Armen Choulakian

Mechanical thrombectomy with the penumbra system for treatment of venous sinus thrombosis.

Objective Venous sinus thrombosis can be a fatal condition. When systemic anticoagulation therapy fails or is high risk, endovascular chemical thrombolysis or mechanical thrombectomy may be necessary. We report our experience using the Penumbra system (PS; Penumbra, Alameda, California, USA) in a series of four patients with venous sinus thrombosis. Methods Four patients were treated with mechanical thrombectomy using the PS for venous sinus thrombosis. Three of these patients also underwent balloon angioplasty following the PS device. Utility of this technique was evaluated by procedural success, improvement in neurological condition, avoidance of complications and follow-up imaging. Results Technical success was achieved in all four patients with restoration of flow in the occluded sinuses without the use of chemical thrombolysis. No complications were encountered during the procedure and no postprocedural complications were attributable to the thrombectomy. One patient with glioblastoma died 6 weeks after the procedure. No new intracerebral hemorrhages were caused and there was no exacerbation of pretreatment intracerebral hemorrhages. Follow-up imaging was available in all but one patient to documented continued sinus patency. Neurologic improvement was seen in all patients after thrombectomy. Two patients have returned for outpatient follow-up and both are doing well. Conclusion Endovascular treatment for venous sinus thrombosis with the PS is a safe and efficacious alternative to the other forms of mechanical thrombectomy reported in the literature. Good clinical and radiographic results can be obtained without the need for chemical thrombolysis.

Stent-assisted coil emboilization of ruptured intracranial aneurysms: A retrospective multicenter review

Background: The purpose of this study is to retrospectively review our experience with stent-assisted embolization of patients with an acutely ruptured cerebral aneurysm. Methods: Medical records and imaging were reviewed for 36 patients who underwent stent-assisted embolization of a ruptured cerebral aneurysm. Results: Seventeen patients (47%) received a preprocedural loading dose of clopidogrel and five patients (14%) received an intraprocedural dose of clopidogrel. The remaining 14 patients (36%) were treated with antiplatelet therapy following the procedure. Six (17%) stent related intraprocedural thromboembolic complications were encountered; four of these resolved (one partial, three complete) following treatment with abciximab and/or heparin during the procedure. Five of the six thromboembolic events occurred in patients who were not pretreated with clopidogrel (P = 0.043). Two patients in this series (6%) had a permanent thrombotic complication resulting in mild hemiparesis in one patient, and hemianopsia in the second. No procedure related hemorrhagic complications occurred in any patient. One patient had a spontaneous parenchymal hemorrhage contralateral to the treated aneurysm discovered 10 days after treatment. Twenty-eight patients (78%) had a Glasgow Outcome Score of 4 or better at discharge. Seven of 21 patients (33%) with angiographic follow-up required further treatment of the coiled aneurysm. Conclusion: Stent-assisted coil embolization is an option for treatment of ruptured wide neck ruptured aneurysms and for salvage treatment during unassisted embolization of ruptured aneurysms but complications and retreatment rates are higher than for routine clipping or coiling of cerebral aneurysms. Pretreatment with clopidogrel appears effective in reducing thrombotic complications without significant increasing risk of hemorrhagic complications.

Endosaccular treatment of 113 cavernous carotid artery aneurysms

Objective Cavernous carotid aneurysms (CCAs) can present with visual symptoms or with subarachnoid hemorrhage (SAH). As surgical treatment of these aneurysms can be technically challenging, endovascular management has emerged as the preferred treatment modality. Methods A retrospective review was conducted of 113 patients who underwent endosaccular treatment for CCAs. Presenting symptoms, aneurysm size, use of stent assistance, rate of thromboembolic complications, presence of SAH and angiographic follow-up were reviewed. Results 29 patients (26%) with CCAs presented with diplopia due to cranial nerve palsies. Mean aneurysm size in this group was 17 mm. Three patients (2.6%) presented with SAH with a mean aneurysm size of 15.3 mm. Mean length of stay for ruptured versus non-ruptured aneurysms was 11.7 and 1.7 days, respectively. Clinically significant thromboembolic complications occurred in four cases (3.5%). Stent assistance was required in 53 cases (47%). Of the 86 patients (76%) returning for follow-up angiography (mean 6.2 months), 58 (75%) had no residual aneurysm and 14 (12%) showed regrowth. Thirteen patients (11.5%) underwent repeat endovascular treatment. Conclusions CCAs commonly produce diplopia and cranial nerve palsies when a critical size is reached (mean 17 mm in our series). Aneurysm obliteration with internal carotid artery preservation is the preferred treatment modality and can be accomplished with coil embolization with or without stent assistance. Although recurrence and retreatment can occur, the thromboembolic risk of endovascular treatment is low. Consideration should be given to treatment of asymptomatic CCAs 15 mm or larger due to potential risks of cranial neuropathy and SAH.

Body weight: a risk factor for subtherapeutic antithrombotic therapy in neurovascular stenting

Background Patients with cervical carotid and intracranial stenting are routinely premedicated with antithrombotic agents, clopidogrel and aspirin (ASA), and intraprocedurally with heparin. The levels of antithrombotic therapy necessary for these neurovascular therapies have yet to be well defined. Method A retrospective review of 52 patients who underwent neurovascular stenting procedures was carried out. Measurements obtained intraoperatively included: activating clotting time, antiplatelet inhibition (from Accumetrics) recorded as ASA reaction units (ARU), P2Y12 reaction units (PRU), baseline (BASE), and percentage inhibition. Percentage P2Y12 platelet inhibition <20% and ARU >550 were defined as suboptimal clopidogrel and ASA responses, respectively. Results 52 patients (mean age 62.6 years) underwent stent implantation for wide necked aneurysms (28, 54%), symptomatic intracranial stenosis (13, 25%) and cervical carotid stenosis (11, 21%). Mean ARU assays were 463.0±84.7. The response was suboptimal in seven patients. For clopidogrel, the mean BASE, PRU and percentage inhibition were 374.0±54.9, 279.5±78.5 and 30.7%±22.6%, respectively. 19 patients (36.5%; p<0.01) showed suboptimal responses for percentage inhibition. Multivariate analysis showed that body weight (82.0±11 vs 73.6±14 kg; p =0.04) and body mass index were significant predictors (OR 1.18, 95% CI 1.01 to 1.18; p =0.003) in the suboptimal group. One case of intraprocedural thrombosis (2%) was observed in the suboptimal group and no cases were seen in the therapeutic group. Conclusion Data obtained in this study suggest a suboptimal clopidogrel response in patients with greater body weight and body mass index. Adjusted dosing according to weight may help achieve adequate therapeutic platelet inhibition and reactivity while decreasing thromboembolic complications.

NBCA embolization of a ruptured intraventricular distal anterior choroidal artery aneurysm in a patient with moyamoya disease

Occasionally an aneurysm is the cause of hemorrhage in patients with moyamoya disease (MMD). We present a case of a ruptured intraventricular distal anterior choroidal artery (AChA) aneurysm treated with n-butyl cyanoacrylic acid (nBCA) (Trufill nBCA Liquid Embolic, Codman Neurovascular, Raynham, Massachusetts, USA) embolization in a patient with MMD. There were no procedural complications and at 6 month follow-up she remained neurologically normal. Six month follow-up cerebral angiography showed no residual aneurysm. The endovascular route is an attractive option for many aneurysms associated with MMD as the lesions can be treated without disturbing the moyamoya collaterals. nBCA, delivered through a flow-guided microcatheter, is a good embolic agent choice when the lesion is distal on a small vessel and when distal parent artery occlusion can be tolerated. Intraventricular AChA aneurysms are well suited for this treatment strategy.

Congenital absence of the common carotid artery in a patient with a ruptured anterior communicating artery aneurysm

In a 41-year-old woman with a ruptured anterior communicating artery aneurysm, cerebral angiography incidentally showed an absence of the right common carotid artery. The right internal and external carotid artery originated from the ipsilateral inominate artery. The absence of the common carotid artery is extremely rare and association with a ruptured cerebral aneurysm is even less common. A description of the case and review of the literature are reported.

Anterior Spinal Artery Syndrome in a Patient with Vasospasm Secondary to a Ruptured Cervical Dural Arteriovenous Fistula

Spinal dural arteriovenous fistulas (DAVF) in the cervical spine are known to cause subarachnoid hemorrhage. Vasospasm after rupture of a DAVF, however, has not previously been reported.

O-024 UHC Data Indicates Higher Mortality Rate in Aneurysms Embolized with Bare Platinum Coils Compared with Polymer Enhanced Coils

Introduction Recently, ICD-9 procedure coding for hospitals has changed to reflect aneurysm embolization with either bare metal coils or polymer-enhanced coils, and 2010 was the first year that an entire calendar year of data are available from the University-Health System Consortium (UHC) Clinical Database that reflects this change. This study evaluated recent trends in preferences of coil types for treating patients diagnosed with ruptured or unruptured aneurysms. Potential differences in the average number of ICU days, percent complications and early mortality are compared according to coil type, aneurysm rupture status and hospital aneurysm embolization volume (high- vs low-volume). Methods Using data from the UHC Clinical Database from January 2010 to December 2010, we captured ruptured (ICD-9 code: 430) and unruptured (ICD-9 code: 437.3) aneurysm cases undergoing a coiling procedure (ICD-9 code: 39.75-Bare-Coils, 39.76-Polymer-Coils). Hospitals were stratified into high-volume if they embolized 50 or more cerebral aneurysms for the year; similarly, hospitals were considered low-volume if they embolized <50 aneurysms. Univariate analysis evaluated differences in the average number of ICU days, percent complications and early mortality while adjusting for coil type, aneurysm status and hospital type. Results The study queried a total of 3496 aneurysms embolized in 94 UHC member hospitals with the new coding designation. Interestingly, the top 16 hospitals in the database treated over half of all the aneurysms in the database (1801 aneurysms), and the remaining 1695 aneurysms were treated by the other 78 hospitals. Univariate analysis showed that high-volume hospitals were more likely to treat ruptured aneurysms with polymer-enhanced coils than low-volume: High volume- Bare: 57.1%, Polymer: 42.9% and low volume- Bare: 83.8%, Polymer: 16.2% (p<0.001). The overall clinical complications reported for polymer and bare coils showed no difference in either the ruptured or non-ruptured aneurysm groups. However, the number of ICU days (p=0.01), percentage of early deaths (within 2 days of treatment) (p=0.02), and the mortality index (p=0.006) were all statistically worse in the bare coil group compared to the polymer enhanced group when all 3496 aneurysms are analyzed. Conclusions UHC data from 2010 demonstrates that patients who had use of bare coils had a longer ICU stay, a higher early death rate, and a higher mortality index than those patients treated with polymer-enhanced coils. Although these treatment groups were not randomized, this data shows, in the real-world treatment environment currently, that patients treated with polymer-enhanced coils have better outcomes than those treated with bare coils in both the ruptured and non-ruptured groups.Abstract O-024 Table 1 All aneurysms Bare coils Polymer coils p Value Average ICU days 8.43 6.92 0.01 Complication rate 18.83 17.91 0.12 % of Early deaths 1.43 0.10 0.002 Mortality index 0.54 0.38 0.006

P-027 Management of intracranial artery dissections with stents: a series of 49 patients

Introduction Arterial dissections may be spontaneous or related to trauma, and patients with certain conditions, such as fibromuscular dysplasia or collagen vascular diseases, may be more pre-disposed to develop dissections. Arterial dissections in the intracranial vasculature are relatively rare and are less likely to be traumatic. When they do occur, they may lead to ischemic or embolic symptoms when there is a dissection flap or stenosis, or to subarachnoid hemorrhage or discovery of a non-ruptured, dissecting intracranial aneurysm. Methods This was a retrospective analysis of a prospectively collected database of patients with intracranial arterial dissections, who were treated with intracranial stents by a single operator over 11 years, without or with coil embolization. Patient presentation, procedural results, type of stent, clinical outcome, and delayed imaging findings were reviewed. In cases of dissection with an intimal flap, stenting alone was performed. In patients with dissecting aneurysms, a stent was used in all cases, and only those cases that had a significant saccular component had the placement of coils, in addition to the intracranial stent. Results A total of 49 patients were treated with intracranial arterial dissections. 19 of the patients presented with a dissection flap and arterial narrowing, 27 presented with a dissecting aneurysm (14 with subarachnoid hemorrhage and 13 with non-ruptured aneurysms), and three patients had a dissecting aneurysm and vessel narrowing. The average patient age was 34 years of age. The dissection location included 21 intracranial internal carotid artery (ICA), 12 vertebral artery, 6 posterior cerebral artery, 5 middle cerebral artery, 4 basilar artery, and 1 anterior cerebral artery. Patients were more likely to present with subarachnoid hemorrhage with ICA or vertebral artery dissections, and patients were more likely to present with ischemic symptoms with middle cerebral artery or basilar artery dissections. There were two thromboembolic complications (4%) related to the embolization procedure, there was one subsequent re-hemorrhage (2%) in a patient with a ruptured, blister-type, dissecting ICA aneurysm, and 1 groin access complication. Of the 30 patients who had an associated dissecting aneurysm, imaging follow-up was available in 25 patients. Of these, the recurrence rate was 20% (5 aneurysms), and all five were re-treated. Conclusions Stenting without or with coils is an effective treatment option for patients with intra-cranial arterial dissections. We recommend treatment in patients with dissection flaps that are enlarging on imaging or refractory to medical therapy, and in patients with dissecting intracranial aneurysms, due to the high rate of subarachnoid hemorrhage. Our overall complication rate was 8% for treatment, and there was a high propensity for aneurysm re-growth, with a 20% re-treatment rate.

E-050 Stent assisted coil embolization for large and giant fusiform dissecting aneurysms: a series of 38 cases

Introduction Fusiform aneurysms present a challenge for treatment since their dome to neck ratios are often less than 1. These are cases that are excluded from most aneurysm series, and prior to intracranial stents were thought not to be treatable by embolization, except by parent artery occlusion. Methods This is a retrospective analysis of a prospectively collected database of 38 patients who had stent assisted coil embolization of a large or giant fusiform aneurysms. A total of 21 patients had two telescoping stents placed and four patients had three telescoping stents. There is an analysis of the procedure related complications, re-treatments, symptomatology and delayed follow-up. Results The average aneurysm size treated was 21.4 mm (range 12–61), with an average neck of 18.6 mm. In the periprocedural period there was a 10% complication rate with two strokes and two increased cranial neuropathies. Nine of the patients required re-treatment during a mean follow-up time of 38 months. There were two deaths in the follow-up period: one due to subarachnoid hemorrhage, another presumed due to respiratory arrest. Conclusions Although stand alone flow diversion devices are being developed and evaluated, stent assisted coil embolization is an effective alternative to fusiform and fusiform dissecting aneurysms. The periprocedural complication rates are reasonable (10%), and although re-treatment is frequently necessary, the long term outcomes are better than the natural history of this disease.