Adjunctive pharmacologic treatment for elective stenting of the extracranial carotid arteries

Endovascular stenting of the extracranial carotid arteries is a viable treatment option to carotid endarterectomy in selected patients. Patients undergoing this procedure must be treated with aspirin 325 mg at least 24 hours prior to the procedure and clopidogrel 75 mg oral, three to five days prior to the procedure (or 300 mg at least six hours prior to stenting). During the intervention, heparin is given to maintain an activated clotting time of at least 300 seconds. Although there are theoretical advantages on the use of a platelet IIb/IIIa inhibitor, their routine use during elective carotid stenting is not recommended until their clinical benefits have been clearly demonstrated in this patient population. Hemodynamic instability during balloon inflation and stent deployment should be treated with intravenous fluids, atropine, and an alpha agonist such as neosynephrine. All the oral antihypertensive must be discontinued after the procedure and if there is persistence of hypotension making discontinuation of neosynephrine difficult, an oral alpha agonist such as midodrine (2.5 to 5 mg two to three times daily) is helpful. In the majority of patients this medication can be tapered off three to five days following stenting.     

Angioplasty and stenting of extracranial vertebral artery stenosis.

Percutaneous angioplasty and stent placement seem a useful technique for the treatment of vertebro-basilar insufficiency and the first treatment to be proposed. This technique appears safe and effective for alleviating symptoms and improving blood flow to the cerebral circulation, with a low complications rate and good long-term results. However, this procedure needs experienced interventionists to choose the stent and have appropriate placement of the stent in the ostium of the vertebral artery (VA). The tortuosity of the VA may be technically challenging. The new coronary stents seem to be well suited to treat atherosclerotic lesions of the origin and of the proximal VA. A large variability of restenosis risk has been reported. Drug eluting stents may be the solution. Prospective randomized studies are needed to demonstrate the clinical effectiveness of VA stenting in stroke prevention, its durability, and to define more clearly its indications.     

Angioplasty and stenting for the occluded internal carotid artery

To investigate the feasibility and efficacy of angioplasty and stenting for symptomatic occlusion of carotid artery. From December 2004 to June 2009, 17 patients with progressive or reoccurred ischemic stroke or repeated transient ischemic attack resulted from the total occluded carotid artery underwent angioplasty and stenting were reviewed. All patients with successful procedure were followed up. Clinic and angiography data were documented prospectively. The median time from symptoms onset to procedure was 23 days (range 3–94 days). Twelve of the 17 patients (70%) were obtained technique success. Eight patients were observed the collapse of internal carotid artery between occluded location to origin of ophthalmic artery after the occlusion was patent. Two patients had clots which were solved with urokinase. The collapsed internal carotid artery was improved markedly in the compute tomography angiograph 7 days after the procedure. No any complications related procedures occurred. One patient died from myocardial infarct and one suffered from ischemic minor stroke in brainstem for a median follow-up of 346.5 days. One of 9 patients (11.1%) was observed in-stent stenosis in the follow-up angiography. Angioplasty and stenting was a potential alternative therapy for symptomatic occlusion of carotid artery. Further study is required to determine the safety of this treatment.     

Outcomes following extracranial carotid artery stenting in high-risk patients

BACKGROUND: Carotid artery angioplasty and stenting has become a viable alternative to carotid endarterectomy (CEA), especially for patients considered at high risk for post-operative complications. This study investigated the feasibility, safety and long-term outcome of carotid artery stenting (CAS) in high-risk patients. METHODS: From July 1995 to November 2000, sixty-two consecutive patients considered to be at high risk for post-operative complications of CEA were followed prospectively after undergoing extracranial CAS procedures. RESULTS: Sixty-two patients [37 men (60%) and 25 women (40%)] underwent a total of 69 CAS procedures. The mean age was 67 +/- 9 years (range, 32-89 years). Comorbid conditions included hypertension in 95% and severe coronary artery disease in 58%. Sixteen patients (26%) had a previous ipsilateral CEA, twenty-one percent had a history of neck radiation and 32% had a history of significant contralateral carotid artery disease. Fifty-two patients (84%) were symptomatic. All 69 CAS procedures were technically successful. The major post-operative complications were two minor strokes (2.8%), one major stroke (1.4%) and one fatal major stroke (1.4%). The mean length of follow-up was 17 months (range, 4 months to 5.6 years). Two patients (2.8%) have suffered ipsilateral neurologic events following CAS. Long-term follow-up revealed restenosis at 6 months in 4 patients (5.7%). CONCLUSIONS: Carotid artery angioplasty and stenting is safe and feasible. This procedure produces satisfactory outcomes in patients who are at high risk for post-operative complications of CEA.     

症状性颈内动脉起始段狭窄血管内自膨式支架治疗26例

目的探讨血管内自膨式支架技术治疗症状性颈内动脉起始段狭窄的临床效果。 方法对26例患者颈内动脉起始段狭窄的患者行全脑血管造影,依照北美有症状颈动脉内膜切除试验测量标准,判断颈动脉狭窄程度,对狭窄率>50％的患者置入自膨式支架,术中5例行球囊预扩张,3例应用保护装置。结果 26例支架置入均获成功,血管残余狭窄程度<30％。术后随访23例(10-22个月),1例发生再狭窄(狭窄率>55％)。结论 血管内支架成形术是治疗颈动脉狭窄的一种有效方法,至于术后存在的血栓形成、再狭窄等问题还有待于今后进一步研究。     

颅外颈动脉和椎动脉狭窄支架置入术围术期并发症及危险因素分析

目的探讨血管内支架置入术治疗颅外颈动脉和椎动脉狭窄患者围术期并发症特点及危险因素,制订术前评估策略。方法连续选择我院行血管内支架置入术的患者279例,根据手术方式分为:颈动脉支架组207例及椎动脉支架组72例,术后随访30d,根据围术期内是否存在并发症分为并发症组144例和无并发症组135例。结果颈动脉支架组心动过缓(10.6%vs 1.4%,P=0.027)及血压降低(22.7%vs 5.6%,P=0.001)的比例明显高于椎动脉支架组。并发症组患者随着年龄、狭窄程度的增加,并发症比例明显升高,而无并发症组明显降低(P0.05)。logistic回归分析显示,年龄、高血压、动脉狭窄程度、狭窄长病变、Ⅲ型主动脉弓、术者操作经验及操作时间为围术期并发症的独立危险因素,球囊预扩为围术期并发症的保护因素。结论患者相关因素及术中因素均可显著影响围术期并发症的发生,术前充分准备、术中规范操作及术后严密监测对防治围术期并发症尤为重要。     

High prevalence of obstructive lesions of the extracranial carotid arteries in reno-vascular hypertension

Ischemic stroke represents a leading cause of death in patients with renovascular hypertension. In the vast majority it is related to obstructive lesions of the extracranial tracts of the carotid arteries. Since no data were previously available on carotid artery lesions in patients (pts) with renovascular hypertension, a prospective case-control study was undertaken to assess the prevalence of carotid artery lesions in renovascular hypertension. Nineteen pts (10 females and 9 males, age: 26-77 yrs) with a diagnosis of renovascular hypertension based on the presence of uni- or bilateral renal artery stenosis and favourable outcome after either percutaneous transluminal renal angioplasty or surgery, and/or renal vein studies, were evaluated. The cause of renal artery stenosis was atherosclerosis in 12 pts and fibrodysplasia in 7. Each pt was matched with a control pt with primary hypertension for sex, race, age, blood pressure levels, smoking habits and serum cholesterol levels. Carotid artery lesions were assessed using a high resolution echo-Doppler (Duplex) system (Biosound 2000, probe 4 cm, 8 mHz). After the matching, the two groups were almost identical in terms of demographic features and risk profile. In the control group the prevalence of carotid artery lesions was similar to that reported in the literature. On the contrary, a highly significant higher prevalence of carotid artery lesions was observed in the pts with renovascular hypertension (92.1 vs 42.1%, respectively; p less than 0.001). Subgroup analysis showed that this difference was found mainly in pts with atherosclerotic renal artery stenoses.(ABSTRACT TRUNCATED AT 400 WORDS)     

Value of ultrasound in the diagnosis of aneurysms of the extracranial internal carotid arteries

Aneurysms of the extracranial carotid arteries are a rare abnormalitiy and may represent a diagnostic challenge in examination of the patients. B-flow is a new digital vascular ultrasound technique and is an especially reliable method in the diagnosis of the extracranial portion of the internal carotid arteries as it shows less flow artifacts than color-coded Doppler sonography (CCDS) and power Doppler (PD). This review compares color-coded Doppler sonography, power Doppler and B-flow findings in extracranial ICA and CA aneurysm to emphasize the usefulness of B-flow in this clinical condition.     

Protection filter-related events in extracranial carotid artery stenting: a single-center experience.

PURPOSE: To report the complications, rescue procedures, and consequences related to the use of an embolus protection filter during carotid artery stenting (CAS). METHODS: A retrospective review was undertaken of 72 patients (58 men; mean age 70.0+/-8.2 years, range 56-87) with extracranial atherosclerotic carotid stenosis who underwent 77 CAS procedures under filter protection. Filter-related events and rescue procedures according to each procedural step were retrospectively evaluated on CAS angiograms. In addition, neurological events and outcomes were also assessed. RESULTS: CAS using a filter was successful in 99% of cases, and the overall rate of minor stroke (n=1), major stroke (0), or mortality (n=1) was 2.6% at 30 days. Filter placement was successful in all cases. However, arterial tortuosity made it difficult for a filter to pass through the stenosis in 1 case; this was overcome with an additional supportive wire (0.018-inch). Filter-related events were flow impairment in 6 (7.8%), filter wedging in the catheter tip in 4 (5.2%), vasospasm >50% narrowing in 7 (9.1%), filling defects within the filter membrane in 5 (6.5%), retrieval failure with the provided retriever in 3 (3.9%), and insecure retrieval without filter collapse in 2 (2.6%). Flow impairment caused drowsy mentality and impaired verbal response in 4, which resolved after prompt filter retrieval. All the cases of filter wedging were resolved with a catheter pulled down into the stented segment to separate the filter element from the catheter tip. Significant vasospasm and filling defects were spontaneously resolved in all cases after filter retrieval. Inability to pass a retriever catheter through a stent was overcome with curved 5-F catheter manipulation in all 3 cases. CONCLUSION: The use of a filter during CAS may induce various angiographic or technical events at each step. For a severely stenotic and tortuous carotid lesion with difficult access, a filter may become trapped or irretrievable during flow arrest. Physicians should be aware of the preventive and rescue maneuvers to counter filter-related events, perhaps even considering another type of protection mechanism or carotid endarterectomy.     

Noninvasive evaluation of the extracranial carotid arteries in patients with cerebrovascular events and atrial fibrillations

Noninvasive carotid artery testing was performed in 73 patients with nonvalvular atrial fibrillation who were referred because of symptoms or signs of cerebrovascular disease. Thromboembolism related to atrial fibrillation without valvular heart disease was the probable source of cerebral ischemia in 25 (80%) of 31 patients with stroke and coexisting atherosclerotic disease at the carotid artery bifurcation in six (20%). Nonvalvular atrial fibrillation was the probable source of symptoms in nine (70%) of 13 of patients with transient cerebral ischemia, while coexisting carotid artery disease was present in four (30%). Nonvalvular atrial fibrillation accounted for the symptoms in four of five patients with amaurosis fugax, with atherosclerotic carotid artery disease present in one. The remaining 24 patients had nonhemispheric symptoms of cerebrovascular disease, including vertebrobasilar insufficiency, dizziness, and syncope, and only one had a carotid lesion. A significantly higher proportion of patients with focal hemispheric symptoms had coexisting carotid disease than patients with nonfocal symptoms had, suggesting that atherosclerotic cerebrovascular disease contributes to stroke in patients with nonvalvular atrial fibrillation. Noninvasive carotid artery testing may be helpful in identifying atherosclerotic lesions at the carotid artery bifurcation in patients with atrial fibrillation and cerebrovascular disease, because different therapeutic modalities may be appropriate when two potential sources of cerebral ischemia are present.     

脑CT灌注成像联合颈动脉高分辨磁共振成像在颅外段颈动脉狭窄诊断及支架成形术中的应用

目的:探讨脑CT灌注成像(CTP)联合颈动脉高分辨磁共振成像(HR-MRI),在颈动脉狭窄诊断及支架置入术中的评估价值。方法:经颈动脉B超证实颅外段颈动脉重度狭窄90例患者,行脑CTP联合颈动脉HR-MRI检查,对结果分析、评估基础上,选取合适的颈动脉支架置入。结果:共筛查85例症状性颈动脉狭窄患者为颈动脉内膜剥脱术的高危患者,其中CTP异常75例。最终64例颈动脉狭窄患者存在易损斑块(含纤维帽破裂、斑块内出血),行闭环自膨支架治疗,余21例患者行开环自膨支架置入,术中所有患者使用保护伞装置。手术成功率97.6%,围手术期内出现1例脑叶出血、1例下肢静脉血栓,未发生缺血性脑血管病。结论:脑CTP联合颈动脉HR-MRI可充分评估颈动脉狭窄程度,并了解狭窄段管腔斑块成分,为颈动脉支架的选择及降低围手术期风险提供重要指导。     

Intracranial revascularization therapy: Angioplasty and stenting

Opinion statement  Depending on the population studied, intracranial atherosclerosis accounts for 10% to 29% of ischemic brain events. A significant number of patients with intracranial atherosclerosis continue to suffer from repeated strokes or transient ischemic attacks despite optimal medical management. In selected patients, intracranial angioplasty with or without stenting is a promising treatment option. Patient selection, careful periprocedural medical management, and a highly skilled neuroendovascular interventionalist are required in order to perform the procedure with an acceptable risk.     

Intracranial revascularization therapy: Angioplasty and stenting

Opinion statement Depending on the population studied, intracranial atherosclerosis accounts for 10% to 29% of ischemic brain events. A significant number of patients with intracranial atherosclerosis continue to suffer from repeated strokes or transient ischemic attacks despite optimal medical management. In selected patients, intracranial angioplasty with or without stenting is a promising treatment option. Patient selection, careful periprocedural medical management, and a highly skilled neuroendovascular interventionalist are required in order to perform the procedure with an acceptable risk.     

Extracranial revascularization therapy: Angioplasty and stenting

Opinion statement  Beginning with simple balloon angioplasty, minimally invasive revascularization techniques have progressed to the use of metallic stents for improved immediate and long-term results. Stent-supported angioplasty now offers a therapeutic option for those individuals ineligible for surgical revascularization of stenotic atherosclerotic lesions and who have failed maximal medical therapy. However, the clinical equivalence, or possibly even superiority, of angioplasty of the extracranial carotid and vertebral arteries in atheromatous occlusive disease over surgical revascularization has yet to be determined in ongoing randomized controlled trials. Additionally, endovascular techniques offer treatment for a variety of nonatherosclerotic disease affecting the extracranial arteries, such as inflammatory, radiation-induced, and postsurgical strictures; acute intimal dissection; traumatic and spontaneous arteriovenous fistulas; and aneurysms or pseudoaneurysms. For certain disease entities at high risk for surgical complications, endovascular procedures have gained preference as the therapeutic modality of choice, yet lacking controlled trials providing evidence for noninferiority against surgical approach. Continued innovation and refinement of endovascular technology and techniques will further improve technical success, reduce procedurerelated morbidity, and broaden the endovascular therapeutic spectrum for extracranial and intracranial cerebrovascular disease.     

Extracranial revascularization therapy: Angioplasty and stenting

Opinion statement Beginning with simple balloon angioplasty, minimally invasive revascularization techniques have progressed to the use of metallic stents for improved immediate and long-term results. Stent-supported angioplasty now offers a therapeutic option for those individuals ineligible for surgical revascularization of stenotic atherosclerotic lesions and who have failed maximal medical therapy. However, the clinical equivalence, or possibly even superiority, of angioplasty of the extracranial carotid and vertebral arteries in atheromatous occlusive disease over surgical revascularization has yet to be determined in ongoing randomized controlled trials. Additionally, endovascular techniques offer treatment for a variety of nonatherosclerotic disease affecting the extracranial arteries, such as inflammatory, radiation-induced, and postsurgical strictures; acute intimal dissection; traumatic and spontaneous arteriovenous fistulas; and aneurysms or pseudoaneurysms. For certain disease entities at high risk for surgical complications, endovascular procedures have gained preference as the therapeutic modality of choice, yet lacking controlled trials providing evidence for noninferiority against surgical approach. Continued innovation and refinement of endovascular technology and techniques will further improve technical success, reduce procedurerelated morbidity, and broaden the endovascular therapeutic spectrum for extracranial and intracranial cerebrovascular disease.     

Angioplasty with stenting for buttock claudication

We report the case of a patient presenting severe buttock claudication with normal neurologic and osteoarticular exams. He underwent a guidewire recanalization of his occluded superior gluteal artery followed by a percutaneous angioplasty with stenting, resulting in total relief of symptoms. This observation represents the first publication describing the use of a stent with recanalization of the gluteal artery. The technique seems promising for buttock pathology.