional outcome was significantly higher in the M2 occlusion group (P=0.011). In multivariate analysis, baseline NIHSS <15, age <80, and M2 occlusion were revealed as independent predictors of favorable outcome.ConclusionDifferent endovascular sequences for tandem extracranial cervical carotid and intracranial large vessel occlusion do not affect angiographic or functional outcomes. Intracranial M2 occlusion, age, and baseline NIHSS were independent predictors of good clinical outcome at 3 months.     

Intra-arterial thrombolysis of embolic middle cerebral artery using collateral pathways

BACKGROUND AND PURPOSE: Cervical internal carotid artery (ICA) occlusion associated with middle cerebral artery (MCA) embolic occlusion requires prompt revascularization to prevent devastating stroke. With the advent of endovascular techniques for chemical and mechanical thrombolysis, the clinical outcome of patients with major arterial occlusions will improve. Finding the most expedient pathway to the site of end organ occlusion for thrombolysis is important. METHODS: We present two cases of acute stroke secondary to thrombotic occlusion of the cervical ICA associated with MCA embolic occlusion treated with intra-arterial thrombolysis via catheter navigation through the posterior communicating artery to the site of MCA arterial occlusion. No attempt was made to transverse the occluded ICA. RESULTS: Near complete restoration of flow was achieved in one patient and minimal vessel reopening was observed in the other patient. Both patients had good outcomes. CONCLUSION: Intra-arterial thrombolysis via Circle of Willis collaterals such as the posterior communicating artery for the treatment of acute thrombotic occlusion of the cervical internal carotid artery associated with embolic occlusion of the middle cerebral artery is a therapeutic option. This treatment option avoids the potential complications of navigating through an occluded proximal internal carotid artery and may expedite reopening of the MCA.     

Recurrence of embolic stroke in non-valvular atrial fibrillation (NVAF). An autopsy study

From 3434 consecutive autopsied cases over 60 years of age, we performed retrospective, clinicopathological examinations on 81 patients with symptomatic embolic stroke and non-valvular atrial fibrillation (NVAF) who had not received anticoagulant therapy during their lives. Twenty-one had recurrent embolic strokes (recurrence rate: 25.9%). In the thrombotic infarction without NVAF, the recurrence rate was 21.4%. Recurrent strokes occurred earlier in the embolic infarction of NVAF than in the thrombotic infarction. Most of the lesions of initial embolic strokes were present in the territory of one middle cerebral artery (MCA), while many lesions of recurrent strokes were found in the territory of the contralateral MCA. Between the NVAF cases with and without recurrent embolic stroke, there was no significant difference in the background condition such as history of hypertension, duration of NVAF, severity of cerebral arterial atherosclerosis, heart weight, intracardiac thrombi, myocardial infarctions and infarctions in other systemic organs.     

Early recurrent embolism associated with nonvalvular atrial fibrillation: a retrospective study

Nonvalvular atrial fibrillation (NVAF) can be a source of cardiogenic brain embolism. We retrospectively reviewed the clinical features of 56 patients with acute brain infarction and NVAF. Based on clinical criteria, 35 infarcts (63%) were classified as probably embolic, 13 infarcts (23%) as probably nonembolic and 8 infarcts (14%) as of indeterminate pathogenesis. Among the 35 patients with presumed embolic infarcts, 12 patients were immediately anticoagulated without hemorrhagic complications. Of 23 patients who did not receive immediate anticoagulation, three (13%) experienced recurrent embolism (one each to brain, kidney and leg) within 10 days of initial embolism. There were no early recurrent emboli in patients receiving immediate anticoagulation or patients in the nonembolic or indeterminate category. Five additional patients experienced probable brain or systemic emboli within the 11 days prior to the marker stroke event. Including these patients, 20% (8 of 40) of all NVAF patients who were not immediately anticoagulated experienced recurrent embolism within 11 days of the initial embolus. Early recurrent emboli are common in NVAF patients who experience embolic stroke.     

颈内和大脑中动脉狭窄与闭塞的梗死类型及卒中机制的研究

目的 研究单侧动脉粥样硬化性MCA/ICA狭窄与闭塞的急性缺血性脑卒中患者在DWI上的梗死类型及发病机制.方法 起病48h内DWI诊断的急性脑梗死伴有动脉粥样硬化性MCA/ICA狭窄与闭塞的131例患者,有潜在心源性栓子患者除外.急性期DWI上梗死病灶分为：（1）单发病灶（小的穿动脉梗死灶;大的穿动脉梗死灶,皮层支梗死,大面积梗死,分水岭梗死）;（2）多发梗死病灶.结果 131例患者,ICA51例,MCA80例.ICA出现最多的梗死类型：穿支动脉伴分水岭梗死,但与MCA比较,皮层支伴分水岭梗死具有统计学意义（8/51,P=0.001）.MCA以穿支动脉伴皮层支梗死最多,且与ICA比较,具有统计学意义（12/80,P=0.003）.MCA中任何皮层支梗死与狭窄程度无关,ICA中任何分水岭梗死与狭窄程度相关.结论 颈内和大脑中动脉狭窄与闭塞在DWI上的梗死类型有明显的不同,提示有着不同的卒中发病机制.