Value of intravenous alteplase before thrombectomy among patients with tandem lesions and emergent carotid artery stenting: A subgroup analysis of the SWIFT DIRECT trial.

BACKGROUND AND PURPOSE: The value of intravenous thrombolysis (IVT) in eligible tandem lesion patients undergoing endovascular treatment (EVT) is unknown. We investigated treatment effect heterogeneity of EVT + IVT versus EVT-only in tandem lesion patients. Additional analyses were performed for patients undergoing emergent internal carotid artery (ICA) stenting. METHODS: SWIFT DIRECT randomized IVT-eligible patients to either EVT + IVT or EVT-only. Primary outcome was 90-day functional independence (modified Rankin Scale score 0-2) after the index event. Secondary endpoints were reperfusion success, 24 h intracranial hemorrhage rate, and 90-day all-cause mortality. Interaction models were fitted for all predefined outcomes. RESULTS: Among 408 included patients, 63 (15.4%) had a tandem lesion and 33 (52.4%) received IVT. In patients with tandem lesions, 20 had undergone emergent ICA stenting (EVT + IVT: 9/33, 27.3%; EVT: 11/30, 36.7%). Tandem lesion did not show treatment effect modification of IVT on rates of functional independence (tandem lesion EVT + IVT vs. EVT: 63.6% vs. 46.7%, non-tandem lesion EVT + IVT vs. EVT: 65.6% vs. 58.2%; p for interaction = 0.77). IVT also did not increase the risk of intracranial hemorrhage  among tandem lesion patients (tandem lesion EVT + IVT vs. EVT: 34.4% vs. 46.7%, non-tandem lesion EVT + IVT vs. EVT: 33.5% vs. 26.3%; p for interaction = 0.15). No heterogeneity was noted for other endpoints (p for interaction > 0.05). CONCLUSIONS: No treatment effect heterogeneity of EVT + IVT versus EVT-only was observed among tandem lesion patients. Administering IVT in patients with anticipated emergent ICA stenting seems safe, and the latter should not be a factor to consider when deciding to administer IVT before EVT.

Predictors of symptomatic intracerebral hemorrhage after endovascular treatment for acute ischemic stroke due to tandem lesion in anterior circulation.

BACKGROUND: Endovascular treatment (EVT) of tandem lesion (TL) in the anterior circulation acute ischemic stroke (IS) usually requires periprocedural antithrombotic treatment and early initiation of dual antiplatelet therapy (DAPT) after carotid stenting. However, it may contribute to an occurrence of symptomatic intracerebral hemorrhage (SICH) in some cases. We investigated factors influencing the SICH occurrence and assessed the possible predictors of SICH after EVT. METHODS: IS patients with TL in the anterior circulation treated with EVT were enrolled in the multicenter retrospective ASCENT study. A good three-month clinical outcome was scored as 0-2 points in modified Rankin Scale (mRS) and recanalization using the TICI scale. SICH was assessed using the SITS-MOST criteria. Logistic regression analysis was used for the assessment of possible predictors of SICH with adjustment for potential confounders. RESULTS: In total, 300 (68.7 % males, mean age 67.3 ± 10.2 years) patients with median of admission NIHSS 17 were analyzed. Recanalization (TICI 2b-3) was achieved in 290 (96.7 %) patients and 176 (58.7 %) had mRS 0-2. SICH occurred in 25 (8.3 %) patients. Patients with SICH did not differ from those without SICH in the rate of periprocedural antithrombotic treatment (64 vs. 57.5 %, p = 0.526) and in the rate of DAPT started within the first 12 h after EVT (20 vs. 42.2 %, p = 0.087). After adjustment, admission NIHSS and admission glycemia were found as the only predictors of SICH after EVT. CONCLUSION: Admission NIHSS and glycemia were found as the only predictors of SICH after EVT for TL. No associations between periprocedural antithrombotic treatment, early start of DAPT after EVT and SICH occurrence were found.

Revascularization of vertebrobasilar tandem occlusions: a meta-analysis.

PURPOSE: To investigate the difference in mechanical thrombectomy (MT) outcomes between vertebrobasilar tandem occlusion (VBTO) and isolated basilar artery (BA) occlusion (non-VBTO) and the difference in rates of successful recanalization between the clean-road and dirty-road pathways, in VBTO. METHODS: We conducted a meta-analysis after searching PubMed, EMBASE, and Google Scholar databases as of April 2021. We only included adult patients who underwent MT to treat acute ischemic stroke (AIS) due to VBTO, and the following outcomes should be reported: successful recanalization, functional outcome at 90 days, and symptomatic intracerebral hemorrhage (sICH). The main effect size measures were odds ratio and risk difference, and the software used was RevMan 5.4. RESULTS: The analysis included 81 VBTO and 324 non-VBTO patients (seven studies). We found no significant difference regarding 3 m functional independence [4 studies: OR = 1.71 (95% CI, 0.54, 5.43), I2 = 75%], 3 m mortality [4 studies: OR = 1.62 (95% CI, 0.62, 4.25), I2 = 66%], sICH [4 studies: OR = 1.71 (95% CI, 0.67, 4.39), I2 = 0%], and successful recanalization [3 studies: OR = 0.81 (95% CI, 0.12, 5.57), I2 = 80%]. A subgroup analysis of 118 VBTO patients (five studies) showed no significant difference in successful recanalization between clean-road and dirty-road pathways [RD = 0.07 (95% CI, - 0.09, 0.24), I2 = 40%]. CONCLUSION: The results of this meta-analysis support the use of MT for AIS patients with VBTO. In VBTO patients, none of the clean-road or dirty-road pathways proved to be superior to the other.

Acute ischemic stroke with cervical internal carotid artery steno-occlusive lesion: multicenter analysis of endovascular approaches.

BACKGROUND: Occlusion of the internal carotid artery (ICA), whether isolated or in the setting of a tandem lesion (TL) have a poor response to treatment with intravenous thrombolysis. Previous studies ​​have demonstrated the superiority of mechanical thrombectomy in the treatment of acute ischemic stroke (AIS) following large vessel occlusion, compared to standard intravenous fibrinolysis. The aim of our study was to describe endovascular treatment (EVT) in AIS due to isolated ICA occlusion or TL. METHODS: We assessed the association between 90-day outcome and clinical, demographic, imaging, and procedure data in 51 consecutive patients with acute isolated ICA occlusion or TL who underwent EVT. We evaluated baseline NIHSS and mRS, ASPECTS, type of occlusion, stent placement, use of stent retrievers and/or thromboaspiration, duration of the procedure, mTICI, postprocedural therapy and complications. RESULTS: A favorable 90-day outcome (mRS 0-2) was achieved in 34 patients (67 %) and was significantly associated with the use of dual antiplatelet therapy after the procedure (p = 0.008), shorter procedure duration (p = 0.031), TICI 2b-3 (p < 0.001) and lack of post-procedural hemorrhagic transformation (p = 0.001). Four patients did not survive, resulting in a mortality rate of 8 %. CONCLUSIONS: Our study has shown that EVT in the treatment of AIS due to ICA occlusion is safe, and effective in determining a good functional outcome. ICA stenting led to good angiographic results and therapy with a glycoprotein IIb / IIIa inhibitor immediately after stent release did not result in a greater risk of hemorrhage. The use of post-procedural dual antiplatelet therapy was associated with favorable outcome, without a significant increase in hemorrhagic transformation.

Management of tandem occlusions in patients who receive rtPA.

BACKGROUND: Tandem occlusions exist in 17-32% of large vessel occlusion (LVO) strokes. A significant concern is bleeding when carotid stenting is performed in tandem with thrombectomy due the administration of antiplatelet agents such as glycoprotein IIb/IIIa inhibitors (GP2b3aI) after receiving rtPA, but data are limited in this setting. METHODS: A mutlicenter, retrospective chart review was conducted at two comprehensive stroke centers to assess the safety and efficacy of using GP2b3aI to facilitate carotid stent placement simultaneously with endovascular thrombectomy in patients who have received rtPA. RESULTS: Overall, 32 patients were included in this study, with average age of 66.3 ± 10.4 years and predominantly male (87.5%). The cause of stroke was mostly large artery atherosclerosis (59.4%) and the thrombectomy target vessels were typically first- or second segment middle cerebral artery (37.5% and 31.3%). Time from symptom onset to rtPA bolus was 1.8 h [interquartile range (IQR) 1.5-2.7], rtPA bolus to first pass was 2 h [IQR 1.5-3.1], rtPA bolus to GP2b3aI bolus was 2 h [IQR 1.6-3.5], and rtPA bolus to aspirin and clopidogrel administration was 4.3 h [IQR 2.6-8.9] and 6.6 h [IQR 4.5-11.6] respectively. No patients had acute in-stent thrombosis or post-op bleeding from the access site. Two patients (6.3%) had significant hemorrhagic conversion. CONCLUSION: The use of GP2b3aI in the setting of tandem occlusions that required emergent stent placement post-rtPA appears safe and effective. Given the small sample size, these findings should be interpreted cautiously, and need to be confirmed in a larger patient population.

[Stagewise treatment of tandem lesions of the internal carotid artery in patients with ischaemic stroke]. / Étapnoe lechenie tandemnogo porazheniia vnutrennei sonnoi arterii u patsientov s ishemicheskim insul'tom.

AIM: The study was aimed at assessing the results of a stagewise approach to surgical treatment of patients with ischaemic stroke and tandem lesions of coronary arteries. PATIENTS AND METHODS: We analysed the results of treating a total of 19 patients with ischaemic stroke having endured in 2017-2018 surgical interventions for tandem lesions of the internal carotid artery. All 19 patients with tandem lesions underwent as the first stage of surgical treatment recanalization of the intracranial portion of the internal carotid artery. Nine patients were subjected to thromboextraction followed by carotid stenting (Group One), ten underwent thromboextraction and carotid endarterectomy (Group Two). One patient was subjected to simultaneous endovascular intervention at the intra- and extracranial level, in 18 patients reconstruction of the internal carotid artery at the extracranial level (second stage) was performed within a postponed period (3-5 days). In the postoperative period we assessed neurological deficit and the results of 90-day survival. RESULTS: No deterioration of neurological deficit was observed after the first stage of surgical treatment. There were statistically significant differences in the degree of regression of a stagewise treatment at discharge, with predominance in the second group. The 90-day survival rate had no prevalence in either group, despite 1 lethal outcome in a patient with simultaneous thromboextraction and stenting of the extracranial portion of the internal carotid artery. CONCLUSION: Adequate prevention of haemorrhagic transformation of the damaged zone of cerebral tissue in patients with ischaemic stroke caused by tandem lesions of carotid arteries may be ensured by means of selecting stagewise treatment, i. e., postponed elimination of extracranial stenosis of the internal carotid artery. Given a small sample size, the study requires further examination and assessment of the obtained results.

[Variant of endarterectomy from common carotid artery in its total occlusion]. / Variant éndarteréktomii iz obshchei sonnoi arterii pri ee total'noi okkliuzii.

Currently, there are relatively few publications in the literature on reconstruction of the common carotid artery (CCA). CCA occlusion occurs in 2-4% of patients examined for cerebrovascular disease. Most described surgical techniques of blood flow restoration for CCA occlusions are: coronary artery bypass grafting, retrograde loop endarterectomy, endovascular and hybrid interventions. These techniques yield good remote results, however they are not devoid of disadvantages. This article describes a clinical case report concerning successful autotransplantation of the CCA in a female patient presenting with a tandem lesion: total occlusion of the right CCA and haemodynamically significant stenosis of the ostium of the right internal carotid artery (ICA). This technique is considered to be an effective method of surgical treatment of lesions of the right CCA.

A randomized pilot study of patients with tandem carotid lesions undergoing thrombectomy.

BACKGROUND AND PURPOSE: The optimal management of patients with tandem lesions (TL), or cervical internal carotid artery (c-ICA) steno-occlusive pathology and ipsilateral intracranial occlusion, who are undergoing endovascular thrombectomy (EVT) remains unknown. We sought to establish the feasibility of a trial designed to address this question. MATERIALS AND METHODS: The Endovascular Acute Stroke Intervention (EASI) study was a single-centre randomized trial comparing EVT to medical therapy for large-vessel occlusion stroke. Patients with TL receiving EVT were randomly allocated to acute c-ICA stenting or no stenting. The primary outcome was the proportion of patients with a modified Rankin Scale (mRS) score of 0-2 at 90 days. Safety outcomes were symptomatic intracranial hemorrhage (sICH) at 24hours and mortality at 90 days. RESULTS: Of 301 patients included in EASI between 2013 and 2018, 24 (8.0%) with TL were randomly allocated to acute stenting (n=13) or no stenting (n=11). Baseline characteristics were balanced. Eight (61.5%; 95% CI 35.5%-82.3%) and 7 (63.6%; 95% CI 35.4%-84.9%) patients, respectively, had a favorable outcome (mRS 0-2; P=1.0). One non-stented patient had a symptomatic intracerebral hemorrhage. CONCLUSIONS: This pilot trial of patients with TL undergoing EVT suggests that a sufficiently powered larger TL trial comparing acute c-ICA stenting to no stenting is feasible. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02157532.

Combined endovascular and surgical treatment of symptomatic tandem occlusion of common carotid artery and middle cerebral artery - case repor.

INTRODUCTION: Cerebrovascular events are among the most common causes of invalidity or death. The aim of treatment in acute cerebral ischemia is to restore the blood flow before irreversible necrosis of brain tissue and persistent neurologic deficit occur. Pharmacological, endovascular and surgical methods are employed in the treatment of these patients. CASE REPORT: The authors present a case report of a 56-year-old woman with acute cerebral ischemia caused by tandem occlusion of the left common carotid artery and the M1 segment of middle cerebral artery. In the initial phase the patient was treated by intravenous thrombolysis with minimal success. Common carotid artery was occluded and mechanical extraction of embolus was successfully performed through direct carotid bifurcation puncture. Almost complete regression of neurologic deficit occurred after the endovascular recanalization. Occluded common carotid stump and bifurcation was considered as a source of embolization and therefore, to prevent further cerebrovascular event, a subclavian-carotid bypass was performed on the 15th day after the stroke. CONCLUSION: In the reported patient with symptomatic tandem occlusion of common carotid artery and the M1 part of middle cerebral artery, recanalization of cerebral artery was attained by the combination of pharmacological and endovascular method. Consequent subclavian-to-carotid bypass was performed in tertiary prevention of further cerebrovascular event.

Initial clinical experience with the micromesh Roadsaver carotid artery stent for the treatment of patients with symptomatic carotid artery disease.

PURPOSE: To assess the effectiveness, technical aspects, handling, and safety of the micromesh Roadsaver Carotid Artery Stent in the treatment of atherosclerotic carotid artery stenosis and tandem lesions in ischemic stroke patients. METHODS: Seven patients (5 men; mean age 75±11.4 years, range 53-86) suffering from symptomatic internal carotid artery (ICA) stenosis (mean 76% diameter reduction) were treated with the dual layer closed-cell stent without embolic protection. Postdilation was performed in 6 of 7 patients. Two patients were treated in the context of ischemic stroke and concurrent middle cerebral artery occlusion. Mean National Institutes of Health Stroke Scale score at admission was 12.8±5. RESULTS: All devices were deployed satisfactorily. One wall-adherent thromboembolus in a proximal ICA was covered with the Roadsaver stent in a tandem lesion setting. The modified Rankin Scale (mRS) declined from 3.7±0.7 to 2.4±0.8 in hospital, showing an improvement in clinical symptoms. No complications were detected during or after the procedure. The 30-day mRS was 1.7±1.1. At 6 months, ultrasound examination demonstrated patency of stents and the external carotid arteries. CONCLUSION: The Roadsaver double layer micromesh stent seems to be safe and effective in the treatment of extracranial ICA stenosis and in the context of tandem lesions in ischemic stroke. Further studies with larger populations are warranted.

Safety and Efficacy of Low-Dose Eptifibatide for Tandem Occlusions in Acute Ischemic Stroke.

OBJECTIVES: The optimal treatment strategy for ischemic stroke in patients presenting with tandem occlusions of the internal carotid artery remains controversial. Several studies have demonstrated better clinical outcomes after eptifibatide, which is a short half-life antiplatelet agent. This retrospective analysis focused on the safety and efficacy of low-dose eptifibatide administration in stroke patients with tandem lesions. METHODS: We evaluated the results of endovascular treatment in 148 stroke patients with tandem lesions. Patients in whom balloon angioplasty alone resulted in satisfactory cerebral flow did not receive eptifibatide (33 patients); others received this drug together with stent implantation (115 patients). Eptifibatide was given as an intravenous bolus of 180 µg/kg and then in a modified low dose of 1 µg/kg/min for 24 hours. RESULTS: There were no statistically significant differences between both groups regarding 30-day mortality, frequency of thrombotic events, or hemorrhagic complications. An analysis of clinical status at 30-day follow-up revealed that the administration of eptifibatide was associated with a statistically significant better outcome: a higher rate of either no neurological symptoms or only mild symptoms (4 NIHSS points maximally). CONCLUSIONS: The administration of eptifibatide in stroke patients presenting with tandem lesions is relatively safe. Moreover, treatment with this drug can improve clinical outcomes in these challenging patients.

Age and Stroke Severity Matter Most for Clinical Outcome in Acute Arteriosclerotic Tandem Lesions.

Background: Tandem lesions (TLs) cause up to 15-30% of all acute ischemic strokes (AISs). Endovascular treatment (EVT) is regarded as the first-line treatment; however, uncertainties remain with respect to the treatment and predictive outcome parameters. Here, we aimed to identify the clinical and demographic factors associated with functional short- and long-term outcomes in AIS patients with arteriosclerotic TLs undergoing EVT. Methods: This was a retrospective, mono-centric cohort study of 116 consecutive AIS patients with arteriosclerotic TLs who were endovascularly treated at a stroke center, with analysis of the relevant demographic, procedural, and imaging data. Results: A total of 116 patients were included in this study, with a median age of 72 years (IQR 63-80), 31% of whom were female (n = 36). The median NIHSS on admission was 14 (IQR 7-19), with a median ASPECT score of 9 (IQR 8-10) and median NASCET score of 99% (IQR 88-100%). A total of 52% of the patients received intravenous thrombolysis. In 77% (n = 89) of the patients, an antegrade EVT approach was used, with a good recanalization (mTICI2b3) achieved in 83% of patients (n = 96). Symptomatic intracerebral hemorrhage occurred in 12.7% (n = 15) of patients. A favorable outcome (mRS0-2) and mortality at 3 months were obtained for 40% (n = 47) and 28% of patients (n = 32), respectively. Age and NIHSS on admission were strongly associated with outcome parameters. Diabetes mellitus and previous neurological disorders were independently associated with long-term mortality (median 11 months, IQR 0-42). Conclusions: Younger age, lower stroke severity, and good recanalization were found to be independently associated with a favorable outcome. In contrast, older age, higher stroke severity, previous neurological disorders, and diabetes were correlated with mortality. The endovascular treatment of acute arteriosclerotic tandem lesions is feasible and relatively safe.

Predictors of Good Clinical Outcome After Endovascular Treatment for Acute Ischemic Stroke due to Tandem Lesion in Anterior Circulation: Results from the ASCENT Study.

PURPOSE: Endovascular treatment (EVT) of tandem lesion (TL) in anterior circulation (AC) acute ischemic stroke (AIS) represents still a clinical challenge. We aimed to evaluate selected factors related to EVT and assess other possible predictors of good clinical outcome besides the generally known ones. METHODS: AIS patients with TL in AC treated with EVT were enrolled in the multicenter retrospective ASCENT study. A good three-month clinical outcome was scored as 0-2 points in modified Rankin Scale (mRS) and achieved recanalization using the TICI scale. Symptomatic intracerebral hemorrhage (SICH) was assessed using the SITS-MOST criteria. Logistic regression analysis was used for the assessment of possible predictors of mRS 0-2 with adjustment for potential confounders. RESULTS: In total, 300 (68.7% males, mean age 67.3 ± 10.2 years) patients with median of admission NIHSS 17 were analyzed. Recanalization (TICI 2b-3) was achieved in 290 (96.7%) patients and 176 (58.7%) had mRS 0-2. Besides the age, admission NIHSS and SICH, admission glycemia (p = 0.005, OR: 0.884) the stent patency within the first 30 days after EVT (p = 0.0003, OR: 0.219), dual antiplatelet therapy (DAPT) started within 12 h after EVT (p < 0.0001, OR: 5.006) and statin therapy started within 24 h after stenting (p < 0.0001, OR: 5.558) were found as other predictors. CONCLUSION: Admission glycemia, start of DAPT within 12 h and statin therapy within 24 h after EVT, and stent patency within the first 30 days after EVT were found as other predictors of good three-month clinical outcome in AIS patients treated with EVT for TL.

Immediate Carotid Artery Stenting or Deferred Treatment in Patients With Tandem Carotid Lesions Treated Endovascularly for Acute Ischaemic Stroke.

Fifteen to 20% of patients with an acute ischaemic stroke have a tandem lesion defined by the combination of an intracranial large vessel thrombo-embolic occlusion and a high grade stenosis or occlusion of the ipsilateral internal carotid artery. These patients tend to have worse outcomes than patients with isolated intracranial occlusions, with higher rates of disability and death. The introduction of endovascular thrombectomy to treat the intracranial lesion clearly improved the outcome compared with treatment with intravenous thrombolysis alone. However, the best treatment strategy for managing the extracranial carotid artery lesion in patients with tandem lesions remains unknown. Current guidelines recommend carotid endarterectomy for patients with transient ischaemic attack or non-disabling stroke and moderate or severe stenosis of the internal carotid artery, within two weeks of the initial event, to prevent major stroke recurrence and death. Alternatively, the symptomatic carotid artery could be treated by endovascular placement of a stent during endovascular thrombectomy (EVT). This would negate the need for a second procedure, immediately reduce the risk of stroke recurrence, increase patient satisfaction, and could be cost effective. However, the administration of dual antiplatelet therapy could potentially increase the risk of symptomatic intracranial haemorrhage in patients with acute ischaemic stroke. Randomised controlled trials evaluating the efficacy and safety of immediate carotid artery stenting during EVT in acute stroke patients with tandem lesions are currently ongoing and will impact the current guidelines regarding the treatment of patients with acute ischaemic stroke due to these tandem lesions.

Effects of Different Etiologies of Anterior Circulation Tandem Lesions on Short-term Prognosis of Acute Ischemic Stroke.

INTRODUCTION: The prognosis of anterior circulation tandem lesions caused by carotid artery dissection (CAD) and large artery atherosclerosis (LAA) after mechanical thrombectomy is controversial. By analyzing the clinical data of different etiologies, we explored the best treatment plan. METHODS: Clinical data of patients with anterior circulation tandem lesions admitted to the Second Affiliated Hospital of Soochow University from April 2018 to October 2021 were retrospectively collected. The Modified Rankin Scale was used as the standard to evaluate the functional prognosis of patients at 3 months. Safety assessment included symptomatic intracranial hemorrhage (sICH) and mortality. The technical evaluation of interventional procedures included operation time, successful recanalization, and times of pass. RESULTS: 74 patients were enrolled, 59 in the LAA group and 15 in the CAD group. The two groups were similar regarding the proportion of successful recanalization, the bridge treatment and the choice of surgical instruments. The puncture to recanalization time and the onset of symptoms to successful recanalization time had no significant difference (p > 0.05). There were no significant differences in hemorrhage transformation (p = 0.26), sICH (p > 0.999), good functional prognosis (p = 0.054), and mortality (p = 0.181) between the two groups. We found a trend toward a better functional outcome at 3 months in the CAD group (p = 0.054). CONCLUSION: The tandem lesions of anterior circulation caused by CAD tend to have a good functional prognosis in 3 months. The proportion of successful recanalization and surgical safety was similar between the two groups.

Diagnosis and management of tandem occlusion in acute ischemic stroke.

Approximately 20-30% of patients with acute ischemic stroke, caused by large intracranial vessel occlusion, have a tandem lesion, defined as simultaneous presence of high-grade stenosis or occlusion of the cervical internal carotid artery and thromboembolic occlusion of the intracranial terminal internal carotid artery or its branches, usually the middle cerebral artery. Patients with tandem lesions have usually worse outcomes than patients with single intracranial occlusions, and intravenous thrombolysis is less effective in these patients. Although endovascular thrombectomy is currently a cornerstone therapy in the management of acute ischemic stroke due to large vessel occlusion, the optimal management of extracranial carotid lesions in tandem occlusion remains controversial. Acute placement of a stent in the cervical carotid artery lesion is the most used therapeutic strategy compared with stented balloon angioplasty and thrombectomy alone without carotid artery revascularization; however, treatment strategies in these patients are often more complex than with single occlusion, so treatment decisions can change based on clinical and technical considerations. The aim of this review is to analyze the results of different studies and trials, investigating the periprocedural neurointerventional management of patients with tandem lesions and the safety, efficacy of the different technical strategies available as well as their impact on the clinical outcome in these patients, to strengthen current recommendations and thus optimize patient care.

Mechanical thrombectomy for middle cerebral artery occlusion caused by intracranial internal carotid artery stenosis: A case report.

Tandem internal carotid artery (ICA)/middle cerebral artery (MCA) occlusions are occasionally observed in patients with acute ischemic stroke. Most of them are caused by lesions at the origin of the ICA. In cases of intracranial ICA stenosis, the formation of a large thrombus causing MCA occlusion is extremely rare. Herein We report a case of acute MCA occlusion caused by intracranial ICA stenosis. A 62-year-old female presented with aphasia, right-side weakness, and a National Institute of Health Stroke Scale (NIHSS) score of 5. Magnetic resonance imaging (MRI) showed early ischemic infarction at the precentral gyrus. Left ICA and M1 occlusion were suspected on magnetic resonance angiography. However, the patient had complained of right-side numbness 6 days before the onset. Hence the stroke was assumed to have progressed slowly, and acute occlusion of the left ICA was eliminated as a suspected diagnosis. After admission, the symptoms worsened. MRI showed enlargement of the cerebral infarction. Computed tomography angiography showed complete occlusion of the left M1 and recanalization of the left ICA with severe stenosis of the petrous portion. The etiology of the MCA occlusion was determined to be atherothromboembolism. Percutaneous transluminal angioplasty (PTA) was performed for ICA stenosis, followed by mechanical thrombectomy (MT) for the MCA occlusion. Recanalization of the MCA was achieved. After Seven days, the NIHSS score reduced from a pre-MT assessment of 17-2. PTA followed by MT was safe and effective for treating MCA occlusion caused by intracranial ICA stenosis.

Direct Advancement of Balloon-Guide Catheter Distal to the Carotid Free-Floating Thrombus Achieves Smart Mechanical Thrombectomy.

A 68-year-old man with bladder cancer developed sudden dysarthria and left hemiplegia. MRI revealed occlusion of the right middle cerebral artery (MCA). Cerebral angiography revealed a large carotid free-floating thrombus (CFFT) at the origin of the right internal carotid artery (ICA) and right M1 occlusion. A balloon-guide catheter (BGC) was directly guided distal to the CFFT. Mechanical thrombectomy (MT) was performed on the M1 occlusion while the balloon was inflated to block antegrade blood flow, and good recanalization was achieved. To continue processing the CFFT, the deflated BGC was pulled to the common carotid artery, and the thrombus dispersed into the external carotid artery (ECA). Subsequently, the patient's symptoms improved. Directly advancing a BGC distally to a CFFT may be a useful treatment strategy for tandem lesions with carotid free-floating thrombi.

Recognition of a tandem lesion by DNA bacterial formamidopyrimidine glycosylases explored combining molecular dynamics and machine learning.

The combination of several closely spaced DNA lesions, which can be induced by a single radical hit, constitutes a hallmark in the DNA damage landscape and radiation chemistry. The occurrence of such a tandem base lesion gives rise to a strong coupling with the double helix degrees of freedom and induces important structural deformations, in contrast to DNA strands containing a single oxidized nucleobase. Although such complex lesions are known to be refractory to repair by DNA glycosylases, there is still a lack of structural evidence to rationalize these phenomena. In this contribution, we explore, by numerical modeling and molecular simulations, the behavior of the bacterial glycosylase responsible for base excision repair (MutM), specialized in excising oxidatively-damaged defects such as 7,8-dihydro-8-oxoguanine (8-oxoG). The difference in lesion recognition between a simple damage and a tandem lesion featuring an additional abasic site is assessed at atomistic resolution owing to microsecond molecular dynamics simulations and machine learning postprocessing, allowing to extensively pinpoint crucial differences in the interaction patterns of the damaged bases. Our results reveal substantial changes in the interaction network surrounding the 8-oxoG upon addition of an adjacent abasic site, leading to the perturbation of the intercalation triad which is crucial for lesion recognition and processing. The recognition process might also be impacted by a more constrained MutM-DNA binding upon tandem damage, as shown by the machine learning post-processing. This work advocates for the use of such high throughput numerical simulations for exploring the complex combinatorial chemistry of tandem DNA lesions repair and more generally local multiple damaged sites of the utmost significance in radiation chemistry.

Ostial common carotid artery occlusion and balloon-mounted stenting: Implication of embolic protection device in tandem lesion.

Ostial common carotid artery (CCA) stenosis is rare, compared to extracranial internal carotid artery bifurcation lesions. In cases of a tandem lesion, the proximal lesion usually involves the extracranial internal carotid artery, and the ostial CCA is rarely implicated. A 69-year-old woman who underwent 3 months of antiplatelet therapy for asymptomatic, right ostial, severely calcified CCA stenosis presented with sudden onset left hemiparesis. Radiographic examination revealed an ostial CCA-intracranial artery tandem lesion. After intracranial revascularization using a clot retrieval stent, we performed the endovascular treatment with a balloon-mounted stent using an embolic protection device. This procedure may be superior to others because it is possible to achieve early intracranial revascularization and prevent distal embolism during the complete treatment of proximal lesions.