Intracranial angioplasty and stenting: long-term results from a single center

BACKGROUND AND PURPOSE: Large-vessel intracranial atherosclerotic stenosis carries a proved stroke risk of 8%-22% per year with "best medical therapy." The long-term clinical neurologic and angiographic outcomes of angioplasty and/or stent placement for intracranial atherosclerosis in a consecutive series of patients are presented. METHODS: The demographics, procedural details, procedural outcome, and long-term neurologic follow-up in 60 consecutive patients with 71 lesions, undergoing a total of 84 procedures, were analyzed. RESULTS: Angioplasty alone was performed in 62 procedures; 22 procedures involved stent placement. The periprocedural stroke+death rate was 4.8%. The overall complication-free success rate was 90.5%. Restenosis occurred in 23 lesions at a mean of 4.6 months; 13 were re-treated without complication. There were 4 strokes and 4 non-neurologic deaths during 224 patient-years of follow-up. The annualized stroke rate was 1.8%, and the annualized stroke+all-cause death rate was 3.0%. CONCLUSIONS: The stroke and death rates in this consecutive series of patients with severe intracranial atherosclerotic stenosis treated with optimal endovascular therapy are considerably less than those associated with the natural history of intracranial atherosclerosis treated with maximal medical therapy. Intracranial angioplasty with conditional stent placement is technically feasible and clinically effective with a substantial reduction in long-term stroke and death.     

Apollo stent for symptomatic atherosclerotic intracranial stenosis: study results

BACKGROUND AND PURPOSE: A recent trial shows an 8.3 per 100-patient-years' ischemic stroke rate in the territory of the intracranial stenotic artery, despite aspirin treatment. Our aim was to prospectively study the feasibility and outcome of a new intracranial balloon-expandable Apollo stent for symptomatic atherosclerotic intracranial stenosis (SAIS). MATERIALS AND METHODS: Forty-six patients (41 men and 5 women; median, 54 years of age) with forty-eight >or=50% SAISs were enrolled. Procedural feasibility was evaluated by stent success (residual stenosis or=24 months), which varied from 1 month to 30.7 months (median, 23.9 months). After 30 days, 1 patient (2.2%, 1/46) developed minor stroke in the target-lesion artery territory at 6.7 months. Primary end point rate was 4.3 per 100 patient years. Angiographic follow-up was performed in 25 patients. Seven restenoses (28%, 7/25) were detected, 1 of which was symptomatic. CONCLUSION: Angioplasty with the Apollo stent for symptomatic atherosclerotic intracranial stenosis is feasible. Severe tortuosity is an independent predictor of stent failure. Our clinical outcome seems to compare favorably with results of aspirin therapy, but the restenotic rate was high.     

Efficacy of treatment of severe carotid bifurcation stenosis by using self-expanding stents without deliberate use of angioplasty balloons

BACKGROUND AND PURPOSE: One of the limitations of carotid artery angioplasty is the potential for embolic stroke. Our purpose was to assess whether the force of a self-expanding stent alone is usually sufficient to dilate severely stenotic atherosclerotic plaques without the deliberate use of an angioplasty balloon. If so, the procedural stroke risk might be reduced. METHODS: Over a 30-month period, 21 consecutive patients were prospectively identified with severe symptomatic carotid artery stenosis (>70% NASCET [North American Symptomatic Carotid Endarterectomy Trial]) and relative indications for endovascular treatment. All underwent treatment with the aim of deploying a self-expanding stent across the stenosis without the use of angioplasty balloons or distal protection devices. RESULTS: Stent deployment was successful in 20/21 patients. In one patient, the stent could not be deployed without balloon predilatation and a stroke occurred. In the other 20 patients, angiography before and immediately after stent deployment showed a reduction in the mean stenosis from 83% to 49%. A second periprocedural stroke occurred as a result of early stent thrombosis at 4 days in a patient who stopped Acetylsalicylic acid while undergoing bowel preparation for colon surgery. He made a good recovery. Average duration of follow-up imaging was 19 months (range, 1-44 months). During the follow-up period there were four deaths, all unrelated to the carotid disease, and no major strokes. At 5-11 months, the average residual stenosis was 21%, which remained stable in 16 of the 18 patients studied between 12 and 44 months (average, 24 months). At last follow-up, in these 16 the mean peak systolic velocity was 123 cm/s (range, 60-238 cm/s) and the mean internal-to-common carotid ratio was 1.8. The other two patients were long-term failures of the "stent-only" approach. In one patient, a heavily calcified plaque prevented stent expansion and the artery occluded at 18 months with a minor stroke. In the second patient, a recurrent stenosis developed at 16 months with one episode of transient ischemic attack. CONCLUSION: Deployment of a self-expanding stent alone resulted in a favorable and more gradual reduction of severe symptomatic carotid stenosis. Improvements in stent profile and chronic outward force may widen the indications for simple stent placement without the use of balloons or adjunctive protection devices.     

腔内支架成形术治疗症状性颅内动脉狭窄

目的研究腔内支架成形术治疗症状性颅内动脉狭窄的安全性及有效性。方法对7例症状性颅内动脉狭窄的患者行腔内支架成形术治疗。结果7例患者中6例成功置入8枚冠脉支架,1例因支架置入困难仅行经皮腔内血管成形术(PTA),6例患者术后均未发生脑缺血发作,2例患者术后3～8个月复查经颅多普勒超声(TCD)血流通畅,未见内膜过度增生,1例单纯PTA患者术后症状明显改善,1例基底动脉支架成形术后出现动眼神经麻痹。结论腔内支架成形术是治疗症状性颅内动脉狭窄的安全、有效的方法,其长期疗效还需进一步随防研究。     

Stent fracture in revascularization for symptomatic ostial vertebral artery stenosis

Introduction We assessed the long-term follow-up examinations and complications of percutaneous transluminal angioplasty and stenting (PTAS) for symptomatic ostial vertebral artery (VA) stenosis. Methods A retrospective study was done to evaluate 12 patients with symptomatic ostial VA stenosis who underwent PTAS. Six patients were treated with the Palmaz stent and six with a balloon-expandable coronary stent. Initial angiographic follow-up examination was conducted about 12 months after PTAS in all patients. Simple radiographic, ultrasonographic and clinical follow-up examinations were scheduled every 6 months. Results Excellent dilatation was achieved in all patients without any procedural complications. Initial angiographic follow-up obtained at a mean of 13 months after PTAS detected no restenosis. However, an asymptomatic severe restenosis was detected at 24 months after PTAS in one patient (8%). During a mean follow-up of 31.5 months, three stent fractures were detected in deployed coronary stents (50%). None of the stent fractures was associated with either recurrent stroke or restenosis. No patients developed recurrent symptoms during the follow-up period. Conclusion PTAS for symptomatic ostial VA stenosis is effective in preventing recurrent stroke. As the open-cell single-joint type of stent is associated with the risk of fracture, long-term follow-up examinations including simple radiography are needed.     

Angioplasty and stenting in carotid dissection with or without associated pseudoaneurysm

BACKGROUND AND PURPOSE: Carotid angioplasty and stent placement may be the preferred treatment in patients with carotid dissection who have failed medical management. The goal of this study was to determine the procedural feasibility and safety as well as long-term complication rates of carotid angioplasty and stent placement in a consecutive cohort of relatively young, high-surgical-risk patients. PATIENTS AND TECHNIQUES: A series of 26 consecutive patients (mean age, 49 years; 15 men and 11 women) who underwent angioplasty and stent placement for carotid dissection with or without pseudoaneurysm from April 1997 to April 2005 at our institution (9 traumatic, 8 spontaneous, and 9 iatrogenic) was retrospectively reviewed. Twenty-eight stents were used in 29 procedures performed on 27 vessels (20 internal carotid arteries and 7 common carotid arteries). Patients were followed with cerebral angiography, CT, sonography, or clinically for a mean of 14.6 months (range, 5 days to 48.2 months) with 17 of 26 patients having at least 6 months of follow-up. Procedural and long-term complication rates were calculated. RESULTS: Dissection-induced stenosis was reduced from 71 +/- 18% to no significant stenosis in 20 of the 21 patients with measurable stenosis. The procedural transient ischemic attack (TIA) rate was 3 of 29 procedures (10.3%). There were no procedural strokes. One patient required angioplasty of a common femoral artery. One procedure was terminated when an asymptomatic new intimal flap was created before intervention. Two patients had occlusions of the treated vessel noted at 22 days (presented with contralateral stroke) and 3.4 months (asymptomatic). There were 2 unrelated deaths from myocardial infarction at 8 days and 15.2 months. Two patients had recurrent ipsilateral TIA at 2.7 months and 12 months. The 30-day occlusion and death rate was 2 of 29 procedures (6.9%). CONCLUSION: In this series, angioplasty and stent placement were effective in relieving stenosis secondary to carotid dissection with or without pseudoaneurysm and have low rates of ischemic complications.     

Carotid stenting without use of balloon angioplasty and distal protection devices: preliminary experience in 100 cases

BACKGROUND AND PURPOSE: A major concern during carotid artery stent placement is the potential for cerebral embolism. Diminishing the number of device manipulations across the lesion might reduce procedural stroke risk. For this purpose, we report our initial experience with carotid stent placement without the use of either balloon angioplasty or distal protection devices. MATERIALS AND METHODS: Eighty-seven consecutive patients with 100 carotid stenoses compose this series. Ninety four of the 100 hundred stented carotid arteries were either symptomatic (58 [58%]) or had a greater than 70% stenosis (36 [36%]). Six percent of them were asymptomatic and had stenosis between 50% and 70%. Patients underwent neurologic evaluation before the procedure and during follow-up at 1, 3, 6, and 12 months and annually thereafter. Carotid sonography and plain films of the neck were performed immediately after the procedure and then at the same time intervals. RESULTS: Primary stent placement was successful in 98 of 100 case subjects. In 2 case subjects, predilation was necessary before stent deployment. Neurologic periprocedural complications included 1 nondisabling and 1 disabling stroke and 5 transient ischemic attacks. The mean duration of follow-up was 23 months (range: 10-36 months). During the follow-up period, there were 5 deaths, all unrelated to the carotid disease, and no major stroke. The degree of stenosis decreased from a mean of 78.85% before the procedure to a mean of 21.23% immediately after. CONCLUSIONS: In this series, carotid stent placement without the use of either balloon angioplasty or distal protection devices was safe and effective with a low incidence of periprocedural complications.     

Recurrent symptomatic high-grade intracranial stenoses: safety and efficacy of undersized stents--initial experience

PURPOSE: To prospectively evaluate the safety and efficacy of undersized stents used in patients with high-grade intracranial stenosis and recurrent ischemic symptoms who are undergoing medical treatment. MATERIALS AND METHODS: In 18 patients (13 men, five women; age range, 51-82 years), 20 high-grade (>70%) intracranial stenoses were selected for stent placement. All patients had transient ischemic symptoms or minor strokes while undergoing combined antithrombotic therapy with acetylsalicylic acid plus clopidogrel or anticoagulation therapy with warfarin or heparin plus acetylsalicylic acid. Technical success was defined as reaching the target lesion and deploying a stent, with a residual stenosis of less than 50%. The diameter of the stent was 0.5-mm smaller than the measured diameter of the normal adjacent vessel to avoid dissection and vessel rupture. Primary endpoints for safety evaluation were the combined incidence of death or major or minor stroke at 30 days; for efficacy evaluation, the primary endpoint was the incidence of any stroke in the treated vascular territory within the first 6 months. Statistical evaluation of the reduction of stenosis was performed. RESULTS: In 18 of 20 stenoses, a stent was placed and the degree of stenosis was reduced from a median of 82% (range, 72%-97%) to a median of 16% (5%-40%; P <.001). The technical success rate was 90%. One patient had a parenchymal hemorrhage in a preexisting infarct on the 2nd day. Thus, the 30-day combined stroke and death rate was 6%. No immediate complication, thromboembolism, dissection compromising blood flow, or vessel rupture occurred during these procedures. Within the first 6 months after intervention, no patient had new ischemic symptoms in the treated vascular territory. CONCLUSION: In selected patients with recurrent ischemic events due to high-grade intracranial stenosis, undersized stent placement holds promise as an effective and safe procedure.     

血管内支架成形术治疗颅内动脉狭窄28例

目的探讨血管内支架成形术治疗颅内动脉狭窄的临床效果和安全性。方法 2006年7月—2010年12月,采用经皮血管内支架成形术治疗颅内狭窄28例。结果治疗狭窄颅内动脉28支,其中置入冠脉球扩式支架16枚,Wingspan支架6枚,apollo支架6枚,支架不能到位,放弃手术1例。27支动脉狭窄程度均明显改善,狭窄程度由原来的(89.36±5.63)%下降至(4.23±1.57)%,无死亡病倒,术后27例患者症状均明显改善,1例基底动脉重度狭窄患者术后出现一侧肢体麻木的并发症,1例术后出现脑栓塞表现,3 d后恢复正常,其他26例患者无并发症,随访2～12个月,无短暂性脑缺血发作(TIA)发作,随访患者经颅多普勒超声(TCD)结果显示,原狭窄血管近端、远端血流速度和支架置入后24 h的TCD结果无明显差别。结论血管内支架成形术是治疗症状性颅内动脉狭窄的安全、有效的方法,临床效果好,并发症少。适应证的正确选择、术中熟练的导管导丝技术和围术期的专业处理是手术成功的关键,但其远期疗效还需要长期随访。     

Analysis of periinterventional complications of intracranial angioplasty and stenting: A single center experience

Background and purposeTreatment of symptomatic intracranial atherosclerotic disease by angioplasty and stenting (PTAS) is limited by a high rate of periinterventional strokes. We performed a detailed analysis of these strokes at our center in order to identify strategies to reduce the risk of periinterventional complications.MethodsCase records and imaging data of 80 patients with a symptomatic 70–99% stenosis of a major intracranial artery treated with PTAS between July 2007 and December 2013 were reviewed. All patients had a sufficient response to aspirin and clopidogrel. Periinterventional strokes were categorized as either ischemic (perforator territory, distal embolic or delayed stent thrombosis) or hemorrhagic (intraparenchymal, subarachnoid).ResultsPeriinterventional complications occurred in 6/80 (7.5%) patients, consisting of 2 ischemic strokes (2.5%, both perforator territory), 3 hemorrhagic strokes (3.8%, 2 intraparenchymal due to reperfusion injury, 1 subarachnoid due to vessel rupture) and one death (1.3%) unrelated to stroke. All strokes occurred within 24 h after PTAS.ConclusionOur retrospective data analysis suggests that the risk of periinterventional stroke after PTAS of symptomatic intracranial atherosclerotic disease might be reduced by sufficient antiplatelet therapy and optimized management of patients with high risk for reperfusion injury or perforator strokes, including selection of a stenting device adapted to individual vessel morphology.     

Vertebral artery ostial stent placement for atherosclerotic stenosis in 72 consecutive patients: clinical outcomes and follow-up results

Introduction  The study’s purpose is to report the technical and clinical outcomes of a patient cohort that underwent vertebral artery ostium stent placement for atherosclerotic stenosis. Methods  We retrospectively analyzed a prospectively collected database of neurointerventional procedures performed at a single center from 1999 to 2005. Outcome measures included recurrent transient neurological deficits (TNDs), stroke, and death. Kaplan–Meier analysis was used to estimate stroke- and/or death-free survival at 12 months. Cox proportional hazard was used to identify risk factors for recurrent vertebrobasilar ischemic events. Results  Seventy-two patients with 77 treated vertebral ostial lesions were included. The 30-day stroke and/or death rate was 5.2% (n = 4), although no event was directly related to the vertebral ostium stent placement. Three procedure-related strokes were secondary to attempted stent placement at other sites (one carotid artery and two basilar arteries), and the one death was secondary to the presenting stroke severity. The mean clinical follow-up time available for 66 patients was 9 months. There were 14 TNDs (21%), two strokes (3%), and two deaths (3%) recorded in the follow-up. Recurrent vertebrobasilar ischemic events occurred in nine patients (seven TNDs and two strokes). No recurrent stroke and/or deaths were related to the treated vertebral ostium. Stroke- and/or death-free survival rate (including periprocedural stroke and/or death) was 89 ± 5% at 12 months. No vascular risk factor was significantly associated with recurrent vertebrobasilar ischemic events. Conclusions  Vertebral artery ostium stent placement can be safely and effectively performed with a low rate of recurrent stroke in the territory of the treated vessel. Patients who also underwent attempted treatment of a tandem intracranial stenosis appeared to be at highest risk for periprocedure stroke.     

Endovascular therapy of symptomatic intracranial stenosis in patients with impaired regional cerebral blood flow or failure of medical therapy

BACKGROUND AND PURPOSE:Symptomatic intracranial stenoses have a high risk for a recurrent stroke if treated medically. Although angioplasty and stent placement are proposed treatment options, data on longer-term outcome are limited.Materials and METHODS:We analyzed all endovascular procedures on symptomatic intracranial stenosis at our institution from January 1998 to December 2005. We retrospectively assigned patients to group A (symptoms despite antithrombotic therapy) or group B (impaired regional cerebral blood flow [rCBF]). Primary outcome events were periprocedural major complications or recurrent ischemic strokes in the territory of the treated artery. We used the Kaplan-Meier method to calculate survival probabilities.RESULTS:The procedural technical success rate was 92% (35/38) with periprocedural major complications in 4 cases (10.5%; group A [8.3%, 2/24], group B [14.3%, 2/14]). Median (range) follow-up for the 33 patients with technically successful procedures was 21 (0–72) months. Recurrent ischemic strokes occurred in 15% (3/20) of patients in group A and 0% (0/13) of patients in group B. Overall, there were 21% (7/33) primary outcome events (group A [25%, 5/20], group B [15%, 2/13]). There was a nonsignificant trend for better longer-term survival free of a major complication or recurrent stroke in patients with impaired rCBF compared with patients who were refractory to medical therapy treatment (Kaplan-Meier estimate 0.85 [SE 0.10] vs 0.72 [SE 0.11] at 2 years, respectively).CONCLUSION:Interventional treatment of symptomatic intracranial stenosis carries significant risk for complications and recurrent stroke in high-risk patients. The observation that patients with impaired rCBF may have greater longer-term benefit than medically refractory deserves further study.

Atherosclerotic stenosis of the major intracranial arteries accounts for 8%–10% of all ischemic strokes^{1, 2} and, after a symptomatic event, the annual risk of recurrence is high (estimates, 8%–11%).^3–5 However, the optimum strategy for secondary prevention in this situation remains uncertain. In particular, the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) study failed to show a benefit of warfarin compared with aspirin in the prevention of recurrent ischemic events.⁴Interventional procedures such as percutaneous transluminal angioplasty (PTA) and stent placement have been proposed as potentially more effective methods of secondary prevention. Two groups of patients are frequently considered as potential target groups for endovascular therapy. First, patients who have recurrent ischemic events despite standard medical therapy and second (and more recently), patients with clinically apparent impaired regional cerebral blood flow (rCBF) secondary to the stenoses.^6–9 Both groups are considered to be at especially high risk for stroke, which justifies the use of a potentially risky procedure. However, the acute risks and long-term outcome of such endovascular therapies in both subgroups are still poorly described.The purpose of this study, therefore, was to report our experience with angioplasty and stent placement for symptomatic intracranial atherosclerotic stenoses in patients who have either failed medical therapy or who have impaired rCBF secondary to intracranial stenoses.     

Primary stent placement for infrarenal aortic stenosis: immediate and midterm results

PURPOSE: To evaluate the safety and the long-term clinical and hemodynamic results of primary stent placement of atherosclerotic calcified stenosis of the infrarenal aorta. MATERIAL AND METHODS: Between July 1996 and July 1999, 15 patients (nine male, si- female; mean age, 53.9 years) with symptomatic, calcified aortic stenosis were treated with primary stent placement. Patients underwent abdominal aortography and bilateral lower extremity arteriography. Follow-up was performed in all 15 patients. Technical success was defined as residual stenosis of less than 30% or a resting trans-systolic pressure gradient of less than 10 mm Hg after stent placement. Clinical patency was defined as the absence or improvement of symptoms after stent placement. Hemodynamic patency was defined as a normal triphasic Doppler waveform in the common femoral artery, an ankle-brachial index greater than 0.90, or the absence of a thigh-brachial pressure gradient at rest in either limb. RESULTS: Technical success was achieved in 13 of 15 patients. The two patients considered to be technical failures had resting trans-systolic pressure gradients of 12 and 13 mm Hg, respectively, after stent placement. After the mean follow-up of 36 months, primary clinical and hemodynamic patency rates were 85% and the secondary hemodynamic patency rate was 100%. Two of five symptomatic recurrences during the 36-month follow-up period (range, 12-46 months) were a result of aortic restenosis and were treated with repeated percutaneous transluminal angioplasty. None of the patients required aortic surgery. Complications of the primary procedure included one puncture site infection, one pseudoaneurysm, and one distal embolization, which delayed discharge of three patients. There was no morbidity during the secondary interventions. CONCLUSION: Primary stent placement as treatment of calcified infrarenal aortic stenosis proved to be safe and also provided durable long-term clinical improvement.     

症状性颅内动脉粥样硬化性狭窄的Wingspan支架成形术

目的 评价Gateway-Wingspan球囊支架系统治疗症状性颅内动脉粥样硬化性狭窄的安全性、可行性及近期疗效.方法 应用Gateway-Wingspan球囊支架系统治疗17例症状性颅内动脉狭窄患者,观察支架置入前后症状、狭窄率改善、手术成功率及并发症发生情况,术后平均随访5个月.结果 17处病变,其中位于颈内动脉颅内段5处,大脑中动脉5处,椎动脉颅内段4处,基底动脉3处.16处病变经Gateway球囊预扩张后支架成功准确释放.1例因Gateway球囊无法到达靶病变,支架直接定位后释放.支架成功率100%.治疗前平均狭窄率为82%,治疗后残余平均狭窄率为43%.术后平均随访5个月,4例一过性缺血发作(TIA)患者未再次发作;12例卒中患者症状均有明显改善.1例发生并发症,考虑为对侧半球梗死.未发生出血性并发症.结论 采用Gateway-Wingspan球囊支架系统治疗颅内动脉粥样硬化性狭窄有良好的安全性与短期疗效.     

Treatment of symptomatic high-grade intracranial stenoses with the balloon-expandable Pharos stent: initial experience

INTRODUCTION: We report our first clinical experience with a CE-marked flexible monorail balloon-expandable stent for treatment of high-grade intracranial stenoses. METHODS: Between April 2006 and November 2007 21 patients with symptomatic intracranial stenoses (>70%) were treated with the PHAROS stent. In seven patients, the procedure was performed during acute stroke intervention. Procedural success, clinical complication rates and mid-term follow-up data were prospectively recorded. RESULTS: During a median follow-up period of 7.3 months one additional patient died of an unknown cause 3 months after the intervention. A patient with a significant residual stenosis presented with a new stroke after further progression of the residual stenosis. None of the successfully treated patients experienced ipsilateral stroke. CONCLUSION: Recanalization of intracranial stenoses with the balloon-expandable Pharos stent is technically feasible. The periprocedural complication rate and mid-term follow-up results were in the range of previously reported case series. This pilot study was limited by the small sample size and severe morbidity of the included patients. Final evaluation of the efficacy of Pharos stent treatment demands further investigation.     

Primary endovascular stent placement for focal infrarenal aortic stenosis: long-term results

PURPOSE: The objectives of this retrospective study were to determine the technical success, safety, and long-term results of primary stent implantation in infrarenal aortic stenosis. MATERIALS AND METHODS: A total of eight atherosclerotic stenoses and one occlusion of the infrarenal aorta (ie, midaortic syndrome) were treated with endoluminal stent placement after balloon angioplasty. Aortoiliac lesions were excluded. Technical success and patency were assessed. RESULTS: Primary technical success in percutaneous transluminal angioplasty and subsequent stent placement was achieved in all patients. No complications occurred, and no morbidity was encountered. Primary clinical patency rates were 100% on all follow-up examinations. Long-term results with a mean follow-up of 110 months (range, 99-117 months) were recorded in seven patients; one patient had died and one was lost to follow-up. CONCLUSIONS: In view of the excellent initial results and promising long-term follow-up data in a small series, stent placement after predilation in properly selected patients with isolated infrarenal aortic stenosis appears to be a promising, durable treatment. It should be considered as a primary method of treatment.     

Stent-assisted angioplasty of symptomatic intracranial vertebrobasilar artery stenosis: feasibility and follow-up results

BACKGROUND AND PURPOSE: The natural history of symptomatic, untreated posterior circulation stenosis is dismal, with many patients experiencing significant morbidity or mortality. The purpose of this study was to evaluate the feasibility and results of stent-assisted angioplasty of symptomatic intracranial vertebrobasilar artery stenosis.METHODS: We reviewed the imaging findings and medical records of 17 consecutive patients who were treated with stent-assisted angioplasty for medically refractory vertebrobasilar artery stenosis. The location of the lesion, degree of stenosis, procedure-related complications, and clinical and short- and long-term angiographic results were assessed.RESULTS: The population included 17 cases (10 men, seven women; age range, 51–74 years; mean, 64 years). The locations of the lesions were intracranial vertebral artery (n = 13) and basilar artery (n = 6). The mean degree of stenosis decreased from 76.1 ± 14.6% before stent-assisted angioplasty to 1.3 ± 2.8% (P < .05) after the procedure. Acute in-stent thrombosis developed in one case (6%, Mori type B lesion), which was successfully treated with intraarterial abciximab infusion and angioplasty. Another patient (6%, Mori type C lesion) developed immediate postprocedural transient diplopia and ataxia, which gradually resolved. No other patient showed symptoms related to the vertebrobasilar artery lesion at follow-up. No significant restenosis was observed at short-term (five patients; follow-up range, 0.5–6 months; mean, 4.3 months) or long-term (six patients; follow-up range, 12–41 months; mean, 21 months) angiographic follow-up.CONCLUSION: Stent-assisted angioplasty is a feasible treatment method for vertebrobasilar artery stenosis. The patency of the stent-assisted angioplasty seems to be preserved in the long-term, with good clinical outcome.

The natural history of untreated posterior circulation stenosis is dismal, with many patients experiencing significant morbidity or mortality (1–3). Retrospective data suggest that the annual stroke rates for patients with symptomatic intracranial vertebral or basilar artery stenosis are 7.8% and 10.7%, respectively, despite anticoagulation or antiplatelet therapy (3).Recently, percutaneous transluminal angioplasty was proposed as a promising alternative treatment for patients with intracranial atherosclerotic stenosis symptoms despite medical therapy. However, percutaneous transluminal angioplasty has had the problems of dissection, elastic recoil, and thrombosis (4, 5). In a series of 42 cases of angioplasty for intracranial stenosis by Mori et al (4), the 1-year angiographic restenosis rate in type A (short, ≤5 mm in length, concentric or moderately eccentric lesions not totally occlusive), type B (tubular, 5–10 mm in length, extremely eccentric or totally occluded lesions, <3 months old), and type C (diffuse, >10 mm in length, extremely angulated [>90°] lesions with excessive tortuosity of the proximal segment, or totally occluded lesions, and ≥3 months old) lesions were 0%, 33%, and 100%, respectively, with cumulative risk of fatal or nonfatal ipsilateral ischemic stroke in 8%, 12%, 56%, respectively, at 1 and 2 years.Stent-assisted angioplasty has been limited mainly by the apprehension concerning the technical feasibility, periprocedural complications, and short- and long-term outcomes (6). Major problems still exist; nonetheless, recent technical advances in instruments used for angioplasty and stent placement have allowed easier trackability through the small and tortuous intracranial vessels. Also, experience from the earlier works of intracranial angioplasty and stent placement has allowed a relatively safe procedure with fewer periprocedural complications (7–14).We reviewed our experience with stent-assisted angioplasty for medically refractory intracranial vertebral and basilar artery stenoses, including the intra- and periprocedural complications and long-term angiographic and clinical outcomes.     

Incidence and Clinical Significance of Acute Reocclusion after Emergent Angioplasty or Stenting for Underlying Intracranial Stenosis in Patients with Acute Stroke

BACKGROUND AND PURPOSE:A major concern after emergent intracranial angioplasty in cases of acute stroke with underlying intracranial stenosis is the acute reocclusion of the treated arteries. This study reports the incidence and clinical outcomes of acute reocclusion of arteries following emergent intracranial angioplasty with or without stent placement for the management of patients with acute stroke with underlying intracranial atherosclerotic stenosis.MATERIALS AND METHODS:Forty-six patients with acute stroke received emergent intracranial angioplasty with or without stent placement for intracranial atherosclerotic stenosis and underwent follow-up head CTA. Acute reocclusion was defined as “hypoattenuation” within an arterial segment with discrete discontinuation of the arterial contrast column, both proximal and distal to the hypoattenuated lesion, on CTA performed before discharge. Angioplasty was defined as “suboptimal” if a residual stenosis of ≥50% was detected on the postprocedural angiography. Clinical and radiologic data of patients with and without reocclusion were compared.RESULTS:Of the 46 patients, 29 and 17 underwent angioplasty with and without stent placement, respectively. Acute reocclusion was observed in 6 patients (13%) and was more frequent among those with suboptimal angioplasty than among those without it (71.4% versus 2.6%, P < .001). The relative risk of acute reocclusion in patients with suboptimal angioplasty was 27.857 (95% confidence interval, 3.806–203.911). Furthermore, a good outcome was significantly less frequent in patients with acute reocclusion than in those without it (16.7% versus 67.5%, P = .028).CONCLUSIONS:Acute reocclusion of treated arteries was common after emergent intracranial angioplasty with or without stent placement in patients with acute stroke with intracranial atherosclerotic stenosis and was associated with a poor outcome. Suboptimal results of angioplasty appear to be associated with acute reocclusion, irrespective of whether stent placement was performed.

Intracranial atherosclerotic stenosis (ICAS) is rapidly becoming a major concern worldwide in patients with stroke because Asian, Hispanic, and African populations, which are prone to ICAS, constitute an overwhelming majority of the population of the world.¹ Acute stroke caused by an in situ thrombosis at the site of ICAS differs from that caused by cardiogenic embolic occlusion and may not respond to modern mechanical embolectomy procedures such as stent-retriever embolectomy or manual aspiration embolectomy. Few studies have been published hitherto on the optimal treatment plan for patients with acute stroke with underlying ICAS.^2–5 Emergent intracranial angioplasty, with or without stent placement, has been recently suggested as an effective treatment option for the management of underlying ICAS following mechanical embolectomy; for example, Yoon et al⁴ reported a successful revascularization rate of 95% and a favorable outcome rate of 65% with this strategy.Nevertheless, a major concern after emergent intracranial angioplasty in cases of acute stroke is the acute reocclusion of the treated arteries. Acute reocclusion may occur following intracranial angioplasty or stent placement as a result of platelet activation, adherence, and aggregation triggered by the disruption of vulnerable plaque and endothelial damage; unsuccessful or inadequate pretreatment with antiplatelet drugs; dissection; or vasospasm.⁶ Despite the possibility of this complication in patients with acute stroke, data regarding its incidence and clinical consequences have not yet been reported in literature, to our knowledge.Thus, this study aimed to investigate the incidence and clinical outcomes of arterial reocclusion in patients with acute stroke undergoing emergent angioplasty with or without stent placement following stent-retriever embolectomy. Additionally, we sought to determine the risk factors associated with acute reocclusion in these patients.     

Preliminary results of endovascular stent-assisted angioplasty for symptomatic middle cerebral artery stenosis

BACKGROUND AND PURPOSE: Stent placement for intracranial atherosclerosis has become an alternative treatment technique; however, stent placement for middle cerebral artery (MCA) stenosis remains a technical and clinical challenge. Our purpose was to assess the feasibility, safety, and effectiveness of stent placement for MCA stenosis. METHODS: Between May 1998 and August 2003, we performed stent placement for MCA stenosis (more than 50%) in 17 patients and retrospectively analyzed the technical success rate, complications, and outcomes over 10 months. RESULTS: Stent placement was technically successful in 16 (94.1%) patients and failed in one patient (5.9%), because the stent did not reach the lesion due to carotid artery tortuousity. In 16 patients, postprocedural angiography showed restoration of the normal luminal diameter. Acute in-stent thromboses occurred in nine patients (56.3%) and was lysed with abciximab. The parent artery ruptured in two patients (12.5%): One died from massive subarachnoid hemorrhage, and the other patient received a second stent over the tear site. Stent jumping (distal migration at the time of balloon inflation) occurred in one patient (6.3%) and was solved by implanting a second stent. Periprocedural complications included subacute in-stent thrombosis (n = 1, 6.3%) and minor stroke (n=1, 6.3%); these were relieved with heparin therapy or local thrombolysis. Fifteen patients experienced symptomatic relief or were stable at follow-up. Angiographic follow-up (n=6) revealed no in-stent restenosis. CONCLUSION: Stent placement for symptomatic MCA stenosis was technically feasible and effective in alleviating symptoms and improving cerebral blood flow.     

Outcomes of carotid angioplasty and stenting for radiation-associated stenosis

BACKGROUND AND PURPOSE: In light of their high surgical risk, carotid angioplasty and stent placement may be preferred in patients with radiation-associated carotid stenosis. The purpose of this study was to determine the procedural complication rate, patency, and clinical outcomes after carotid angioplasty and stent placement in this small group of high-risk patients. METHODS: Sixteen patients (mean age, 65 years; 5 women and 11 men) who received radiation therapy for head and/or neck malignancy subsequently developed carotid stenosis (mean, 84%; range, 70%-99%) in a total of 19 carotid arteries, which were treated with angioplasty and stent placement. The patients were followed for a mean time of 28 months (range, 5-78 months) with periodic Doppler studies, angiography, CT angiography, or clinically. RESULTS: In the total 19 stented carotid arteries, 23 procedures were performed (22 stent placement procedures and one repeat angioplasty). The procedural stroke rate was 1/23 (4%). The procedural transient ischemic attack rate was 0/23 (0%). There was one other observed complication: a puncture site hematoma. The 30-day postprocedure complication rate was 0/23 (0%); no neurologic symptoms were reported. Fifteen of the 19 vessels (79%) developed no new stenosis throughout the follow-up period. Two of 19 (11%) vessels had repeat angioplasty and stent placement; 1/19 (5%) had a repeat angioplasty. One restented vessel has remained patent for 50 months. Another restented vessel required a third stent placement 17 months after the second. Two of 19 (11%) vessels occluded per Doppler examination 14 and 22 months postprocedure. CONCLUSION: Angioplasty and stent placement have low rates of complications and restenosis in the treatment of radiation-associated carotid occlusive disease.