Rescue treatment of thromboembolic complications during endovascular treatment of cerebral aneurysms: a meta-analysis

Thrombectomy Plus Intra-Arterial Thrombolysis Versus Thrombectomy for Acute Large Vessel Occlusions: a Matched-Control Study

AIM

We conducted a matched-control analysis to compare the outcomes of large vessel occlusion (LVO) patients treated with mechanical thrombectomy (MT) plus Intra-arterial thrombolysis (IAT) versus those treated with MT alone.

METHODS

The subjects of this study were chosen from ANGEL-ACT registry. All patients who received MT were identified and categorized into two groups: "MT + IAT" and "MT," based on whether or not they received additional intra-arterial medication IAT during the MT procedure. After being subjected to 1:1 propensity score matching, the outcome measures, including modified Rankin Scale (mRS) score at 90 days, successful recanalization at the final angiogram, symptomatic intracranial hemorrhage (sICH) within 36 h, and death within 90 days, were compared.

RESULTS

The study encompassed a total of 1607 patients, with 641 individuals assigned to the MT + IAT group and 966 to the MT group. After applying propensity score matching, a total of 524 pairs were identified for comparison. The results indicated that there were no significant differences between the two groups with regard to the modified Rankin Scale (mRS) score (median: 3 vs. 3 points; P = 0.83), successful recanalization (89.9 vs. 88.9%; P = 0.62), sICH (8.3 vs. 8.7%; P = 0.79), and death (15.5 vs. 16.4%; P = 0.70).

CONCLUSIONS

IAT during MT does not confer an elevated risk of sICH or mortality. Furthermore, the combination of MT and IAT may produce comparable functional outcomes in comparison to MT alone, when treating acute LVO patients.

Direct Aspiration Thrombectomy in the Management of Procedural Thromboembolic Complications Related to Endovascular Brain Aneurysm Treatment

Despite growing evidence over the last few years of the efficacy and safety of direct thrombus aspiration using a large bore distal access catheter as a type of mechanical thrombectomy procedure in acute stroke large-vessel occlusion patients, the experience and evidence of this technique for managing thromboembolic complications in endovascular aneurysm treatment is still limited and little research is available regarding this topic. We present a case of a thromboembolic occlusion of the left middle cerebral artery during the preprocedural angiograms of a large and fusiform left internal carotid artery aneurysm. This complication was successfully managed by navigating an already-placed distal access catheter intended for support during the opening of the flow-diverting stent; therefore, the thrombus was manually aspirated for two minutes, and Thrombolysis in Cerebral Infarction (TICI) scale 3 flow was restored. This case should encourage the use of a distal access catheter, already placed for aneurysm treatment, to perform zero-delay direct thrombus aspiration as a rescue approach for thromboembolic complications during endovascular treatments.

Use of Glycoprotein IIb-IIIa Inhibitors in Patients Undergoing Carotid Artery Stenting in the Vascular Quality Initiative

BACKGROUND

Antiplatelet therapies with thromboxane inhibitors and adenosine 5'-diphosphate antagonists have been widely used following carotid artery stenting (CAS). However, these therapies may not apply to patients who are intolerant or present acutely. Glycoprotein IIb/IIIa inhibitors (GPI) are a proposed alternative therapy in these patients; however, their use has been limited due to concerns of increased risk for intracranial bleeding. Thus, this study aims to assess the safety profile of GPI in patients undergoing CAS.

METHODS

All patients undergoing CAS in the Society of Vascular Surgery - Vascular Quality Initiative database from 2012 to 2021 was included and grouped into GPI versus non-GPI therapy (control). The primary outcome was in-hospital stroke or death, and secondary outcomes included in-hospital stroke/transient ischemic attack (TIA), death, myocardial infarction, and intracranial hemorrhage (ICH)/seizure. Patients were stratified by surgical approach (Transcarotid artery revascularization using flow reversal (TCAR) and transfemoral carotid artery stenting), and stepwise backward logistic regression analysis was conducted to evaluate major primary and secondary outcomes.

RESULTS

A total of 50,628 patients underwent carotid revascularization. Of these, 4.4% of the patients received GPI. Mean age was similar between control versus GPI (71.35(9.67) vs. 71.36(10.20) years). Compared to the control group, patients who receive GPI are less likely to be on optimal medical therapy, including aspirin (83.0% vs. 88.1%), P2Y12 inhibitor (73.0% vs. 82.7%), and statin (82.3% vs. 86.0%) (All P < 0.05). In addition, patients in the GPI group were more likely to undergo TCAR for carotid revascularization (52.2% vs. 48.4%) for emergent/urgent (29.4% vs. 16.8%) and symptomatic indications (55.5% vs. 49.7%) (All P < 0.001). After stratifying by surgical approach, if patients underwent TFCAS and received a GPI, they were at increased odds of developing stroke/death (1.77(1.25-2.51)), death (odds ratio (OR) (95% CI): 1.67(1.07-2.61)), stroke/TIA (OR (95% confidence interval (CI)): 1.65(1.09-2.51)), and ICH/seizure (OR (95% CI): 2.13(1.23-3.68)) (All P < 0.05). No difference was seen in outcomes between the 2 groups if undergoing TCAR.

CONCLUSIONS

Patients who receive GPI were more likely to be symptomatic at presentation and less likely to be medically optimized before their carotid revascularization. Transfemoral access in patients receiving GPI was associated with increased odds of morbidity and mortality. However, this was not observed if undergoing TCAR. TCAR can be considered for its overall favorable results in high-risk patients who are not medically optimized.

Risk factors for intraoperative in-stent thrombosis during stent-assisted coiling of paraclinoid aneurysms

Objectives

To identify independent risk factors for intraoperative in-stent thrombosis (IST) in paraclinoid aneurysms (PAs).

Methods

172 PA patents undergoing stent-assisted coiling (SAC) were divided into an IST group (n = 12) and a non-IST group (n = 160). Clinical characteristics, aneurysm morphologies, and laboratory parameters were measured. We performed independent t tests (for normally distributed data) or non-parametric tests (for non-normally distributed data) to compare continuous parameters. Multivariate logistic regression analysis with a stepwise forward method was conducted to determine independent risk factors. Receiver operating characteristic curves were generated, and the Delong test was employed for comparisons.

Results

Independent risk factors for IST included size ratio (SR) (p < 0.001, odds ratio [OR] = 3.909, confidence interval [CI] = 1.925-7.939), adenosine diphosphate (ADP) inhibition (p = 0.028, OR = 0.967, CI = 0.938-0.996), and reaction time (R) (p = 0.006, OR = 0.326, CI = 0.147-0.725). The combined factors (SR, ADP inhibition, and R) exhibited area under the curves of 0.870, 0.720, 0.716, and 0.697, with cutoff values of 2.46, 69.90%, and 4.65, respectively.

Conclusion

The SR, ADP inhibition, and R values were independent risk factors for the IST in the PAs undergoing SAC. For PAs with a large SR, surgeons could prepare for long-term dual antiplatelet therapy before SAC.

Local thrombolytics via balloon-assisted intra-arterial infusion as rescue therapy for thromboembolism during endovascular coil embolisation

Thromboembolism is the most frequent complication of coil embolisation for intracranial aneurysm. Complications of thromboembolism can lead to stroke and have a serious impact on sequelae and mortality, necessitating appropriate rescue therapy. Here, we succeeded in recanalisation of an occluded stent by balloon-assisted local infusion of a thrombolytic agent following stent-assisted coil embolisation of an unruptured posterior communicating artery aneurysm. This method involves inflating a microballoon just distal to the occluded vessel and then administering a thrombolytic agent through a microcatheter. This technique may increase the rate of vessel reopening by maximising the local drug concentration. This method can be applied to any type of thrombolytic agent and helps reduce the dose of systemic drugs, which might decrease the incidence of haemorrhagic complications. Balloon-assisted intra-arterial thrombolytic infusion for an occluded vessel during endovascular coil embolisation could offer an alternative rescue therapy when conventional thrombolytic agent administration fails to improve thromboembolism.

Antiplatelet Therapy in Neurointervention

The aim of this review is to provide an overview of the use of antiplatelet medication in neurointervention, with a focus on the clinical indications for antiplatelet use in both preventing and reducing platelet aggregation. This review will cover current antiplatelet medications, pharmacokinetics, and pharmacodynamics. We will provide an overview of different endovascular devices and discuss the antiplatelet regimes in neurointervention, highlighting gaps in evidence and scope for future studies.Two randomized controlled trials have evaluated antiplatelet use in the setting of acute large vessel occlusion stroke, with neither demonstrating benefit in their overall cohorts. Evidence on antiplatelet medication for both acute and elective stenting for acute stroke and treatment of cerebral aneurysms is currently based on large case series, and practice in neurointervention has increasingly utilized dual antiplatelet regimes with clopidogrel and second-line agents like prasugrel and ticagrelor. Clopidogrel function testing has an increasing role in neurointerventional procedures, particularly for high metal surface area stents such as the braided flow diverter type stents. Intravenous glycoprotein IIB/IIIA inhibitors have been utilized for both acute bridging and rescue therapy.Antiplatelet decision making is complex, and there are few randomized control trials to guide clinical practice. Comparative trials to guide decision making remain important in both the acute and elective settings. Standardised protocols incorporating platelet function testing may play a role in assisting decision making until more robust clinical evidence is available, particularly in the context of acute neurointerventional stenting for stroke and ruptured cerebral aneurysms.

Antithrombotic therapies for neurointerventional surgery: a 2021 French comprehensive national survey

BACKGROUND

Neurointerventionists lack guidelines for the use of antithrombotic therapies in their clinical practice; consequently, there is likely to be significant heterogeneity in antithrombotic use between centers. Through a nationwide survey, we aimed to obtain an exhaustive cross-sectional overview of antithrombotic use in neurointerventional procedures in France.

METHODS

In April 2021, French neurointerventional surgery centers were invited to participate in a nationwide 51-question survey disseminated through an active trainee-led research collaborative network (the JENI-RC).

RESULTS

All 40 centers answered the survey. Fifty-one percent of centers reported using ticagrelor and 43% used clopidogrel as premedication before intracranial stenting. For flow diversion treatment, dual antiplatelet therapy was maintained for 3 or 6 months in 39% and 53% of centers, respectively, and aspirin was prescribed for 12 months or more than 12 months in 63% and 26% of centers, respectively. For unruptured aneurysms, the most common heparin bolus dose was 50 IU/kg (59%), and only 35% of centers monitored heparin activity for dose adjustment. Tirofiban was used in 64% of centers to treat thromboembolic complications. Fifteen percent of these comprehensive stroke centers reported using tenecteplase to treat acute ischemic strokes. Cangrelor appeared as an emergent drug in specific indications.

CONCLUSION

This nationwide survey highlights the important heterogeneity in clinical practices across centers. There is a pressing need for trials and guidelines to further evaluate and harmonize antithrombotic regimens in the neurointerventional field.

An Updated Review on Glycoprotein IIb/IIIa Inhibitors as Antiplatelet Agents: Basic and Clinical Perspectives

The glycoprotein (GP) IIb/IIIa receptor is found integrin present in platelet aggregations. GP IIb/IIIa antagonists interfere with platelet cross-linking and platelet-derived thrombus formation through the competition with fibrinogen and von Willebrand factor. Currently, three parenteral GP IIb/IIIa competitors (tirofiban, eptifibatide, and abciximab) are approved for clinical use in patients affected by percutaneous coronary interventions (PCI) in the location of acute coronary syndrome (ACS). GP IIb/IIIa antagonists have their mechanism of action in platelet aggregation prevention, distal thromboembolism, and thrombus formation, whereas the initial platelet binding to damage vascular areas is preserved. This work is aimed to provide a comprehensive review of the significance of GP IIb/IIIa inhibitors as a sort of antiplatelet agent. Their mechanism of action is based on factors that affect their efficacy. On the other hand, drugs that inhibit GP IIb/IIIa already approved by the FDA were reviewed in detail. Results from major clinical trials and regulatory practices and guidelines to deal with GP IIb/IIIa inhibitors were deeply investigated. The cardiovascular pathology and neuro-interventional surgical application of GP IIb/IIIa inhibitors as a class of antiplatelet agents were developed in detail. The therapeutic risk/benefit balance of currently available GP IIb/IIa receptor antagonists is not yet well elucidated in patients with ACS who are not clinically evaluated regularly for early cardiovascular revascularization. On the other hand, in patients who have benefited from PCI, the antiplatelet therapy intensification by the addition of a GP IIb/IIIa receptor antagonist (intravenously) may be an appropriate therapeutic strategy in reducing the occurrence of risks of thrombotic complications related to the intervention. Development of GP IIb/IIIa inhibitors with oral administration has the potential to include short-term antiplatelet benefits compared with intravenous GP IIb/IIIa inhibitors for long-term secondary preventive therapy in cardiovascular disease. But studies showed that long-term oral administration of GP IIb/IIIa receptor inhibitors has been ineffective in preventing ischemic events. Paradoxically, they have been linked to a high risk of side effects by producing prothrombotic and pro-inflammatory events.

Effect of antiplatelet treatment on aneurysmal subarachnoid hemorrhage patients after endovascular treatment: a systematic review with meta-analysis

Antiplatelet treatment (APT) has been reported to be used in some patients with aneurysmal subarachnoid hemorrhage (aSAH) after endovascular treatment, but there is controversy among different studies regarding its clinical effects. This study intends to conduct a meta-analysis to evaluate the impact of APT on aSAH patients after endovascular treatment. The PubMed, EMBASE, and Cochrane Library databases were systematically searched up to January 2022 for eligible English publications. Quality assessment was conducted for the included studies. Publication bias and heterogeneity were assessed by Egger's test and the I² statistic, respectively. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated by meta-analysis. Robustness was checked by subgroup and sensitivity analyses. In total, 597 and 522 patients with and without APT, respectively, in 5 retrospective studies were retained for the meta-analysis. Pooled analyses showed that the APT group had a lower mortality (41/499 [8%] versus 56/402 [14%]; OR = 0.533; 95% CI, 0.347-0.820; P = 0.004) and a higher proportion of favorable clinical outcomes (400/532 [75%] versus 266/421 [63%]; OR = 1.801; 95% CI, 1.359-2.414; P = 0.000) than the control group. There was no significant difference in the incidence of hemorrhagic complications (39/564 [7%] versus 26/503 [5%]; OR = 1.386; 95% CI, 0.825-2.329; P = 0.218) between groups. Although the incidence of delayed cerebral ischemia (DCI) was significantly lower in the APT group (65/512 [13%] versus 105/447 [23%]; OR = 0.325; 95% CI, 0.107-0.988; P = 0.048), it showed substantial heterogeneity (I² = 64.7%). Subsequent sensitivity analysis suggested that the meta-analysis was robust. Subgroup analyses revealed that long-term (> 2 weeks) APT (60/479 [13%] versus 103/428 [24%]; OR = 0.212; 95% CI, 0.056-0.806; P = 0.023) significantly reduced the DCI rate and that different grouping methods in the included studies may be a source of heterogeneity. In the absence of randomized controlled trials, a meta-analysis of retrospective studies suggested that APT was associated with reduced mortality and better functional outcomes in aSAH patients after endovascular treatment without an increased incidence of hemorrhagic complications. Long-term APT was also associated with a decrease in the incidence of DCI. Well-designed randomized controlled trials are warranted and updated meta-analyses are needed to verify our findings.

Postprocedural Thrombosis following Endovascular Treatment of Intracranial Aneurysm with Flow Diverters or Coiling: A Histologic Study

Endovascular treatment of aneurysms with flow diverters or coiling is sometimes complicated by intraprocedural or postprocedural thrombosis along or within the devices. Thrombus composition and structure associated with such complications may provide insights into mechanisms of thrombus formation and clinical strategies to remove the thrombus. We present a retrospective histopathologic study of 4 patients who underwent mechanical thrombectomy due to acute occlusion of either implanted flow diverter devices or along coils during the treatment of intracranial aneurysm.

Glycoprotein IIb/IIIa inhibitors for the neurointerventionalist

Antiplatelet therapies are commonly used in neurointerventional procedures. However, specific guidelines for their use in these settings is lacking and it can often be difficult to balance the potential risks and benefits of these medications. Considering the continued growth and adoption of neurointerventional procedures, it is crucial to understand the properties of these agents in order to use them safely. Large-scale clinical trials are still needed to clarify many of these aspects for this emerging field. However, the existing literature already provides insight into which antiplatelet drugs are of benefit to the neurointerventionalist as well as their associated risks of ischemic and hemorrhagic complications. Hence, this review focuses on the applications of GPIIb/IIIA inhibitors to neurointerventional procedures.

Mechanical clot dissolution technique for surgical clip-related occlusions: An emergent triple-step approach

Cerebral ischemia following clipping of cerebral aneurysms constitutes major cause of morbidity and mortality. Clip-related injury to vessel, postoperative clip rotation, prolonged temporary occlusion, intraoperative rupture, and vasospasm are some etiological factors compromising forward flow in parent or branch vessel. On suspicion of compromised forward flow, immediate intraoperative evaluation is done to detect the cause of vascular compromise and further management is done by microsurgical or endovascular means. We describe a case of ruptured distal anterior cerebral artery (ACA) aneurysm complicated by occlusion of ACA after surgical clipping. The patient was managed by endovascular means by combined technique of intra-arterial nimodipine, antiplatelet infusion, and mechanical clot disruption using J-tip microwire.

Mechanisms of fibrinolysis resistance and potential targets for thrombolysis in acute ischaemic stroke: lessons from retrieved stroke emboli

There has been growing interest and insight into the histological composition of retrieved stroke emboli. One of the main focuses of the stroke clot analysis literature has been the implications of clot composition on mechanical thrombectomy procedures. However, the holy grail of clot analysis may not be in the field of clot–device interaction, but rather, in understanding mechanisms of fibrinolysis resistance. The mechanisms underlying the low response to fibrinolytic therapy, even with the newer, more powerful agents, remain poorly understood. While factors such as embolus size, location and collateral status influence alteplase delivery and recanalisation rates; compositional analyses focused on histological and ultrastructural characteristics offer unique insights into mechanisms of alteplase resistance. In this review, we strive to provide comprehensive review of current knowledge on clot composition and ultrastructural analyses that help explain resistance to fibrinolysis.

Bailout stentectomy of 47 self-expandable intracranial stents

Background

Self-expanding stents are increasingly being deployed for stent-assisted coiling or flow diversion of intracranial aneurysms. Complications related to stent misbehavior may arise, however, including lack of expansion, device displacement, or parent vessel thrombosis. We present our experience of various stent removal techniques (stentectomy) with a focus on technical and clinical outcomes.

Methods

Stentectomy was attempted either with a single device, including the Alligator, Microsnare, or Solitaire, or by combining a Microsnare with a second device. Dual techniques included in this report are the Snare-over-Stentretriever technique we developed using a Microsnare and a Solitaire, and the previously described Loop-and-Snare technique using a Microsnare and a microwire. The technical success and complication rate, as well as the clinical outcome using the mRS were analyzed.

Results

Forty-seven stentectomies were attempted in 36 patients treated for 37 aneurysms. Forty-two devices (89.3%) were successfully retrieved. Single-device stentectomy was successful in 34% of cases, compared with 74% with dual-device techniques. Of the 20 patients with a thrombosed parent or efferent vessel, 17 were successfully recanalized using stentectomy. All successful stentectomy patients made a clinically uneventful recovery, except one with a minor postoperative stroke (mRS 1 at discharge). Failed stentectomy was associated with major ischemic stroke in two patients and death in one patient. There were no stentectomy-related vessel perforations or dissections.

Conclusion

While various single devices can be used to safely retrieve dysfunctional intracranial self-expandable stents, dual-device techniques are more than twice as effective, according to our experience.

Neurological complications of cardiovascular drugs

Cardiovascular drugs are used to treat arterial hypertension, hyperlipidemia, arrhythmias, heart failure, and coronary artery disease. They also include antiplatelet and anticoagulant drugs that are essential for prevention of cardiogenic embolism. Most neurologic complications of the cardiovascular drugs are minor or transient and are far outweighed by the anticipated benefits of treatment. Other neurologic complications are more serious and require early recognition and management. Overtreatment of arterial hypertension may cause lightheadedness or fatigue but often responds readily to dose adjustment or an alternative drug. Other drug complications may be more troublesome as in myalgia associated with statins or headache associated with vasodilators. The recognized bleeding risk of the antithrombotics requires careful calculation of risk/benefit ratios for individual patients. Many neurologic complications of cardiovascular drugs are well documented in clinical trials with known frequency and severity, but others are rare and recognized only in isolated case reports or small case series. This chapter draws on both sources to report the adverse effects on muscle, nerve, and brain associated with commonly used cardiovascular drugs.

Prophylactic administration of tirofiban for preventing thromboembolic events in flow diversion treatment of intracranial aneurysms

BACKGROUND

Flow diverter (FD) is widely used in the treatment of intracranial aneurysms. However, thromboembolic events (TEs) continue to be the major complications during the periprocedural phase. To evaluate the safety and efficacy of the prophylactic use of tirofiban, combined with the conventional dual antiplatelet therapy (DAT), as a new antiplatelet protocol in patients with intracranial aneurysms treated with FDs.

METHODS

At least 3-5 days before the procedure, daily DAT were administrated to the patients. Tirofiban was administered as an intravenous bolus (5 µg/kg) over a 3 min period during or immediately after FD deployment, followed by a 0.05 µg/kg/min maintenance infusion for 24-48 hours. Periprocedural TEs and hemorrhagic events (HEs) were recorded.

RESULTS

A total of 331 patients were included, including 229 (69.2%) who received tirofiban administration (tirofiban group) and 102 (30.8%) who received only DAT (non-tirofiban group). Periprocedural TEs occurred in 12 (3.6%) patients, including eight (7.8%) in the non-tirofiban group and four (1.7%) in the tirofiban group. In multivariate analysis, patients receiving tirofiban administration had significantly lower TEs as compared with those who received only DAT (P=0.004). Balloon angioplasty and longer procedure time (>137 min) were also risk factors for TEs. Also, no increase was observed in the rate of HEs related to tirofiban administration.

CONCLUSIONS

The current study suggested that prophylactic administration of tirofiban combined with conventional oral DAT seems safe and efficient for preventing TEs during FD treatment of unruptured intracranial aneurysms. Balloon angioplasty and prolonged procedure are associated with a high risk of TEs.

Antiplatelet Management for Stent-Assisted Coiling and Flow Diversion of Ruptured Intracranial Aneurysms: A DELPHI Consensus Statement

BACKGROUND AND PURPOSE

There is a paucity of data regarding antiplatelet management strategies in the setting of stent-assisted coiling/flow diversion for ruptured intracranial aneurysms. This study aimed to identify current challenges in antiplatelet management during stent-assisted coiling/flow diversion for ruptured intracranial aneurysms and to outline possible antiplatelet management strategies.

MATERIALS AND METHODS

The modified DELPHI approach with an on-line questionnaire was sent in several iterations to an international, multidisciplinary panel of 15 neurointerventionalists. The first round consisted of open-ended questions, followed by closed-ended questions in the subsequent rounds. Responses were analyzed in an anonymous fashion and summarized in the final manuscript draft. The statement received endorsement from the World Federation of Interventional and Therapeutic Neuroradiology, the Japanese Society for Neuroendovascular Therapy, and the Chinese Neurosurgical Society.

RESULTS

Data were collected from December 9, 2019, to March 13, 2020. Panel members achieved consensus that platelet function testing may not be necessary and that antiplatelet management for stent-assisted coiling and flow diversion of ruptured intracranial aneurysms can follow the same principles. Preprocedural placement of a ventricular drain was thought to be beneficial in cases with a high risk of hydrocephalus. A periprocedural dual, intravenous, antiplatelet regimen with aspirin and a glycoprotein IIb/IIIa inhibitor was preferred as a standard approach. The panel agreed that intravenous medication can be converted to oral aspirin and an oral P2Y12 inhibitor within 24 hours after the procedure.

CONCLUSIONS

More and better data on antiplatelet management of patients with ruptured intracranial aneurysms undergoing stent-assisted coiling or flow diversion are urgently needed. Panel members in this DELPHI consensus study preferred a periprocedural dual-antiplatelet regimen with aspirin and a glycoprotein IIb/IIIa inhibitor.

Safety and Efficacy of Tirofiban in Rescue Treatment for Acute Intracranial Intraprocedural Stent Thrombosis

Background and Purpose: The incidence of acute intraprocedural stent thrombosis (AIST) during stenting of intracranial atherosclerotic stenosis (ICAS) has seldom been reported and evidence regarding the treatment of AIST is lacking. We aim to investigate the incidence of AIST during stenting of ICAS in our institute, assess the preliminary efficacy and safety of rescue treatment of tirofiban for these patients.

Methods: From September 2016 to May 2019, all symptomatic ICAS patients who underwent intracranial stenting in our institute were prospectively registered into this study, of which patients with AIST were retrospectively reviewed to extract baseline characteristics, perioperative management, procedural details, angiographic, and clinical outcomes. Rescue treatment of tirofiban for AIST was assessed by recanalization of the culprit vessel and periprocedural death, hemorrhage, and ischemic stroke.

Results: Acute intraprocedural stent thrombosis developed in 12 (6.2%) patients within 30 min after stent placement of 194 patients. All 12 cases were successfully recanalized with modified Treatment in Cerebral Ischemia (mTICI) 3 and Arterial Occlusive Lesion (AOL) 3 after rescue treatment of tirofiban alone. There was no perioperative death or any hemorrhagic complication. Three patients suffered perioperative ischemic stroke.

Conclusions: We observed a non-negligible rate of AIST during intracranial stenting procedures for ICAS. Intra-arterial bolus followed by intravenous tirofiban infusion seems to be efficacious and safe for AIST during stent placement for ICAS, without increasing the rate of hemorrhagic complications and death.

Glycoprotein IIb/IIIa Inhibitors in Prevention and Rescue Treatment of Thromboembolic Complications During Endovascular Embolization of Intracranial Aneurysms

Thromboembolic complications remain a major risk of endovascular neurosurgery during the treatment of intracranial aneurysms, despite the use of therapeutic heparinization and oral antiplatelet therapy when indicated. Glycoprotein (GP) IIb/IIIa inhibitors target a nonredundant pathway of platelet aggregation following adhesion and activation. Initially established and implemented in the cardiovascular arena, this drug class has provided a new tool in the neurovascular armamentarium as well. Numerous case reports, case series, and retrospective reviews have evaluated the safety and efficacy of abciximab, eptifibatide, and tirofiban in the treatment of acute thromboembolic complications during the endovascular treatment of intracranial aneurysms. The use of this drug class has also been found to be beneficial as a prophylactic agent, providing ischemia protection during the placement of intracranial stents, flow diverters, and thrombogenic coils in the setting of subarachnoid hemorrhage and during elective aneurysmal embolization. While the current published literature clearly establishes efficacy and safety of GP IIb/IIIa inhibitors in the prevention of thromboembolic complications, there does not yet exist an established protocol for their administration in endovascular neurosurgery. This review provides a comprehensive evaluation of the current published literature pertaining to the use of all available GP IIb/IIIa inhibitors for thromboembolic complications, providing recommendations for dosing and administration of abciximab, eptifibatide, and tirofiban based on previously published rates of efficacy and intracranial hemorrhage.

Saccular or dissecting aneurysms involving the basilar trunk: Endovascular treatment and clinical outcome

Objectives: Basilar artery trunk aneurysms (BTAs) are a rare pathology and difficult to treat. We present our experience regarding angiographic results and clinical outcomes for 16 BTAs treated by reconstructive endovascular treatment (EVT) using stent or balloon. Methods: Between January 2003 and December 2014, 15 patients (mean age, 58.6 years; 11 males) with 16 BTAs were enrolled. Clinical manifestation, outcomes and procedural complications were evaluated retrospectively, and follow-up angiography was performed 12 and 24 months after procedure. Results: Subarachnoid hemorrhage (SAH) developed in seven aneurysms and nine were found incidentally. In one case, SAH followed by acute infarction on pons. The location of the aneurysms was the pure basilar artery (BA) trunk in 13 and the junction of the BA and the superior cerebellar artery in 3. Reconstructive EVT was technically successful in 15 aneurysms (93.8%) and failed in one due to the difficulty of vascular access. Stent/balloon-assisted coiling was performed in 13 aneurysms and sole stent therapy in two aneurysms. One patient had periprocedural complication of acute in-stent thrombosis. All treated patients had no symptoms with the usual activities except three patients, who died from myocardial infarction, aneurysmal rebleeding, and cerebellar infarction. Angiographic follow-up was performed in nine aneurysms; three aneurysms were recanalized (33.3%) and six aneurysms had no interval change (66.7%). There was no significant event during the follow-up period (mean, 23.5 months). Conclusion: In the treatment of BTAs, reconstructive EVT may provide a feasible and safe option to microsurgery.

Safety of tirofiban and dual antiplatelet therapy in treating intracranial aneurysms

Background

Endovascular treatment of intracranial aneurysms usually involves stent-assisted coiling (SAC) and flow diverters. Glycoprotein IIb/IIIa inhibitors such as tirofiban and dual antiplatelet therapy (DAPT) are required to prevent thromboembolic complications afterwards. We sought to determine the safety of tirofiban and DAPT in these cases.

Methods

We conducted a retrospective analysis of our database for patients with intracranial aneurysms who underwent SAC or flow diversion. The tirofiban-DAPT protocol used is described. Data regarding duration of infusion, placement of external ventricular devices (EVDs), complications, haemoglobin levels and platelet count before and 24 hours after antiplatelet therapy were collected and analysed.

Results

One-hundred and forty-one patients with 148 aneurysms/procedures were included. 110 aneurysms were treated acutely and 38 electively. Minor and major haemorrhagic events were recognised in 20% (30/148) aneurysms. Only 5 (3.4%) intracerebral haemorrhages were symptomatic: 3 cortical/SAH and 2 EVD-related. The average blood volume in symptomatic haemorrhages was 24.8 cc versus 5.42 cc in asymptomatic haemorrhages (p=0.002). The rate of EVD-related haemorrhages was 15.7% (19/121) and only 2 (1.7%) were symptomatic. Most haemorrhagic events occurred in ruptured aneurysms (90.1%, p=0.01). No significant change in platelet count or haemoglobin levels before and 24 hours after administration of tirofiban and DAPT was documented. Concomitant administration of heparin did not increase haemorrhagic events.

Conclusion

The use of the GP IIb/IIIa inhibitors tirofiban and DAPT in this series was safe. Tirofiban and DAPT did not affect platelet count or haemoglobin levels and did not increase rate of symptomatic haemorrhages or thromboembolic complications.

In situ administration of abciximab for thrombus resolution during intracranial bypass surgery: case report

Abciximab is a glycoprotein IIb/IIIa receptor antagonist that functions to prevent platelet aggregation, thus reducing thrombus initiation and propagation. It has been widely used during percutaneous endovascular interventions, such as aneurysm coil embolization, angioplasty, atherectomy, and stent placement, as both a preventative and a salvage therapy. The use of abciximab in cardiac and neurosurgical procedures has been associated with a reduced incidence of ischemic complications and a decreased need for repeated intervention. In these settings, abciximab has been delivered transarterially via a microcatheter or infused intravenously for systemic administration. The authors describe novel in situ delivery of abciximab as an agent to dissolve "white clots," which are composed primarily of platelets, during an intracranial superficial temporal artery to middle cerebral artery bypass in a 28-year-old woman with severe intracranial occlusive disease. Abciximab was able to resolve multiple platelet-based clots after unsuccessful attempts with conventional clot dispersal techniques, such as heparinized saline, tissue plasminogen activator, mechanical passage of a wire through the vessel lumen, and multiple takedowns and re-anastomosis. After abciximab was administered, patency was demonstrated intraoperatively using indocyanine green dye and confirmed postoperatively at 1 and 10 months via CT angiography. The in situ use of abciximab as an agent to disperse a thrombus during intracranial bypass surgery is novel and has not previously been described in the literature, and serves as an additional tool during intracranial vessel bypass surgery.

Rescue therapy with stent retrievers for thromboembolism during endovascular treatment of intracranial aneurysms

Thromboembolism is the most frequent complication in endovascular treatment of intracranial aneurysms, causing disability and death. As stent retrievers have achieved high rates of arterial recanalization in the management of ischemic stroke, these devices were tested as rescue therapy of thromboembolism during aneurysm embolization. We retrospectively analyzed 10 consecutive patients with transprocedural arterial occlusion, treated with mechanical thrombectomy at a single center. Good angiographic recanalization was achieved in eight cases, mTICI 3, 2b and 2a in five, three and two patients, respectively, without additional complications or any deaths. Five patients showed complete recovery (mRS 0) and all patients showed improvement of disability (average mRS 1.1) over a mean follow-up period of 31 months. Eight patients had good clinical recovery, while two remained with deficits (mRS 3 and 4). The study found that the stent retriever is a valuable, rapid and effective tool for restoring blood flow, improving the safety of endovascular treatment.

Abciximab (ReoPro) Dosing Strategy for the Management of Acute Intraprocedural Thromboembolic Complications during Pipeline Flow Diversion Treatment of Intracranial Aneurysms

Background

Flow diversion with the Pipeline embolization device (PED) is an effective neuro-endovascular method and increasingly accepted for the treatment of cerebral aneurysms. Acute in situ thrombosis is a known complication of PED procedures. There is limited experience in the flow diversion literature on the use of abciximab (ReoPro) for the management of acute thrombus formation in PED cases.

Methods

Data were collected retrospectively on patients who received intra-arterial (IA) ReoPro with or without subsequent intravenous (IV) infusion during PED flow diversion treatment of intracranial aneurysms.

Results

A total of 30 cases in patients with a mean age of 56.7 years (range 36-84) and a mean aneurysm size of 8.6 mm (range 2-25) were identified to have intraprocedural thromboembolic complications during PED treatment. IA ReoPro was administered in all cases, with 20 cases receiving increments of 5-mg boluses and 10 cases receiving a 0.125 mg/kg IA bolus (half cardiac dosing). Complete or partial recanalization was achieved in 100% of the cases. IV ReoPro infusion at 0.125 μg/kg/min for 12 h was administered postprocedurally in 22 cases with a residual thrombus. Postprocedurally, 18 patients were transitioned from clopidogrel (Plavix) to prasugrel (Effient). The majority of the cases (23/30; 77%) were discharged home. Periprocedural intracranial hemorrhage was noted in 2 cases (7%) and radiographic infarct was noted in 4 cases (13%), with an overall mortality of 0% at the time of initial discharge. Clinical follow-up was available for 28/30 patients. The average duration of follow-up was 11.7 months, at which time 23/28 (82%) of the patients had a modified Rankin Scale score of 0.

Conclusions

IA ReoPro administration is an effective and safe rescue strategy for the management of acute intraprocedural thromboembolic complications during PED treatment. Using a dosing strategy of either 5-mg increments or a 0.125 mg/kg IA bolus (half cardiac dosing) can provide high rates of recanalization with low rates of hemorrhagic complications and long-term morbidity.

Two-Center Experience in the Endovascular Treatment of Ruptured and Unruptured Intracranial Aneurysms Using the WEB Device: A Retrospective Analysis

BACKGROUND AND PURPOSE

The safety and efficacy of the Woven EndoBridge (WEB) device for the treatment of cerebral aneurysms has been investigated in several studies. Our objective was to report the experience of 2 neurovascular centers with the WEB device in the treatment of broad-based intracranial aneurysms, including the technical feasibility and safety as well as short- and midterm angiographic and clinical follow-up-results.

MATERIALS AND METHODS

We performed a retrospective analysis of all ruptured and unruptured aneurysms treated with a WEB device (WEB Single-Layer and Single-Layer Sphere) between August 2014 and February 2017. Primary outcome measures included the feasibility of implantation and the angiographic outcome. Secondary outcome measures included the clinical outcome at discharge and procedural complications.

RESULTS

One hundred two aneurysms in 101 patients, including 37 (36.3%) ruptured aneurysms, were treated with the WEB device. Implantation was successful in 98 (96.1%) aneurysms. Additional devices (stents/coils) were necessary in 15.3% (15/98) of aneurysms. Procedural complications occurred in 4.9% (5/102). Of these, 4 were thromboembolic events and 1 was an intraprocedural rupture. Angiographic follow-up at 3 and 12 months was available for 79.6% (78/98) and 50.0% (49/98) of all aneurysms to date, respectively, showing a sufficient aneurysm occlusion in 80.7% (63/78) at 3 months and 77.6% (38/49) at 12 months. Delayed aneurysm ruptures have not been observed during the follow-up period to date.

CONCLUSIONS

The WEB device offers a safe and effective treatment option for broad-based intracranial aneurysms without the need for dual antiplatelet therapy.

Intra-arterial and Intravenous Tirofiban Infusion for Thromboembolism during Endovascular Coil Embolization of Cerebral Aneurysm

OBJECTIVE

Thromboembolism is the one of the most serious complications that can occur during endovascular coil embolization of cerebral aneurysm. We report on the effectiveness and safety of intra-arterial/intravenous (IA/IV) glycoprotein IIb/IIIa inhibitor (tirofiban) infusion for treating thromboembolism during endovascular coil embolization of cerebral aneurysm.

METHODS

We performed a retrospective analysis of 242 patients with ruptured or unruptured cerebral aneurysms (n=264) who underwent endovascular coil embolization from January 2011 to June 2014. Thromboembolism occurred in 20 patients (7.4%), including 14 cases of ruptured aneurysms and 6 cases of unruptured aneurysms. The most common site of aneurysms was the anterior communicating artery (n=8), followed by middle cerebral artery (n=6). When we found an enlarged thromboembolism during coil embolization, we tried to dissolve it using tirofiban administered via IA and IV loading (5 μg/kg, respectively) for 3-5 minutes followed by IV maintenance (0.08 μg/kg/min) for approximately 4-24 hours.

RESULTS

In 4 of 5 patients with total vessel occlusion, the vessel was recanalized to Thrombolysis in Cerebral Infarction Perfusion Scale (TICI) grade 3, and in 1 patient to TICI grade 2a. In 2 patients with partial vessel occlusion and 13 patients with minimal occlusion, the vessel recanalized to TICI grade 3. Irrelevant intracerebral hemorrhage was noted in 1 patient (5%), and thromboemboli-related cerebral infarction developed in 5 patients (25%), of which only 1 (5%) was symptomatic.

CONCLUSION

IA/IV infusion and IV maintenance with tirofiban appear to be an effective rescue treatment for thromboembolism during endovascular coil embolization in patients with ruptured or unruptured cerebral aneurysms.

Rescue mechanical thrombectomy using a retrievable stent for thromboembolic occlusion occurring during coil embolization of ruptured intracranial aneurysms

Objective

To examine the safety and efficacy of mechanical thrombectomy using a retrievable stent for thromboembolic occlusion occurring during coil embolization of ruptured intracranial aneurysms.

Methods

Between June 2011 and June 2015, 631 consecutive patients with ruptured intracranial aneurysms underwent coil embolization at 6 hospitals. Among 53 patients who had thromboembolic complications, 15 patients harboring 15 aneurysms underwent rescue mechanical thrombectomy with a retrievable stent for the treatment of thromboembolic occlusion during the coiling of ruptured aneurysms. The patients' clinical and radiologic outcomes were retrospectively reviewed.

Results

Of the 15 aneurysms, coiling alone was used for 13 (86.7%), and stent-assisted coiling was performed for 2 (13.3%). Thromboembolic occlusion most frequently occurred distal to the aneurysm (n=10, 66.7%), followed by proximal to the aneurysm (n=3, 20%), and at the coil−parent vessel interface (n=2, 13.3%). All patients underwent mechanical thrombectomy with a retrievable stent, including 5 patients who were initially treated with an IA tirofiban infusion. Complete recanalization (Thrombolysis in Cerebral Infarction (TICI) 3) was obtained in 13 (86.7%) and partial recanalization (TICI 2b) in 2 (13.3%). Two patients who had received IA tirofiban before mechanical thrombectomy had hemorrhagic complications. At 6 months after discharge, 9 patients had a modified Rankin Scale (mRS) score of 1, 3 patients were mRS 2, 1 patient was mRS 3, 1 patient was mRS 4, and 1 patient was mRS 6.

Conclusions

Rescue mechanical thrombectomy using a retrievable stent can be a useful treatment for thromboembolic occlusion occurring during coil embolization of ruptured intracranial aneurysms.

Intra-arterial versus intravenous abciximab therapy for thromboembolic complications of neuroendovascular procedures: case review and meta-analysis

BACKGROUND

Abciximab is used to treat thromboembolic complications of neuroendovascular procedures, but outcomes of treatment are not well defined.

OBJECTIVE

To examine the angiographic and clinical outcomes based on route of abciximab administration and degree of vessel recanalization.

MATERIALS AND METHODS

A prospectively maintained database of neuroendovascular procedures performed between January 2004 and May 2015 was retrospectively reviewed to identify cases with thromboembolic complications treated with abciximab. In these cases, route of administration, degree of vessel recanalization, and presence or absence of infarction were determined. A meta-analysis of similar cases in the literature was also performed.

RESULTS

Abciximab was administered in 0.24% (47 of 19 566) of procedures to treat thromboemboli in 59 vessels. Angiographic improvement was seen in 94% after IA therapy and 79% after IV therapy (p=0.133). In our meta-analysis of 391 treated patients, angiographic improvement was greater after IA (91.7%) than IV (77.4%) treatment (p<0.001). Postprocedural infarction occurred more frequently with distal lesions (42%) than local lesions (12%) (p=0.014), and occlusive lesions (36%) than non-occlusive lesions (4.8%) (p=0.010). Infarction was significantly less common with complete angiographic resolution (0%) than with partial or no improvement (54%) (p<0.001). Symptomatic intracranial hemorrhage occurred in 2.1%.

CONCLUSIONS

Abciximab produces a high rate of angiographic improvement and a low incidence of postprocedural infarct in neuroendovascular procedures complicated by thromboemboli. IA abciximab produces greater angiographic improvement than IV treatment. Postprocedural infarction is less common in patients with complete angiographic response than in those with partial or no response.

Neurocritical Care of Emergent Large-Vessel Occlusion: The Era of a New Standard of Care

Acute ischemic stroke continues to be one of the leading causes of morbidity and mortality worldwide. Recent advances in mechanical thrombectomy techniques combined with prereperfusion computed tomographic angiography for patient selection have revolutionized stroke care in the past year. Peri- and postinterventional neurocritical care of the patient who has had an emergent large-vessel occlusion is likely an equally important contributor to the outcome but has been relatively neglected. Critical periprocedural management issues include streamlining care to speed intervention, blood pressure optimization, reversal of anticoagulation, management of agitation, and selection of anesthetic technique (ie, general vs monitored anesthesia care). Postprocedural critical care issues that might modulate neurological outcome include blood pressure and glucose optimization, avoidance of fever or hyperoxia, fluid and nutritional management, and early integration of rehabilitation into the intensive care unit setting. In this review, we sought to lay down an evidence-based strategy for patients with acute ischemic stroke undergoing emergent endovascular reperfusion.

Stent-Assisted Coil Embolization of Intracranial Aneurysms: Complications in Acutely Ruptured versus Unruptured Aneurysms

BACKGROUND AND PURPOSE

The use of stents in the setting of SAH is controversial because of concerns about the efficacy and risk of dual antiplatelet therapy. We compare complications of stent-assisted coil embolization in patients with acutely ruptured aneurysms with complications in patients with unruptured aneurysms.

MATERIALS AND METHODS

Between February 2007 and March 2015, 45 acutely ruptured aneurysms and 47 unruptured aneurysms were treated with stent-assisted coiling. Patients with ruptured aneurysms were not pretreated with antiplatelet medication but received intravenous aspirin during the procedure. Thromboembolic events and early rebleeds were recorded.

RESULTS

In ruptured aneurysms, 9 of 45 patients had thromboembolic complications. Four patients remained asymptomatic, 4 developed infarctions, and 1 patient died. The permanent complication rate in ruptured aneurysms was 11% (95% CI, 4%-24%). Five of 45 patients (11%; 95% CI, 4%-24%) had an early rebleed from the treated aneurysm after 3-45 days, and in 4, this rebleed was fatal. In 46 patients with 47 unruptured aneurysms, thromboembolic complications occurred in 2. One patient remained asymptomatic; the other had a thalamus infarction. The complication rate in unruptured aneurysms was 2.2% (1 of 46; 95% CI, 0.01%-12%). No first-time hemorrhages occurred in 46 patients with 47 aneurysms during 6 months of follow-up.

CONCLUSIONS

The complication rate of stent-assisted coiling with early adverse events in ruptured aneurysms was 10 times higher than that in unruptured aneurysms. Early rebleed accounted for most mortality. In ruptured aneurysms, stent-assisted coil embolization is associated with increased morbidity and mortality and should only be considered when less risky options have been excluded.

Intraprocedural abciximab bolus versus pretreatment oral dual antiplatelet medication for endovascular stenting of unruptured intracranial aneurysms

Background

Standard pretreatment with dual antiplatelet medication (DAPM) was compared with a standalone intraprocedural abciximab bolus for the prevention of thromboembolic and hemorrhagic events during endovascular stenting of unruptured intracranial aneurysms.

Materials and methods

We treated 94 patients with 99 aneurysms with intracranial stenting (with or without coiling). Patients were either pretreated with DAPM daily for ≥3 days before stenting (pretreatment group) or received an abciximab bolus during or immediately after stent placement followed by postoperative DAPM (abciximab group), at the treating physician's discretion. Twenty patients underwent immediate postoperative MRI. Demographic, clinical, and radiological information and periprocedural complications were recorded.

Results

There were 52 procedures in the pretreatment group and 47 in the abciximab group. More flow-diverting stents were placed in the pretreatment group than in the abciximab group (45 vs 23, p<0.001), and the aneurysm diameter was larger (11.2±6.7 vs 8.3±4.7 mm, p=0.01). There were 11 thrombotic and 7 access site complications, with no significant difference between the groups (p>0.99 and p=0.12, respectively). There were no intracranial hemorrhages. In patients with postoperative MRI, there was no difference in the presence of diffusion-restricted lesions between groups (p=0.20). Multivariate analysis of a composite of any complication did not show significant associations with aneurysm or patient variables in either group.

Conclusions

Standalone intraprocedural abciximab bolus was not associated with an increased rate of complications compared with pretreatment with DAPM for unruptured intracranial aneurysm stenting.

Patients with subarachnoid haemorrhage from vertebrobasilar dissection: treatment with stent-in-stent technique

INTRODUCTION

Vertebrobasilar dissection is an uncommon cause of subarachnoid haemorrhage (SAH) that carries a high risk for early repeat haemorrhage. The need for rapid treatment of this disease entity is without question; however, the best method for treatment is still undetermined. Here, we present our results using the stent-in-stent technique, without coiling, for these patients and propose that it is a viable treatment strategy.

METHODS

We identified in our local database for neurointerventional therapy, between 1st October 2000 and 1st January 2014, 93 patients with potential subarachnoid haemorrhage secondary to vertebrobasilar pathology. After review of the clinical notes and imaging, 15 were found to have presented with subarachnoid haemorrhage and treated with stents alone. All dissections were spontaneous with no history of preceding trauma. The ages ranged between 46 and 71 years (mean 61 years).

RESULTS

All patients presented with Fischer grade 4 SAH and had a visible pseudoaneurysm. The pre-operative GCS varied with two patients scoring 3, one patient scoring 6 and the remaining 12 patients scoring 8 or above. All cases were subjected to stent-in-stent treatment alone. We did not experience any intra-procedural complications. In our series, eight patients had full recovery with a Glasgow Outcome Scale (GOS) of 5, three had moderate disability (GOS 4), one had severe disability (GOS 3), and three patents died, one patient from stent thrombosis or re-bleeding and two from their initial SAH.

CONCLUSION

The stent-in-stent technique represents a viable reconstructive endovascular surgical technique with a low risk of intra-procedural complication and post-operative repeat haemorrhage.