Nonstenotic Carotid Plaques in Ischemic Stroke: Analysis of the STRATIS Registry

BACKGROUND AND PURPOSE

Few studies assess nonstenotic carotid plaques on CTA, and the causative role of these plaques in stroke is not entirely clear. We used CTA to determine the prevalence of nonstenotic carotid plaques (<50%), plaque features, and their association with ipsilateral strokes in patients with cardioembolic and cryptogenic strokes.

MATERIALS AND METHODS

Data were from the Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke (STRATIS) registry, a prospective, nonrandomized registry of patients undergoing thrombectomy with the Solitaire device. The prevalence of nonstenotic carotid plaques ipsilateral and contralateral to the stroke was compared in patients with cryptogenic and cardioembolic strokes. Plaque features were further compared within both subgroups between patients with and without ipsilateral stroke. Adjusted associations among nonstenotic carotid plaque, plaque characteristics, and ipsilateral stroke in both subgroups were determined with logistic regression.

RESULTS

Of the 946 patients in the data base, 226 patients with cardioembolic stroke (median age, 72 years) and 141 patients with cryptogenic stroke (median age, 69 years) were included in the analysis. The prevalence of nonstenotic carotid plaque in the cardioembolic and cryptogenic subgroups was 33/226 (14.6%) and 32/141 (22.7%), respectively. Bilateral nonstenotic carotid plaques were seen in 10/226 (4.4%) patients with cardioembolic and 13/141 (9.2%) with cryptogenic strokes. Nonstenotic carotid plaques were significantly associated with ipsilateral strokes in the cardioembolic stroke (adjusted OR = 1.91; 95% CI, 1.15-3.18) and the cryptogenic stroke (adjusted OR = 1.69; 95% CI, 1.05-2.73) groups. Plaque irregularity, hypodensity, and per-millimeter increase in plaque thickness were significantly associated with ipsilateral stroke in the cryptogenic subgroup.

CONCLUSIONS

Nonstenotic carotid plaques were significantly associated with ipsilateral stroke in cardioembolic and cryptogenic stroke groups, and there was an association of plaque irregularity and hypodense plaque with ipsilateral stroke in the cryptogenic group, suggesting these plaques could be a potential cause of stroke in these patient subgroups.

Intra-Arterial Thrombolysis after Unsuccessful Mechanical Thrombectomy in the STRATIS Registry

BACKGROUND AND PURPOSE

Recent data suggest that intra-arterial thrombolytics may be a safe rescue therapy for patients with acute ischemic stroke after unsuccessful mechanical thrombectomy; however, safety and efficacy remain unclear. Here, we evaluate the use of intra-arterial rtPA as a rescue therapy in the Systematic Evaluation of Patients Treated with Neurothrombectomy Devices for Acute Ischemic Stroke (STRATIS) registry.

MATERIALS AND METHODS

STRATIS was a prospective, multicenter, observational study of patients with acute ischemic stroke with large-vessel occlusions treated with the Solitaire stent retriever as the first-line therapy within 8 hours from symptom onset. Clinical and angiographic outcomes were compared in patients having rescue therapy treated with and without intra-arterial rtPA. Unsuccessful mechanical thrombectomy was defined as any use of rescue therapy.

RESULTS

A total of 212/984 (21.5%) patients received rescue therapy, of which 83 (39.2%) and 129 (60.8%) were in the no intra-arterial rtPA and intra-arterial rtPA groups, respectively. Most occlusions were M1, with 43.4% in the no intra-arterial rtPA group and 55.0% in the intra-arterial rtPA group (P = .12). The median intra-arterial rtPA dose was 4 mg (interquartile range = 2-12 mg). A trend toward higher rates of substantial reperfusion (modified TICI  ≥ 2b) (84.7% versus 73.0%, P = .08), good functional outcome (59.2% versus 46.6%, P = .10), and lower rates of mortality (13.3% versus 23.3%, P = .08) was seen in the intra-arterial rtPA cohort. Rates of symptomatic intracranial hemorrhage did not differ (0% versus 1.6%, P = .54).

CONCLUSIONS

Use of intra-arterial rtPA as a rescue therapy after unsuccessful mechanical thrombectomy was not associated with an increased risk of symptomatic intracranial hemorrhage or mortality. Randomized clinical trials are needed to understand the safety and efficacy of intra-arterial thrombolysis as a rescue therapy after mechanical thrombectomy.

Effect of Intracranial Atherosclerotic Disease on Endovascular Treatment for Patients with Acute Vertebrobasilar Occlusion

BACKGROUND AND PURPOSE

Although intracranial atherosclerotic disease is often encountered during endovascular treatment for acute vertebrobasilar occlusions, its clinical implication is not well-known. We aimed to evaluate whether intracranial atherosclerotic disease influences the clinical outcomes following endovascular treatment of acute vertebrobasilar occlusive stroke.

MATERIALS AND METHODS

Fifty-one patients with acute vertebrobasilar occlusive stroke were included. The onset-to-groin puncture time was ≤12 hours, and aspiration- or stent-based thrombectomy was used as the primary treatment method. Following primary endovascular treatment, intracranial atherosclerotic disease (IAD group) was angiographically diagnosed when a fixed focal stenosis was observed at the occlusion site, whereas embolism (embolic group) was diagnosed if no stenosis was observed. Clinical and treatment variables were compared in both groups, and IAD was evaluated as a prognostic factor for clinical outcomes.

RESULTS

The baseline NIHSS score tended to be lower (14 versus 22, P = .097) in the IAD group (n = 19) than in the embolic group (n = 32). The procedural time was longer in the IAD group (96 versus 61 minutes, P = .002), despite similar rates of TICI 2b-3 (89.5% versus 87.5%, P = 1.000). The NIHSS score at 7 days was higher (21 versus 8, P = .060) and poor outcomes (mRS 4-6 at 3 months) were more frequent in the IAD group (73.7% versus 43.8%, P = .038). IAD (odds ratio, 5.469; 95% CI, 1.09-27.58; P = .040) was independently associated with poor outcomes.

CONCLUSIONS

An arterial occlusion related to IAD was associated with a longer procedural time and poorer clinical outcome. Further studies are warranted to elucidate the appropriate endovascular strategy.

Abstract WMP8: Results of Trevo Acute Ischemic Stroke Thrombectomy Registry: Predictors of Clinical Outcome

Background and Purpose: Recent randomized clinical trial (RCTs) demonstrated efficacy of mechanical thrombectomy using stent-retrievers in acute ischemic stroke (AIS) patients. The main purpose of TRevo ACute Ischemic StroKe (TRACK) stent-retriever thrombectomy multicenter registry is to demonstrate safety and efficacy in real life clinical practice.

Methods: The investigator-initiated TRACK multicenter registry recruited 24 sites in north America to submit demographic, clinical, site-adjudicated angiographic, and outcome data on consecutive AIS patients treated with Trevo stent-retriever device as the first treatment option. Standard clinical safety (symptomatic intracranial hemorrhage (sICH), and mortality) and efficacy (revascularization and disability) outcomes and predictors of clinical outcome were analyzed.

Results: 624 patients were enrolled in the TRACK registry. Median age was 68 years (range 16-94, 118 (18.1%) >80), male gender was 51.4%, and 67.7% were white. The median National Institutes of Health Stroke Severity Scale (NIHSS) was 17 (IQR 13-22). Transfer cases were 50.6% with IV-rtPA use in 318 cases (51.3%). Median onset to groin puncture (OTG) time was 283 min (IQR 198.5-443), and groin puncture to revascularization was 66 min (IQR 37.5-103). Anterior circulation occlusion was 86.2% (MCA/M2 in 55.2% followed by ICA in 15.9% and M2 in 12.7%). Use of GA was in 389 cases (62.3%), number of passes were ≤ 3 in 92% of the cases (1: 45.2%, 2:28%, and 3:18.7%), 291 (46.7%) had BGC use. Rescue use was seen in 21.7%. Revascularization of ≥ TIMI 2 was 81.8% and ≥ TICI 2b was 70%. The primary outcome of mRS of ≥ 2 was 48.3% in the full cohort, and 50.6% in TREVO-2 like group. sICH and mortality were 7.2%, and 20.1% in the full cohort vs 6.9% and 17.5% in the TREVO-2 like group, respectively. The independent predictors of clinical outcome were lower baseline NIHSS, younger age, use of BGC, successful recanalization, and no general anesthesia (GA).

Conclusions: The real life clinical practice Trevo registry demonstrated good clinical outcome and high rate of recanalization. Younger age, lower baseline NIHSS, use of balloon guide catheter, successful recanalization, and avoiding endotrachaeal GA independent predictors of good clinical outcome.

Mechanical Thrombectomy for Isolated M2 Occlusions: A Post Hoc Analysis of the STAR, SWIFT, and SWIFT PRIME Studies

BACKGROUND AND PURPOSE

Mechanical thrombectomy is beneficial for patients with acute ischemic stroke and a proximal anterior occlusion, but it is unclear if these results can be extrapolated to patients with an M2 occlusion. The purpose of this study was to examine the technical aspects, safety, and outcomes of mechanical thrombectomy with a stent retriever in patients with an isolated M2 occlusion who were included in 3 large multicenter prospective studies.

MATERIALS AND METHODS

We included patients from the Solitaire Flow Restoration Thrombectomy for Acute Revascularization (STAR), Solitaire With the Intention For Thrombectomy (SWIFT), and Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT PRIME) studies, 3 large multicenter prospective studies on thrombectomy for ischemic stroke. We compared outcomes and technical details of patients with an M2 with those with an M1 occlusion. All patients were treated with a stent retriever. Imaging data and outcomes were scored by an independent core laboratory. Successful reperfusion was defined as modified Thrombolysis in Cerebral Infarction score of 2b/3.

RESULTS

We included 50 patients with an M2 and 249 patients with an M1 occlusion. Patients with an M2 occlusion were older (mean age, 71 versus 67 years; P = .04) and had a lower NIHSS score (median, 13 versus 17; P < .001) compared with those with an M1 occlusion. Procedural time was nonsignificantly shorter in patients with an M2 occlusion (median, 29 versus 35 minutes; P = .41). The average number of passes with a stent retriever was also nonsignificantly lower in patients with an M2 occlusion (mean, 1.4 versus 1.7; P = .07). There were no significant differences in successful reperfusion (85% versus 82%, P = .82), symptomatic intracerebral hemorrhages (2% versus 2%, P = 1.0), device-related serious adverse events (6% versus 4%, P = .46), or modified Rankin Scale score 0-2 at follow-up (60% versus 56%, P = .64).

CONCLUSIONS

Endovascular reperfusion therapy appears to be feasible in selected patients with ischemic stroke and an M2 occlusion.

Revascularization grading in endovascular acute ischemic stroke therapy

BACKGROUND

Recanalization and angiographic reperfusion are key elements to successful endovascular and interventional acute ischemic stroke (AIS) therapy. Intravenous recombinant tissue plasminogen activator (rt-PA), the only established revascularization therapy approved by the US Food & Drug Administration for AIS, may be less effective for large artery occlusion. Thus, there is enthusiasm for endovascular revascularization therapies, which likely provide higher recanalization rates, and trials are ongoing to determine clinical efficacy and compare various methods. It is anticipated that clinical efficacy will be well correlated with revascularization of viable tissue in a timely manner.

METHOD

Reporting, interpretation, and comparison of the various revascularization grading methods require agreement on measurement criteria, reproducibility, ease of use, and correlation with clinical outcome. These parameters were reviewed by performing a Medline literature search from 1965 to 2011. This review critically evaluates current revascularization grading systems.

RESULTS AND CONCLUSION

The most commonly used revascularization grading methods in AIS interventional therapy trials are the thrombolysis in cerebral ischemia (TICI, pronounced "tissy") and thrombolysis in myocardial ischemia (TIMI) scores. Until further technical and imaging advances can incorporate real-time reliable perfusion studies in the angio-suite to delineate regional perfusion more accurately, the TICI grading system is the best defined and most widely used scheme. Other grading systems may be used for research and correlation purposes. A new scale that combines primary site occlusion, lesion location, and perfusion should be explored in the future.

SOLITAIRE™ with the intention for thrombectomy (SWIFT) trial: design of a randomized, controlled, multicenter study comparing the SOLITAIRE™ Flow Restoration device and the MERCI Retriever in acute ischaemic stroke

RATIONALE

Self-expanding stent retrievers are a promising new device class designed for rapid flow restoration in acute cerebral ischaemia. The SOLITAIRE™ Flow Restoration device (SOLITAIRE) has shown high rates of recanalization in preclinical models and in uncontrolled clinical series.

AIMS

(1) To demonstrate non-inferiority of SOLITAIRE compared with a legally marketed device, the MERCI Retrieval System®; (2) To demonstrate safety, feasibility, and efficacy of SOLITAIRE in subjects requiring mechanical thrombectomy diagnosed with acute ischaemic stroke. DESIGN : Multicenter, randomized, prospective, controlled trial with blinded primary end-point ascertainment.

STUDY PROCEDURES

Key entry criteria include: age 22-85; National Institute of Health Stroke Scale (NIHSS) ≥8 and <30; clinical and imaging findings consistent with acute ischaemic stroke; patient ineligible or failed intravenous tissue plasminogen activator; accessible occlusion in M1 or M2 middle cerebral artery, internal carotid artery, basilar artery, or vertebral artery; and patient able to be treated within 8 h of onset. Sites first participate in a roll-in phase, treating two patients with the SOLITAIRE device, before proceeding to the randomized phase. In patients unresponsive to the initially assigned therapy, after the angiographic component of the primary end-point is ascertained (reperfusion with the initial assigned device), rescue therapy with other reperfusion techniques is permitted.

OUTCOMES

The primary efficacy end-point is successful recanalization with the assigned study device (no use of rescue therapy) and with no symptomatic intracranial haemorrhage. Successful recanalization is defined as achieving Thrombolysis In Myocardial Ischemia 2 or 3 flow in all treatable vessels. The primary safety end-point is the incidence of device-related and procedure-related serious adverse events. A major secondary efficacy end-point is time to achieve initial recanalization. Additional secondary end-points include clinical outcomes at 90 days and radiologic haemorrhagic transformation.

The neurocritical care research network: NCRN

Neurocritical care diseases carry a high morbidity and mortality. Therapeutic and technological advances in neurocritical care have greatly improved the outcome of a variety of life-threatening disorders including traumatic brain injury, acute ischemic stroke, intracerebral and subarachnoid hemorrhage, and anoxic injury following cardiac arrest. These advances have stemmed from a better understanding of the physiology of neurocritical care illnesses, improved neuromonitoring techniques, and the introduction of more efficacious treatments. Despite all the advances in neuromonitoring, diagnostic imaging, and emerging treatments, much research needs to be undertaken in neurocritical care. Many of the clinical trials carried out in the general critical care population have excluded neurocritical care patients. For instance, the landmark ARDSNET trial that demonstrated the beneficial effects of low tidal volume ventilation in patients with ARDS cannot be directly applied to neurocritical care patients who frequently may experience this pulmonary complication. There is a need for a more cohesive and integrated research system or network to establish a track record for high-quality, investigator-initiated clinical research in neurocritical care. Such a system may help us overcome potential impediments to the future advancement of neurocritical care research. We propose the creation of the neurocritical care research network. The mission of the Network is to facilitate multicenter and multidisciplinary collaboration and patient enrollment in clinical trials of specific neurocritical care diseases.

Research priorities in neurocritical care

This summary of the last session of the First Neurocritical Care Research Conference reviews the discussions about research priorities in neurocritical care. The first presentation reviewed current projects funded by the National Institute of Neurological Disorders and Stroke at the National Institutes of Health and potential models to follow including an independent Neurocritical Care Network or the creation of such a network with the goal of collaborating with already existing ones. Experienced neurointensivists then presented their views on the most common and important research questions that need to be answered and investigated in the field. Finally, utility of clinical registries was discussed emphasizing their importance as hypothesis generators. During the group discussion, interests in comparative effectiveness research, the use of physiological endpoints from monitoring and alternate trial design were expressed.

Research and technology in neurocritical care

The daily practice of neurointensivists focuses on the recognition of subtle changes in the neurological examination, interactions between the brain and systemic derangements, and brain physiology. Common alterations such as fever, hyperglycemia, and hypotension have different consequences in patients with brain insults compared with patients of general medical illness. Various technologies have become available or are currently being developed. The session on "research and technology" of the first neurocritical care research conference held in Houston in September of 2009 was devoted to the discussion of the current status, and the research role of state-of-the art technologies in neurocritical patients including multi-modality neuromonitoring, biomarkers, neuroimaging, and "omics" research (proteomix, genomics, and metabolomics). We have summarized the topics discussed in this session. We have provided a brief overview of the current status of these technologies, and put forward recommendations for future research applications in the field of neurocritical care.

Abstract 3554: GP IIb/IIIa Inhibitor Use during Endovascular Coil Embolization: A Single Center Experience

Introduction: Acute thromboembolic event (TEE) remains a considerable complication of endovascular aneurysm treatment. We sought to evaluate the safety of Glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors for TEE during endovascular aneurysm embolization (EAE).

Method: We reviewed a single-center retrospectively collected database of EAE from 7 / 2005 to 12/2010. All patients who received a GPIIb/IIIa inhibitor (abciximab or eptifibatide) were included in the analysis. Clinical, demographic, and radiographic data were retrospectively collected through chart review. TEE was defined as a partial or complete occlusion of the parent vessel at the aneurysm neck, and/or distal vessel within the parent vessel territory. Recanalization was defined as near-complete or complete resolution of vessel thrombus on angiogram. New intracerebral hemorrhage (ICH) was defined as new intraparenchymal hemorrhage finding on head CT or new area of subarachnoid hemorrhage (SAH) >1mm in thickness.

Result: Among a database of 701 cases, a GPIIb/IIIa inhibitor was used in a total of 61 (8.7%) cases, of these 57 were treated for TEE and 4 were treated prophylactically for sub therapeutic platelet point of care testing. There were 41 males, and the mean age was 54 ±13 years. The TEE occurred slightly higher during ruptured aneurysm coiling (57% and 43%, p=0.07). Thirty-nine (64%) cases were treated with adjunctive devices, which included a stent (29) or balloon (10), p-value=0.001. Close to half of the TEE was not occlusive (54%). A total of 55 (90%) cases received abciximab with a mean bodyweight base dose of 0.17mg/kg, and 6 (10%) cases received eptifibatide with a mean body weight base dose of 0.15mg/kg. Nine (16%) cases required additional therapy for ongoing clot (stent (3), balloon (3), penumbra (1), intra- arterial thrombolysis (1), and vessel sacrifice (1). Forty-two (74%) cases had complete angiographic recanalization (77% using abciximab and 25% using eptifibatide, (p=0.051)). There were 10 (16%) new ICH; 3 (5%) which were symptomatic. Patients with new ICH had non significant higher mean bodyweight dose compare to patients without new ICH 0.26 0.32 mg/kg and 0.15 0.07 mg/kg respectively.

Conclusion: GP IIb/IIIa inhibitor use in EAE as single and multimodal therapy for acute TEE may have acceptable safety and recanalization rates (symptomatic ICH of 5% and complete recanalization of 74%). Further study to confirm the current study findings and identify optimal dosing is needed; however these data suggest that a lower dose may be favorable.

Measurement of antiplatelet inhibition during neurointerventional procedures: the effect of antithrombotic duration and loading dose

BACKGROUND/OBJECTIVE

Symptomatic thromboembolic events are the most common complications associated with aneurysm coiling, and carotid and intracranial stenting. Our objective is to assess the effect of aspirin (ASA) and clopidogrel dose and duration on platelet inhibition using a point of care assay in neurointerventional (NI) suite.

METHOD

The dose, duration, and point of care platelet function assay data for clopidogrel and aspirin therapy were prospectively collected between February 2006 and November 2007. Inadequate platelet inhibition for ASA was defined as >or=550 ASA reaction units (ARU), and for clopidogrel was defined as <or=50% inhibition of the P2Y12/ADP receptor

RESULTS

We collected data from 216 consecutive patients. Inadequate platelet inhibition was noted in 13% of patients on aspirin and 66% of patients on clopidogrel (P-value < .0001). Patients taking clopidogrel 75 mg for >or=7 days, 300 mg for 24 hours, and 600 mg same day load had a mean P2Y12/ADP inhibition of 45%, 35% (P-value = .09), and 16%, respectively (P-value = .005).

CONCLUSION

Premedication with clopidogrel, in contrast to aspirin, does not achieve adequate platelet inhibition in about two-third of the patients. Same day antiplatelet loading may be insufficient to achieve adequate platelet inhibition and should be avoided if clinically feasible.

Performance and training standards for endovascular ischemic stroke treatment

Stroke is the third leading cause of death in the USA, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750,000 new strokes that occur each year, resulting in 200,000 deaths, or 1 of every 16 deaths, per year in the USA alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in two randomized trials and numerous case series. Although two devices have been granted FDA approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies which historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. The participating member organizations of the Neurovascular Coalition involved in the writing and endorsement of this document are the Society of NeuroInterventional Surgery, the American Academy of Neurology, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Cerebrovascular Section, and the Society of Vascular & Interventional Neurology.

Using a distal access catheter in acute stroke intervention with penumbra, merci and gateway. A technical case report

SUMMARY

This technical report describes the successful use of the newly introduced Distal Access Catheter, initially designed to work with the Merci Retrieval System with the Penumbra aspiration system as the main aspiration catheter. Both devices, one a clot retriever and the other a thrombo-aspiration device, can be used and deployed via the same catheter saving time during acute stoke intervention. Moreover, the larger inner diameter of the distal access catheter may allow more effective clot aspiration.

The use of a covered stent graft for obliteration of high-flow carotid cavernous fistula presenting with life-threatening epistaxis

BACKGROUND

We present a rare complication of trans-sphenoidal adenectomy (TSA) for pituitary macroadenoma: carotid cavernous fistula (CCF) that was treated with endovascular therapy. The incidence of internal carotid artery (ICA) injury following TSA is 1% and may spontaneously heal by packing and rarely manifest as symptomatic CCF/aneurysm. Treatment of post-TSA CCF may be challenging due to the breach of nasal floor and may be prone to recurrence.

PRESENTATION/INTERVENTION

Uncontrolled intra-operative bleeding during a TSA led to an emergent angiogram to show slow-flow left CCF. Due to clinical deterioration with nasal bleeding, angiography was repeated after 4 h; the fistula had transformed into high flow with significant increase in size, and was therefore embolized using stent-assisted coiling. The fistula recanalized in a month with massive epistaxis and was re-treated using a covered stent graft.

CONCLUSION

This case represents several unique learning points: (1) CCF as a complication of TSA due to close anatomical proximity; (2) the role of endovascular management post-TSA complication; (3) stent-assisted coil embolization of high-flow fistula with moderate ICA laceration; (4) recanalization of CCF causing massive epistaxis; (5) rare use of covered stent graft stent in distal intracranial circulation maintaining integrity and patency of ICA; (6) long-term results after covered stent graft with no in-stent restenosis.

Risk factors associated with major cerebrovascular complications after intracranial stenting

BACKGROUND

There are limited data on the relationship between patient and site characteristics and clinical outcomes after intracranial stenting.

METHODS

We performed a multivariable analysis that correlated patient and site characteristics with the occurrence of the primary endpoint (any stroke or death within 30 days of stenting or stroke in the territory of the stented artery beyond 30 days) in 160 patients enrolled in this stenting registry. All patients presented with an ischemic stroke, TIA, or other cerebral ischemic event (e.g., vertebrobasilar insufficiency) in the territory of a suspected 50-99% stenosis of a major intracranial artery while on antithrombotic therapy.

RESULTS

Cerebral angiography confirmed that 99% (158/160) of patients had a 50-99% stenosis. In multivariable analysis, the primary endpoint was associated with posterior circulation stenosis (vs anterior circulation) (hazard ratio [HR] 3.4, 95% confidence interval [CI] 1.2-9.3, p = 0.018), stenting at low enrollment sites (< 10 patients each) (vs high enrollment site) (HR 2.8, 95% CI 1.1-7.6, p = 0.038), < or = 10 days from qualifying event to stenting (vs > or = 10 days) (HR 2.7, 95% CI 1.0-7.8, p = 0.058), and stroke as a qualifying event (vs TIA/other) (HR 3.2, 95% CI 0.9-11.2, p = 0.064). There was no significant difference in the primary endpoint based on age, gender, race, or percent stenosis (50-69% vs 70-99%).

CONCLUSIONS

Major cerebrovascular complications after intracranial stenting may be associated with posterior circulation stenosis, low volume sites, stenting soon after a qualifying event, and stroke as the qualifying event. These factors will need to be monitored in future trials of intracranial stenting.

Magnetic resonance imaging results can affect therapy decisions in hyperacute stroke care

BACKGROUND

Despite some limitations, a perfusion/diffusion mismatch can provide a working estimate of the ischemic penumbra in hyperacute stroke and has successfully been used to triage patients.

PURPOSE

To evaluate whether the addition of magnetic resonance imaging (MRI) to clinical and non-contrast computed tomography (CT) data alters diagnosis and choice of therapy.

MATERIAL AND METHODS

We retrospectively analyzed clinical records, and CT and MRI data fully available in 97 of 117 patients. Upon clinical examination and CT, a diagnosis and treatment path was scored and compared to treatment path after addition of MRI data. The MRI protocol included T2-weighted images, diffusion-weighted images (DWI), and perfusion-weighted images (PWI), and MR angiography (MRA).

RESULTS

MRI data were acquired in less than 15 min. In 20 of 97 patients (21%), the diagnosis changed after MRI. In 25 of 97 patients (26%), the presumptive treatment plan was changed after MRI evaluation. Thirteen patients had their treatment changed from thrombolytic to nonthrombolytic therapy. Three patients were changed from nonthrombolytic to intraarterial (IA) thrombolysis. In one patient, treatment was changed from intravenous (IV) to IA thrombolysis, and in five patients it was changed from IA to IV thrombolysis. In two patients, systemic heparin was added to antiplatelet therapy.

CONCLUSION

The expansion of the acute stroke protocol to include MRI altered the therapy plan in 26% of our patients. The utility of MRI, shown here to improve patient stratification into best-treatment options, demonstrates the value of using MRI to optimize care in hyperacute stroke patients.

The NIH registry on use of the Wingspan stent for symptomatic 70-99% intracranial arterial stenosis

BACKGROUND

The Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial showed that patients with symptomatic 70% to 99% intracranial arterial stenosis are at particularly high risk of ipsilateral stroke on medical therapy: 18% at 1 year (95% CI = 3% to 24%). The Wingspan intracranial stent is another therapeutic option but there are limited data on the technical success of stenting and outcome of patients with 70% to 99% stenosis treated with a Wingspan stent.

METHODS

Sixteen medical centers enrolled consecutive patients treated with a Wingspan stent in this registry between November 2005 and October 2006. Data on stenting indication, severity of stenosis, technical success (stent placement across the target lesion with <50% residual stenosis), follow-up angiography, and outcome were collected.

RESULTS

A total of 129 patients with symptomatic 70% to 99% intracranial stenosis were enrolled. The technical success rate was 96.7%. The mean pre and post-stent stenoses were 82% and 20%. The frequency of any stroke, intracerebral hemorrhage, or death within 30 days or ipsilateral stroke beyond 30 days was 14.0% at 6 months (95% CI = 8.7% to 22.1%). The frequency of >or=50% restenosis on follow-up angiography was 13/52 (25%).

CONCLUSION

The use of a Wingspan stent in patients with severe intracranial stenosis is relatively safe with high rate of technical success with moderately high rate of restenosis. Comparison of the event rates in high-risk patients in Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) vs this registry do not rule out either that stenting could be associated with a substantial relative risk reduction (e.g., 50%) or has no advantage compared with medical therapy. A randomized trial comparing stenting with medical therapy is needed.

Acute motor-sensory axonal neuropathy associated with active systemic lupus erythematosus and anticardiolipin antibodies

Acute motor-sensory axonal neuropathy (AMSAN) is an axonal variant of Guillian-Barré syndrome (GBS) that presents with acute ascending quadriparesis. This has generally been described in association with Campylobacter jejuni infections or with anti-ganglioside antibodies. Known cases have shown a slow recovery and a poor prognosis. We report a case with clinical and electrophysiological evidence of AMSAN in association with active systemic lupus erythematosus (SLE) and anticardiolipin antibodies but not the other associations, with a rapid response to combination immunosuppressant and intravenous immunoglobulin (IVIg) therapy. The association between AMSAN and SLE has not been previously described. This case illustrates that early recognition and the utilization of electrophysiologic techniques may be beneficial in the diagnosis and management of GBS associated with SLE. Fulminant or rapidly progressive cases should be managed in specialized intensive care units. Combination therapy of immunosuppressants and IVIg may be beneficial in non-vasculitic axonal radiculo-neuropathies associated with SLE, resulting in good outcomes.

Vertebrobasilar dolichoectasia diagnosed by magnetic resonance angiography and risk of stroke and death: a cohort study

OBJECTIVE

There are only limited epidemiological studies evaluating the association between vertebrobasilar dolichoectasia (VBD) and outcomes. This study was designed to elucidate the outcome and prognosis of adults diagnosed with VBD by magnetic resonance angiography (MRA) and to ascertain if these outcomes were independent of known vascular risk factors.

METHODS

A cohort study was designed to compare VBD cases identified retrospectively from a computerised database of MRA reports with age and sex matched controls evaluated after a 4-7 year period, and 1440 MRA reports were reviewed. The inclusion criteria were age > or =18 years and a radiological diagnosis of VBD. Patients were excluded if there was haemodynamically significant stenosis or occlusion of the posterior circulation. Data were obtained by medical record review and telephone questionnaires. The primary outcome measure was transient or fixed posterior circulation dysfunction (PCD), with a secondary outcome measure of all cause mortality.

RESULTS

Sixty four VBD cases were obtained, and 19 cases (30%) were excluded due to refusal and/or insufficient follow up data. From the same computerised database, 45 controls were selected by consecutive sampling. The mean age at follow up was 73.4 years for VBD cases and 73.1 years for controls, with a median follow up period of 64 months. VBD was associated with fixed/transient PCD (p = 0.0001; estimated adjusted odds ratio (OR) of 20.6 and confidence interval (CI) of 4.4 to 95.3), and with all cause mortality (OR = 3.6 CI 1.3 to 10.3); (p = 0.018). VBD cases had 36% mortality, with 50% occurring within 34 months of the initial diagnosis. The VBD cumulative survival curve was statistically different from the controls (p = 0.012 by Mantel-Cox log rank test).

CONCLUSIONS

This study suggests that VBD may be an independent risk factor for stroke. VBD cases had an increased likelihood for PCD, all cause mortality, and reduced cumulative survival independent of other vascular risk factors in this cohort. Larger population based prospective studies are required to verify these results.

Asymptomatic middle cerebral artery stenosis diagnosed by magnetic resonance angiography

We reviewed 1440 MRA studies to identify patients with middle cerebral artery stenosis (MCAS). We identified 99 cases, and after reviewing the clinical records, classified 28 as asymptomatic MCAS (AMCAS), a prevalence of 2%. Suspected stroke was the most frequent indication for MRA. Follow-up was available for 21, mean 46.7 months (range 2.4-75.6 months). One stroke occurred in the AMCAS territory (5%), other strokes in five patients (24%). There were five deaths in patients with MCAS; age > 69 (P = 0.045) was the only associated risk factor. This study suggests that patients in whom MRA is performed and shows AMCAS may be at increased risk of strokes in any vascular distribution or of death.

Thrombolytic therapy for acute extra-cranial artery dissection: report of two cases

Extra-cranial arterial dissection accounts for 10% of strokes in young people. Information on safety of thrombolytic administration in this group is limited. The literature, however, does not favor use of thrombolytics for myocardial ischemia when peripheral arterial dissection coexists. Based on the clinical and radiological features, two patients who presented with acute stroke secondary to arterial dissection were considered for thrombolysis. One of them received intra-venous recombinant tissue plasminogen activator (rtPA), and the other patient received intra-arterial rtPA. There were no post thrombolysis complications. This report supports feasibility of administering thrombolytics in acute ischemic strokes resulting from extra-cranial arterial dissection. Future larger studies are necessary to determine the efficacy, safety and long-term outcome in this patient population.

Benefits of perfusion MR imaging relative to diffusion MR imaging in the diagnosis and treatment of hyperacute stroke

BACKGROUND AND PURPOSE

The development of thrombolytic agents for use with compromised cerebral blood flow has made it critical to quickly identify those patients to best treat. We hypothesized that combined diffusion and perfusion MR imaging adds vital diagnostic value for patients for whom the greatest potential benefits exist and far exceeds the diagnostic value of diffusion MR imaging alone.

METHODS

The cases of patients with neurologic symptoms of acute ischemic stroke who underwent ultra-fast emergent MR imaging within 6 hours were reviewed. In all cases, automatic processing yielded isotropic diffusion images and perfusion time-to-peak maps. Images with large vessel distribution ischemia and with mismatched perfusion abnormalities were correlated with patient records. All follow-up images were reviewed and compared with outcomes resulting from hyperacute therapies.

RESULTS

For 16 (26%) of 62 patients, hypoperfusion was the best MR imaging evidence of disease distribution, and for 15 of the 16, hypoperfusion (not abnormal diffusion) comprised the only imaging evidence for disease involving large vessels. For seven patients, diffusion imaging findings were entirely normal, and for nine, diffusion imaging delineated abnormal signal in either small vessel distributions or in a notably smaller cortical branch in one case. In all cases, perfusion maps were predictive of eventual lesions, as confirmed by angiography, CT, or subsequent MR imaging.

CONCLUSION

If only diffusion MR imaging is used in assessing patients with hyperacute stroke, nearly one quarter of the cases may be incorrectly categorized with respect to the distribution of ischemic at-risk tissue. Addition of perfusion information further enables better categorizing of vascular distribution to allow the best selection among therapeutic options and to improve patient outcomes.

Vertebral artery dissection with amphetamine abuse

Vertebral artery dissection is an important cause of disabling stroke in young adults, recognition of its presenting features and risk factors is paramount for expeditious diagnosis and preventive treatment. Numerous risk factors for vertebral artery dissection have been reported; trauma is the most common. This case report describes a patient with amphetamine abuse, who had posterior circulation stroke from vertebral artery dissection and artery to artery embolization. Literature is reviewed and clinical relevance is discussed.

Neuromuscular transmission defect caused by carbamazepine

The clinical effect of carbamazepine (CBZ) on neuromuscular transmission is described in two children who presented in coma with diffuse hypotonia and areflexia following CBZ overdose. Repetitive nerve stimulation (RNS) showed a decremental response only at high-frequency stimulation. With supportive care, the patients made an uneventful recovery. Follow-up RNS was normal. This is the first report of a clinically evident neuromuscular transmission defect produced by CBZ. We postulate that CBZ's known effect on decreasing sodium channel depolarization produced a defect in neuromuscular transmission. The report emphasizes the contribution of RNS in the evaluation of coma of uncertain etiology, particularly in cases of possible intoxication, and the potential for CBZ to compromise neuromuscular transmission in normal individuals or in patients with a decreased neuromuscular transmission safety factor.

Pendular nystagmus in patients with peroxisomal assembly disorder

BACKGROUND

Pendular nystagmus commonly occurs in congenital and acquired disorders of myelin.

OBJECTIVE

To characterize the nystagmus in 3 siblings with an infantile form of an autosomal recessive peroxisomal assembly disorder causing leukodystrophy.

DESIGN

We examined visual function and measured eye movements using infrared oculography. We noted changes in eye speed and frequency before and after the administration of gabapentin to 1 patient.

RESULTS

All 3 siblings showed optic atrophy and pendular nystagmus that was predominantly horizontal, at a frequency of 3 to 6 Hz, with phase shifts of 45 degrees to 80 degrees between the oscillations of each eye. Gabapentin administered to 1 child caused a modest improvement of vision and the reduction of the velocity and frequency of oscillations in the eye with worse nystagmus.

CONCLUSION

The pendular nystagmus in these patients was due to their leukodystrophy and may have a similar pathogenesis to the oscillations seen in other disorders affecting central myelin.