Systemic Thrombolysis in Patients With Acute Ischemic Stroke and Internal Carotid ARtery Occlusion

Evaluation of collateral circulation in patients with internal carotid artery occlusion: A clinical and ultrasonographic multicenter study

BACKGROUND

Internal carotid artery (ICA) occlusion is the major cause of ischemic stroke. The effect of collateral vessels on cerebral hemodynamics in ICA occlusion remains unclear. This study investigated the correlation between collateral vessels and the peak systolic velocity of the middle cerebral artery (MCA) in patients with ICA occlusion.

METHODS

The relevant collateral vessels included the anterior communicating (ACoA), posterior communicating (PCoA), and internal-external carotid (IECCA) arteries, respectively. Patients with unilateral ICA occlusion (n = 251) underwent transcranial Doppler imaging to detect the peak systolic velocity (PSV) of the MCA and other intracranial arteries. The clinical symptoms were assessed using the National Institutes of Health Stroke Scale (NIHSS).

RESULTS

Patients with ACoA collaterals had significantly higher PSVMCA scores and significantly lower NIHSS scores than those without ACoA collaterals (p < 0.001). Patients without any notable collaterals and those with only IECCA had the lowest PSVMCA and highest NIHSS scores. The PSVMCA and NIHSS scores were negatively correlated (r = -0.566, p < 0.001).

CONCLUSION

Collateral circulation patency in unilateral ICA occlusion was closely associated with clinical symptoms, and patients with ACoA collaterals may have favorable outcomes. (ClinicalTrials.gov Identifier: NCT02397655).

A Systematic Review of Clinical Outcomes After Carotid Artery Ligation Versus Carotid Artery Reconstruction Following Venoarterial Extracorporeal Membrane Oxygenation in Infants and Children

INTRODUCTION

In pediatric and neonatal populations, the carotid artery is commonly cannulated for venoarterial (VA) extracorporeal membrane oxygenation (ECMO). The decision to ligate (carotid artery ligation [CAL]) versus reconstruct (carotid artery reconstruction [CAR]) the artery at decannulation remains controversial as long-term neurologic outcomes remain unknown. The objective of this study was to summarize current literature on clinical outcomes following CAL and CAR after Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO).

METHODS

PubMed (MEDLINE), Embase, Web of Science, and Cochrane databases were searched using keywords from January 1950 to October 2020. Studies examining clinical outcomes following CAL and CAR for VA-ECMO in patients <18 y of age were included. Prospective and retrospective cohort studies, case series, case-control studies, and case reports were included. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were performed independently by two reviewers. Assessment of risk of bias was performed.

RESULTS

Eighty studies were included and classified into four categories: noncomparative clinical outcomes after CAL (n = 23, 28.8%), noncomparative clinical outcomes after CAR (n = 12, 15.0%), comparative clinical outcomes after CAL and/or CAR (n = 28, 35.0%), and case reports of clinical outcomes after CAL and/or CAR (n = 17, 21.3%). Follow-up ranged from 0 to 11 y. CAR patency rates ranged from 44 to 100%. There was no substantial evidence supporting an association between CAL versus CAR and short-term neurologic outcomes.

CONCLUSIONS

Studies evaluating outcomes after CAL versus CAR for VA-ECMO are heterogeneous with limited generalizability. Further studies are needed to evaluate long-term consequences of CAL versus CAR, especially as the first survivors of pediatric/neonatal ECMO approach an age of increased risk of carotid stenosis and stroke.

The efficacy of STA-MCA double anastomosis comparing to single anastomosis in chronic internal carotid artery occlusion patients

OBJECTIVE

To investigate the efficacy of STA-MCA double-anastomosis and single-anastomosis in patients with cerebral hypoperfusion caused by chronic internal carotid artery occlusion(CICAO).

METHODS

In this retrospective study, data were collected from 19 patients with CICAO who underwent STA-MCA anastomosis at our hospital between January 2016 and January 2022, and they were divided into single anastomosis group and double anastomosis group according to the surgical method. The study collected general clinical data from both groups, including age, sex, lipid levels, blood pressure, glucose levels, smoking and alcohol consumption. Additionally, pre- and postoperative neurological function, cerebral hemodynamic parameters, and postoperative ischemic events were also recorded. By combining our study findings with the existing literature, a comparative analysis of the efficacy of single- and double-anastomosis in patients with CICAO was conducted.

RESULTS

Prior to surgical treatment，there were no statistically significant differences in cerebral hemodynamic parameters, including rob (0.65 ± 0.09 VS. 0.62 ± 0.04), rut (1.73 ± 0.40 VS. 1.99 ± 0.53), and rTMax (2.02 ± 0.49 VS. 1.72 ± 0.46), as well as neurofunctional scores, including modified Rankin Scale (MRS) (2.8 ± 1.03 VS. 2.4 ± 0.88) and National Institutes of Health Stroke Scale (NIHSS) (9.1 ± 5.08 VS. 8.3 ± 4.09) between the two groups. After operation, rCBF (single: 0.65 ± 0.09 VS.0.84 ± 0.08, p = 0.007; double: 0.62 ± 0.04 VS.1.08 ± 0.20, p = 0.001) were significantly increased in both groups, but the rMTT (1.99 ± 0.53 VS.1.27 ± 0.42, p = 0.0447) and rTMax (1.72 ± 0.46 VS.1.16 ± 0.16, p = 0.038) showed significant differences postoperatively only in the double-anastomosis group. The MRS (single: 1.8 ± 1.23, double: 1.7 ± 0.9) in both groups and the NIHSS (7.2 ± 5.11) in single-anastomosis group were not improved after surgery, while the NIHSS (8.3 ± 4.09 VS.4.4 ± 3.08, p = 0.037) in double-anastomosis group was improve significantly. In summary, the double-anastomosis group showed better improvement in rCBF and NIHSS scores compared to the single-anastomosis group.(ΔrCBF: 0.19±0.09 VS. 0.45±0.18, p=0.02, ΔNIHSS: 1.9±0.56 VS. 4±1.73, p=0.002). The cases were followed up for 20.3 ± 18.6 months, and there were no ischemic events in either group during the follow-up period.

CONCLUSION

STA-MCA revascularization can improve CBF in patients with hypoperfusion caused by CICAO, and prevent the reoccurrence of ischemic stroke effectively. Compared with single-anastomosis, double-anastomosis can provide more CBF and improve neurologic dysfunction.

Mechanical thrombectomy via direct carotid artery approach for the treatment of acute anterior circulation large vessel occlusion

Background

Mechanical thrombectomy (MT) has become an important treatment method for acute anterior circulation large vessel occlusion. The carotid artery approach is a fast and effective alternative when the transfemoral approach is difficult due to vascular variation. The present study reports on seven cases of acute anterior circulation stroke where direct carotid approach was used to obtain vascular access.

Methods and materials

Patients with acute anterior circulation large vessel occlusion treated via carotid artery access between January 2018 and January 2020 were retrospectively analyzed. Brain computed tomography (CT) and angiographic imaging results, indications for carotid artery approach and technical aspects of the method, modified thrombolysis in cerebral infarction (mTICI), procedure-related complications, and patient outcomes were evaluated.

Results

Seven patients were treated using a direct carotid artery approach. Among the seven cases, four patients were treated using percutaneous carotid artery puncture, and two patients were treated with emergency carotid artery incision and thrombectomy. The remaining case involved carotid artery puncture for MCA thrombectomy, followed by carotid artery incision for carotid artery thrombectomy. The carotid artery puncture point was exposed via surgical incision and sutured after MT. Modified Rankin Scale (MRS) scores 90 days after surgery showed good prognosis in three patients, poor prognosis in four patients.

Conclusion

This case series highlights the advantage of using a transcarotid approach to bypass anatomical barriers to achieve faster reperfusion when the femoral approach is not possible. The carotid artery puncture point was surgically exposed and sutured to reduce the incidence of postoperative complications.

Urgent Endarterectomy for Symptomatic Carotid Occlusion is Associated with a High Mortality

OBJECTIVE

Interventions for carotid occlusions are infrequently undertaken and the outcomes are poorly defined. We sought to study patients undergoing urgent carotid revascularization for symptomatic occlusions.

METHODS

The Society for Vascular Surgery Vascular Quality Initiative database was queried from 2003 to 2020 to identify patients with carotid occlusions undergoing carotid endarterectomy (CEA). Only symptomatic patients undergoing urgent interventions within 24 hours of presentation were included. Patients were identified based on CT and MRI imaging. This cohort was compared to symptomatic patients undergoing urgent intervention for severe stenosis (≥80%). Primary endpoints were perioperative stroke, death, myocardial infarction (MI) and composite outcomes as defined by the SVS reporting guidelines. Patient characteristics were analyzed to determine predictors of perioperative mortality and neurological events.

RESULTS

390 patients who underwent urgent CEA for symptomatic occlusions were identified. The mean age was 67.4±10.2 years (range 39 to 90 years). The cohort was predominantly male (60%) with associated risk factors for cerebrovascular disease, including hypertension (87.4%), diabetes (34.4%), coronary artery disease (21.6%) and current smoking (38.7%). This population had high utilization of medications including statin (78.6%), P2Y₁₂ inhibitor (32.0%), aspirin (77.9%) and renin-angiotensin inhibitor (43.7%) preoperatively. When compared to patients undergoing urgent endarterectomy for severe stenosis (≥80%), those with symptomatic occlusion were well matched with regards to risk factors, but the severe stenosis cohort appeared better medically managed and less likely to present with cortical stroke symptoms. Perioperative outcomes were significantly worse for the carotid occlusion cohort, primarily driven by higher perioperative mortality (2.8% vs 0.9%, P<.001). The composite endpoint of stroke/death/MI was also significantly worse in the occlusion cohort (7.7% vs 4.9%, P=.014). On multivariate analysis, carotid occlusion was associated with increased mortality (OR, 3.028; 95% CI, 1.362-6.730; P=.007) and composite outcome of stroke, death, or MI (OR, 1.790; 95% CI, 1.135-2.822, P=.012).

CONCLUSIONS

Revascularization for symptomatic carotid occlusion constitutes approximately 2% of carotid interventions captured in the VQI, affirming the rarity of this undertaking. These patients have acceptable rates of perioperative neurologic events but are at an elevated risk of overall perioperative adverse events, primarily driven by higher mortality, compared to those with severe stenosis. Carotid occlusion appears to be the most significant risk factor for the composite endpoint of perioperative stroke, death, or MI. While intervention for a symptomatic carotid occlusion may be performed with acceptable rate of perioperative complications, judicious patient selection is warranted in this high-risk cohort.

Recanalization Rate and Clinical Outcomes of Intravenous Tissue Plasminogen Activator Administration for Large Vessel Occlusion Stroke Patients

OBJECTIVE

Stroke caused from large vessel occlusion (LVO) has emerged as the most common stroke subtype worldwide. Intravenous tissue plasminogen activator administration (IV-tPA) and additional intraarterial thrombectomy (IA-Tx) is regarded as standard treatment. In this study, the authors try to find the early recanalization rate of IV-tPA in LVO stroke patients.

METHODS

Total 300 patients undertook IA-Tx with confirmed anterior circulation LVO, were analyzed retrospectively. Brain computed tomography angiography (CTA) was the initial imaging study and acute stroke magnetic resonance angiography (MRA) followed after finished IV-tPA. Early recanalization rate was evaluated by acute stroke MRA within 2 hours after the IV-tPA. In 167 patients undertook IV-tPA only and 133 non-recanalized patients by IV-tPA, additional IA-Tx tried (IV-tPA + IA-Tx group). And 131 patients, non-recanalized by IV-tPA (IV-tPA group) additional IA-Tx recommend and tried according to the patient condition and compliance.

RESULTS

Early recanalization rate of LVO after IV-tPA was 12.0% (36/300). In recanalized patients, favorable outcome (modified Rankin Scale, 0-2) was 69.4% (25/36) while it was 32.1% (42/131, p<0.001) in non-recanalized patients. Among 133 patients, nonrecanalized after intravenous recombinant tissue plasminogen activator and undertook additional IA-Tx, the clinical outcome was better than not undertaken additional IA-Tx (favorable outcome was 42.9% vs. 32.1%, p=0.046). Analysis according to the perfusion/diffusion (P/D)-mismatching or not, in patient with IV-tPA with IA-Tx (133 patients), favorable outcome was higher in P/ D-mismatching patient (52/104; 50.0%) than P/D-matching patients (5/29; 17.2%; p=0.001). Which treatment tired, P/D-mismatching was favored in clinical outcome (iv-tPA only, p=0.008 and IV-tPA with IA-Tx, p=0.001).

CONCLUSION

The P/D-mismatching influences on the recanalization and clinical outcomes of IV-tPA and IA-Tx. The authors would like to propose that we had better prepare IA-Tx when LVO is diagnosed on initial diagnostic imaging. Furthermore, if the patient shows P/D-mismatching on MRA after IV-tPA, additional IA-Tx improves treatment results and lessen the futile recanalization.

Direct Mechanical Thrombectomy Versus Prior Bridging Intravenous Thrombolysis in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

The current guideline recommends using an intravenous tissue-type plasminogen activator (IV tPA) prior to mechanical thrombectomy (MT) in eligible acute ischemic stroke (AIS) with emergent large vessel occlusion (ELVO). Some recent studies found no significant differences in the long-term functional outcomes between bridging therapy (BT, i.e., IV tPA prior to MT) and direct MT (dMT).

METHODS

We conducted a systematic review and meta-analysis to compare the safety and functional outcomes between BT and dMT in AIS patients with ELVO who were eligible for IV tPA administration. Based on the ELVO location, patients were categorized as the anterior group (occlusion of the anterior circulation), or the combined group (occlusion of the anterior and/or posterior circulation). A subgroup analysis was performed based on the study type, i.e., RCT and non-RCT.

RESULTS

Thirteen studies (3985 patients) matched the eligibility criteria. Comparing the BT and dMT groups, no significant differences in terms of mortality and good functional outcome were observed at 90 days. Symptomatic intracranial hemorrhagic (sICH) events were more frequent in BT patients in the combined group (OR = 0.73, p = 0.02); this result remained significant only in the non-RCT subgroup (OR = 0.67, p = 0.03). The RCT subgroup had a significantly higher rate of successful revascularization in BT patients (OR = 0.73, p = 0.02).

CONCLUSIONS

Our meta-analysis uncovered no significant differences in functional outcome and mortality rate at 90 days between dMT and BT in patients with AIS who had ELVO. Although BT performed better in terms of successful recanalization rate, there is a risk of increased sICH rate in this group.

Utility of tPA Administration in Acute Treatment of Internal Carotid Artery Occlusions

Background

Intravenous tissue plasminogen activator (IV-tPA) remains part of the guidelines for acute ischemic stroke treatment, yet internal carotid artery occlusions (ICAO) are known to be poorly responsive to IV-tPA. It is unknown whether bridging thrombolysis (BT) is beneficial in such cases.

Purpose

We sought to evaluate whether the use of IV-tPA improved overall clinical outcomes in patients undergoing endovascular thrombectomy (EVT) for ICA occlusions.

Methods

Data from 1367 consecutive stroke cases treated with EVT from 2012-2019 were prospectively collected from a single center. Univariate and multivariate logistic regression were used to assess the relationship between IV-tPA administration and clinical outcome.

Results

153 patients were found to have carotid terminus and tandem ICAO who received EVT and presented within 4.5h of last seen well. 50% (n = 82) received IV tPA. There were no differences between the groups with respect to age, NIHSS, time to EVT and ASPECTS score. 53% had tandem ICA-MCA occlusions. Rate of recanalization (≥ TICI 2B) and sICH did not significantly differ between the two groups. Regression analysis demonstrated no effect of IV-tPA on modified Rankin Score (mRS) at 90 days and overall mortality. Factors significantly associated with reduced mortality included lower age, lower NIHSS, and better rate of recanalization.

Conclusions

There was no significant difference in clinical outcomes in those receiving BT vs. direct EVT for ICAO. For centers with optimal door-to-puncture times, bypassing IV-tPA may expedite recanalization times and potentially yield more favorable outcomes. Patients with higher NIHSS and tandem lesions may have better outcomes with BT.

Diagnosis and treatment of acute isolated proximal internal carotid artery occlusions: a narrative review

The clinical manifestations of proximal (extracranial) internal carotid artery occlusions (pICAOs) may range from asymptomatic to acute, large, and devastating ischemic strokes. The etiology and pathophysiology of the occlusion, intracranial collateral status and patient's premorbid status are among the factors determining the clinical presentation and outcome of pICAOs. Rapid and accurate diagnosis is crucial and may be assisted by the combination of carotid and transcranial duplex sonography, or a computed tomography/magnetic resonance angiography (CTA/MRA). It should be noted that with either imaging modalities, the discrimination of a pseudo-occlusion of the extracranial internal carotid artery (ICA) from a true pICAO may not be straightforward. In the absence of randomized data, the management of acute, symptomatic pICAOs remains individualized and relies largely on expert opinion. Administration of intravenous thrombolysis is reasonable and probably beneficial in the settings of acute ischemic stroke with early presentation. Unfortunately, rates of recanalization are rather low and acute interventional reperfusion therapies emerge as a potentially powerful therapeutic option for patients with persistent and severe symptoms. However, none of the pivotal clinical trials on mechanical thrombectomy for acute ischemic stroke randomized patients with isolated extracranial large vessel occlusions. On the contrary, several lines of evidence from non-randomized studies have shown that acute carotid endarterectomy, or endovascular thrombectomy/stenting of the ICA are feasible and safe, and pοtentially beneficial. The heterogeneity in the pathophysiology and clinical presentation of acute pICAOs renders patient selection for an acute interventional treatment a complicated decision-making process. The present narrative review will outline the pathophysiology, clinical presentation, diagnostic challenges, and possible treatment options for pICAOs.

Factors Distinguishing Proximal and Distal Internal Carotid Artery Occlusions in Patients with Acute Ischemic Stroke

Acute internal carotid artery (ICA) occlusions cause extensive brain ischemia. Accurate determination of the occlusion site facilitates rapid revascularization interventions and improves prognosis. However, proximal ICA occlusions, as determined with computed tomography (CT) angiography, often are located more distally. Therefore, we assessed clinical and imaging factors associated with the accurate determination of occlusion sites. In this observational study, we evaluated 102 patients who presented acute ischemic stroke symptoms and had a CT angiography within 6 h, showing proximal ICA occlusion. The participants were divided into two groups, depending on whether there was correspondence between digital subtraction angiography and CT angiography regarding the occlusion location. Proximal occlusions were, accordingly, categorized as “true” (correspondence) or “false” (no correspondence; distal). Demographic, clinical, and imaging features were analyzed. Multivariate regression analysis was performed to identify factors predicting the correspondence between actual ICA occlusion sites and those detected by CT angiography. The shape (Odds ratios, OR = 646.584; Confidence interval, CI = 21.703–19263.187; p < 0.001) and the length (OR = 0.696; CI = 0.535–0.904; p = 0.007) of the ICA occlusion and atrial fibrillation (OR = 0.024; CI = 0.002–0.340; p = 0.006) were significant factors. The cut-off length of ICA stump at 6.2 mm, the sensitivity was 71%, and the specificity was 70% (area under the ROC curve = 0.767).

A Dynamic Nomogram for 3-Month Prognosis for Acute Ischemic Stroke Patients After Endovascular Therapy: A Pooled Analysis in Southern China

Cerebral edema (CDE) is a common complication in patients with acute ischemic stroke (AIS) and can reduce the benefit of endovascular therapy (EVT). To determine whether certain risk factors are associated with a poor prognosis mediated by CDE after EVT. The 759 patients with anterior circulation stroke treated by EVT at three comprehensive stroke centers in China from January 2014 to October 2020 were analyzed. Patients underwent follow-up for 3 months after inclusion. The primary endpoint was a measure of a poor prognosis (modified Rankin Scale score ≥ 3) at 3 months assessed in all patients receiving EVT. Least absolute shrinkage and selection operator and multivariate logistic regression were used to select variables for the prognostic nomogram. Based on these variables, the nomogram was established and validated. In addition, structural equation modeling was used to explore the pathways linking CDE and a poor prognosis. Seven predictors were identified, namely, diabetes, age, baseline Alberta Stroke Program Early CT score, modified Thrombolysis in Cerebral Infarction score, early angiogenic CDE, National Institutes of Health Stroke Scale score, and collateral circulation. The nomogram consisting of these variables showed the best performance, with a large area under the curve in both the internal validation set (0.850; sensitivity, 0.737; specificity, 0.887) and external validation set (0.875; sensitivity, 0.752; specificity, 0.878). In addition, CDE (total path coefficient = 0.24, P < 0.001) served as a significant moderator. A nomogram for predicting a poor prognosis after EVT in AIS patients was established and validated with CDE as a moderator.

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.

European Stroke Organisation (ESO) guidelines on intravenous thrombolysis for acute ischaemic stroke

Intravenous thrombolysis is the only approved systemic reperfusion treatment for patients with acute ischaemic stroke. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions with regard to intravenous thrombolysis for acute ischaemic stroke. These guidelines were developed based on the ESO standard operating procedure and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote recommendations. Expert consensus statements were provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found high quality evidence to recommend intravenous thrombolysis with alteplase to improve functional outcome in patients with acute ischemic stroke within 4.5 h after symptom onset. We also found high quality evidence to recommend intravenous thrombolysis with alteplase in patients with acute ischaemic stroke on awakening from sleep, who were last seen well more than 4.5 h earlier, who have MRI DWI-FLAIR mismatch, and for whom mechanical thrombectomy is not planned. These guidelines provide further recommendations regarding patient subgroups, late time windows, imaging selection strategies, relative and absolute contraindications to alteplase, and tenecteplase. Intravenous thrombolysis remains a cornerstone of acute stroke management. Appropriate patient selection and timely treatment are crucial. Further randomized controlled clinical trials are needed to inform clinical decision-making with regard to tenecteplase and the use of intravenous thrombolysis before mechanical thrombectomy in patients with large vessel occlusion.

Chronic total occlusion and spontaneous recanalization of the internal carotid artery: Natural history and management strategy

OBJECTIVES

Spontaneous recanalization of a chronic total occlusion of the extra-cranial internal carotid artery is an under-reported clinical entity. This paper reviews the different etiologies of internal carotid artery occlusion, its natural course, as well as the significance and our recommendations for the management of spontaneous internal carotid artery recanalization.

METHODS

A review of literature on etiology, diagnosis, and treatment of internal carotid artery occlusion and recanalization was conducted. PubMed database was searched using the terms "internal carotid occlusion" and "recanalization". Articles were reviewed and studies involving the management of internal carotid artery occlusion and spontaneous recanalization were included. We subsequently developed a management algorithm for chronic total occlusion of the internal carotid artery and spontaneous recanalization of such lesions based on the available evidence.

RESULTS

Common etiologies of chronic total occlusion of the internal carotid artery include carotid atherosclerotic disease, cardioembolic, and carotid dissection. Progression of an asymptomatic to symptomatic occlusion is estimated at 2-8% annually. Well-compensated patients can be asymptomatic. In others, clinical symptoms range from ipsilateral or global hypoperfusion to embolic stroke in some cases of spontaneous recanalization. Spontaneous recanalization occurs in 2.3-10.3% of patients but rarely results in a cerebrovascular event.

CONCLUSIONS

Progression of an asymptomatic chronic total occlusion of the internal carotid artery to symptomatic is infrequent. The management algorithm of chronic total occlusion of the internal carotid artery and spontaneous recanalization of the internal carotid artery must be tailored to the patient based on symptoms, etiology of the lesion, imaging findings, surgical risk, and reliability for follow-up.

Management and prognosis of acute extracranial internal carotid artery occlusion

Acute occlusion of the internal carotid artery is the underlying etiology in 4 to 15% of all ischemic strokes. The clinical presentation varies considerably ranging from asymptomatic occlusion to severe ischemic strokes. Substantial differences in the acute management of acute symptomatic internal carotid artery occlusions (ICAO) exists between centers. Thusly, we comprised a narrative review of the natural course of acute ICAO and of available treatment options [i.v. thrombolysis, endovascular thrombectomy and stenting, bypass between the superficial temporal and the middle cerebral arteries (MCA) and carotid endarterectomy (CEA)]. We found that very few randomized treatment trials have been performed in patients acute symptomatic ICAO. Most evidence stems from case series and observational studies. Especially in older studies the intracranial vessel status has rarely been considered. After revision of these studies we concluded that the mainstay of the acute management of acute symptomatic ICAO is i.v. thrombolysis when applied within the label and in combination with mechanical thrombectomy in case of intracranial large vessel occlusion. In cases without intracranial large vessel occlusion mechanical thrombectomy of acute ICAO is associated with a risk of distal embolization. More research on prognostic parameters is needed to better characterize the risk of decompensation of collateral flow and to better define the time-window of intervention. When mechanical thrombectomy fails or is not available, surgical approaches are an alternative in selected patients.

Endovascular treatment and cognitive outcome after anterior circulation ischemic stroke

The impact of reperfusion therapies on cognition has been poorly explored and little knowledge exists. We explored the influence of endovascular treatment (EVT) on cognitive outcome in patients with anterior circulation ischemic stroke. Patients presenting with ischemic stroke due to anterior large vessel occlusion who underwent intravenous thrombolysis (IVT) alone or EVT plus IVT were recruited. Cognitive abilities were evaluated at 6 months from stroke through a neuropsychological test battery. A total of 88 patients with a mean age of 66.3 ± 12.9 years were included, of which 38 treated with IVT alone and 50 with IVT plus EVT. Compared to patients treated with IVT alone, patients who received EVT plus IVT performed significantly better at the neuropsychological tests exploring executive functions, attention, abstract reasoning, visuospatial ability, visual and verbal and memory. At multivariable regression analysis, the EVT was independently associated with the 6-month cognitive performance after the adjustment for age, sex, admission National Institutes of Health Stroke Scale score, systolic blood pressure, glucose level, Alberta Stroke Program Early CT score, side of stroke, site of occlusion, and Back Depression Inventory score [Stroop Test Word Reading: _adjβ = 13.99, 95% confidence interval (CI) 8.47–19.50, p < 0.001; Stroop Test Colour Naming: _adjβ = 6.63, 95% CI 2.46–10.81, p = 0.002; Trail Making Test-A: _adjβ = − 92.98, 95% CI − 153.76 to − 32.20, p = 0.003; Trail Making Test-B: _adjβ = − 181.12, 95% CI − 266.09 to − 96.15; p < 0.001; Digit Span Test Forward: _adjβ = 1.44, 95% CI 0.77–2.10, p < 0.001; Digit Span Test Backward: _adjβ = 1.10, 95% CI 0.42–1.77, p = 0.002; Coloured Progressive Matrices: _adjβ = 5.82, 95% CI 2.71–8.93, p < 0.001; Rey Complex Figure Test-Copy: _adjβ = 6.02, 95% CI 2.74–9.30, p < 0.001; Rey Complex Figure Test-Immediate recall: _adjβ = 6.00, 95% CI 2.34–9.66, p = 0.002; Rey Complex Figure Test-Delayed recall: _adjβ = 5.73, 95% CI 1.95–9.51, p = 0.003; Rey Auditory Verbal Learning Test-Immediate recall: _adjβ = 12.60, 95% CI 6.69–18.52, p < 0.001; Rey Auditory Verbal Learning Test-Delayed recall: _adjβ = 1.85, 95% CI 0.24–3.45, p = 0.025]. Patients treated with EVT plus IVT had better cognitive performance than patients treated with IVT alone at 6 months from anterior circulation ischemic stroke.

Early neurological deterioration following thrombolysis for minor stroke with isolated internal carotid artery occlusion

BACKGROUND AND PURPOSE

Better understanding the incidence, predictors and mechanisms of early neurological deterioration (END) following intravenous thrombolysis (IVT) for acute stroke with mild symptoms and isolated internal carotid artery occlusion (iICAo) may inform therapeutic decisions.

METHODS

From a multicenter retrospective database, we extracted all patients with both National Institutes of Health Stroke Scale (NIHSS) score <6 and iICAo (i.e. not involving the Willis circle) on admission imaging, intended for IVT alone. END was defined as ≥4 NIHSS points increase within 24 h. END and no-END patients were compared for (i) pre-treatment clinical and imaging variables and (ii) occurrence of intracranial occlusion, carotid recanalization and parenchymal hemorrhage on follow-up imaging.

RESULTS

Seventy-four patients were included, amongst whom 22 (30%) patients experienced END. Amongst pre-treatment variables, suprabulbar carotid occlusion was the only admission predictor of END following stepwise variable selection (odds ratio = 4.0, 95% confidence interval: 1.3-12.2; P = 0.015). On follow-up imaging, there was no instance of parenchymal hemorrhage, but an intracranial occlusion was now present in 76% vs. 0% of END and no-END patients, respectively (P < 0.001), and there was a trend toward higher carotid recanalization rate in END patients (29% vs. 9%, P = 0.07). As compared to no-END, END was strongly associated with a poor 3-month outcome.

CONCLUSIONS

Early neurological deterioration is a frequent and highly deleterious event after IVT for minor stroke with iICAo, and is of thromboembolic origin in three out of four patients. The strong association with iICAo site-largely a function of underlying stroke etiology-may point to a different response of the thrombus to IVT. These findings suggest END may be preventable in this setting.

Reperfusion strategies in stroke due to isolated cervical internal carotid artery occlusion: systematic review and treatment comparison

Introduction

Despite intravenous thrombolysis (IVT) and endovascular treatment (EVT) have been demonstrated effective in acute ischemic stroke (AIS) due to large vessel occlusions, there are still no conclusive data to guide treatment in stroke due to cervical internal carotid artery (ICA) occlusion. We systematically reviewed available literature to compare IVT, EVT, and bridging (IVT + EVT) and define optimal treatment.

Methods

Systematic review followed predefined protocol (Open-Science-Framework osf.io/bfykj). MEDLINE, EMBASE, and Cochrane CENTRAL were searched. Results were restricted to studies in English, with sample size ≥ 10 and follow-up ≥30 days. Primary outcomes were favorable outcome (mRS ≤ 2), mortality, and symptomatic intracerebral hemorrhage(sICH), defined according to study original report. Newcastle-Ottawa scale was used for bias assessment.

Results

Seven records of 930 screened were included in meta-analysis. Quality of studies was low-to-fair in 5, good in 2. IVT (n = 450) did not differ for favorable outcome and mortality compared to EVT (n = 150), though having lower rate of sICH (OR = 0.4, 95% CI 0.2–0.8). Compared to IVT, bridging (IVT + EVT) was associated with higher rate of favorable outcome (OR = 2.2, 95% CI 1.3–3.7). Compared to EVT, bridging (IVT + EVT) provided higher rate of favorable outcome (OR = 1.9, 95% CI 1.1–3.4), with a marginally increased risk of sICH (OR = 2.1, 95% CI 1–4.4) but similar mortality rates.

Conclusions

Our systematic review highlights that, in acute ischemic stroke associated with isolated cervical ICA occlusion, bridging (IVT + EVT) might lead to higher rate of functional independence at follow-up, without increasing mortality. The low quality of available studies prevents from drawing firm conclusions, and randomized-controlled clinical trials are critically needed to define optimal treatment in this AIS subgroup.

Electronic supplementary material

The online version of this article (10.1007/s10072-020-04735-5) contains supplementary material, which is available to authorized users.

Symptomatic isolated internal carotid artery occlusion with initial medical management: a monocentric cohort

BACKGROUND

Symptomatic isolated carotid artery occlusions (ICAO) can lead to disability, recurrent stroke, and mortality, but natural history and best therapeutic management remain poorly known. The objective of this study was to describe our cohort of ICAO patients with an initial medical management.

METHODS

We conducted a retrospective study including consecutive patients admitted to our Comprehensive Stroke Center for ICAO within 24 h after stroke onset between January 2016 and September 2018. Patients with immediate endovascular therapy (EVT) were excluded. Medical treatment was based on anticoagulation (delayed by 24 h if intravenous thrombolysis was performed). 'Rescue' EVT was considered if first-week neurological deterioration (FWND) occurred.

RESULTS

Fifty-six patients were included, with a median National Institutes of Health Stroke Scale (NIHSS) of 3. Eleven patients (20%) had FWND during the first week, four benefited from rescue EVT. A mismatch volume > 40 cc on initial perfusion imaging and FLAIR vascular hyperintensities were associated with FWND (p = 0.007 and p = 0.009, respectively). Thirty-eight patients (69%) had a good outcome (modified Rankin Scale mRS 0-2) at 3 months, 36 (69%) had an excellent outcome (mRS 0-1). Seventeen patients (38%) had carotid patency on 3-month control imaging. Recurrences occurred in six (13%) of the survivors (mean follow-up: 13.6 months).

CONCLUSION

Our results suggest that the prognosis of patients with acute ICAO was favorable with a medical strategy, albeit a substantial rate of FWND and recurrence. FWND was well predicted by a core-perfusion mismatch volume > 40 cc. Randomized controlled trials are necessary to assess the benefit of EVT in ICAO.

Effect of Recanalization on Cerebral Edema in Ischemic Stroke Treated With Thrombolysis and/or Endovascular Therapy

Background and Purpose- A large infarct and expanding cerebral edema (CED) due to a middle cerebral artery occlusion confers a 70% mortality unless treated surgically. Reperfusion may cause blood-brain barrier disruption and a risk for cerebral edema and secondary parenchymal hemorrhage (PH). We aimed to investigate the effect of recanalization on development of early CED and PH after recanalization therapy. Methods- From the SITS-International Stroke Treatment Registry, we selected patients with signs of artery occlusion at baseline (either Hyperdense Artery Sign or computed tomography/magnetic resonance imaging angiographic occlusion). We defined recanalization as the disappearance of radiological signs of occlusion at 22 to 36 hours. Primary outcome was moderate to severe CED and secondary outcome was PH on 22- to 36-hour imaging scans. We used logistic regression with adjustment for baseline variables and PH. Results- Twenty two thousand one hundred eighty-four patients fulfilled the inclusion criteria (n=18 318 received intravenous thrombolysis, n=3071 received intravenous thrombolysis+thrombectomy, n=795 received thrombectomy). Recanalization occurred in 64.1%. Median age was 71 versus 71 years and National Institutes of Health Stroke Scale score 15 versus 16 in the recanalized versus nonrecanalized patients respectively. Recanalized patients had a lower risk for CED (13.0% versus 23.6%), adjusted odds ratio (aOR), 0.52 (95% CI, 0.46-0.59), and a higher risk for PH (8.9% versus 6.5%), adjusted odds ratio, 1.37 (95% CI, 1.22-1.55), than nonrecanalized patients. Conclusions- In patients with acute ischemic stroke, recanalization was associated with a lower risk for early CED even after adjustment for higher rate for PH in recanalized patients.

Acute ischaemic stroke interventions: large vessel occlusion and beyond

Care for acute ischaemic stroke is one of the most rapidly evolving fields due to the robust outcomes achieved by mechanical thrombectomy. Large vessel occlusion (LVO) accounts for up to 38% of acute ischaemic stroke and comes with devastating outcomes for patients, families and society in the pre-intervention era. A paradigm shift and a breakthrough brought mechanical thrombectomy back into the spotlight for acute ischaemic stroke; this was because five randomised controlled trials from several countries concluded that mechanical thrombectomy for acute stroke offered overwhelming benefits. This review article will present a comprehensive overview of LVO management, techniques and devices used, and the future of stroke therapy. In addition, we review our institution experience of mechanical thrombectomy for posterior and distal circulation occlusion.

Surgery of acute occlusion of the extracranial internal carotid artery - a meta-analysis

Acute occlusion of the extracranial internal carotid artery (eICA) is associated with poor prognosis. Surgical desobliteration has not received adequate attention in recent years. We therefore conducted a literature review and meta-analysis of surgical studies published after 2000 that treated eICA occlusion surgically in an emergency setting. The search identified 10 relevant articles that included a total of 175 patients. The outcomes analysed included rates of recanalization (93 %), early neurological improvement (66 %), modified Rankin Scale 0-2 (62 %), mortality (5 %), early reocclusion (4 %), in-hospital stroke (4 %) and symptomatic intracerebral haemorrhage (4 %). In conclusion, acute surgical desobliteration of eICA occlusion leads to high rates of recanalization and a majority of patients experience early neurological improvement and achieve favourable outcome. Rates of mortality, early reocclusion, in-hospital stroke and sICH are acceptable in the view of unfavourable natural history.

Imaging in neurointerventional stroke treatment: review of the recent trials and what your neurointerventionalist wants to know from emergency radiologists

Stroke is one of the leading causes of death and disability worldwide. Standard treatment for stroke is intravenous (IV) injection of tissue plasminogen activator (t-PA) rapidly after symptom onset. However, there are limitations of IV t-PA treatment, such as a short time window for administration and risk for hemorrhage. Recent trials have demonstrated the benefit of endovascular treatment when added to standard treatment to improve outcomes for patients. Advanced imaging was utilized in some trials to identify patients with proximal intracranial occlusion to target for endovascular reperfusion therapy, and to exclude patients with large infarct cores or poor collateral circulation who would not be expected to benefit from intervention. This article summarizes the use of imaging in recent stroke trials in details, provides a stroke imaging protocol, and provides tips which radiologists should know to help their neurointerventionalists.

The role of plasminogen activators in stroke treatment: fibrinolysis and beyond

Although recent technical advances in thrombectomy have revolutionised acute stroke treatment, prevalence of disability and death related to stroke remain high. Therefore, plasminogen activators-eukaryotic, bacterial, or engineered forms that can promote fibrinolysis by converting plasminogen into active plasmin and facilitate clot breakdown-are still commonly used in the acute treatment of ischaemic stroke. Hence, plasminogen activators have become a crucial area for clinical investigation for their ability to recanalise occluded arteries in ischaemic stroke and to accelerate haematoma clearance in haemorrhagic stroke. However, inconsistent results, insufficient evidence of efficacy, or reports of side-effects in trial settings might reduce the use of plasminogen activators in clinical practice. Additionally, the mechanism of action for plasminogen activators could extend beyond the vessel lumen and involve plasminogen-independent processes, which would suggest that plasminogen activators have also non-fibrinolytic roles. Understanding the complex mechanisms of action of plasminogen activators can guide future directions for therapeutic interventions in patients with stroke.

Endovascular Reperfusion for Acute Isolated Cervical Carotid Occlusions: The Concept of "Hemodynamic Thrombectomy"

Background/Aims

Endovascular treatment improves the outcomes of patients presenting with acute large vessel occlusions. Isolated proximal carotid occlusions presenting with hemodynamic ischemic stroke may probably also benefit from endovascular treatment. We aimed to assess the clinical and radiological data findings on patients who underwent endovascular treatment for acute ischemic stroke related to an isolated cervical carotid artery occlusion.

Methods

Of a consecutive series of 223 patients who were admitted with acute ische-mic stroke and were treated by thrombectomy, we included 9 patients with isolated cervical internal carotid occlusions.

Results

The mean baseline National Institutes of Health Stroke Scale (NIHSS) score was 11.8. Complete carotid recanalization was achieved in 5 of the 9 patients (55.5%). In 2 patients, vertebral angioplasty was performed to improve the collateral flow. All patients had a modified Thrombolysis in Cerebral Infarction (mTICI) score of 3 at the end of the procedures. A good neurological outcome, defined as a modified Rankin Scale score ≤2 at the 3-month follow-up, was observed in 6 patients (66.7%). No symptomatic intracranial hemorrhages or deaths occurred during the 3 months of follow-up.

Conclusions

The endovascular recanalization of isolated cervical carotid occlusions presenting with acute ischemic stroke symptoms is feasible. Because isolated cervical carotid occlusions are associated with hemodynamic ischemic symptoms, if carotid recanalization cannot be achieved, stenting other cervical arteries' stenoses, with a focus on intracranial flow improvement, appears to be a reasonable strategy. Large controlled studies are necessary to assess the safety and efficacy of recanalization of acute isolated cervical carotid occlusions.

Impact of Bradykinin Generation During Thrombolysis in Ischemic Stroke

Ischemic stroke is one of the leading causes of death and disability worldwide. Current medical management in the acute phase is based on the activation of the fibrinolytic cascade by intravenous injection of a plasminogen activator (such as tissue-type plasminogen activator, tPA) that promotes restauration of the cerebral blood flow and improves stroke outcome. Unfortunately, the use of tPA is associated with deleterious effects such as hemorrhagic transformation, symptomatic brain edema, and angioedema, which limit the efficacy of this therapeutic strategy. Preclinical and clinical evidence suggests that intravenous thrombolysis generates large amounts of bradykinin, a peptide with potent pro-inflammatory, and pro-edematous effects. This tPA-triggered generation of bradykinin could participate in the deleterious effects of thrombolysis and is a potential target to improve neurological outcome in tPA-treated patients. The present review aims at summarizing current evidence linking thrombolysis, bradykinin generation, and neurovascular damage.

Intravenous thrombolysis for acute ischemic stroke: a bridge between two centuries

INTRODUCTION

Intravenous tissue-plasminogen activator (tPA) remains the only approved systemic reperfusion therapy suitable for most patients presenting timely with acute ischemic stroke. Accumulating real-word experience for over 20 years regarding tPA safety and effectiveness led to re-appraisal of original contraindications for intravenous thrombolysis (IVT). Areas covered: This narrative review focuses on fast yet appropriate selection of patients for safe administration of tPA per recently expanded indications. Novel strategies for rapid patient assessment will be discussed. The potential for mobile stroke units (MSU) that shorten onset-to-needle time and increase tPA treatment rates is addressed. The use of IVT in the era of non-vitamin K antagonist oral anticoagulants (NOACs) is highlighted. The continuing role of IVT in large vessel occlusion (LVO) patients eligible for mechanical thrombectomy (MT) is discussed with regards to 'drip and ship' vs. 'mothership' treatment paradigms. Promising studies of penumbral imaging to extend IVT beyond the 4.5-hour window and in wake-up strokes are summarized. Expert commentary: This review provides an update on the role of IVT in specific conditions originally considered tPA contraindications. Novel practice challenges including NOAC's, MSU proliferation and bridging therapy (IVT&MT) for LVO patients, and the potential extension of IVT time-window using penumbral imaging are emerging as safe and potentially effective IVT applications.

An Overview of Meta-Analyses of Endovascular Bridging Therapies for Acute Ischemic Stroke

Background

Acute Ischemic Stroke (AIS) is a common cause of death worldwide and the leading cause of long-term severe disability. Endovascular bridging therapies (EBT), including endovascular thrombectomy (ET) and intra-arterial thrombolytic (IAT), have been recommended to realize a favorable functional outcome for AIS patients.

Methods

An overview of meta-analyses of primary randomized controlled trial (RCT) studies was performed evaluating EBT for AIS patients compared with usual care.

Results

Ten meta-analyses were included in this overview. ET was associated with a higher incidence of achieving functional outcome improvement, defined as a modified Rankin scale of 0 to 1 (mRS, p = 0.003), 0 to 2 (p < 0.00001), and 0 to 3 (p = 0.005). The risk of symptomatic intracranial hemorrhage (sICH) rate and all-cause mortality were similar between the two groups. Moreover, IAT treatment was also related to significantly improved outcomes in terms of the mRS score (p < 0.05), but no significant difference in rates of sICH and mortality within 90 days.

Conclusions

In conclusion, our analysis supports that EBT, regardless of format (e.g., ET or IAT), is superior to the best medical therapy alone (e.g., IVT) in terms of mRS score in patients with AIS. In addition, the safety of EBT is similar to IVT.

Reperfusion therapy in acute ischemic stroke: dawn of a new era?

Following the success of recent endovascular trials, endovascular therapy has emerged as an exciting addition to the arsenal of clinical management of patients with acute ischemic stroke (AIS). In this paper, we present an extensive overview of intravenous and endovascular reperfusion strategies, recent advances in AIS neurointervention, limitations of various treatment paradigms, and provide insights on imaging-guided reperfusion therapies. A roadmap for imaging guided reperfusion treatment workflow in AIS is also proposed. Both systemic thrombolysis and endovascular treatment have been incorporated into the standard of care in stroke therapy. Further research on advanced imaging-based approaches to select appropriate patients, may widen the time-window for patient selection and would contribute immensely to early thrombolytic strategies, better recanalization rates, and improved clinical outcomes.

Usefulness of contralateral carotid angiography in revascularization therapy of acute internal carotid artery occlusion

OBJECTIVE The vascular lumen of an acutely occluded internal carotid artery (ICA) generally contains numerous thrombi. Therefore, carotid angiography on the affected side during revascularization therapy of acute ICA occlusion has a potential risk of causing distal embolization. In this study the authors propose the use of contralateral carotid angiography. METHODS Six patients with acute ICA occlusion underwent revascularization therapy using a stent retriever or Penumbra system. Revascularization therapy was performed with placement of a 9-Fr balloon-guiding catheter (BGC) in the affected ICA and a 4-Fr diagnostic catheter in the contralateral ICA. During the procedure, the 9-Fr BGC was kept inflated, and all control angiography was performed from the 4-Fr diagnostic catheter. After thrombectomy, contralateral carotid angiography combined with manual aspiration from the 9-Fr BGC was performed to assess the presence or absence of residual thrombi in the affected ICA. The 9-Fr BGC was deflated only after the complete absence of residual thrombi in the affected ICA was confirmed. RESULTS The time required for introducing the 4-Fr diagnostic catheter into the contralateral ICA was within a few minutes in all patients. Residual thrombi in the affected ICA were found in 3 of 6 patients. The residual thrombi in these 3 patients were completely removed; thus, distal embolization was prevented. CONCLUSIONS Contralateral carotid angiography is useful for avoiding distal embolization during revascularization therapy of acute ICA occlusion. Further studies involving a larger number of patients are warranted to verify the clinical efficacy of this contralateral carotid angiography.

Internal Carotid Artery Occlusion: Pathophysiology, Diagnosis, and Management

PURPOSE OF REVIEW

Acute internal carotid artery occlusion (ICAO) is associated with large infarcts and poor clinical outcomes and contributes to morbidity and mortality worldwide. In this review, we discuss various etiologies and pathophysiology of clinical presentations of ICAO, different radiographic patterns, and management of patients with ICAO.

RECENT FINDINGS

Recanalization rates remain suboptimal with systemic thrombolysis amongst patients with acute ICAO. Recent success of endovascular therapy for vessel occlusion in anterior circulation has expanded the horizons; however, few patients with cervical dissections and ICAO were included in these landmark trials. Acute ICAO responds poorly to intravenous thrombolysis and portends worse clinical outcomes. Extracranial and intracranial ICAOs have varied clinical course and imaging patterns, with discrete cervical ICAO usually associated with better clinical outcomes while tandem occlusions predispose poor outcomes. Diagnostic catheter-based angiogram is often required since appearances of ICAO using non-invasive neuroimaging modalities are often deceiving. Repeated vascular imaging in acute to subacute phase to determine recanalization of ICAO is critical for secondary prevention. Recent success of endovascular procedures will continue to expand the horizons to improve the management of ICAO.

Anticoagulation Bridge Therapy in Patients with Atrial Fibrillation: Recent Updates Providing a Rebalance of Risk and Benefit

In 2011 we reviewed clinical updates and controversies surrounding anticoagulation bridge therapy in patients with atrial fibrillation (AF). Since then, options for oral anticoagulation have expanded with the addition of four direct oral anticoagulant (DOAC) agents available in the United States. Nonetheless, vitamin K antagonist (VKA) therapy continues to be the treatment of choice for patients who are poor candidates for a DOAC and for whom bridge therapy remains a therapeutic dilemma. This literature review identifies evidence and guideline and consensus statements from the last 5 years to provide updated recommendations and insight into bridge therapy for patients using a VKA for AF. Since our last review, at least four major international guidelines have been updated plus a new consensus document addressing bridge therapy was released. Prospective trials and one randomized controlled trial have provided guidance for perioperative bridge therapy. The clinical trial data showed that bridging with heparin is associated with a significant bleeding risk compared with not bridging; furthermore, data suggested that actual perioperative thromboembolic risk may be lower than previously estimated. Notably, patients at high risk for stroke have not been adequately represented. These findings highlight the importance of assessing thrombosis and bleeding risk before making bridging decisions. Thrombosis and bleeding risk tools have emerged to facilitate this assessment and have been incorporated into guideline recommendations. Results from ongoing trials are expected to provide more guidance on safe and effective perioperative management approaches for patients at high risk for stroke.

Acute Ischemic Stroke Intervention

Acute ischemic stroke (AIS) is the leading cause of disability worldwide and among the leading causes of mortality. Although intravenous tissue plasminogen activator (IV-rtPA) was approved nearly 2 decades ago for treatment of AIS, only a minority of patients receive it due to a narrow time window for administration and several contraindications to its use. Endovascular approaches to recanalization in AIS developed in the 1980s, and recently, 5 major randomized trials showed an overwhelming superior benefit of combining endovascular mechanical thrombectomy with IV-rtPA over IV-rtPA alone. In this paper, we discuss the evolution of catheter-based treatment from first-generation thrombectomy devices to the game-changing stent retrievers, results from recent trials, and the evolving stroke systems of care to provide timely access to acute stroke intervention to patients in the United States.

Distinctive patterns on CT angiography characterize acute internal carotid artery occlusion subtypes

Noninvasive computed tomography angiography (CTA) is widely used in acute ischemic stroke, even for diagnosing various internal carotid artery (ICA) occlusion sites, which often need cerebral digital subtraction angiography (DSA) confirmation. We evaluated whether clinical outcomes vary depending on the DSA-based occlusion sites and explored correlating features on baseline CTA that predict DSA-based occlusion site.We analyzed consecutive patients with acute ICA occlusion who underwent DSA and CTA. Occlusion site was classified into cervical, cavernous, petrous, and carotid terminus segments by DSA confirmation. Clinical and radiological features associated with poor outcome at 3 months (3-6 of modified Rankin scale) were analyzed. Baseline CTA findings were categorized according to carotid occlusive shape (stump, spearhead, and streak), presence of cervical calcification, Willisian occlusive patterns (T-type, L-type, and I-type), and status of leptomeningeal collaterals (LMC).We identified 49 patients with occlusions in the cervical (n = 17), cavernous (n = 22), and carotid terminus (n = 10) portions: initial NIH Stroke Scale (11.4 ± 4.2 vs 16.1 ± 3.7 vs 18.2 ± 5.1; P < 0.001), stroke volume (27.9 ± 29.6 vs 127.4 ± 112.6 vs 260.3 ± 151.8 mL; P < 0.001), and poor outcome (23.5 vs 77.3 vs 90.0%; P < 0.001). Cervical portion occlusion was characterized as rounded stump (82.4%) with calcification (52.9%) and fair LMC (94.1%); cavernous as spearhead occlusion (68.2%) with fair LMC (86.3%) and no calcification (95.5%); and terminus as streak-like occlusive pattern (60.0%) with poor LMC (60.0%), and no calcification (100%) on CTA.Our study indicates that acute ICA occlusion can be subtyped into cervical, cavernous, and terminus. Distinctive findings on initial CTA can help differentiate ICA-occlusion subtypes with specific characteristics.

Symbiotic relationship of IV-tPA and mechanical thrombectomy in a case of acute tandem ICA-MCA occlusion

INTRO

In light of the recent successful mechanical thrombectomy trials, the need for IV-tPA prior is under investigation. Few cases demonstrate angiographically the role of both mechanical and chemical strategies at achieving reperfusion.

CASE REPORT

A 63year-old male presented with an NIHSS 20. CTA demonstrated an acute occlusion of the left cervical and intracranial ICA and MCA. IV-tPA was administered, followed by immediate reperfusion of the cervical ICA with carotid stenting and mechanical thrombectomy. Within the next 10min, the entire intracranial clot burden dissolved under angiographic control. TICI 3 reperfusion was achieved without any further intervention. Post-procedure, the patient recovered fully to an NIHSS of 0.

CONCLUSION

This case underscores the importance of IV-tPA administration in conjunction to mechanical thrombectomy. The interventionalist should take advantage of the symbiotic effect of the IV-tPA administration, which remains the standard of care so far.

Carotid artery stenting versus no stenting assisting thrombectomy for acute ischaemic stroke: protocol for a systematic review of randomised clinical trials with meta-analyses and trial sequential analyses

BACKGROUND

In patients with intracranial large vessel arterial occlusion, ipsilateral extracranial carotid artery occlusions or near-occlusions pose a significant hurdle in endovascular management of acute ischaemic stroke. Stenting of the carotid lesion may be beneficial in this situation to provide a stable access for introducing catheters through the carotid lesion into the intracranial vasculature and the target occlusion. Furthermore, carotid stenting may ensure ample blood flow for wash-out of clot material and reperfusion of the ischaemic penumbral tissue. However, antiplatelet therapy administered to prevent stent thrombosis and sudden increase in blood flow after reopening of the carotid lesion may increase the risk for intracranial haemorrhagic complications. This review aims to assess the benefits and harms of carotid stenting vs. no stenting assisting thrombectomy for acute ischaemic stroke.

METHODS

International and regional electronic databases will be searched to identify eligible randomised clinical trials. To identify further published, unpublished, or on-going and planned trials searches of Google Scholar, Worldwide Food and Drug Administrations, Worldwide Medicines Agencies, company homepages, reference lists, conference proceedings, and the Science Citation Index cited reference search index will be conducted. Manufacturers of relevant interventional equipment, authors, colleagues, and researchers active in the field will be contacted. No language restrictions will be applied to these searches. Randomised clinical trials will be included for assessing benefits and harms and quasi-randomised studies, and observational studies will be included for assessing harms of the intervention. Meta-analyses will be performed according to the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions, and Trial Sequential Analyses will be conducted to control the risk of random errors and prevent premature statements of superiority of the experimental or control intervention or premature statement of futility. The quality of the evidence will be evaluated with the Grading of Recommendations Assessment, Development, and Evaluation.

DISCUSSION

This systematic review of carotid stenting in endovascular management of acute ischaemic stroke in patients with concomitant extracranial carotid lesions and intracranial embolism will assess benefits and harms of this intervention and assesses whether carotid stenting should be encouraged or avoided in acute ischaemic stroke and identify targets for further research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016033346.

Acute Carotid Stent Thrombosis

Acute carotid stent thrombosis (ACST) is a rare complication that can lead to dramatic and catastrophic consequences. A rapid diagnosis and prompt recanalization of the internal carotid artery are needed to minimize the ischemic insult and the reperfusion injury. We reviewed the current literature on this devastating complication of CAS with the intention of investigating the potential causative factors and to define the appropriate management. According to our study discontinuation of antiplatelet therapy, resistance to antiplatelet agents and inherent or acquired thrombotic disorders are the main causes of thrombosis. Technical intraprocedural parameters such as dissection, atheroma prolapse, kinking of the distal part of internal carotid artery and embolic protection device occlusion can also result in early carotid stent thrombosis. Rapid reperfusion ensures an improved neurological outcome and a better prognosis in the short and long term. Thrombolysis, mechanical thrombectomy or thromboaspiration in combination with drug or thrombolytic therapy, surgical therapy and re-angioplasty are treatment options that have been used with encouraging results. In conclusion, optimal perioperative antiplatelet treatment as well as technical considerations regarding the carotid artery stenting plays a determinant role.

Treatment Strategies for Acute Ischemic Stroke Caused by Carotid Artery Occlusion

Background: Acute ischemic stroke caused by internal carotid artery (ICA) occlusion usually has a poor prognosis, especially the T occlusion cases without functional collaterals. The efficacy of intravenous (IV) or intra-arterial (IA) thrombolysis with recombinant tissue plasminogen activator (rt-PA) remains ambiguous in these patients. Eendovascular recanalization of the occluded carotid has been attempted in recent years as a potential strategy. However, the different etiologies of ICA occlusion pose a significant challenge to neurointerventionists. Recently, several endovascular evolvements have been reported in treating carotid occlusion-related stroke. This review summarizes the current status of treatment for acute ICA occlusion.

Intravenous Thrombolysis for Acute Ischemic Stroke due to Cervical Internal Carotid Artery Occlusion

BACKGROUND

Internal carotid artery (ICA) occlusions are poorly responsive to intravenous thrombolysis with tissue plasminogen activator (IV-tPA) in acute ischemic stroke (AIS). Most study populations have combined intracranial and extracranial ICA occlusions for analysis; few have studied purely cervical ICA occlusions. We evaluated AIS patients with acute cervical ICA occlusion treated with IV-tPA to identify predictors of outcomes.

METHODS

We studied 550 consecutive patients with AIS who received IV-tPA and identified 100 with pure acute cervical ICA occlusion. We evaluated the associations of vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score, and leptomeningeal collateral vessel status via 3 different grading systems, with functional recovery at 90 days, mortality, recanalization of the primary occlusion, and symptomatic intracranial hemorrhage (SICH). Modified Rankin Scale score 0-1 was defined as an excellent outcome.

RESULTS

The 100 patients had mean age of 67.8 (range 32-96) and median NIHSS score of 19 (range 4-33). Excellent outcomes were observed in 27% of the patients, SICH in 8%, and mortality in 21%. Up to 54% of the patients achieved recanalization at 24 hours. On ordinal regression, good collaterals showed a significant shift in favorable outcomes by Maas, Tan, or ASPECTS collateral grading systems. On multivariate analysis, good collaterals also showed reduced mortality (OR .721, 95% CI .588-.888, P = .002) and a trend to less SICH (OR .81, 95% CI .65-1.007, P = .058). Interestingly, faster treatment was also associated with favorable functional recovery (OR 1.028 per minute, 95% CI 1.010-1.047, P = .001).

CONCLUSIONS

Improved outcomes are seen in patients with early acute cervical ICA occlusion and better collateral circulation. This could be a valuable biomarker for decision making.

Evaluation of Gene Therapy as an Intervention Strategy to Treat Brain Injury from Stroke

Stroke is a leading cause of death and disability, with a lack of treatments available to prevent cell death, regenerate damaged cells and pathways, or promote neurogenesis. The extended period of hours to weeks over which tissue damage continues to occur makes this disorder a candidate for gene therapy. This review highlights the development of gene therapy in the area of stroke, with the evolution of viral administration, in experimental stroke models, from pre-injury to clinically relevant timeframes of hours to days post-stroke. The putative therapeutic proteins being examined include anti-apoptotic, pro-survival, anti-inflammatory, and guidance proteins, targeting multiple pathways within the complex pathology, with promising results. The balance of findings from animal models suggests that gene therapy provides a viable translational platform for treatment of ischemic brain injury arising from stroke.

Mechanical thrombectomy with the ERIC retrieval device: initial experience

Objective

To report our experience with the Embolus Retriever with Interlinked Cage (ERIC) stentriever for use in mechanical endovascular thrombectomy (MET).

Methods

Thirty-four consecutive patients with acute stroke (21 men and 13 women; median age 66 years) determined appropriate for MET were treated with ERIC and prospectively included over a 6-month period at three different centers. The ERIC device differs from typical stentrievers in that it is designed with a series of interlinked adjustable nitinol cages that allow for fast thrombus capture, integration, and withdrawal. The evaluated endpoints were successful revascularization (Thrombolysis in Cerebral Infarction (TICI) 2b–3) and good clinical outcomes at 3 months (modified Rankin Scale (mRS) 0–2).

Results

Locations of the occlusions included the middle cerebral artery (13 patients), terminal carotid artery (11 patients), basilar artery (1 patient), and tandem occlusions (9 patients). IV thrombolysis was performed in 20/34 (58.8%) patients. Median times from symptom onset to recanalization and from puncture to recanalization were 325.5 min (180–557) and 78.5 min (14–183), respectively. Used as the first-line device, ERIC achieved a successful recanalization in 20/24 (83.3%) patients. Successful recanalization was associated with lower National Institutes of Health Stroke Scale scores at 24 h (8±6.5 vs 21.5±2.1; p=0.008) and lower mRS at 3 months (2.7±2.1 vs 5.3±1.1; p=0.04). Three procedural complications and four asymptomatic hemorrhages were recorded. Good clinical outcomes at 3 months were seen in 15/31 (48.4%) patients.

Conclusions

The ERIC device is an innovative stentriever allowing fast, effective, and safe MET.

Solitaire™ with the Intention for Thrombectomy as Primary Endovascular Treatment for Acute Ischemic Stroke (SWIFT PRIME) trial: protocol for a randomized, controlled, multicenter study comparing the Solitaire revascularization device with IV tPA with IV tPA alone in acute ischemic stroke

Rationale

Early reperfusion in patients experiencing acute ischemic stroke is critical, especially for patients with large vessel occlusion who have poor prognosis without revascularization. Solitaire™ stent retriever devices have been shown to immediately restore vascular perfusion safely, rapidly, and effectively in acute ischemic stroke patients with large vessel occlusions.

Aim

The aim of the study was to demonstrate that, among patients with large vessel, anterior circulation occlusion who have received intravenous tissue plasminogen activator, treatment with Solitaire revascularization devices reduces degree of disability 3 months post stroke.

Design

The study is a global multicenter, two-arm, prospective, randomized, open, blinded end-point trial comparing functional outcomes in acute ischemic stroke patients who are treated with either intravenous tissue plasminogen activator alone or intravenous tissue plasminogen activator in combination with the Solitaire device. Up to 833 patients will be enrolled.

Procedures

Patients who have received intravenous tissue plasminogen activator are randomized to either continue with intravenous tissue plasminogen activator alone or additionally proceed to neurothrombectomy using the Solitaire device within six-hours of symptom onset.

Study Outcomes

The primary end-point is 90-day global disability, assessed with the modified Rankin Scale (mRS). Secondary outcomes include mortality at 90 days, functional independence (mRS ≤ 2) at 90 days, change in National Institutes of Health Stroke Scale at 27 h, reperfusion at 27 h, and thrombolysis in cerebral infarction 2b/3 flow at the end of the procedure.

Analysis

Statistical analysis will be conducted using simultaneous success criteria on the overall distribution of modified Rankin Scale (Rankin shift) and proportions of subjects achieving functional independence (mRS 0–2).

Successful recanalization for internal carotid artery occlusion with persistent primitive trigeminal artery manifesting only as ischemia of the posterior circulation

Background

Internal carotid artery (ICA) occlusion mainly manifests as ischemia of the anterior circulation. There are very few reports of ICA occlusion manifesting as only ischemia of the posterior circulation related to a fetal type posterior communicating artery or other arteries.

Case presentation

The authors experienced a case of ICA occlusion with persistent primitive trigeminal artery (PPTA) manifesting only as ischemia of the posterior circulation. In this case, the initial NIHSS score was high (35/42 points). Additionally, cross flow of the anterior communicating artery, ICA occlusion and basilar artery (BA) occlusion were represented on the initial head MRA. Therefore, our first impression was a presumptive diagnosis of BA occlusion. Prior head MRI/MRA performed for screening purposes, had incidentally demonstrated a right PPTA. Based on this understanding, we were able to determine the exact angioarchitectural mechanism of the ICA occlusion. Because of the presence of the PPTA, successful recanalization was accomplished expeditiously.

Conclusion

Although the presence of PPTA is rare and ICA occlusion patients with PPTA is even more unusual, if ICA occlusion and BA occlusion appear simultaneously on MRA, the presence of PPTA should be considered.

Carotid stent-assisted thrombectomy in acute ischemic stroke

Acute carotid occlusion or near-occlusion with concomitant intracranial embolism cause severe acute ischemic strokes in patients. These concomitant occlusions have suggested poor response to intravenous thrombolysis and complicate endovascular treatment. Nevertheless, endovascular stent-assisted thrombectomy may improve outcome in patients but the treatment is not without concerns. Required antiplatelet therapy to prevent stent thrombosis may increase the rate of intracranial hemorrhage, especially after recent thrombolysis. Furthermore, technical difficulties in access of the intracranial vasculature may cause adverse events, even in the hands of experienced interventionalists. These concerns currently defy the treatment in being recommended for general use and only on a compassionate basis. However, recent patient series have suggested reasonable safety and efficacy for carotid stent-assisted thrombectomy.

Emergent cervical surgical embolectomy for extracranial internal carotid artery occlusion

BACKGROUND

Acute extracranial internal carotid artery (ICA) occlusion by a huge cardiogenic embolus is rare, but can be catastrophic.

METHODS

Seven patients with acute ischemic stroke due to embolic occlusion of extracranial ICA who underwent emergent cervical surgical embolectomy were retrospectively reviewed. Diagnosis was made in six patients with magnetic resonance imaging (MRI) with optional digital subtraction angiography (DSA), while computed tomography (CT) and DSA were used in one patient with an implanted pacemaker. Clinical outcomes, including recanalization rate, recanalization time, complications, modified Rankin scale (mRS) at 3 months, and National Institute of Health Stroke Scale (NIHSS) score improvement at 1 month were evaluated.

RESULTS

Complete recanalization was obtained in seven patients (100 %). Median recanalization time from symptom onset and from start of surgery was 402 and 40 min, respectively. All seven patients showed severe left ventricular hypertrophy (LVH) according to an increased cardiothoracic ratio (CTR) ≥50 %. Complications included recurrence of cardioembolic stroke with the right middle cerebral artery occlusion, minimal expansion of infarction, and aggravation of heart failure, each in one patient, respectively. Four (57.1 %) patients had a history or postoperative recurrence of cardioembolic stroke. Median NIHSS at 1 month was 2 (range, 0-30). Median mRS at 3 months was 2 (range, 0-5). Five patients (71.4 %) had a favorable outcome (mRS2).

CONCLUSIONS

Cervical surgical embolectomy for acute extracranial ICA occlusion resulted in a high complete recanalization rate with an acceptable safety profile. A possible association between severe cardiac illness and huge embolus occluding proximal large artery was suggested.

Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke

BACKGROUND

Among patients with acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, less than 40% regain functional independence when treated with intravenous tissue plasminogen activator (t-PA) alone. Thrombectomy with the use of a stent retriever, in addition to intravenous t-PA, increases reperfusion rates and may improve long-term functional outcome.

METHODS

We randomly assigned eligible patients with stroke who were receiving or had received intravenous t-PA to continue with t-PA alone (control group) or to undergo endovascular thrombectomy with the use of a stent retriever within 6 hours after symptom onset (intervention group). Patients had confirmed occlusions in the proximal anterior intracranial circulation and an absence of large ischemic-core lesions. The primary outcome was the severity of global disability at 90 days, as assessed by means of the modified Rankin scale (with scores ranging from 0 [no symptoms] to 6 [death]).

RESULTS

The study was stopped early because of efficacy. At 39 centers, 196 patients underwent randomization (98 patients in each group). In the intervention group, the median time from qualifying imaging to groin puncture was 57 minutes, and the rate of substantial reperfusion at the end of the procedure was 88%. Thrombectomy with the stent retriever plus intravenous t-PA reduced disability at 90 days over the entire range of scores on the modified Rankin scale (P<0.001). The rate of functional independence (modified Rankin scale score, 0 to 2) was higher in the intervention group than in the control group (60% vs. 35%, P<0.001). There were no significant between-group differences in 90-day mortality (9% vs. 12%, P=0.50) or symptomatic intracranial hemorrhage (0% vs. 3%, P=0.12).

CONCLUSIONS

In patients receiving intravenous t-PA for acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, thrombectomy with a stent retriever within 6 hours after onset improved functional outcomes at 90 days. (Funded by Covidien; SWIFT PRIME ClinicalTrials.gov number, NCT01657461.).