Stent fracture after transjugular intrahepatic portosystemic shunt placement using the bare metal stent/stent-graft combination technique

BACKGROUND A transjugular intrahepatic portosystemic shunt(TIPS)is widely placed to treat portal hypertension.Because the Viatorr®stent(W.L.Gore and Associates,Flagstaff,AZ,United States)is not available in all hospitals in China,the bare metal stent(BMS)/stent-graft combination technique is still popular for TIPS construction.Stent fracture is a complication after TIPS placement using this technique,with limited available literature focusing on it.AIM To assess the incidence of stent fracture after TIPS placement using the BMS/stent-graft combination technique and to identify the risk factors for stent fracture.We proposed technique modifications to improve the clinical results of TIPS placement with the BMS/stent-graft combination technique.METHODS We retrospectively analyzed the computed tomography(CT)data of all patients with portal hypertension who underwent the TIPS procedure between June 2011 and December 2021 in a single center.Patients implanted with the BMS/stent graft and had follow-up imaging data available were included.We identified patients with stent fracture and analyzed their characteristics.Multivariable logistic regression was applied to identify the potential predictors of stent fracture.RESULTS Of the 68 included patients,stent fracture occurred in seven(10.3%)patients.Based on CT images,the stent fractures were categorized into three types.Our study consisted of four(57.1%)type I fractures,one(14.3%)type II fracture,one(14.3%)type IIIa fracture,and one(14.3%)type IIIb fracture.After adjusting for covariates,multivariable logistic regression revealed that the risk factors for stent fracture were the implantation of a greater number of stents[adjusted odds ratio(aOR)=22.2,95%confidence interval(CI):1.2-415.4,P=0.038]and a larger proximal sagittal stent bending angle(aOR=1.1,95%CI:1.0-1.3,P=0.020).CONCLUSION Stent fracture occurred in approximately 10%of patients with portal hypertension who underwent TIPS with the BMS/stent-graft combination technique.The number of implanted stents and stent bending angle at the inferior vena cava end were predictors of stent fracture,which suggests that the incidence of stent fracture could potentially be reduced by procedural modifications.

Stent-grafts for the treatment of TIPS dysfunction:Fluency stent vs Wallgraft stent

AIM:To evaluate the clinical efficacy of an expanded polytetrafluoro-ethylene-covered Fluency stent compared with that of a polyethylene terephthalate-covered Wallgraft stent for the management of transjugular intrahepatic portosystemic shunt(TIPS)dysfunction.METHODS:A retrospective review of patients who underwent TIPS revision with stent-grafts between May 2007 and June 2011 was conducted.The patients were divided into two groups according to the stentgrafts implanted:the Fluency stent(Bard Incorporated,Karlsruhe,Germany)and the Wallgraft stent(Boston Scientific,Galway,Ireland).The primary patency rates were calculated and compared using the Kaplan-Meier method.RESULTS:A total of 73 patients were evaluated in this study:33 with Fluency stents and 40 with Wallgraft stents.The primary patency rates at 12 and 24 mo were 91% and 85%,respectively,in the Fluency stent group and 78% and 63%,respectively,in the Wallgraft stent group.The primary shunt patency rates after TIPS revision were significantly better with the Fluency stent than with the Wallgraft stent(P = 0.033).CONCLUSION:TIPS revision with the Fluency stent has higher medium-term patency rates than that with the Wallgraft stent.

Experimental and computational studies on the flow fields in aortic aneurysms associated with deployment of AAA stent-grafts

Pulsatile flow fields in rigid abdominal aortic aneurysm （AAA） models were investigated numerically, and the simulation results are found in good agreement with particle image velocimetry （PIV） measurements. There are one or more vortexes in the AAA bulge, and a fairly high wall shear stress exists at the distal end, and thus the AAA is in danger of rupture. Medical treatment consists of inserting a vascular stent-graft in the AAA, which would decrease the blood impact to the inner walls and reduce wall shear stress so that the rupture could be prevented. A new computational model, based on porous medium model, was developed and results are documented. Therapeutic effect of the stent-graft was verified numerically with the new model.

Endovascular stent-grafts for acute and chronic type B aortic dissection: comparison of clinical outcomes

Objective To evaluate the early and mid-term results of endovascular repair for acute and chronic type B aortic dissection, and to compare the clinical outcomes between the 2 groups. Methods From May 2002 to December 2006, 50 patients with type B aortic dissection were treated by endovascular stent-graft. There were 23 patients in the acute aortic dissection (AAD) group and 27 patients in the chronic aortic dissection (CAD) group. All patients were followed up from 1 to 54 months (average, 17±16 months).The immediate and follow-up clinical outcomes were documented and compared between the 2 groups. Results Placement of endovascular stent-grafts across the primary entry tears was technically successful in all 50 patients. Compared to the CAD group, the AAD group had a higher percentage of pleural effusion (17.4% vs. 0%, P=0.04) and visceral /leg ischemia (26.1% vs 3.7%, P=0.04). Procedure related complications, including endoleak and post-implantation syndrome, occurred more frequently in the AAD group than in the CAD group (21.7% vs 3.7% and 30.4% vs 11.1%, respectively; P=0.08 and P=0.04). Kaplan–Meier analysis showed no difference in the survival rate at 4 years between the 2 groups (86.4% vs 92.3%, P=0.42 by log-rank test). However, the event-free survival rate was higher in patients with chronic dissection than in patients with acute aortic dissection(96.2% vs 73.9%; P=0.02 by log-rank test). Conclu- sions Endovascular repair with stent-graft was safe and effective for the treatment of both acute and chronic type B aortic dissection. However, both immediate and long term major complications occurred more frequently in patients with acute dissection than in those with chronic dissection.

Stent-grafts placement for treatment of massive hemorrhage from ruptured hepatic artery after pancreaticoduodenectomy

AIM:To present a series of cases with life-threatening hemorrhage from ruptured hepatic artery pseudoaneurysm after pancreaticoduodenectomy(PD) treated with placement of stent-grafts.METHODS:Massive hemorrhage from ruptured hepatic artery pseudoaneurysm after PD in 9 patients(6 men,3 women) at the age of 23-75 years(mean 48 years),were treated with placement of percutaneous endovascular balloon-expandable coronary stent-grafts.All patients were not suitable for embolization because of a non-patent portal vein.One or more stent-grafts,ranging 3-6 mm in diameter and 16-55 mm in length,were placed to exclude ruptured pseudoaneurysm.Followup data,including clinical condition,liver function tests,and Doppler ultrasound examination,were recorded at the outpatient clinic.RESULTS:Immediate technical success was achieved in all the 9 patients.All stent-grafts were deployed in the intended position for immediate cessation of bleeding and preservation of satisfactory hepatic arterial blood flow.No significant procedure-related complications occurred.Recurrent bleeding occurred in 2 patients at 16 and 24 h,respectively,after placement of stent-grafts and treated with surgical revision.One patient died of sepsis 12 d after the interventional procedure.The remaining 6 patients were survived when they were discharged.The mean follow-up time was 10.5 mo(range 4-16 mo).No patient had recurrent bleeding after discharge.Doppler ultrasound examination verified the patency of hepatic artery and stent-grafts during the follow-up.CONCLUSION:Placement of stent-grafts is an effective and safe procedure for acute life-threatening hemorrhage from ruptured hepatic artery pseudoaneurysm.

Short-term results in canines of novel stent-graft design for chimney technique in TEVAR

Introduction:Parallel stent-stent grafting is a major endovascular technique used to preserve the supra-aortic branches during thoracic endovascular aortic repair(TEVAR)of aortic pathologies involving the aortic arch.The short-and mid-term results of this technique are satisfactory;however,endoleak remains a major concern.Thus,here we designed a new chimney stent-graft to decrease the endoleak rate.Aim:To testify the feasibility and safety of the new chimney stent-graft system in a canine model.Material and methods:Six Labrador retrievers were used.Pre-operative data were collected and all operations were performed under general anesthesia.The main and chimney stent-grafts were implanted through the abdominal aorta and left subclavian artery approaches,respectively.Completion digital subtraction angiography(DSA)was performed to confirm the immediate outcomes.All dogs were fed separately for 6 months and sacrificed after aortic angiography.The thoracic aorta and the main and chimney stent-grafts were harvested for histopathologic examination.Results:No complications were found in follow-up DSA.All branch arteries were patent.In?ammatory responses were observed around the stent-grafts in 3 experimental animals,and slight hyperplasia was observed in the surrounding tissues compared with the normal vessels.There was no mural thrombus in the stent,endothelial cells were noted on the inner surface of the stent,and thrombus was formed in the outer skirt and gutter area.The histopathologic examinations revealed similar results to those of gross necropsy observations.Conclusions:This study demonstrated the feasibility and safety of the Longuette stent-graft and the first to report a revised stent-graft specific for chimney technique.

Fatigue Performance of Fabrics of Stent-Grafts Supported with Z-Stents vs. Ringed Stents

Stent-grafts were commercialized rapidly and gained a broad clinical acceptance over the past two decades. However,relatively more recent recognition of particular stent-graft design shortcomings have been identified which need to be addressed. It appears that various stent-graft designs may be more or less resistant to metal fatigue and /or fabric abrasions which can lead to type III and type IV endoleaks over the long term. Therefore,it is necessary to investigate the fatigue performance of the most common stentgraft designs: Z-stents and ringed stents,in a long-term in vitro fatigue simulation environment. This paper aimed to analyze nondestructively( gross observations) and destructively( fabric characteristics,mechanical and chemical properties) in order to put forward suggestions to improve the fabric and stent characteristics that may prevent type III and IV endoleaks. The fabric supported with ringed stent-grafts remained nearly completely intact after 168h. However, the fabric supported with Z-stents demonstrated significant damage. Fabric characteristics and tensile strength of the fibers did not present a significant difference between the control and fatigue simulated specimens. The crystallinity declined for both specimens. The fatigue performance of fabrics supported with ringed stents appears to be superior to that supported with Z-stents. The potential for a dynamic and destructive interaction between the apices of Z-stents which can lead to fraying and /or tearing of the graft fabric must be addressed in future designs.

Total endovascular repair of aberrant right subclavian artery using caster branched stent-graft

A 57-year-old man has 20-year history of hypertension presented with intermittent chronic pain in the chest area and shoulder blades over the last three months.Computed tomographic angiography(CTA)on admission revealed a chronic type B aortic dissection(TBAD)with an aberrant right subclavian artery(ARSA)crossed behind the trachea and bovine aortic arch(Figure IB).

Endovascular stent-grafts for acute and chronic type B aortic dissection: comparison of clinical outcomes

Within the recent months, endovascular repair of aortic aneurysms has become a rather interesting alternative to patients considering open surgery. In the past, the procedure was typically and more solely reserved to a selected group of elderly patients with several co-morbidities.……

Mid-term outcomes of left subclavian artery revascularization with Castor stent graft in treatment of type B aortic dissection in left subclavian artery

Background:Here we analyzed mid-term data of thoracic endovascular aneurysm repair(TEVAR)surgery with Castor single-branched stent graft placement for the management of Stanford type B aortic dissection(STBAD)involving the left subclavian artery(LSA).Methods:Between April 2014 and February 2019,32 patients with STBAD involving a Castor single-branched stent graft were included.We analyzed their outcomes,including technical success rate(TSR),surgical duration(SD),presence of ischemia,perioperative complications,LSA patency,and survival rate(SR),using computed tomography angiography and clinical evaluation during mid-term follow-up.Results:The mean patient age was 54.63±12.37 years(range,36–83 years).The TSR was 96.88%(n=31/32).The mean SD was 87.44±10.89 with a mean contrast volume of 125.31±19.30 mL.No neurological complications or deaths occurred during the study period.The patients had a mean hospital stay of 7.84±3.20 days.At a mean follow-up of 68.78±11.26 months,four non-aortic deaths(12.5%)were observed.The LSA patency rate was 100%(n=28/28).There was only one case of type I endoleak immediately after surgery(3.12%)(type I from LSA).However,none of the patients experienced type II endoleaks,and there were no cases of retrograde type A aortic dissection or stent graft-driven new distal entry.Finally,all patients exhibited good LSA patency.Conclusion:TEVAR using a Castor single-branched stent graft may be a highly feasible and efficient procedure for the management of STBAD involving the LSA.

Case Report of a Pseudoaneurysm of Ascending Aorta Treated by Stent

Pseudoaneurysms of the ascending aorta are a rare complication of aortic and cardiac surgery. In this article, we present a clinical case of a 56-year-old patient with a fortuitous diagnosis of a pseudoaneurysm of ascending aorta that was treated by an endovascular stent-graft. We discuss in this article the diagnostic and therapeutic aspect of the case and the place of endovascular treatment for the ascending aorta.

腔内隔绝治疗77例Stanford B型夹层动脉瘤的报告

目的覆膜支架已日益广泛用于治疗Stanford B型夹层动脉瘤。文中观察研究覆膜支架介入治疗Stanford B型夹层动脉瘤的疗效。方法对77例Stanford B型夹层动脉瘤行覆膜支架介入治疗,观察疗效与长期预后。结果 77例均成功封堵主动脉破口,近期死亡2例,存活患者5年生存率为73.3%,生活质量基本不受影响。结论覆膜支架介入治疗Stanford B型夹层动脉瘤是安全有效的方法,远期疗效满意。

“烟囱”技术在主动脉弓病变腔内修复术中的应用

目的:探讨'烟囱'技术在主动脉弓病变腔内修复术中应用的方法及疗效。方法:回顾性统计2010年8月至2014年8月应用'烟囱'技术处理主动脉弓病变的25例患者的方法、结果和术后并发症等。结果:本组25例主动脉弓病变腔内修复技术中应用了'烟囱'技术,男性18例,女性7例,年龄38~78(65±5.8)岁。针对左颈总动脉的'烟囱'技术5例,针对左锁骨下动脉的'烟囱'技术20例。25例患者均获得技术成功。3例术后即刻造影提示少量I型内漏,未处理,术后1个月复查内漏消失;2例患者出现左上肢乏力,其中1例伴头晕,随访过程中逐渐恢复,无肢体缺血坏死。所有'烟囱'支架均通畅,无主动脉覆膜支架移位、内漏等并发症。结论:'烟囱'技术为近端锚定区不足的主动脉弓部病变提供了完全腔内微创治疗的方法,短期随访结果满意。

胸、腹主动脉病变的血管内治疗

目的探讨胸、腹主动脉病变不同血管内治疗方法的临床疗效。方法7例患者,其中DebakeyⅢ型主动脉夹层5例(4例行一体式支架腔内隔绝术,1例行内膜瓣开窗术);DebakeyⅢ型主动脉夹层外院外科人造血管置换术后降主动脉假性动脉瘤形成1例(行一体式支架腔内隔绝术);肾动脉开口以下腹主动脉瘤1例(行分体式支架腔内隔绝术)。结果5例一体式支架腔内隔绝术均获成功,2例出现Ⅰ型内漏,1例经球囊扩张后内漏消失,1例30 min后内漏减少,未处理;1例内膜瓣开窗术后患者双下肢缺血症状消失;1例分体式支架腔内隔绝术后造影提示动脉瘤消失,无内漏发生。结论应用血管内支架移植物或内膜瓣开窗术治疗胸、腹主动脉病变安全有效,其中分体式支架的临床应用具有更好的前景。

主动脉夹层腔内隔绝术围手术期的护理

目的探讨主动脉夹层腔内隔绝术患者的围手术期护理措施。方法对52例主动脉夹层行腔内隔绝术患者的护理情况进行回顾性分析和总结。结果48例患者治愈出院,4例患者术后出现急性肾功能衰竭,转院治疗。结论精心有效的围手术期护理可减少并发症发生,提高患者生存率和改善预后,进而提高其生活质量。

颅内支架重叠技术治疗未破裂椎-基底动脉夹层动脉瘤

目的探讨颅内支架重叠技术在未破裂椎-基底动脉夹层动脉瘤(VBDAs)治疗中的临床效果。方法回顾性分析10例VBDAs患者,共12个未破裂VBDAs。运用颅内支架重叠技术,采用LEO支架进行治疗(对9例患者采用2枚支架,1例采用3枚支架),通过改变动脉瘤腔的血流动力学栓塞动脉瘤,并保留载瘤动脉。所有患者均完成临床和影像学随访。结果①影像学检查表现分别为近端狭窄、串珠样变、波纹状、双腔征、壁间血肿。②术后即刻造影均显示,动脉瘤腔内对比剂滞留。1例患者术中支架移位,但未导致神经功能障碍。2例患者术后出现短暂性脑缺血发作,对症治疗后缓解。其余患者未出现神经系统并发症。出院前头部CT检查均未见新发脑梗死。③术后6个月造影结果显示,6个夹层动脉瘤完全闭塞,6个夹层动脉瘤部分闭塞。临床随访8～27个月,10例患者的最终改良Rankin评分均为0分,随访中患者均未出现该技术相关的并发症。结论颅内支架重叠技术治疗未破裂VBDAS是安全和有效的。

483例脑动静脉畸形患者不同治疗方法的治疗结果分析

目的:对脑动静脉畸形各种治疗方法的优缺点进行分析探讨。方法:483例脑动静脉畸形患者分为显微手术治疗组、伽玛刀治疗组、血管内治疗组、保守治疗组,通过随访(平均随访时间2.5年),分析各治疗方法的疗效、风险及预后。结果:显微手术治疗组的全切除率为93.5%,近期并发症发生率为29.4%,远期永久性并发症的发生率为6.75%,再出血率为1.84%,总病死率为1.23%。伽玛刀治疗组无近期并发症,远期并发症率为3.6%,再出血率为12.5%,无死亡。血管内治疗组近期并发症发生率为19.9%,远期永久性并发症发生率为6.0%,再出血率为21%,总病死率为7.0%。保守治疗组再出血率为3.33%,无死亡。结论:显微手术治疗仍是治疗动静脉畸形最可靠的方法,伽玛刀和血管内治疗是多手段联合治疗中的重要组成部分。

药物洗脱支架在后循环动脉狭窄治疗中的应用

目的研究在后循环动脉狭窄治疗中应用药物洗脱支架的安全性和疗效性。方法经常规造影证实椎动脉狭窄者30例,接受支架置入治疗者19例。局麻或全麻下经右股动脉以Seldinger技术置入6F导管鞘,在相应导丝辅助下使导引导管进入锁骨下动脉或椎动脉,血管造影后沿导引导管插入0.014英寸、300cm或205cm导丝至狭窄远端,经此微导丝交换置入相应规格球囊扩张式CypherTM支架(10例)或TAXUSTM支架(9例)。结果19例患者手术均成功,无死亡和并发症,置入支架贴壁良好,血流明显改善,狭窄远端分支血管(小脑后下动脉等)充盈明显改善,狭窄率由原来的平均87.5%降至平均5.2%。15例表现为眩晕症状的患者术后症状消失12例(80%),改善3例。表现为共济失调的6例患者术后共济运动基本正常4例,明显改善2例,表现为小脑性语言障碍的1例患者术后明显改善。完成至少1次造影随访的患者15例,经DSA证实无再狭窄发生。所有患者门诊随访,最长18个月。结论药物洗脱支架在后循环动脉狭窄的治疗中安全、有效,在短期内能防止术后再狭窄,长期疗效需进一步观察,需要大样本的随机对照研究进一步证实。

大脑中动脉远端动脉瘤血管内治疗的单中心经验

目的探讨应用血管内治疗技术治疗大脑中动脉远端动脉瘤的安全性和有效性。方法连续纳入2009年1月至2016年12月于第二军医大学附属长海医院神经外科行血管内治疗的大脑中动脉远端动脉瘤13例患者(共14个动脉瘤)的病历资料进行回顾分析,血管内治疗包括弹簧圈、弹簧圈结合液体栓塞材料或单纯应用液体栓塞材料进行动脉瘤瘤内栓塞或闭塞载瘤动脉。以Raymond分级判定动脉瘤即刻治疗结果,以改良Rankin量表(mRS)评价患者临床预后。采用DSA行影像学随访,并与即刻治疗结果进行比较以判断动脉瘤是否复发。结果 13例患者中,男8例,平均年龄(40±14)岁。动脉瘤最大径为1.0~12.0 mm,中位数为大小4.5 mm。对14个动脉瘤均成功行血管内治疗,其中4个行瘤内栓塞,保留载瘤动脉;10个行动脉瘤及载瘤动脉闭塞。12个动脉瘤术后即刻造影不显影,2个瘤体残留。血管内治疗术后未见新发神经功能障碍及相关并发症。临床随访期限为9~96个月,中位数时间30.9个月,除2例患者血肿清除术后残余神经功能障碍外,其余患者临床预后良好。12个动脉瘤接受影像学随访,随访期限6~24个月,中位数时间15.2个月,均未出现动脉瘤复发。结论应用血管内治疗技术治疗大脑中动脉远端动脉瘤安全、有效,在制定治疗方案时可以选择性采用血管内介入技术。

电解可脱性弹簧圈血管内栓塞颅内动脉瘤的技术及并发症防治

目的 总结以电解可脱性弹簧圈（GDC）血管内栓塞治疗颅内动脉瘤的技术要点、并发症及其防治经验。方法 采用GDC对168例颅内动脉瘤患者进行动脉瘤囊内栓塞。结果成功栓塞168个动脉瘤，其中l00％闭塞的144个，95％闭塞的14个，90％闭塞的10个，全组6例死亡，死亡率3．6％。术中并发动脉瘤破裂3例，脑血管痉挛9例，脑梗死2例，术后弹簧圈末端逸出2例，3例复发者经二次补充GDC栓塞而治愈。随访5～54个月，全组术后均无再出血。结论 动脉瘤的血管内治疗应根据病情进行个体化设计，并采用与之相应的栓塞技术才能最大限度的提高动脉瘤栓塞的治愈率、降低并发症。