Bivalirudin as a substitute for heparin in neurointervention for patients with heparin-induced thrombocytopenia

OBJECTIVES

Heparin-induced thrombocytopenia is a known complication of heparin exposure with potentially life-threatening sequelae. Direct thrombin inhibitors can be substituted for heparin in patients with heparin-induced thrombocytopenia that require anticoagulation. However, the use of direct thrombin inhibitors as a substitute for heparin has not been widely reported in the neuroendovascular literature.

MATERIALS AND METHODS

Here we report the first use of the direct thrombin inhibitor bivalirudin in a neuroendovascular procedure as a substitute for heparin in a patient with a ruptured pseudoaneurysm and heparin-induced thrombocytopenia, and review the literature on the use of bivalirudin and argatroban for such patients.

RESULTS

Bivalirudin was safely and effectively used in the case reported, with no thrombotic or hemorrhagic complications. Our literature review revealed a paucity of studies on the use of heparin alternatives, including bivalirudin, in neuroendovascular procedures in patients with heparin-induced thrombocytopenia.

CONCLUSIONS

Heparin-induced thrombocytopenia is an important iatrogenic disease process in patients undergoing neuroendovascular procedures, and developing protocols to diagnose and manage heparin-induced thrombocytopenia is important for healthcare systems. While further research needs to be done to establish the full range of anticoagulation options to substitute for heparin, our case indicates bivalirudin as a potential candidate.

Bridging the gap: robotic applications in cerebral aneurysms neurointerventions - a systematic review

Cerebral aneurysm is a life-threatening condition, which requires high precision during the neurosurgical procedures. Increasing progress of evaluating modern devices in medicine have led to common usage of robotic systems in many fields, including cranial aneurysm operations. However, currently no systematic review describes up-to date knowledge of this topic. Following PRISMA guidelines, we have independently screened and extracted works from seven databases. Only studies fulfilling inclusion criteria were presented in this study. Device used, operation time, complications, aneurysm type and patient demographics were extracted from each work. We identified a total of 995 articles from databases. We have found six original works and one supplementary article eligible for this synthesis. Majority of works (4/6) have implemented CorPath GRX in cerebral aneurysm procedures. The procedures involved diverse aneurysm locations, utilizing flow diverters, stents, or coiling. One study described implementation of robot-assist on 117 patients and compared results to randomized clinical trials. One work with a small patient cohort described use of the magnetically-controlled microguidewire in the coiling procedures, without any complications. Additionally, one case-series study described use of a robotic arm for managing intraoperative aneurysm rupture. Currently, robotical devices for cerebral aneurysm treatment mainly lack jailing and haptic feedback feature. Further development of these devices will certainly be beneficial for operators and patients, allowing for more precise and remote surgeries.

Endovascular Management of a Basilar Artery Pseudoaneurysm After Iatrogenic Injury During Endoscopic Third Ventriculostomy: Case Report

Endoscopic third ventriculostomy (ETV) is a well-established neurosurgical procedure. However, it carries risks of intraoperative complications, among which major vascular injury is the most dangerous. Reportedly, prominent bleeding during ETV has been noted in <1% of cases. Herein, we describe a case of a 34-year-old woman with occlusive hydrocephalus caused by a quadrigeminal cistern arachnoid cyst, who developed a pseudoaneurysm after injury of the basilar artery apex during ETV. Complete obliteration of the pseudoaneurysm with endovascular balloon-assisted coiling was done on the first postoperative day, and the patient demonstrated gradual recovery, but approximately 4 weeks later, she suffered massive rebleeding, seemingly due to rupture of the weak pseudoaneurysm wall, which resulted in her death. Careful evaluation of sagittal T2-weighted magnetic resonance images before ETV may be invaluable for assessment of the basilar artery position in relation to the third ventricle floor. In addition, use of a blunt surgical instrument (instead of a sharp one or cautery) for fenestration may be safer for prevention of arterial injury. Finally, special care should be applied in cases with an opaque third ventricle floor and inability to visualize the basilar artery during ETV.

Endovascular Treatment of Basilar Bifurcation Aneurysms With PulseRider-Assisted Coiling: 2-Dimensional Operative Video

Wide-necked bifurcation aneurysms pose technical and anatomical challenges to endovascular treatment, which make the simpler assisted (balloon or single stent) coiling techniques less effective.1 Consequently, unique endovascular solutions to treat such aneurysms have been devised.2,3 One such device is PulseRider (Cerenovus, New Brunswick, New Jersey), which is designed to provide neck support for a coil mass while protecting the bifurcation.3 The device comprises a body or stem that is deployed in the parent artery and a saddle component that sits at the aneurysm neck to keep the coil mass away from the bifurcation. There are several technical nuances involved in successful use of the device during positioning, deployment, and detachment.3 We present a surgical video detailing the steps of PulseRider-assisted coiling of unruptured basilar bifurcation (or basilar apex) aneurysms. The first case highlights index treatment at diagnosis and the second showcases treatment of a recurrent basilar apex aneurysm. Both patients provided informed consent to the procedure. We also briefly discuss the rationale for treating basilar apex aneurysms.4,5.

Imaging for Treated Aneurysms (Including Clipping, Coiling, Stents, Flow Diverters)

Intracranial aneurysms are common in the adult population and carry a risk of rupture leading to catastrophic subarachnoid hemorrhage. Treatment of aneurysms has evolved significantly, with the introduction of new techniques and devices for minimally invasive and endovascular approaches. Follow-up imaging after aneurysm treatment is standard of care to monitor for recurrence or other complications, and the preferred imaging modality and schedule for follow-up are areas of active research. The modality and follow-up schedule should be tailored to treatment technique, aneurysm characteristics, and patient factors.

Optimal timing and safety of the external ventricular drainage in patients with high-grade aneurysmal subarachnoid hemorrhage treated with endovascular coiling

The presented retrospective analysis has evaluated the optimal timing and safety of external ventricular drainage (EVD) for acute hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH). The study cohort comprised 102 patients, 49 of whom underwent EVD at 3-120 h (mean, 16 h) after the clinical onset of aSAH, either before (N = 27) or after (N = 22) ruptured aneurysm coiling. Among those treated with EVD, favorable and fair outcomes at discharge (modified Rankin Scale [mRS] scores 0-3) were noted in 14 (29%) and unfavorable (mRS scores 4-6) in 35 (71%). The former was more common among women (P = 0.019) and patients without chronic arterial hypertension (P = 0.028). The cut-off value for optimal timing of EVD was defined at 13 h after the onset of aSAH. Favorable and fair outcomes were more frequent after early (≤13 h; N = 30) than late (>13 h; N = 19) EVD (40% vs. 11%; P = 0.026), whereas did not differ significantly between those in whom such procedure was done before or after ruptured aneurysm coiling (19% vs. 41%; P = 0.083). In the entire study cohort, 2 patients had re-rupture of the aneurysm, and while both of them were treated with EVD, neither case of complication was directly associated with the procedure and, in fact, preceded it. In conclusion, EVD for management of acute hydrocephalus in patients with high-grade aSAH should be preferably applied within 13 h after the clinical onset of stroke, which may be considered sufficiently safe regardless whether it is performed before or after ruptured aneurysm coiling.

Three-dimensional aneurysm volume measurements show no correlation between coil packing density and recurrence

Objective

Endovascular treatment is the mainstay therapy for brain aneurysms. About 15% of patients need re-treatment within six months due to early recanalization. In this study, we investigate risk factors associated with treatment failure.

Methods

This retrospective cohort study includes endovascularly treated aneurysm cases between July 2012 and December 2015 at the University of California Davis Medical Center with pre-treatment and early post-treatment imaging. Thin cut 3D aneurysm volume rendering was used for morphologic analyses. Univariate and bivariate analyses were conducted to evaluate differences between patients and clinical factors by treatment failure.

Results

Of the 50 patients who met the inclusion criteria, 41 (82.0%) were female, with an average age of 61 years. Most aneurysms were on the anterior communicating artery (40%) or posterior communicating artery (22.0%), and 34 (68%) aneurysms were ruptured. Early treatment failure was observed in 14 (28.0%) of endovascularly treated patients. Raymond-Roy class (RRC) was significantly associated with treatment failure (p = 0.0052), with 10 out of the 14 cases (71.4%) with early recanalization having an RRC of 3. Coil packing density did not associate with aneurysm recanalization (p = 0.61).

Conclusion

In our single institution series, patient characteristics, aneurysm characteristics, or coil packing density did not affect early aneurysm recanalization. RRC was the best predictor of early recanalization; however, further confirmation with additional studies are required. Although this study focused on early treatment failure, late recanalization has been shown with longer follow up. Further investigation into factors associated with late treatment failure will need further investigation. New intrasaccular devices and flow diverters will also likely play a role in reducing recurrence in the future as these treatments gain usage.

Balloon-Assisted Cannulation for Difficult Anterior Cerebral Artery Access

The anterior communicating artery is a common location for intracranial aneurysms. Compared to surgical clipping, endovascular coiling has been shown to improve outcomes for patients with ruptured aneurysms and we have seen a paradigm shift favoring this technique for treating aneurysms. Access to the anterior cerebral artery can be challenging, especially in patients with tortuous anatomy or subarachnoid hemorrhage or in patients presenting with vasospasm. We present a technique for cannulating the anterior cerebral artery using a balloon inflated in the proximal middle cerebral artery as a rebound surface.

Microcatheter shaping using intravascular placement during intracranial aneurysm coiling

Background The selection of a pre-shaped microcatheter or a shaping method must be carefully considered for successful aneurysm coiling. The objective of this report is to verify the use of intravascular placement to establish an appropriate microcatheter shape. Methods Fifteen patients (15 aneurysms) were included in this study because of the predicted difficulty of microcatheter insertion and stabilisation. The SL-10 straight microcatheter was inserted into the parent artery until the tip of the catheter passed through the neck of the aneurysm. After 5 minutes, the microcatheter was pulled out and the shape acquired from intravascular placement was confirmed and compared with the three-dimensional rotational angiography. In addition, the microcatheter tip was steam-shaped for coiling and coil embolisation was performed. A silicone flow model was also used to confirm our findings. The first experiment compared the bend angle in four different microcatheters placed in the model for 5 minutes. In the second experiment, the SL-10 straight microcatheter was placed in the model, and the bend angle was measured at 2.5, 5, 7.5 and 10 minutes to observe the changes in bend angle over time. Results The SL-10 straight microcatheter, in place for 5 minutes, acquired a shape similar to the patient's own vessel. Among the 15 patients included, 13 were treated using an intravascular shaped microcatheter. In the flow model experiments, the SL-10 most easily acquired the vessel shape, and the shape change stabilised after 5 minutes. Conclusion Shaping the SL-10 straight microcatheter using intravascular placement is an effective shaping method for aneurysm coil embolisation.

Management of aneurysmal subarachnoid haemorrhage with intracerebral hematoma: Is there an indication for coiling first? Study of 44 cases

BACKGROUND

Aneurysmal subarachnoid haemorrhage (ASH) with intracerebral hematoma (ICH) has a poor prognosis. The treatment is to secure the aneurysm and do an ICH evacuation.

OBJECTIVE

The aim of the study was to determine if aneurysm coiling followed by ICH evacuation is a viable alternative treatment compared to exclusive surgery, regardless of the clinical or paraclinical presentations.

METHODS

A retrospective study was conducted between 2004 and 2014, which included 44 patients. The patients were divided up in four groups. Two were principal groups: The clipped group (aneurysm clipping with ICH evacuation) and the coiled group (aneurysm coiling, followed by ICH evacuation); and two were subgroups of the latter: Aneurysm coiling with ICH evacuation after 24 hours and ICH evacuation followed by aneurysm coiling. We studied the demographic and radiologic characteristics, and the 3-month outcome.

RESULTS

We included 17 patients in the coiled group: The outcome was better for the patients with World Federation of Neurosurgery (WFNS) scores of 1, 2 and 3; compared to the patients with WFNS scores 4 and 5. We included 16 patients in the clipped group: The outcome was better, compared the coiled group, for those patients with WFNS scores 4 and 5. Six patients were treated with aneurysm coiling, followed by ICH evacuation after 24 hours: 33% had a good outcome. Five patients were treated by ICH evacuation, followed by aneurysm coiling: None had a good outcome.

CONCLUSIONS

It was necessary to realise a prospective study to compare the outcomes of patients with WFNS scores of 1, 2 or 3; between those with aneurysm coiling followed by ICH evacuation and aneurysm clipping with ICH evacuation, to determine the potential of using the coiling first, for these patients.

Intraarterial tirofiban thrombolysis for thromboembolisms during coil embolization for ruptured intracranial aneurysms

OBJECTIVE

Thromboembolus can occur during endovascular coil embolization. The aim of our study was to show our experience of intraarterial (IA) tirofiban infusion for thromboembolism during coil embolization for ruptured intracranial aneurysms.

METHODS

This retrospective analysis was conducted in 64 patients with ruptured aneurysms who had emergent endovascular coil embolization from May 2007 to April 2011 at a single institute. Thromboembolic events were found in ten patients (15.6%). Anticoagulation treatment with intravenous heparin was started after the first coil deployment in ruptured aneurysmal sac. When a thrombus or embolus was found during the procedure, we tried to resolve them without delay with an initial dosage of 0.3 mg of tirofiban up to 1.2 mg.

RESULTS

Three patients of four with total occlusion had recanalizations of thrombolysis in myocardial infarction (TIMI) grade III and five of six with partial occlusion had TIMI grade III recanalizations. Eight patients showed good recovery, with modified Rankin Scale (mRS) score of 0 and one showed poor outcome (mRS 3 and 6). There was no hemorrhagic or hematologic complication.

CONCLUSION

IA tirofiban can be feasible when thromboembolic clots are found during coil embolization in order to get prompt recanalization, even in patients with subarachnoid hemorrhage.