Carotid artery revascularization in high surgical risk patients with the NexStent and the Filterwire EX/EZ: 1-year results in the CABERNET trial.

OBJECTIVE: The multicenter, single-arm CABERNET trial evaluated outcomes in high-surgical-risk patients with carotid artery stenosis treated with the NexStent plus FilterWire EX/EZ Emboli Protection System. BACKGROUND: For patients at high surgical risk, carotid artery stenting (CAS) offers a less invasive alternative to carotid endarterectomy (CEA). METHODS: The trial enrolled 454 high-surgical-risk patients with carotid stenosis by angiography > or = 50% for symptomatic patients and > or = 60% for asymptomatic patients. The comparator primary endpoint was the 1-year major adverse event (MAE, defined as any death, stroke, or myocardial infarction [MI]) rate. It was compared with a proportionally weighted objective performance criterion (OPC) of 12.1% representative of published CEA results in similar patients plus a prespecified noninferiority margin (delta) of 4%. A second primary endpoint was the composite rate of 30-day MAE plus late (31-365 days) ipsilateral stroke. RESULTS: Symptoms of carotid stenosis were present in 24.2% of patients; 36.6% of patients were considered high-surgical-risk due to comorbid risk factors and 63.4% due to anatomic risk factors. The rate of 30-day MAE plus late ipsilateral stroke was 4.7% (20/438). The comparator primary endpoint of 1-year MAE was 11.6% (51/438) and was noninferior to the OPC of 12.1% (95% upper confidence interval of 14.5% versus OPC plus delta of 16.1%, P = 0.005). Late ipsilateral stroke was 0.7% and target vessel revascularization at 1 year was 2.4%. CONCLUSIONS: The CABERNET trial demonstrates that CAS with NexStent and FilterWire is noninferior to (equivalent or better than) traditional CEA at 1 year in high-surgical-risk patients based on historical controls.

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.

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.

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.

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.

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.

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.

Perforation of external carotid artery branch arteries during endoluminal carotid revascularization procedures: consequences and management.

The purpose of this article is to describe several inadvertent perforations of external carotid artery branches that occurred in our laboratory during planned carotid artery stenting procedures. When known, the mechanism of the perforation is described. The treatment of these complications is discussed, along with a more general discussion of potential embolic materials. Perforation of branch arteries within the external carotid artery territory during planned carotid revascularization is an uncommon but potentially life-threatening complication. This complication can occur as a result of wire or catheter placement into these vessels. Early recognition of the perforation, prompt treatment of the bleeding, and control of the patient's airway are necessary to avoid a potentially catastrophic outcome.

Atherosclerotic occlusive extracranial vertebral artery disease: indications for intervention, endovascular techniques, short-term and long-term results.

BACKGROUND: Atherosclerotic occlusive disease of the vertebral artery (VA) affects a significant proportion of patients with cerebrovascular disease and can cause significant morbidity and mortality despite maximal medical therapy. Careful selection of both symptomatic and asymptomatic patients for intervention based on neurological symptoms, as well as anatomical and hemodynamic considerations, is essential. METHODS: To achieve proper results with angioplasty and stenting, standard endovascular techniques are modified for the unique anatomical considerations of the VA. Several technical nuances are described here to aid in the endoluminal revascularization of the VA. RESULTS: Technical success (<50% residual diameter stenosis) rates ranging from 94 to 98% and low rates of periprocedural complications have been achieved with VA angioplasty and stenting in select series with angiographic follow-up. The long-term success in those series is limited by the high (10-43%) rate of recurrent stenosis. Proper placement of the stent can reduce the risk of periprocedural complications and restenosis. In-stent stenosis appears most commonly during the first 6-12 months after stent placement, but does not appear to correlate with return of neurological symptoms. We believe the high rate of recurrent stenosis makes follow-up angiography essential, especially in the first 12 months after the procedure. CONCLUSION: Endovascular VA angioplasty with stent placement provides an innovative approach to treat a difficult clinical entity. Evolving therapies, including drug-eluting stents or bioresorbable stents, may prove to provide better long-term results.