Effect of the distal-balloon protection system on microembolization during carotid stenting.

BACKGROUND: The distal-balloon protection system is being evaluated for its efficacy in preventing embolic neurological events during carotid stenting (CAS). We sought to determine the effect of this system on the frequency of Doppler-detected microembolic signals (MES) during CAS. METHODS AND RESULTS: Using transcranial Doppler, we compared the frequency of MES during CAS in 2 groups: 39 patients without distal protection and 37 who used the distal-balloon protection system (GuardWire). There were no significant differences in the clinical or angiographic characteristics between the 2 groups. Three phases with increased MES counts were identified during unprotected CAS; these were stent deployment, predilation, and postdilation (75+/-57, 32+/-36, and 27+/-25 METS, respectively). The distal-balloon protection significantly reduced the frequency of MES during CAS (MES counts: 164+/-108 in the control versus 68+/-83 in the protection group; P=0.002), particularly during these 3 phases. MES in the protection group were detected predominantly during sheath placement, guidewire manipulation, and distal-balloon deflation. CONCLUSION: Three phases with increased MES counts were identified during unprotected CAS (eg, stent deployment, predilation, and postdilation). The distal-balloon protection system significantly reduced the frequency of MES during CAS, particularly during these 3 phases.

Immediate and late clinical outcomes of carotid artery stenting in patients with symptomatic and asymptomatic carotid artery stenosis: a 5-year prospective analysis.

BACKGROUND: Carotid stenting is a less invasive percutaneous procedure than carotid endarterectomy for the treatment of carotid stenosis. Reports suggest that it can be performed with periprocedural complication rates similar to those of carotid endarterectomy. The purpose of this study was to determine short- and long-term outcomes in the largest prospective cohort of carotid stenting patients. METHODS AND RESULTS: This study followed 528 consecutive patients (604 hemispheres/arteries) undergoing carotid stenting. There was a 0.6% (n=3) fatal stroke rate and 1% (n=5) nonstroke death rate at 30 days. The major stroke rate was 1% (n=6), and the minor stroke rate was 4.8% (n=29). The overall 30-day stroke and death rate was 7.4% (n=43). Over the 5-year study period, the 30-day minor stroke rate improved from 7.1% (n=7) for the first year to 3.1% (n=5) for the fifth year (P:<0.05 for trend). The best predictor of 30-day stroke and death was age >/=80 years. After the 30-day period, the incidence of fatal and nonfatal stroke was 3.2% (n=31). On Kaplan-Meier analysis, the 3-year freedom from ipsilateral or fatal stroke was 92+/-1%. CONCLUSIONS: Experience from a single group of operators demonstrates that carotid stenting can be performed with an acceptable 30-day complication rate. Late follow-up also demonstrates a low rate of fatal and nonfatal stroke. These results suggest that carotid stenting may be comparable to carotid endarterectomy, and it underscores the clinical equipoise and premise for the National Institute of Health-supported, randomized Carotid Revascularization Endarterectomy Versus Stent Trial comparing carotid stenting with carotid endarterectomy.

Carotid artery stenting for the high surgical risk patients.

Obstructive atherosclerotic carotid bifurcation disease is responsible for approximately 30% of stroke cases in the United States. Any successful treatment of this disease should demonstrate significant and durable reduction in the related risk for stroke without compromising the patient safety. The indications for CAS are evolving as the techniques, the stents and catheter technology advance. There is an ongoing need to improve the equipment suitable for carotid stenting and a need to enhance the safety of the procedure. Often, when a technical problem is encountered, it is attributed to the inadequacy of the devices currently available. As the technology improves, particularly with the application of the anti-embolization devices, the indications and contraindication may need to be revised.

Procedural safety and short-term outcome of ambulatory carotid stenting.

BACKGROUND AND PURPOSE: Ambulatory procedures increase patient comfort and enhance cost-effectiveness. We sought to determine the feasibility and safety of ambulatory carotid stenting. METHODS: A selected group of patients was admitted and discharged the same day after the carotid stenting procedure. Immediate and short-term outcomes are reported. RESULTS: A total of 98 ambulatory carotid stenting procedures (98 hemispheres in 92 patients) were performed. There were 66 men (72%), and the mean age was 70+/-9 years. Of the patients, 28% had neurological symptoms related to the treated artery within 3 months before the procedure. Sixteen percent of the patients had prior carotid endarterectomy, 4% had prior ipsilateral neck radiation, and 8% had complete occlusion of the contralateral internal carotid artery. Successful access site hemostasis was ensured in all patients with suture-mediated vascular closure devices in 96 (98%) and manual compression in 2. Clinical follow-up was available for 96% of the patients at a mean time of 6+/-4 months. There were no neurological events, deaths, repeated procedures, or major access site complications. CONCLUSIONS: Ambulatory carotid stenting is both safe and feasible. This approach will enhance the applicability of the procedure by increasing patient comfort and potentially reducing procedural costs.

Consultation before thrombolytic therapy in acute myocardial infarction. Second National Registry of Myocardial Infarction (NRMI 2) Investigators.

Among 57,398 thrombolytic recipients in the National Registry of Myocardial Infarction 2, consultation with another physician was sought in 64% before initiating lytic therapy, although presenting features were typical, rather than atypical, in most patients. Consultation significantly delayed the administration of lytic therapy and was associated with increased hospital mortality.

Early results of percutaneous intervention for severe coexisting carotid and coronary artery disease.

Fifty-one patients with severe coexisting carotid and symptomatic coronary artery occlusive disease successfully underwent staged or simultaneous coronary angioplasty and carotid stenting. One pericardial effusion and 2 minor strokes with full recovery occurred in the hospital, but no major neurologic events, myocardial infarction, or death were observed and no repeat revascularization was required within the 30-day follow-up.

Carotid artery stenting in patients with high neurologic risks.

Forty-four patient with high neurologic risks (Mayo class IV) successfully underwent carotid artery stenting with combined major stroke and death rates of 4.5%. Late follow-up at a mean of 23 +/- 1.8 months showed 1 non-neurologic death, but no neurologic events or repeat stenting procedures.

Stenting of symptomatic stenosis of the intracranial internal carotid artery.

Percutaneous balloon angioplasty has been reported to be useful in the treatment of intracranial atherosclerotic arterial stenoses; however, arterial dissection with increased risk of stroke has limited its widespread implementation. Although vascular stenting has improved the outcome of similar procedures in the extracranial vasculature, its intracranial application has been limited by the lack of suitable stents. We report a case of successful percutaneous stenting of a symptomatic intracranial carotid artery using a second-generation, flexible, coronary stent.

Extracranial vertebral artery stent placement: in-hospital and follow-up results.

OBJECT: The authors summarize their experience with stent deployment in the treatment of vertebrobasilar artery (VBA) insufficiency. This is an underdiagnosed condition, and the incidence of significant vertebral artery (VA) stenosis has been underappreciated. Medical therapy has been the mainstay of treatment because of the high rate of morbidity associated with surgical correction of VA stenosis. Recently, some authors have reported acceptable results with the use of percutaneous transluminal angioplasty, but this technique has significant weaknesses such as elastic recoil and problems in achieving safe treatment of dissections. METHODS: The authors investigated the feasibility, safety, and outcome of VA stent placement in 50 patients in whom 55 vessels were treated using stents. Technical success was achieved in 54 (98%) of 55 vessels, with no procedure-related complications. However, one patient (2%) died of nonneurological causes, and one (2%) suffered a stroke that occurred within the 30-day postprocedural period and was related to a complicated coronary intervention. Clinical follow-up review performed at a mean of 25 +/- 10 months revealed two patients (4%) with recurrence of VBA symptoms. Six-month angiographic follow up was completed in 90% of eligible patients, with a 10% incidence of restenosis as defined by greater than 50% luminal narrowing. CONCLUSIONS: Vertebral artery stent placement is feasible in patients who have significant VA stenosis, with predictably good angiographically demonstrated and clinical results. The 6-month angiographically confirmed restenosis rate appears to be low, as does the clinical recurrence rate. This technique solves the problems of elastic recoil and the treatment of angioplasty-induced dissections. Further prospective comparison with medical preventive strategies is warranted.

Techniques of carotid artery stenting: the state of the art.

The technique of carotid stenting has undergone significant refinement since its introduction and continues to improve as experience with the procedure matures and more suitable equipment becomes available. Improved stent designs and the utilization of cerebral protection devices are expected to significantly impact on the technique, its ultimate outcomes, and widespread application. In using the currently available technology for carotid stenting, patient selection and meticulous attention to procedural details are very important in minimizing embolic events. In this article, we provide a comprehensive practical discussion of the state-of-the-art carotid stenting techniques that have allowed us to maintain low event rates.

Microembolization during carotid stenting with the distal-balloon antiemboli system.

BACKGROUND: The distal-balloon protection system is being evaluated for its efficacy in preventing embolic neurological events during carotid stenting (CAS). We sought to determine the effect of this system on the frequency of the Doppler-detected microembolic signals (MES) during CAS. METHODS: Using transcranial Doppler, we compared the frequency of MES during CAS in 2 groups; 39 patients without distal protection and 37 with the distal-balloon protection system (GuardWire, Percusurge, Sunnyville, CA). There was no significant difference in the clinical or angiographic characteristics between the 2 groups. Three phases with increased MES counts were identified during the unprotected CAS; stent deployment, predilation, and postdilation (mean+/-SD: 75+/-57, 32+/-36, and 27+/-25, respectively). RESULTS: The distal-balloon protection significantly reduced the frequency of MES during CAS (MES-counts: 164+/-108 in the control vs 68+/-83 in the protection group, p=0.002) particularly during these 3 phases. MES in the protection group were detected predominantly during sheath placement, guidewire manipulation and during the distal-balloon deflation. CONCLUSIONS: Three phases with increased MES counts were identified during the unprotected CAS, e.g. stent deployment, predilation and postdilation. The distal-balloon protection system significantly reduced the frequency of MES during CAS, particularly during these 3 phases.

Simultaneous bilateral carotid stenting for restenosis after endarterectomy.

Carotid stenting may offer an alternative to surgery for recurrent carotid artery stenosis following endarterectomy. Five patients successfully underwent percutaneous simultaneous bilateral carotid artery stenting for restenosis after endarterectomy, without complications. Six months of clinical and imaging follow-up showed preserved patency of all vessels treated, with no neurologic events in any of the patients.

Carotid stenting with distal-balloon protection via the transbrachial approach.

PURPOSE: To document the feasibility of brachial artery access for carotid stenting with distal-balloon protection of the internal carotid artery (ICA). TECHNIQUE: Via percutaneous access to the brachial artery, a large double-curve catheter is advanced into the aortic arch over a hydrophilic guidewire to cannulate the left common carotid artery. Following sheath exchange, a GuardWire distal-protection balloon is positioned within the left ICA distal to the stenosis. The lesion is dilated, followed by deployment and dilation of a self-expanding stent. Transcranial Doppler monitoring shows only scarce microembolic signals during the procedure. CONCLUSIONS: Carotid stenting with distal balloon protection via the brachial artery appears feasible as an alternative to standard femoral access.

Percutaneous treatment of catheter-induced dissection of the left main coronary artery and adjacent aortic wall: a case report.

Left main coronary artery dissection complicating selective coronary angiography is uncommon. Moreover, aortic root dissection associated with coronary intervention is underreported and may require urgent surgical intervention. During percutaneous coronary angioplasty of a catheter-induced left main coronary artery dissection, retrograde dissection of the adjacent aortic root occurred. Both were successfully treated by stenting of the left main coronary artery. Cathet. Cardiovasc. Intervent. 49:86-89, 2000.

Carotid stenting for severe radiation-induced extracranial carotid artery occlusive disease.

PURPOSE: To present our experience with carotid artery stenting as an alternative treatment to endarterectomy in patients with radiation-induced carotid artery occlusive disease. METHODS AND RESULTS: Fourteen patients (10 males; mean age 61 years, range 52 to 79) underwent percutaneous stenting of 15 carotid arteries for severe radiation-induced extracranial stenoses. Technical success was achieved in all patients, with reduction of the mean stenosis from 77% +/- 6% to 8% +/- 2%. In 2 patients, ipsilateral vertebral artery lesions were stented concomitantly. One patient had a minor stroke after the procedure but recovered fully in 2 days. No other complications were encountered. Nine (64%) patients had 6-month follow-up imaging (angiography or duplex scanning) that showed no evidence of restenoses (obstruction > or = 50%). At 18 +/- 2 months, 3 (21%) patients had died from unrelated causes. No neurological events occurred, and no repeat carotid artery interventions were required in the remaining patients. CONCLUSIONS: Carotid stenting is an effective treatment option for severe radiation-induced carotid artery occlusive disease.

Embolization via collateral circulation during carotid stenting with the distal balloon protection system.

PURPOSE: To describe a potential route for embolization to the middle cerebral artery (MCA) during carotid stenting with the distal balloon protection system. CASE REPORT: An 82-year-old man with symptomatic severe carotid artery stenosis underwent elective carotid stenting with distal-balloon protection. Despite complete occlusion of the distal internal carotid artery, frequent emboli were detected in the ipsilateral MCA by transcranial Doppler (TCD) during the procedure. Intracranial angiography, performed during the distal-balloon protection, revealed filling of the MCA through collaterals from the ipsilateral external carotid artery. The procedure was successfully completed without complications. The patient remains asymptomatic at 6 months. CONCLUSIONS: During carotid stenting with distal-balloon protection, asymptomatic embolization into the ipsilateral MCA may occur through collateral circulation. The clinical significance of these emboli is uncertain.

Subarachnoidal hemorrhage following carotid stenting with the distal-balloon protection.

A 61-year-old man underwent carotid stenting with the distal-balloon protection system for symptomatic carotid artery stenosis. During the procedure, progressive elevation of the systolic blood pressure occurred, reaching a peak of 220 mm Hg immediately following deflation of the distal balloon. This was associated with severe headaches and progressive deterioration in the mental status to a coma. Head CT scan showed massive subarachnoidal hemorrhage contralateral to the stented side and a secondary intracerebral hemorrhage. Despite immediate successful blood pressure control, his condition deteriorated and he died 2 days later.

Immediate and late outcomes of subclavian artery stenting.

Stenting for subclavian artery occlusive disease is being increasingly utilized. To determine the immediate and late outcome of subclavian artery stenting, we studied 38 consecutive patients in whom the procedure was attempted. Technical and clinical success was achieved in 35 patients without complications. Failures occurred only in completely occluded arteries. Late clinical success was demonstrated in 31 patients. Three patients had recurrent symptoms. Two had angiographic restenosis within 4 months of the procedure; both were successfully redilated. The third patient had a new lesion, which was successfully stented. One patient died from lung cancer 10 months after the procedure. We conclude that stenting for subclavian artery occlusive disease has favorable immediate and late clinical outcomes and may be considered as a primary therapy.