脑血管造影未见动脉闭塞的急性缺血性卒中

有20%～30%的急性缺血性脑卒中(AIS)患者造影时未发现任何血管闭塞。文章综述了脑血管造影未见动脉闭塞(WADO)的原因、患者发生脑梗死的风险、预后以及溶栓治疗的有效性和安全性。     

CT perfusion identifies increased salvage of tissue in patients receiving intravenous recombinant tissue plasminogen activator within 3 hours of stroke onset

BACKGROUND AND PURPOSE: In spite of the advent of thrombolytic therapy, CT-perfusion imaging is currently not fully used for clinical decision-making and not included in published clinical guidelines for management of ischemic stroke. We investigated whether lesion volumes on cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) maps predict final infarct volume and whether all these parameters are needed for triage to intravenous recombinant tissue plasminogen activator (rtPA). We also investigated the effect of intravenous rtPA on affected brain by measuring salvaged tissue volume in patients receiving intravenous rtPA and in controls.MATERIALS AND METHODS: Forty-four patients receiving intravenous rtPA and 19 controls underwent CT perfusion (CTP) studies in the emergency department within 3 hours of stroke onset. Lesion volumes were measured on MTT, CBV, and CBF maps by region-of-interest analysis and were compared with follow-up CT volumes by correlation and regression analysis. The volume of salvaged tissue was determined as the difference between the initial MTT and follow-up CT lesion volumes and was compared between intravenous rtPA-treated patients and controls.RESULTS: No significant difference between the groups was observed in lesion volume assessed from the CTP maps (P > .08). Coefficients of determination for MTT, CBF, and CBV versus follow-up CT lesion volumes were 0.3, 0.3, 0.47, with intravenous rtPA; and 0.53, 0.55, and 0.81 without intravenous rtPA. Regression of MTT on CBF lesion volumes showed codependence (R² = 0.98, P < .0001). Mean salvaged tissue volumes with intravenous rtPA were 21.8 ± 17.1 and 13.2 ± 13.5 mL in controls; these were significantly different by using nonparametric (P < .03) and Fisher exact tests (P < .04).CONCLUSIONS: Within 3 hours of stroke onset, CBV lesion volume does not necessarily represent dead tissue. MTT lesion volume alone can be used to identify the upper limit of the size of abnormally perfused brain. More brain is salvaged in patients with intravenous rtPA than in controls.

CT with physiologic imaging of cerebral perfusion (CTP) is routinely used at many centers around the world to assist in the triage of patients with acute stroke into various therapies, including intravenous thrombolysis with recombinant tissue plasminogen activator (rtPA). The use of CT in the triage process has been driven by the rapidity and wide availability of this imaging technique. Functional maps of cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) are readily constructed on a CT workstation and provide important information about the status of regional brain perfusion. Because giving intravenous rtPA is optimal within 3 hours of stroke ictus, it would be helpful to avoid spending time on those CTP parameters that do not provide critical information and to evaluate only those that directly impact the therapeutic decision.A key consideration in the assessment process of patients having acute stroke symptoms is how much affected brain tissue was already infarcted, how much is inevitably going to die, and how much could be potentially salvaged by therapy. It is this functional information that is being sought by using perfusion imaging and mapping of vascular physiology.^1-5 In the literature, it has been shown that lesion volumes on physiologic maps constructed from initial perfusion imaging in patients assessed in the 6- to 72-hour time window predict the final infarct volume.^6-9 Furthermore, several authors have shown that the volume of the initial CBV deficit approximates the final infarct size and likely represents already irreversibly infarcted tissue.^10,11Because the development of infarction is a dynamic time-dependent process, interpretation of the maps may well vary with the time from ictus. It was our aim in this study to investigate whether the lesion volumes observed on CBV, CBF, and MTT CTP maps, obtained within 3 hours of ictus, also predicted the final infarct volume and whether all these parameters are needed for triage. In addition, we investigated the effect of intravenous rtPA on affected brain tissue by measuring the final salvaged tissue volume in patients receiving intravenous rtPA and in a control group not receiving thrombolytic therapy.     

Hyperactivity of 99mTc-HMPAO within 6 hours in patients with acute ischemic stroke.

Intraarterial thrombolytic therapy has been used recently for treatment of acute ischemic stroke within 6 h after onset. Although hypoactivity of 99mTc-hexamethylpropyleneamine oxime (HMPAO) in stroke has been well documented, hyperactivity of HMPAO has not been evaluated in sufficient detail. The purpose of this study was to evaluate the incidence and clinical importance of hyperactivity of HMPAO in management of patients with acute ischemic stroke. METHODS: We retrospectively investigated HMPAO SPECT in 90 patients with acute ischemic stroke within 6 h after onset. The lesion-to-contralateral radioactivity ratios (L/Cs) were calculated on the SPECT images before treatment and were compared with the imaging results of CT or MRI (or both). RESULTS: Hyperactivity of HMPAO, accompanied by surrounding hypoactivity, was observed in 6 of 90 patients (7%) within 6 h after onset. The L/Cs ranged from 1.17 to 2.95. Two patients showed hyperactivity in the cortex and the other 4 patients showed hyperactivity in the basal ganglia. Angiography confirmed spontaneous recanalization of occluded vessels in accordance with the area of hyperactivity. In both patients with cortical hyperactivity, cerebral infarctions were revealed on follow-up CT; in 1 patient, hemorrhagic transformation developed after intraarterial thrombolytic therapy. In 3 of the 4 patients with hyperactivity in the basal ganglia, follow-up CT showed no infarction in the surrounding hypoperfused cortex (selective intraarterial thrombolytic therapy was performed on 2 patients), although various degrees of infarction were observed in the basal ganglia. Obvious infarctions developed in the basal ganglia and the cortex of the other patient. CONCLUSION: Hyperactivity of HMPAO could be seen in the basal ganglia and the cortex within 6 h after onset, reflecting spontaneous recanalization. The areas of hyperactivity may develop infarctions, whereas the accompanying areas of hypoactivity could be rescued by selective intraarterial thrombolytic therapy.     

MRI有助于预测急性脑卒中病人的首发症状时间:对不明发病时间病人的意义

目的探讨用MRI参数间接评价脑卒中发作时间的价值。材料与方法本研究经伦理委员会批准。130例已知发病时间的急性脑卒中病人在出现卒中症状12h内进行了     

Simultaneous treatment with intravenous recombinant tissue plasminogen activator and endovascular therapy for acute ischemic stroke within 3 hours of onset

BACKGROUND AND PURPOSE: Because intravenous (IV) recombinant tissue plasminogen activator (rtPA) does not always lead to a good outcome in a considerable proportion of patients, combined IV rtPA and rescue endovascular therapy (ET) have been performed in several recent studies. However, rescue therapy after completion of IV rtPA often results in late ineffective recanalization. We examined the efficacy and safety of combined IV rtPA and simultaneous ET as primary rather than rescue therapy for hyperacute middle cerebral artery (MCA) occlusion.MATERIALS AND METHODS: A total of 29 patients eligible for IV rtPA, who were diagnosed as having MCA (M1 or M2) occlusion within 3 hours of onset, underwent thrombolysis. In the combined group, patients were treated by IV rtPA (0.6 mg/kg for 60 minutes) and simultaneous ET (intra-arterial rtPA, mechanical thrombus disruption with microguidewire, and balloon angioplasty) initiated as soon as possible. In the IV group, patients were treated by IV rtPA only.RESULTS: The improvement of the National Institutes of Health Stroke Scale (NIHSS) score at 24 hours was 11 ± 4.8 in the combined group versus 5 ± 4.3 in the IV group (P < .001). In the combined group, successful recanalization was observed in 14 (88%) of 16 patients with no symptomatic intracranial hemorrhage, and 10 (63%) of 16 patients had favorable outcomes (modified Rankin Scale [mRS] 0, 1) at 3 months.CONCLUSIONS: Aggressive combined therapy with IV rtPA and simultaneous ET markedly improved the clinical outcome of hyperacute MCA occlusion without significant adverse effect. Additional randomized study is needed to confirm our results.

The principal goal in treating acute ischemic stroke is rapid recanalization of occluded arteries by thrombolysis. Patients transferred to a stroke center within 1 to 2 hours of onset might be fortunate in undergoing thrombolysis by intravenous (IV) recombinant tissue plasminogen activator (rtPA), the sole FDA-approved treatment for acute ischemic stroke within 3 hours of onset.¹ However, particularly in major arterial occlusions, the rate of early recanalization with IV rtPA is low, approximately 10% of occluded internal carotid arteries and 30% of occluded proximal middle cerebral arteries (MCA).^2,3 Accordingly, for more than two thirds of patients with major arterial occlusions, the benefit from IV rtPA is limited mainly because of unsuccessful early recanalization by IV rtPA only.Endovascular therapy (ET) such as intra-arterial thrombolysis is reported to have higher recanalization rates than IV rtPA, though effectiveness is limited by delayed initiation of treatment and recanalization.⁴ On the basis of the concept of combining the advantages of IV (quick initiation) and intra-arterial approaches (higher recanalization rate and mechanical aids to recanalization), combination therapy with use of IV rtPA and ET has been demonstrated in several studies in which encouraging results have been reported.^5-14 However, in most of the studies, additional ET was performed as a rescue therapy, after the ineffectiveness of 30- or 60-minute-IV rtPA was confirmed by MR imaging, transcranial Doppler, or angiography. Therefore, the initiation of ET was delayed by IV rtPA for 1 to 2 hours. To maximize the chances of a full neurologic recovery, occluded arteries should be recanalized as soon as possible.^1,9,14 In this study, we examined the efficacy and safety of combined therapy with IV rtPA and simultaneous ET, not as a rescue therapy, for MCA occlusion within 3 hours of onset.     

Count-based PET method for predicting ischemic stroke in patients with symptomatic carotid arterial occlusion.

PURPOSE: To test the ability of a count-based positron emission tomographic (PET) method, without arterial sampling, for the measurement of regional cerebral oxygen extraction fraction (OEF) to predict ischemic stroke in patients with symptomatic carotid arterial occlusion. MATERIALS AND METHODS: The outcome analysis of a blinded prospective study designed to determine if increased OEF was an independent predictor of stroke in patients with symptoms and with carotid occlusion was repeated by substituting a count-based method of OEF measurement for the original quantitative technique. The performance of the quantitative and count-based methods was assessed by using Kaplan-Meier cumulative survival functions (log-rank, [p < .05]). Receiver operating characteristic (ROC) curves for both methods were generated. RESULTS: Thirteen ipsilateral strokes occurred during a mean follow-up of 3.1 years for 81 patients. All ipsilateral strokes occurred in 50 patients with increased count-based OEF (P = .002, sensitivity 100%, specificity 46%). Sixty-eight patients underwent complete quantitative studies, which allowed comparison of OEF methods. Both the count-based and the quantitative methods were predictive of stroke in this subgroup (P = .005 and .025, respectively). ROC analysis demonstrated a greater area under the curve for the count-based OEF method. CONCLUSION: Count-based PET measurement of OEF without arterial sampling accurately predicts stroke in patients with carotid occlusion.     

CTA评分对发病6～24 h急性基底动脉闭塞血管内治疗临床结局的预测价值

【摘要】 目的 探讨CTA评分系统对急性基底动脉闭塞（BAO）6～24 h患者血管内治疗后早期临床结局的预测价值。方法 回顾性分析2014年1月至2019年12月在胜利油田中心医院接受血管内治疗的53例急性BAO患者临床资料。根据改良Rankin 量表（mRS）评分结果,将患者分为预后良好组（n=32）、预后不良组（n=21）。采用后循环侧支循环评分（pc-CS）、后循环（pc）-CTA侧支评分、基底动脉BATMAN评分,对血管内介入术前患者CTA影像进行评估。 结果 预后良好组、预后不良组患者年龄、取栓前和出院 NIHSS 评分、pc-CS评分、pc-CTA评分、BATMAN 评分等指标比较,差异均有统计学意义（P＜0.05）。多因素logistic回归分析显示,pc-CTA评分≤1.5分（OR=0.468,95%CI=0.231～0.946,P=0.035）、pc-CS评分≥4.5分（OR=2.183,95%CI=1.233～3.865,P=0.007）、BATMAN评分≥4.5分（OR=2.461,95%CI=1.320～4.588,P=0.005）,均为急性BAO患者血管内治疗后90 d良好临床结局的独立预测因素。受试者工作特征曲线（ROC）分析显示,pc-CS 评分、pc-CTA评分、BATMAN 评分预测良好临床结局的曲线下面积（AUC）分别为0.766（95%CI=0.632～0.901）、0.814（95%CI=0.697～0.931）、0.869（95%CI=0.763～0.975）。结论 pc-CS评分、pc-CTA 评分和BATMAN 评分均能独立有效地预测血管内治疗急性BAO患者90 d临床结局,其中反映血栓负荷及侧支代偿的BATMAN 评分似可更准确地预测预后。     

Correlation of early CT signs in the deep middle cerebral artery territories with angiographically confirmed site of arterial occlusion

BACKGROUND AND PURPOSE: Early CT signs in the deep middle cerebral artery (MCA) territories have been reported to be seen at the initial period of ischemia. We attempted to investigate the incidence of parenchymal hypodensity within 3 hours after ischemic onset among patients with angiographically proved embolic MCA occlusion and to assess the correlation of subtle hypodensity in the deep MCA territories with involvement of the lenticulostriate arteries in the presence of ischemia. METHODS: Fifty CT images obtained within 3 hours after onset of embolic MCA occlusion were retrospectively reviewed by three neurosurgeons who were aware of clinical features. Early CT signs in the deep MCA territories were divided into three grades according to their anatomic location: grade I, normal basal ganglia with hypodensity localized to the insula; grade II, partial obscuration of the posterolateral part of the putamen; and grade III, hypodensity of the entire lentiform nucleus. A grade I CT sign was considered to be a negative finding for lenticulostriate artery involvement, whereas grade II and III CT signs were considered to be positive findings. Site of occlusion and involvement of the lenticulostriate arteries were confirmed by angiography. RESULTS: Thirty-eight (76%) of 50 patients had early CT signs in the deep MCA territories. Sensitivity and specificity of a grade I CT sign indicating absence of lenticulostriate artery involvement in ischemia were 65% and 87%, respectively. On the other hand, sensitivity and specificity of grade II and grade III CT signs for presence of lenticulostriate artery involvement in ischemia were 77% and 100%, respectively. Grade II CT signs resulted from various sites of occlusion, whereas grade III was unequivocally predictive of proximal occlusion to all of the lenticulostriate arteries. CONCLUSION: Involvement of the lenticulostriate arteries may be presumed by precise evaluation of subtle, CT-revealed hypodensity in the deep MCA territories, even within 3 hours of ischemic onset.     

Endovascular arterial occlusion accomplished using microcoils deployed with and without proximal flow arrest: results in 19 patients.

BACKGROUND AND PURPOSE: Prior to their relatively recent FDA approval, detachable balloons for endovascular arterial occlusion had been available on only a limited basis. We evaluated the feasibility of permanent endovascular carotid and vertebral artery occlusion using microcoils deployed with and without proximal flow arrest in 19 patients. METHODS: Permanent endovascular occlusion was performed in 19 arteries of 19 patients. The treated lesions included nine aneurysms, one carotid-cavernous fistula/pseudoaneurysm, seven neoplasms, and two dissections. Nondetachable balloons were used to arrest proximal blood flow during occlusion of only six arteries. Anticoagulation (heparin, 5000 U IV) was used during occlusion of 18 arteries. Three to 88 coils were used per lesion. Complex fibered platinum microcoils were used for all cases, and GDCs were also used in two patients. RESULTS: Sixteen patients had no new neurologic deficits after arterial occlusion. No patient had an acute event that suggested an embolic complication. Coils provided rapid and durable arterial occlusion in 17 patients. In both patients with acute carotid artery rupture, large numbers of coils placed during flow arrest failed to produce complete occlusion, which was accomplished subsequently with detachable balloons. One of these patients incurred a fatal hemispheric infarct after occlusion. One patient treated for a ruptured posterior inferior cerebellar artery aneurysm by vertebral artery occlusion continued to have progressive neurologic deficits. One patient with a cavernous aneurysm had upper extremity weakness and mild dysphasia 24 hours after internal carotid artery occlusion. CONCLUSION: In our small series, microcoils were found to be safe and effective for neurovascular occlusion. When both intravenous heparin (5000 U IV bolus) and heparinized catheter flush solutions (5000 U/L) are used, flow arrest during coil placement is unnecessary to prevent clinically apparent embolic complications.     

无症状冠状动脉单纯心肌桥的CTA表现

目的 探讨无症状心肌桥的CT血管成像(CTA)表现.方法 回顾性分析69例无症状心肌桥的CTA资料,通过与60例有症状心肌桥的CTA表现进行对比分析.统计分析2组心肌桥的类型、发病年龄、心肌桥厚度、壁-冠状动脉长度和收缩末期直径的差异.结果 无症状浅表型心肌桥51例(74%),深埋型18例(26%);有症状对照组心肌桥浅表型和深埋型分别是13例(22%)和47例(78%);2组不同心肌桥类型发生率有统计学差异(P<0.05).2组平均发病年龄、心肌桥厚度及壁-冠状动脉的长度和直径分别是(53.01±11.17)岁,(1.25±1.16) mm,(21.33±7.32) mm,(2.86±0.45) mm和(51.36±9.31)岁,(1.45±1.87) mm,(20.07±6.60) mm,(1.37±0.41) mm.除心肌桥类型的发生率和壁-冠状动脉的直径相差显著(P<0.05)外,其他各项数据相差均不显著(P>0.05).结论 无症状单纯心肌桥多表现为浅表型,其位置和分布无特点,收缩末期壁-冠状动脉的直径是心肌桥是否出现症状的可能判断因素.     

Prognostic value of C-reactive protein levels within 6 hours after the onset of acute anterior myocardial infarction with primary PCI

Prognostic value of C-reactive protein levels within 6 hours after the onset of acute anterior myocardial infarction with primary PCI!050000$河北医科大学第二医院@刘君 !050000$河北医科大学第二医院@傅向华 !050000$河北医科大学第二医院@马宁     

Analysis of patients discharged from receiving hospitals within 24 hours of air medical transport

Introduction: Use review has become increasingly important in the current atmosphere of cost justification for air medical transport. One criterion for use review is patient discharge from receiving hospitals within 24 hours of transport. The objective of this study was to determine the frequency and characteristics of patients discharged within 24 hours of air transport; the goal was to identify particular patient types likely to be discharged soon after air transport.Methods: Flight records from November 1994 to September 1995 were reviewed. Follow-up identified patients who were discharged within 24 hours of air medical transport; these were designated the “24-hour group.” Other patients were designated the “overall group.” Comparisons between groups were made using the t test, Wilcoxon rank sum, and chi-square analysis (α = 0.05) for the following factors: age, vital signs, Glasgow coma score, percentage of intubated patients, and percentage of trauma and scene transports.Results: Of the 945 flights analyzed, 42 (4.4%) transported patients who were discharged within 24 hours of air transport. Patients in the 24-hour group were younger, less likely to be intubated, and more likely to be scene-trauma transports compared with the overall group.Conclusion: This study demonstrates that air medical transports meet currently accepted criteria for helicopter transport. This study suggests that inappropriate air medical transport is rare, even in patients discharged from receiving hospitals within 24 hours of air transport.     

Outcome of LR-3 and LR-4 observations without arterial phase hyperenhancement at Gd-EOB-DTPA-enhanced MRI follow-up

ObjectiveThe aim of this study was to retrospectively analyze the outcome of LR-3 and LR-4 without arterial phase hyperenhancement (APHE), and identify which features could predict LR-5 progression on serial Gd-EOB-DTPA-enhanced MRI follow-up.MethodsForty-nine cirrhotic patients with 55 LR-3 and 19 LR-4 without APHE were evaluated. Observations were classified as decreased, stable or increased in category at follow-up. Observation size and LI-RADS major and ancillary features were evaluated.ResultsSeventeen/fifty-five (31%) LR-3 and 8/19 (42%) LR-4 progressed to LR-5 at follow-up. Baseline LI-RADS major and ancillary features were not significantly different among LR-3 and LR-4. A diameter ≥ 10 mm significantly increased LR-5 progression risk of LR-3 (OR = 6.07; 95% CI: 0.12; 60.28]; P < .001). LR-4 with a diameter ≥ 10 mm more likely become LR-5 at follow-up (OR = 8.95; 95% CI: 0.73; 111.8; P = .083]).ConclusionLR-3 and LR-4 without APHE were often downgraded or remained stable in category on Gd-EOB-DTPA-enhanced MRI follow-up.     

Clinical and radiological outcomes of acute ischemic stroke patients without angiographic occlusion on digital subtraction angiogram. A pooled analysis of case series

Introduction  Approximately 20–30% of the patients with acute ischemic stroke do not have any occlusion demonstrated on initial digital subtraction angiography (DSA). We sought to determine the risk and rates of cerebral infarction and favorable neurological outcome in this group of acute ischemic stroke patients. Materials and methods  Patients were identified from a prospectively maintained stroke database and from literature search of MEDLINE, PubMed, and Cochrane databases. All patients had initial neurological assessment on National Institutes of Health Stroke Scale (NIHSS). Patients then underwent DSA after initial head computed tomography (CT) scans. Follow-up radiological assessment at 24–72 h was performed with CT and magnetic resonance imaging scans. Association of stroke risk factors with clinical and radiological outcomes was estimated. Results  A total of 81 patients was analyzed (mean age 63 years; 28 were women). The median NIHSS score was 8 (range 2–25). None of the patients received either intravenous or intra-arterial thrombolytic. Cerebral infarction was detected in 62 (76%) of the 81 patients. Twenty-four to 48-h NIHSS was available for 51 patients only. Neurological improvement was observed in 22 (43%) of the 51 patients. Favorable outcome ascertained at 3-month follow-up was seen in 48 (59%) of the 81 patients. After adjusting for age, sex, and baseline NIHSS, male patients [odds ratio (OR) 4.5 (1.4–14.3), p value = 0.01] and patients with age ≥65 [OR 4.3 (1.2–16.2), p value = 0.03] have a higher risk of cerebral infarcts on the follow-up imaging. Similarly, patients who presented with <10 NIHSS had a better 3-month outcome than those with >10 NIHSS [OR 0.21 (0.08–0.61), p value = 0.004]. Conclusion  Ischemic stroke patients without arterial occlusion on DSA have a higher risk of cerebral infarction and disability particularly in men, patients over 65 years of age and with NIHSS ≥10. The cause of infarction may have been arterial obstruction with spontaneous recanalization or small vessel occlusion not visible on DSA.     

深Ⅱ度烧伤伤后24小时内创面磨削的临床观察

 目的探讨深Ⅱ度烧伤伤后24h内创面行磨削术的安全性和临床疗效.方法 30例有磨削手术指征并在伤后24 h内行磨削术的深Ⅱ度烧伤患者为A组;25例磨削条件相似并按常规在伤后3～6 d行磨削术的深Ⅱ度烧伤患者为B组.比较两组休克期补液量、休克征象发生率、回吸收期的生命体征、尿量及愈合时间.结果两组患者在休克征象发生率方面差异均无统计学意义(P＞0.05);A组休克期尿量明显增多,回吸收期的体温、心率与B组明显不同,差异有统计学意义(P＜0.05或P＜0.01);A组创面平均愈合时间较B组显著缩短,差异有统计学意义(P＜0.01).结论深Ⅱ度烧伤创面于伤后24h内磨削是安全的,并能缩短创面愈合时间.     

Influence of the site of arterial occlusion on multiple baseline hemodynamic MRI parameters and post-thrombolytic recanalization in acute stroke

In this prospective MRI study, we evaluated the impact of the site of occlusion on multiple baseline perfusion parameters and subsequent recanalization in 49 stroke patients who were given intravenous tissue plasminogen activator (tPA). Pretreatment magnetic resonance angiography (MRA) revealed an arterial occlusion in 47 patients: (1) internal carotid artery (ICA) + M1 middle cerebral artery (MCA) occlusion (n=12); (2) M1 MCA occlusion (n=19); (3) M2 MCA, distal branches of the MCA and anterior cerebral artery (ACA) occlusion (n=16). Patients with ICA occlusion had significantly larger DWI, PWI and mismatch lesion volume on pretreatment MRI compared to patients with other sites of occlusion. The differences in cerebral blood flow (CBF) and peak height were significantly higher in patients with ICA occlusion compared to patients with other sites of occlusion (P=0.03 and P=0.04, respectively). Day 1 MRA showed recanalization in 28 patients (60%). The rate of recanalization was significantly different depending on the site of occlusion: 33% in ICA + M1 MCA occlusion, 63% in M1 MCA occlusion and 81% in either M2 MCA, distal branches of the MCA or ACA occlusion (P=0.002). Our data suggest that CBF and peak height are the most relevant MRI parameters to assess the severity of hemodynamic impairment in regard to the site of occlusion.     

Peripheral arterial occlusion due to COVID-19: CT angiography findings of nine patients

BackgroundReports have indicated an association of large vessel peripheral arterial occlusion in the setting of Coronavirus Disease 2019 (COVID-19). While prior investigations have mostly focused on venous or cerebral arterial occlusions, we examined patients presenting exclusively with peripheral arterial extremity occlusions to investigate for any predisposing factors in this subset of COVID-19 patients.Materials and methodsThis is a retrospective study of COVID-19 patients with peripheral arterial occlusions presenting to a multi-hospital health care system in New York City between February 1st, 2020 and April 30th, 2020. Patient data and computed tomography angiography (CTA) exams in this subset were then collected and analyzed.ResultsFor the months of February, March, and April 2020, we identified 9 patients (ages 37–93 yrs) at our health care system who underwent extremity CTA for large vessel upper or lower extremity arterial occlusion and were diagnosed with COVID-19. Patient medical histories and clinical parameters were evaluated to identify common risk factors including obesity, hypertension, hyperlipidemia, and diabetes. Patients presented with increased inflammatory markers including ferritin, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) as well as increased D-dimer.ConclusionOur findings suggest patients with COVID-19 and comorbidities presenting with elevated inflammatory markers and D-dimer may be at increased risk of large vessel peripheral arterial occlusion.     

Outcome of patients with proximal vessel occlusion of the anterior circulation and DWI-PWI mismatch is time-dependent

Background and purposePatients with ischemic stroke and large vessel occlusion are assumed to benefit from endovascular therapy (ET) independent of the symptom onset-to-treatment time (OTT) if they present with a mismatch of diffusion- and perfusion-weighted imaging (DWI-PWI mismatch). We aimed at studying the influence of OTT on clinical outcome in these patients.MethodsRetrospective database review in a tertiary care university hospital. All patients presented with proximal vessel occlusion of the anterior circulation and DWI-PWI mismatch. Primary outcome was the influence of OTT on modified Rankin scale (mRS) score three months after treatment, dichotomized in favourable (0–2) and unfavourable outcome (3–6). Secondary outcome was the effect of OTT on the shift of the mRS score. Patients treated within an early time window (< 340 min) and a late time window (≥ 340 min) were compared.Results139 patients were included. The rate of favourable outcome was significantly higher in patients who were treated in an early compared to those treated in a late time window (31 [49%] vs. 20 patients [27%], p = 0.005). Adjusted multivariate logistic regression revealed that late treatment was an independent negative predictor of favourable outcome (odds ratio 0.39, confidence interval [0.18–0.84]; p = 0.016). A shift towards higher mRS scores for late treatment was evident (p = 0.015). In sensitivity analysis, OTT remained an independent predictor when evaluated as continuous variable. These findings were confirmed in patients with a comparable DWI-PWI mismatch according to the definitions from large trials (DEFUSE 2, DEFUSE 3, SWIFT-PRIME, EXTEND-IA).ConclusionOutcome of patients with comparable DWI-PWI mismatch is time-dependent.