带髂内分支支架的腔内隔绝术治疗腹主动脉瘤伴双髂动脉瘤

目的探讨带髂内分支支架的腔内隔绝技术在腹主动脉瘤伴双髂动脉瘤治疗中的应用。方法回顾性分析2011年6月～2012年6月我院收治的10例腹主动脉瘤合并双髂动脉瘤患者的临床资料。患者均于术前行CT血管造影(CTA)检查,腹主动脉瘤均为肾下型;髂动脉瘤仅累及髂总动脉8例,累及髂内动脉开口处2例。手术先置入带髂内分支的髂动脉带膜支架,再置入腹主动脉瘤的分叉型带膜支架。结果患者均一次手术成功,无死亡。9例患者获得随访,随访时间3～6个月,患者腹部搏动性肿块均消失,均未出现臀部、骶尾部坏死,无明显性功能障碍,1例出现臀部的轻度间歇性跛行。8例术后3个月行腹主、双髂动脉彩超检查,未见明显内瘘,移植的髂内分支支架血流通畅。3例术后6个月行腹主、双髂动脉CTA检查,未见Ⅰ型、Ⅲ型内瘘,髂内分支支架内血流通畅。结论带髂内分支支架的腔内隔绝技术在腹主动脉瘤伴双髂动脉瘤的治疗中是安全、有效的;可以有效地保留一侧髂内动脉,减少或避免因髂内动脉封闭而带来的并发症。     

“烟囱”技术在Ⅲ型夹层动脉瘤和腹主动脉瘤腔内修复术中的应用

目的 总结“烟囱”技术在主动脉瘤腔内修复术中的应用体会和一期效果.方法 在30例主动脉瘤腔内修复术中使用“烟囱”技术增加近端覆膜支架锚定区,其中25例DebakeyⅢ型夹层动脉瘤使用“烟囱”支架保留左锁骨下动脉(23例)或左颈总动脉(3例),肾下腹主动脉瘤使用“烟囱”支架保留肾动脉(5例).结果 所有病例均顺利完成操作,放置“烟囱”支架的分支动脉术中造影均通畅.其中2例夹层动脉瘤(8％)和1例腹主动脉瘤残留(20％)少量Ⅰ型内漏,1例夹层动脉瘤左锁骨下动脉“烟囱”病例术后5d猝死,考虑为远侧破口所致夹层动脉瘤破裂.其余22例夹层动脉瘤和4例肾下腹主动脉瘤均无内漏.随访28例(90.3％),随访1～19个月,平均(6±5)个月.随访期超声或CTA示“烟囱”血管血流均通畅.1例腹主动脉瘤仍有内漏,2例夹层内漏病例随访中(尚未行CTA),其他病例瘤腔血栓形成.结论 “烟囱”技术能够有效的延长覆膜支架在主动脉瘤腔内修复术中的近端锚定区并保持重要分支动脉通畅.     

复杂腹主动脉瘤内脏分支重建技术评价

随着腔内治疗技术和器材的发展,腹主动脉瘤腔内修复术已成为腹主动脉瘤的首选治疗方式。而近端锚定区不良以及累及内脏分支的复杂腹主动脉瘤则是制约该技术发展和影响其治疗效果的关键因素。平行支架、开窗支架、分支支架、多层密网支架和去分支等技术是目前重建内脏分支的主要方法,笔者结合相关研究结果对上述技术进行简要讨论,以期为复杂腹主动脉瘤的腔内治疗提供参考。     

高危复杂腹主动脉瘤腔内修复术临床分析

目的 评估应用多种腔内技术治疗高危复杂腹主动脉瘤的可行性.方法 2001年1月至2010年12月,共138例腹主动脉瘤患者接受腹主动脉腔内修复术(EVAR),其中9例患者为高危复杂性腹主动脉瘤.男性8例,女性1例,年龄26～87岁,平均67岁.其中2例近肾腹主动脉假性动脉瘤,5例近肾腹主动脉瘤,1例腹主动脉瘤合并双髂总动脉瘤及左侧髂内动脉瘤,1例EVAR术后右髂内动脉瘤.所采用的腔内技术包括:主动脉支架开窗技术和扇形技术2例,烟囱技术5例,球囊辅助下髂内动脉瘤腔内治疗1例和球囊辅助反转支架技术1例.结果 所有腔内技术均获得成功.术中支架释放后即刻发现内漏4例,其中1例患者为Ⅰ型和Ⅲ型内漏,经大动脉球囊扩张后内漏消失;2例Ⅰ型内漏,其中1例行弹簧栓栓塞成功,另1例行近端裸支架成功.1例Ⅱ型内漏,经随访瘤腔直径未增大,未处理.随访4～79个月,平均25.9个月.无动脉瘤破裂,动脉瘤瘤体直径均有不同程度的缩小.随访过程中7例患者的靶血管(肾动脉、肠系膜上动脉和髂内动脉)均保持通畅.1例髂内动脉重建支架术后18个月血栓形成,但无盆腔缺血等症状.结论 对于不能耐受手术的高危复杂腹主动脉瘤患者,选择合适的腔内技术可以增加EVAR术的成功率,近、中期效果满意.     

血管外科技术创新的意义与趋势

血管外科的发展与技术的创新发展密切相关。血管外科治疗范围主要包括主动脉疾病、外周动脉疾病及静脉疾病,近年的治疗方法已明显侧重于血管腔内治疗技术,且随着技术的不断创新发展,既往以开放手术治疗为主的许多复杂疑难病例,如累及升主动脉、主动脉弓的主动脉夹层或瘤样扩张疾病,近肾或累及肾动脉等重要内脏动脉分支的腹主动脉瘤等,亦逐渐采用开窗支架、分支支架等新型血管腔内技术治疗,未来内脏动脉及主动脉弓上重要分支动脉的腔内重建将成为血管腔内技术发展的主要方向。外周动脉病变的血管腔内治疗方法与治疗理念均处于改进阶段,各新型开通装置增加了血管腔内治疗成功率,涂药球囊和减容装置较传统支架置入术的远期效果有明显优势,同时能达到不遗留异物的目的,但现阶段还不能完全取代支架置入术。     

复杂腹主动脉瘤腔内修复65例经验北大核心CSCD

目的探讨复杂肾下腹主动脉瘤腔内治疗的结果。方法回顾性分析2006年1月~2013年3月65例复杂肾下腹主动脉瘤腔内治疗的资料。其中腹主动脉瘤颈过短（〈2 cm）15例（23.1%）,参照肾动脉将支架向腹主动脉近侧释放;瘤颈严重成角（≥60°）28例（43.1%）,将腹主动脉拉直再释放支架;同时具有短瘤颈和严重成角10例（15.4%）;涉及双髂总动脉瘤的保留髂内动脉的处理5例（7.7%）,尽量保留一侧髂内动脉以防盆腔脏器缺血,2例分期行髂内动脉覆盖;入路动脉狭窄或者闭塞导致腔内覆膜支架的输送器到达预定位置困难5例（7.7%）;合并其他特殊病变2例（3.1%）。均采用腔内覆膜支架修复,其中进口血管支架29例（44.6%）,国产血管支架36例（55.4%）。结果手术均成功。23例（35.4%）即时内漏,其中Ⅰ型6例,Ⅱ型14例,Ⅲ型3例。无手术死亡。术后住院时间7~15 d,平均8.2 d。随访60例（92.3%）,随访时间1~8年,平均3.5年。死亡5例（8.3%）,死亡原因均与该病无关。1例半年后支架移位,内漏,再次行腔内修复,置延长段支架后内漏消失,继续随访22个月,支架形态和位置良好,无支架移位和内漏发生。其他内漏均消失。左下肢缺血3例,原因为1例左侧髂分支支架移位导致闭塞,行股-股动脉耻骨上人工血管旁路移植后下肢缺血症状缓解,2例髂动脉打折,再次腔内治疗放置裸支架后缺血症状缓解。结论随着腔内技术的发展和腔内治疗器材的不断完善,过去认为不能采用腔内治疗的复杂腹主动脉瘤也可以采用腔内治疗,对于复杂肾下腹主动脉瘤,腔内治疗可以获得较为满意的中远期疗效。     

腹主动脉瘤合并左髂总动脉纤细行腔内修复1例北大核心CSCD

血管腔内动脉瘤修复术(endovascular aneurysm repair,EVAR)已广泛应用于腹主动脉瘤(abdominal aortic aneurysm,AAA)的治疗,微创,安全,即使高危患者也可实施。然而,高达40%的患者因为瘤颈解剖、内脏动脉或血管通路问题不适合行标准EVAR手术[1,2]。2020年我们采用自制髂内动脉分支支架重建髂内动脉1例[3]。2021年7月,我院对1例腹主动脉瘤合并左髂总动脉纤细患者采用术中自制带左髂总动脉分支支架的覆膜支架行腔内治疗,报道如下。     

腹主动脉瘤腔内隔绝术后内漏

腹主动脉瘤腔内隔绝术后内漏 (ｅｎｄｏｌｅａｋ)是腹主动脉瘤腔内治疗过程中所产生的并发症[1] 。腔内治疗的方法是在腹主动脉瘤腔内放置带膜的血管支架 ,用移植物将循环血流和动脉瘤囊相隔开 ,使动脉瘤不再承受到循环血流的冲击 ,不再承受动脉压的压力 ,腹主动脉瘤不再增大和破裂。如果经过腔内隔绝术后 ,移植物外层的动脉瘤囊内仍有循环血流进入或进出 ,说明动脉瘤未与循环系统完全隔开 ,动脉瘤继续扩大甚至发生破裂 ,导致腹主动脉瘤隔绝手术的失败[2 ,3] 。所有类型移植物的内漏率是 2 4% (12 4/ 5 2 3) ,即发性内漏率约为 17% (89/ 5 2…     

应用G-iliac?髂动脉分支支架治疗髂总动脉瘤的临床应用分析

目的分析应用G-iliac?髂动脉分支支架治疗髂总动脉瘤的安全性和有效性。方法回顾性分析2021年6月—2022年6月于首都医科大学附属北京友谊医院血管外科应用G-iliac?髂动脉分支支架治疗并保留髂内动脉(IIA)的7例髂总动脉瘤患者的临床资料, 分析手术效果及相关并发症发生情况。结果 7例患者均为男性, 年龄57～80岁, 平均70.9岁。腹主动脉瘤合并髂总动脉瘤6例, 单纯髂总动脉瘤1例, 均成功应用G-iliac?髂动脉分支支架保留IIA。术后1例患者出现心源性休克。7例患者随访时间为3～15个月, 平均8个月。随访期间, 髂动脉及IIA支架均通畅, 无髂动脉分支支架相关内漏发生, 无支架移位, 无臀肌跛行, 无性功能障碍症状, 无主动脉相关死亡。腹主动脉瘤最大径及髂总动脉瘤最大径均稳定。结论对于髂总动脉瘤患者, 通过G-iliac?髂动脉分支支架保留IIA是一种安全、有效的技术。其技术成功率和IIA通畅率高, 并发症发生率低, 但长期效果仍需更多的患者及更长时间的随访数据支持。     

腹主动脉瘤腔内治疗的实验研究

目的　探讨腹主动脉瘤的腔内血管外科治疗方法。方法　将健康杂种犬 9只通过剖腹手术建立 4个肾动脉平面以下的腹主动脉瘤模型 (Ⅰ组 ) ,5个肾动脉平面以上的腹主动脉瘤模型 (Ⅱ组 ) ,然后经髂动脉给Ⅰ组置入支架型人工血管隔绝其腹主动脉瘤 ,对Ⅱ组则先重建双侧肾动脉和肠系膜上动脉的血流 ,然后再自髂动脉置入支架型人工血管 ,隔绝瘤体。术后观察血管通畅情况及动物存活情况 ,2 ,3个月后处死动物 ,检查支架型人工血管通畅及血管内皮生长情况。结果　腹主动脉瘤成模率为 10 0 % ,术后Ⅰ组 4只犬成活良好 ;Ⅱ组中 1只成活良好 ,另 4只分别于术后 4h ,1d ,3d ,4d后死亡。 2 ,3个月后处死动物 ,解剖发现支架型人工血管通畅 ,主动脉瘤体萎缩 ,光镜和电镜检查显示支架内及支架两端血管内皮生长良好。结论　腔内血管外科技术能有效地治疗主动脉瘤 ,特别是为肾动脉平面以上的主动脉瘤的治疗提供了一种新的方法。     

Computational fluid dynamics analysis of intracranial aneurysms treated with flow diverters: A case report

IntroductionIntracranial aneurysms (IAs) are localized dilatations of intracranial arteries due to weaknesses of the endothelial layer. IAs may be treated by flow diverters (FDs), alternatively to stents and coils combination. FD is a method for the treatment of IAs especially for large, wide-necked or fusiform aneurysms. In this case report, we described a 65-year-old woman with IA who were treated by FD.Case presentationA 65-year-old woman was diagnosed with a giant aneurysm at the posterior inferior cerebellar artery segment of the left internal carotid artery. Then based on the computed tomography data of this woman, aneurysm vascular stent model was constructed before and after FD, and internal pressure, velocity, wall shear stress (WSS) of aneurysms were determined by CFD analysis. Standard boundary conditions were applied. It was found that a single FD stent and double FD stents decreased the blood flow and WSS of aneurysm. The effect of single FD stent + 30% filling on blood flow was more obvious, but the aneurysm rupture was caused by excessive coil packing. So, a single stent + 10% coil packing rate was the best option for treating aneurysms.ConclusionsCFD analysis for flow velocity and WSS have protection on aneurysms.     

Double-barrel technique for preservation of aortic arch branches during thoracic endovascular aortic repair

Thoracic endovascular aortic repair (TEVAR) may involve either planned or inadvertent coverage of aortic branch vessels when stent grafts are implanted into the aortic arch. Vital branch vessels may be preserved by surgical debranching techniques or by placement of additional stents to maintain vessel patency. We report our experience with a double-barrel stent technique used to maintain aortic arch branch vessel patency during TEVAR. Seven patients underwent TEVAR using the double-barrel technique, with placement of branch stents into the innominate (n = 3), left common carotid (n = 3), and left subclavian (n = 1) arteries alongside an aortic stent graft. Gore TAG endografts were used in all cases, and either self-expanding stents (n = 6) or balloon-expandable (n = 1) stents were utilized to maintain patency of the arch branch vessels. In three cases the double-barrel stent technique was used to restore patency of an inadvertently covered left common carotid artery. Four planned cases involved endograft deployment proximally into the ascending aorta with placement of an innominate artery stent (n = 3) and coverage of the left subclavian artery with placement of a subclavian artery stent (n = 1). TEVAR using a double-barrel stent was technically successful with maintenance of branch vessel patency and absence of type I endoleak in all seven cases. One case of zone 0 endograft placement with an innominate stent was complicated by a left hemispheric stroke that was attributed to a technical problem with the carotid-carotid bypass. On follow-up of 2-18 months, all double-barrel branch stents and aortic endografts remained patent without endoleak, migration, or loss of device integrity. The double-barrel stent technique maintains aortic branch patency and provides additional stent-graft fixation length during TEVAR to treat aneurysms involving the aortic arch. Moreover, the technique uses commercially available devices and permits complete aortic arch coverage (zone 0) without a sternotomy. Although initial outcomes are encouraging, long-term durability remains unknown.     

Feasibility and possibility of Inoue stent graft for thoracic aortic aneurysms

Open surgical repair is a traditional treatment for patients with thoracic aortic aneurysms. Despite recent advances in surgical techniques and anesthetic management, the surgical repair of thoracic aortic aneurysms is still associated with significant mortality and morbidity. Endovascular aneurysm repair of thoracic aortic aneurysms is emerging as an alternative method for repair in selected patients. Although endovascular stent grafting is less invasive than open surgical repair, involvement of branch vessels and precipitous curvature of the aortic arch limits the application of stent grafting. Inoue stent graft system consists of soft nitinol ring-type stent which enables very flexible stent graft, and it can well comply with the precipitous curvature of the aortic arch. The system also provides a stent graft with a side branch to manage the left subclavian artery. This system does not require the surgical revascularization of the left subclavian artery. In this report, we show the feasibility and possibility of Inoue stent graft system to manage the aortic arch aneurysm.     

Clinical results of endovascular stent graft repair for fifty cases of thoracic aortic aneurysms

Between February 1995 and December 1997, 50 cases (55 lesions) of thoracic aortic aneurysms including 20 cases of aortic dissections were treated with an endovascular technique using the stent grafts. All patients were treated in the operating room under general anesthesia and the stent grafts were implanted through 18 Fr. or 20 Fr. sheathes via femoral arteries under fluoroscopic guidance. The stent graft was composed of several units of self-expanding stainlesssteel Z stents covered with an ultra-thin polyester fabric. Stent graft deployment was technically successful in 53 of 55 lesions (delivery success rate: 96.4%). Exclusion of the aneurysms and entry closing without endoleak were achieved within two weeks after the operation in 43 of 53 lesions (initial success rate: 81.1%). Endoleak was found in 10 lesions (minor endoleak: 8 and major endoleak: 2 lesions). Two patients died in the periopertive period of delivery failures as injury to external iliac artery and damage to the delivery sheath caused by tortuous and narrow access routes. Endovascular stent graft repair of thoracic aortic aneurysms is minimally invasive operation in comparison with conventional surgical graft replacement with extracorporeal circulation. These early results suggest that the stent graft repair is possibly safe and useful treatment for the patients of thoracic aortic aneurysms especially in high risk patients. However, careful long-term follow-up is necessary to prove the value and the effects of this endovascular treatment and improvement of the stent graft system and technical training of endovascular surgery for operators are required to reduce the delivery failure and to determin the stent graft repair is reliable treatment.     

微创腔内隔绝术治疗降主动脉夹层动脉瘤

目的：探讨腔内隔绝术（ＥＶＧＥ）治疗降主动脉夹层动脉瘤（ＤＡＡ）的临床应用价值。方法：２３例ＤｅｂａｋｅｙⅢ型ＤＡＡ患者,经股动脉将直形人造血管－支架复合体（移植物）导入夹层动脉瘤裂口处,支架张开使人造血管固定于裂口附近的动脉壁上,将裂口封闭,消除动脉瘤破裂的危险。结果：３例术中出现内漏的病人,经即时附加导入移植物而将漏门封闭。全部获得成功。结论：ＥＶＧＥ治疗ＤＡＡ,创伤小、并发症少、术后恢复快,有广阔的临床应用前景。     

Treatment of complex intracranial aneurysms with a telescoping stent technique

Background and Object Complex intracranial aneurysms present a treatment challenge for both open and endovascular modalities of treatment. This report seeks to illustrate a series of patients with aneurysms treated with telescoping stents as a method of flow diversion for small and fusiform intracranial aneurysms.Material and Methods A retrospective evaluation of six patients treated with a telescoping stent technique utilizing available stents (at that time before the pipeline era) for complex cerebral aneurysms between January 2009 and January 2010 was performed. Five patients had dissecting aneurysms and one patient had a small superior hypophyseal artery aneurysm. One of the patients was treated in the setting of a Hunt and Hess grade IV subarachnoid hemorrhage. Follow-up cerebral angiography was performed postprocedure at 6 months.Results At a mean follow-up period of 9 months, all the patients experienced complete or near-complete occlusion (>95%). No periprocedural complications were noted in this series. No episodes of hemorrhage or thromboembolic complications occurred.Conclusions Overlapping Neuroform and Enterprise stents may induce complete thrombosis of intracranial aneurysms and facilitate parent artery remodeling. The use of self-expanding stents is still an adequate treatment modality, especially if there is a need for vessel wall stabilization rather than flow diversion. The technique is also a sufficient alternative in small intracranial aneurysms not readily amenable to open surgical treatment or traditional endovascular coil embolization.     

Endovascular management of the juxtarenal aortic aneurysm: can uncovered stents safely cross the renal arteries?

A short or otherwise suboptimal neck precludes the use of endovascular repair in 30% to 50% of patients with abdominal aortic aneurysms. Stent-graft fixation in an unsuitable neck carries the risk of technical failure owing to development of a proximal endoleak or stent-graft migration. Furthermore, in some patients, the neck dilates postoperatively. Endovascular healing with tissue incorporation into the graft material seems in and of itself insufficient to fixate the stent-graft adequately or to prevent neck dilation. Therefore, neck dilation is often associated with detachment of the stent-graft from the aortic wall, which is followed by the development of a proximal endoleak or stent-graft migration. Fixation of stent-grafts can be improved by placing the proximal stent above one or both of the renal artery orifices. Current experimental and clinical data suggest that renal function is not impaired by suprarenal aortic stents during the first year; however, this finding may not apply to all types of stents. Fixation of stent-grafts also may be improved by using stents with barbs that pierce the aortic wall. Additionally, the force that is exerted on the anchoring device may well be reduced by fully stented grafts with an associated increase in column strength. In the future, the risk of neck dilation and stent-graft dislodgement might also be limited by novel techniques such as laparoscopic banding of the neck or endoluminal stapling devices.     

复杂瘤颈的近肾腹主动脉瘤腔内修复中烟囱技术的应用

目的探讨瘤颈解剖复杂的近肾腹主动脉瘤(juxtarenal aortic aneurysms,JAA)腔内修复(endovascular aneurysmrepair,EVAR)中应用烟囱技术的价值。方法 2007年1月～2011年10月,对7例瘤颈复杂的JAA采用EVAR治疗。由于瘤颈解剖结构不适于标准的腔内修复方案,术中自肱动脉穿刺预先于可能被覆膜支架主体覆盖的肾动脉置入导丝,置入修复腹主动脉瘤的覆膜支架主体后造影明确肾动脉覆盖情况,于相应肾动脉置入自膨支架或球囊扩张支架,以延长瘤颈长度使之符合EVAR要求,并有效保护肾动脉(即烟囱技术),然后再完成标准EVAR操作。结果 7例手术全部获成功。7例使用9枚肾动脉支架,其中5枚球扩支架,4枚自膨支架。腔内治疗最后的造影显示:腹主动脉瘤(abdominal aortic aneurysm,AAA)瘤腔隔绝良好,肾动脉血流良好。术中1例近端Ⅰ型内漏,近端增加Cuff后内漏消失;1例造影显示少量的Ⅱ型内漏,无须处理。7例随访1～52个月,平均11.6月:1例术后2个月因心功能衰竭死亡;1例Ⅱ型内漏术后3个月随访内漏消失;肾动脉烟囱支架均保持通畅。结论对于不适宜行开腹手术治疗的瘤颈解剖不佳的JAA,烟囱技术是传统EVAR技术的有效补充,远期效果及肾动脉支架长期通畅性尚需要进一步观察。     

采用胸分支型主动脉支架人工血管对主动脉弓降部夹层行腔内修复治疗

目的探讨采用胸分支型主动脉支架人工血管治疗累及左锁骨下动脉的主动脉弓降部夹层的临床效果。方法自2004年2月至2004年6月,采用血管腔内胸分支型主动脉支架人工血管治疗主动脉弓部夹层14例。14例均为StanforB型主动脉夹层,原发破裂口距左锁骨下动脉开口2～13mm,平均8．7mm。分支型支架由主动脉段支架和分支段支架组成,支架直径较相应支撑部位动脉直径大15％～20％。治疗在血管造影室进行,应用定位导丝、在透视下将分支型主动脉支架人工血管送人并连续释置入主动脉弓和左锁骨下动脉。结果支架释放全部成功。14例患者共放置14只分支型主动脉支架和2只可弯曲型支架人工血管,封闭夹层破裂口,夹层真腔全部恢复正常直径。无远端动脉并发症发生,无死亡病例。全部患者术后恢复正常活动。结论胸分支型主动脉支架人工血管适合于修复破裂口位于左锁骨下动脉开口旁的主动脉弓部夹层。     

Flow changes caused by the sequential placement of stents across the neck of sidewall cerebral aneurysms

OBJECT: The goal of this study was to quantify the reduction in velocity, vorticity, and shear stresses resulting from the sequential placement of stents across the neck of sidewall cerebral aneurysms. METHODS: A digital particle image velocimetry (DPIV) system was used to measure the pulsatile velocity field within a flexible silicone sidewall intracranial aneurysm model and at the aneurysm neck-parent artery interface in this model. The DPIV system is capable of providing an instantaneous, quantitative two-dimensional measurement of the velocity vector field of "blood" flow inside the aneurysm pouch and the parent vessel, and its changes at varying stages of the cardiac cycle. The corresponding vorticity and shear stress fields are then computed from the velocity field data. Three Neuroform stents (Boston Scientific/Target), each with a strut thickness between 60 and 65 microm, were subsequently placed across the neck of the aneurysm model and measurements were obtained after each stent had been placed. The authors measured a consistent decrease in the values of the maximal averaged velocity, vorticity, and shear stress after placing one, two, and three stents. Measurements of the circulation inside the sac demonstrated a systematic reduction in the strength of the vortex due to the stent placement. The decrease in the magnitude of the aforementioned quantities after the first stent was placed was remarkable. Placement of two or three stents led to a less significant reduction than placement of the first stent. CONCLUSIONS: The use of multiple flexible intravascular stents effectively reduces the strength of the vortex forming in an aneurysm sac and results in a decrease in the magnitude of stresses acting on the aneurysm wall.