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L Nelson Hopkins

Publications and source records attributed to L Nelson Hopkins.

At least 19 recordsLinked to original sources
PubMed2007

The CAPTURE registry: results of carotid stenting with embolic protection in the post approval setting.

BACKGROUND: Pivotal study data examining carotid stenting with embolic protection as a less invasive alternative to endarterectomy for high surgical risk patients have been acquired under controlled conditions with highly selected physicians and hospitals. This report examines outcomes of carotid stenting post-approval after diffusion of this technology to a broader cross-section of physicians and hospitals. METHODS: The Carotid Acculink/Accunet Post-Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) is a prospective, multi-center registry to assess two important aspects of the post-IDE experience: the safety of carotid stenting by physicians with varying levels of experience as a measure of the adequacy of physician training, and the identification of rare/unexpected device-related complications. The primary endpoint was a composite of death, any stroke, or myocardial infarction within 30 days post-procedure. RESULTS: 3,500 patients were enrolled by 353 physicians at 144 sites. The 30-day primary endpoint event rate was 6.3% (95% CI: 5.5-7.1%) and did not differ among the three operator experience levels (5.3%, 6.0%, and 7.4%; P = 0.31) from most to least experienced, respectively. There were no differences in outcomes among physician specialties when adjusted for case mix. There were no unanticipated device related adverse events. CONCLUSIONS: The results of the CAPTURE study compare favorably to those achieved in the predicate pivotal investigations, and suggest that the post-approval transfer of this new therapy to the community practice setting via carotid stent training programs is effective in preparing physicians with varying experience levels and specialty training backgrounds.

Aged↗
PubMed2006

Reversal of a 30-h fixed deficit with carotid angioplasty and stenting: technical note.

We describe the case of an 82-year-old man with a fixed neurological deficit of 30 h duration. A left hemispheric perfusion deficit was found on perfusion/diffusion imaging studies in conjunction with an ipsilateral carotid stenosis documented by cerebral angiography. Carotid angioplasty with stent placement was performed and resulted in dramatic clinical improvement. Carotid stenosis can cause acute hemodynamic hypoperfusion with a symptomatic reversible clinical deficit.

Aged, 80 and over↗
PubMed2006

Carotid stenting with distal protection in high surgical risk patients: the BEACH trial 30 day results.

BACKGROUND: The BEACH trial evaluated the outcomes of carotid artery stent placement with distal emboli protection, using the Carotid Wallstent and the FilterWire EX/EZ(TM), in patients at high surgical risk for carotid endarterectomy (CEA). METHODS: We enrolled 747 patients at high surgical risk for CEA due to prespecified anatomical criteria and/or medical comorbidities. The trial included both symptomatic (>50% carotid artery stenosis) as well as asymptomatic (>80% carotid artery stenosis) high surgical risk patients. Three groups of patients were included in the trial. The Roll-in (R) group (n = 189/747, [25%]) included up to nine patients per site for familiarization of the device and protocol; the Pivotal (P) group (n = 480/747, [65%]) was intended for presentation to the FDA for consideration of device approval; and a Bilateral (B) registry group (n = 78/747, [10%]) was included because of the need to treat patients with bilateral carotid artery disease. In the 480 Pivotal patients, anatomic criteria represented the most frequent high-risk surgical category for enrollment (58.8%), followed by prior CEA (34.2%), multivessel (>or=2) coronary artery disease (21.7%), and contralateral carotid occlusion (18.1%). RESULTS: The technical success rate for stent deployment and FilterWire EX/EZ deployment and retrieval was 98.2%. The mean postprocedure angiographic diameter stenosis in the Pivotal group was reduced to 10.8%, while the overall procedure success rate (<50% residual diameter stenosis) after stent deployment was 98%. The 30 day composite major adverse event (MAE) rate for the entire cohort of 747 patients (i.e. inclusive of all 3 groups) was 5.8% (all death = 1.5%, all stroke = 4.4%, and all myocardial infarction (MI) = 1.0%). In subgroup analysis, there was no significant difference in the MAE rate between the three groups (P = 5.8%, R = 6.9%, B = 2.6%, P = 0.42). CONCLUSION: The similarity in periprocedural event rates for the Pivotal and Roll-in groups suggests a flat learning curve for experienced operators using this carotid stent system. The similarity in event rates for the Bilateral group, when compared with the Roll-in and Pivotal groups, suggests that staged sequential treatment of bilateral stenoses may be performed at the same risk as for unilateral lesions. The 30-day safety of this stent and distal emboli protection system is encouraging and compares favorably with other carotid stent trials in high surgical risk patients.

Aged↗
PubMed2006

Intravascular ultrasound identification of intraluminal embolic plaque material during carotid angioplasty with stenting.

INTRODUCTION: Carotid angioplasty with stenting (CAS) has evolved as a viable method for treating patients at high risk for carotid endarterectomy. Strokes complicating CAS are most commonly caused by the liberation and distal embolization of embolic material from plaque during the procedure. METHODS: CAS with distal embolic protection (DEP) was performed using the assistance of intravascular ultrasound (IVUS) in a 68-year-old man with asymptomatic carotid artery stenosis. Evaluation of the plaque pretreatment was performed using virtual histology software. IVUS evaluation was also performed after prestent angioplasty, stenting, and poststent angioplasty. RESULTS: Initial degree of angiographic stenosis was 78.9%. Final degree of stenosis was 15.7%. By IVUS, stenosis by minimum lumen diameter and minimum lumen area were 75.6% and 93.4% pretreatment, respectively, and 42.2% and 47.1% posttreatment, respectively. An intraluminal lesion was noted in the distal aspect of the stent after poststent angioplasty but before DEP device removal. Ultrasonographic characteristics of the intraluminal defect were consistent with ruptured plaque material. Angiographic runs failed to demonstrate the lesion. A repeat IVUS run performed approximately 10 min later failed to depict the lesion, suggesting that distal embolization had occurred. Embolic material was noticed in the DEP device after removal. The patient did not experience any ischemic neurological symptoms. CONCLUSIONS: IVUS can identify intraluminal plaque material, which may be a precursor for embolism and delayed ischemic events after CAS. IVUS may allow for treatment before distal embolization of plaque material. Virtual histology IVUS software may help to identify carotid lesions at higher risk for significant embolization during CAS.

Aged↗
PubMed2006

Protected carotid stenting in high-surgical-risk patients: the ARCHeR results.

BACKGROUND: Carotid endarterectomy is the standard of care for most patients with severe extracranial carotid bifurcation disease. However, its safety and efficacy in patients with significant surgical risk are unclear. The ARCHeR (ACCULINK for Revascularization of Carotids in High-Risk patients) trial was performed to determine whether carotid artery stenting with embolic protection is a safe and effective alternative to endarterectomy in high-surgical-risk patients. METHODS: The ARCHeR trial is a series of three sequential, multicenter, nonrandomized, prospective studies. Forty-eight sites enrolled 581 high-surgical-risk patients between May 2000 and September 2003. Patients with severe carotid artery stenosis (angiographically defined, symptomatic > or =50%, or asymptomatic > or =80%) had an ACCULINK nitinol stent implanted. The ACCUNET filter embolic protection system was added to the procedure in the final 2 studies (422 patients). The primary efficacy end point was a composite of periprocedural (< or =30 days) death, stroke, and myocardial infarction, plus ipsilateral stroke between days 31 and 365. RESULTS: The 30-day rate of death/stroke/myocardial infarction was 8.3% (95% confidence interval [CI], 6.2%-10.8%), and that of stroke/death was 6.9% (95% CI, 5.0%-9.3%). Most (23/32) strokes were minor, of which more than half (12/23) returned to baseline National Institutes of Health Stroke Scale scores within 30 days. The 30-day major/fatal stroke rate was 1.5% (95% CI, 0.7%-2.9%). No hemorrhagic strokes were observed in the study. Ipsilateral cerebrovascular accident occurred in 1.3% between 30 days and 1 year, thus giving a primary composite end point of 30-day death/stroke/myocardial infarction plus ipsilateral stroke at 1 year of 9.6% (95% CI, 7.2%-12.0%), which is below the 14.4% historical control comparator. Target lesion revascularization at 12 months and 2 years was 2.2% and 2.9%, respectively. CONCLUSIONS: The ARCHeR results demonstrate that extracranial carotid artery stenting with embolic filter protection is not inferior to historical results of endarterectomy and suggest that carotid artery stenting is a safe, durable, and effective alternative in high-surgical-risk patients.

Angioplasty, Balloon↗
PubMed2006

Advancements in carotid stenting leading to reductions in perioperative morbidity among patients 80 years and older.

OBJECTIVE: Patients 80 years and older are generally considered to be at an increased risk for stroke and death from carotid endarterectomy. High-risk status often qualifies them for entry into a carotid angioplasty and stenting (CAS) trial. The aim of this study is to report periprocedure (0-30 d) morbidity and mortality among elderly patients undergoing CAS with and without distal embolic protection in an intention-to-treat analysis. METHODS: A retrospective review was performed to evaluate the medical records and imaging studies of patients 80 years or older who underwent attempted CAS procedures with and without distal embolic protection between June 1996 and February 2004. RESULTS: Ages of the 75 patients identified in our review ranged from 80 to 91 years (average 83.1 yr); 41 were men. Internal carotid artery stenosis ranged from 60 to 95% (mean 78.3%). Forty-two patients had symptoms (transient ischemic attack, 29; stroke, 13), and 33 patients were asymptomatic. Total event rates were major stroke, 4% (3 patients); minor stroke, 6.7% (5 patients); death, 4% (3 patients). Rates in the unprotected group (35 patients) were major stroke, 8.6% (3 patients); minor stroke, 5.7% (2 patients); major stroke/death, 14.3% (5 patients). Rates in the protected group (40 patients) were major stroke, 0; minor stroke, 7.5% (3 patients); major stroke/death, 0; (P < 0.05). CONCLUSION: These results suggest that elderly patients undergoing CAS with adjunctive distal embolic protection are at a lower risk of periprocedure adverse events. Routine clopidogrel use, smaller hardware profile, patient selection, and increased experience likely contributed to these results.

Aged, 80 and over↗
PubMed2006

Acute M2 bifurcation stenting for cerebral infarction: lessons learned from the heart: technical case report.

OBJECTIVE AND IMPORTANCE: Acute ischemic stroke is the third leading cause of death in the United States. For patients with NIHSS scores >10 and evaluated within 6 hours, intra-arterial thrombolysis is the treatment of choice. The Merci retriever (Concentric Medical Inc., Mountain View, CA) and IV TPA are currently the only FDA-approved treatments for acute ischemic stroke. For patients who do not meet the criteria for TPA administration and/or in whom the Merci device fails, options are limited. Intracranial stenting for acute ischemic stroke after failed thrombolysis is now possible because of improved delivery systems and appropriately sized stents. CLINICAL PRESENTATION: A 26-year-old woman presented with an NIHSS score of 11 (right-sided hemiparesis and mixed aphasia) 4 hours from the time of symptom onset. CT perfusion demonstrated increased time to peak in the entire left hemisphere; conventional angiography demonstrated a left M1 occlusion. INTERVENTION: After crossing the occlusion with a microcatheter, reteplase (2 units) was administered into the clot. Mechanical thrombolysis was then attempted, without restoration of flow. Two 3 x 12-mm coronary stents were placed from the M1 into the superior and inferior divisions, respectively, with complete restoration of flow (TIMI 3). Within 72 hours, the patient had an NIHSS score of 1, with a small infarction in the external capsule. CONCLUSION: Novel stroke interventions need to be developed for patients with acute ischemic stroke in whom traditional interventions fail. We present (to our knowledge) the first case of successful revascularization of an acute M1 occlusion accomplished with placement of two coronary stents.

Adult↗
PubMed2006

Stent-assisted intracranial recanalization for acute stroke: early results.

OBJECTIVE: In patients who are not candidates for intravenous tissue plasminogen activator, intra-arterial (IA) therapy is an alternative. Current recanalization rates are 50 to 60% for IA thrombolysis. Stent-assisted recanalization in the setting of acute stroke after failed thrombolysis may improve recanalization rates. METHODS: A retrospective analysis was performed of 19 patients treated at two institutions between July 2001 and March, 2005 with intracranial stenting of a vessel resistant to standard thrombolytic techniques. Demographics, clinical, and radiographic presentation and outcomes were studied. RESULTS: Thirteen men and six women with a median baseline National Institutes of Health Stroke Scale (NIHSS) score of 16 (range, 15-22) were included. Eight lesions were located at the internal carotid artery terminus, seven in the M1/M2 segment, and four in the basilar artery. Average time-to-treatment was 210 +/- 160 minutes. Overall recanalization rate (Thrombolysis in Cerebral Infarction Grade 2 or 3) was 79%. There were six deaths: five due to progression of stroke and withdrawal of care at the family's request and one as the result of a delayed carotid injury after tracheostomy. One postoperative asymptomatic intracranial hemorrhage occurred without adverse affect on outcome. Median discharge NIHSS score of surviving patients was 5 (range, 2.5-11.5). Lesions at the internal carotid artery terminus (P < 0.009), older age (P < 0.003), and higher baseline NIHSS score (P < 0.009) were significant negative outcome predictors, as measured by >3 modified Rankin scale score at discharge. CONCLUSION: Stent-assisted recanalization for acute stroke resulting from intracranial thrombotic occlusion is associated with a high recanalization rate and low intracranial hemorrhage rate. These initial results suggest that stenting may be an option for recalcitrant cerebral arterial occlusions.

Adult↗
PubMed2006

Surgical decompression and coil removal for the recovery of vision after coiling and proximal occlusion of a clinoidal segment aneurysm: technical case report.

OBJECTIVE: We present the case of a patient with continued deterioration of vision after endovascular treatment of an unruptured clinoidal segment aneurysm. In conjunction with a review of the literature, the findings in this case highlight the need for further refinements in our understanding of pathophysiological changes induced by coiling of cerebral aneurysms, especially those in aneurysms producing signs and symptoms relating to mass effect. CLINICAL PRESENTATION: The patient is a 45-year-old man who presented with progressive vision loss. Imaging studies revealed a large, clinoidal segment aneurysm. The patient continued to experience progressive vision loss despite treatment with endovascular coiling, proximal occlusion, and high-dose steroid medication. INTERVENTION: The patient underwent a craniotomy for decompression of the optic nerve and for salvage of vision. Clipping of the distal vessel was performed, and the coil mass was removed. The patient experienced marked improvement of central vision after the surgical procedure. CONCLUSION: Although endovascular treatment of aneurysms protects most patients from aneurysm rupture, this case illustrates the fact that coiling, followed by proximal occlusion, might fail to alleviate symptoms related to mass effect. Our experience in this case suggests that early surgical decompression may be indicated for patients presenting with progressive visual deterioration.

Carotid Artery Diseases↗
PubMed2006

Intravascular ultrasound for intracranial angioplasty and stent placement: technical case report.

OBJECTIVE: Intravascular ultrasound (IVUS) imaging has been used extensively in coronary artery interventions and has provided invaluable information for the understanding and treatment of coronary arterial disease. We present here the first description, to our knowledge, of IVUS-guided intracranial arterial interventions in the clinical setting. CLINICAL PRESENTATION: Two patients underwent intracranial angioplasty and stent placement with the assistance of IVUS for the evaluation of their lesions. One patient underwent stenting to treat an occlusive dissection of the left internal carotid artery that occurred during arteriovenous malformation embolization. Another patient underwent angioplasty and stenting for high-grade restenosis of a basilar artery atherosclerotic lesion. RESULTS: Both patients underwent successful revascularization procedures. The patient with the dissection had a small intraventricular and parenchymal hemorrhage documented by computed tomography 4 hours after treatment, but did not develop hydrocephalus or further hemorrhage. Both patients did well clinically and had no permanent neurological deficits. IVUS provided important information in terms of lesion evaluation, stent selection, and stent placement in each case. CONCLUSION: IVUS of the intracranial circulation may assist the performance of intracranial angioplasty and stenting. It provides useful information that can affect clinical decisions. It may prove to be a valuable tool in clinical use and enhance our understanding of vascular disease of the intracranial circulation, as it has in the coronary circulation.

Aged↗
PubMed2006

Use of heparin-coated stents in neurovascular interventional procedures: preliminary experience with 10 patients.

OBJECTIVE: Currently, there is minimal published data on the use of heparin-coated stents in the neurovasculature; however, these stents have a proven clinical record in the treatment of coronary disease. This article details our experience with the safety and technical aspects of stent deployment in the first 10 patients who had heparin-coated stents placed in the intracranial and cervical vasculature and the preliminary follow-up in most cases. METHODS: We retrospectively reviewed the clinical history, intra- and periprocedural data, and imaging for the patients who received heparin-coated stents in the cervical and intracranial vasculature for cerebrovascular disease between October 2002 and October 2003. RESULTS: Thirteen heparin-coated stents were placed in 10 patients. Seven out of the 10 patients had heparin-coated stents placed in the posterior circulation; the remaining three patients had stents placed in the anterior circulation. Four patients had stents placed intracranially. There was no acute or subacute in-stent thrombosis and no procedure-related complications. Follow-up was performed on most patients, with no clinical symptoms attributable to restenosis in any patient. CONCLUSION: This small series suggests that heparin-coated stents are safe for use in the treatment of cervical and intracranial atherosclerotic disease. Longer-term follow-up is needed to study the heparin coating effect on in-stent restenosis rates and to assess the long-term durability and clinical efficacy of this stent. The use of drug-coated stents in the cerebrovascular circulation is an area that warrants further investigation.

Adult↗
PubMed2006

Current concepts in the management of intracranial atherosclerotic disease.

Medically refractory, symptomatic intracranial atherosclerotic disease has a poor prognosis. Based on the results of the Warfarin-Aspirin Symptomatic Intracranial Disease study, the risk of ipsilateral stroke at 1.8 years is between 13 and 14% in patients with symptomatic intracranial atherosclerosis. Synergistic advances in intracranial angioplasty and stenting, modern neuroimaging techniques, and periprocedural and postprocedural antithrombotic regimens are creating new models for the diagnosis and successful endovascular treatment of intracranial stenosis. In this article, the most recent clinical developments and concepts for the diagnosis and endovascular treatment of intracranial atherosclerotic disease are discussed.

Angioplasty↗
PubMed2006

Giant cerebral aneurysms: endovascular challenges.

OBJECTIVE: Giant (>or=25 mm in diameter) cerebral aneurysms have a poor natural history, with high risks of subarachnoid hemorrhage or progressive disability or death caused by mass effect or stroke. Surgical treatment may be effective but carries a high burden of morbidity and mortality. Thus, attempts at endovascular solutions to these complex lesions have been developed to offer therapy at reduced risk. METHODS: The authors reviewed their clinical experience and the current body of literature concerning giant cerebral aneurysms and present their perspective on the current state of the art in endovascular therapy for these aneurysms. A variety of techniques are described that can be used in an attempt to provide a solution to the wide variety of clinical dilemmas associated with the management of these difficult lesions. Preprocedural planning and periprocedural considerations are discussed briefly. The use of intracranial balloons and stents are described in conjunction with the use of detachable platinum coils. The developing concept of using stents alone to treat aneurysms is discussed. Alternative methods of treating giant aneurysms are discussed. RESULTS: Current endovascular approaches, when properly selected and applied, can provide lower-risk therapies than conventional microsurgical approaches for patients harboring giant cerebral aneurysms. However, endovascular approaches do not, at present, provide results that are as durable as current surgical techniques for giant cerebral aneurysms. CONCLUSION: Treatment of giant cerebral aneurysms via endovascular therapeutics requires the interventionist to possess an extensive armamentarium. Meticulous preprocedure evaluation, patient selection, and execution of the treatment plan enable safe and effective management. Current therapies do not provide an ideal solution for every patient, so one must consider creative and evolving solutions to these difficult clinical challenges. The procedural morbidity of open surgery versus the decreased durability of current endovascular techniques must be assessed carefully.

Blood Vessel Prosthesis↗
PubMed2006

Training in cerebrovascular disease: do we need to change the way we train residents?

With the ongoing development of endovascular techniques and technologies, treatment of cerebrovascular disease is evolving at a fast pace. For neurosurgery to maintain a leadership role in the treatment of these disorders, modifications in neurosurgical training programs are essential. In this article, we discuss the changes perceived to enable residents to acquire the multifaceted understanding and skill set necessary to meet the new clinical reality and prepare to become the leaders of tomorrow in the management of cerebrovascular disease.

Cerebrovascular Disorders↗
PubMed2006

Cervical carotid revascularization: the case for carotid angioplasty with stenting.

Carotid artery angioplasty with or without stent placement has evolved as an alternative to carotid endarterectomy, particularly for those patients in whom carotid endarterectomy is associated with a higher risk of complications. This article summarizes the selection criteria for participation in and the results of several carotid intervention trials, reviews the relative indications and limitations for both surgical and endovascular revascularization approaches, and describes the technique for and results associated with carotid stenting. The discussion is presented from the vantage of neurosurgeons who are experienced in both revascularization approaches.

Angioplasty↗
PubMed2006

Workforce needs for endovascular neurosurgery.

During the past decade, endovascular techniques and clinical experience have matured to the point that all or a significant part of the treatment of acute ischemic stroke, cerebral aneurysms, brachiocephalic occlusive disease, and arteriovenous fistulae or malformations is performed in angiography suites by neuroradiologists, vascular surgeons, peripheral interventionists, cardiologists, neurologists, and neurosurgeons worldwide. With improvements in technology and lower morbidity rates, the scope of endovascular techniques will only increase. Currently, in the United States alone, this amounts to a volume of more than 500,000 patients annually. Neurosurgeons currently provide only a small portion of the care of these patients. The workforce needs for endovascular surgeons in neurosurgery will be determined by the patients, the willingness of neurosurgeons to embrace endovascular techniques, and the broad scope of cerebrovascular disorders that can be treated.

Career Mobility↗
PubMed2005

Intraarterial reteplase and intravenous abciximab for treatment of acute ischemic stroke. A preliminary feasibility and safety study in a non-human primate model.

We performed a preliminary feasibility and safety study using intravenous (IV) administration of a platelet glycoprotein IIb/IIIa inhibitor (abciximab) in conjunction with intraarterial (IA) administration of a thrombolytic agent (reteplase) in a primate model of intracranial thrombosis. We introduced thrombus through superselective catheterization of the intracranial segment of the internal carotid artery in 16 primates. The animals were randomly assigned to receive IA reteplase and IV abciximab ( n =4), IA reteplase and IV placebo ( n =4), IA placebo and IV abciximab ( n =4) or IA and IV placebo ( n =4). Recanalization was assessed by serial angiography during the 6-h period after initiation of treatment. Postmortem magnetic resonance (MR) imaging was performed to determine the presence of cerebral infarction or intracranial hemorrhage. Partial or complete recanalization at 6 h after initiation of treatment (decrease of two or more points in pre-treatment angiographic occlusion grade) was observed in two animals treated with IA reteplase and IV abciximab, three animals treated with IA reteplase alone and one animal treated with IV abciximab alone. No improvement in perfusion was observed in animals that received IV and IA placebo. Cerebral infarction was demonstrated on postmortem MR imaging in three animals that received IA and IV placebo and in one animal each from the groups that received IA reteplase and IV abciximab or IV abciximab alone. One animal that received IV abciximab alone had a small intracerebral hemorrhage on MR imaging. IA reteplase with or without abciximab appeared to be the most effective regimen for achieving recanalization in our model of intracranial thrombosis. Further studies are required in experimental models to determine the optimal dose, method of administration and efficacy of these medications in acute ischemic stroke.

Abciximab↗