Device migration after endovascular abdominal aortic aneurysm repair: experience with a talent stent-graft

PURPOSE: Device migration (DM) may cause late failure after endovascular aortic aneurysm repair (EVAR). Computed tomography (CT) scans following EVAR were reviewed to establish the frequency of DM and whether it can be predicted. MATERIALS AND METHODS: Fifty-five patients underwent EVAR with a Talent stent-graft with suprarenal fixation. CT with a fixed protocol was performed at regular intervals. Patient demographics, risk factors, procedure details, and follow-up events were reviewed. Two observers, blinded to each other, reviewed axial images and mutliplanar reformats of the CT scans. DM was defined as a change of > or = 10 mm in the distance between a reference vessel (celiac axis/superior mesenteric artery) and the proximal device. Follow-up was performed for a minimum of 2 years (mean, 3 years; range, 2-5 years). RESULTS: DM was detected in six of 38 patients (15.8%) by 2 years. There were no new cases of migration in the 19 patients at 3 years but one new case in the six patients at 4 years (16.6%). Mean migration over 2 years was 4.8 mm +/- 4.2 mm. One patient with DM developed a type I endoleak that required reintervention. This patient developed a further endoleak and died following surgery for rupture. Top neck enlargement was the only predictive factor identified, present in 71% of patients with DM (P = .056). CONCLUSION: DM occurred in a small proportion of patients; closer follow-up intervals may be necessary in patients with short/enlarging proximal necks.     

Embolotherapy of persistent endoleaks after endovascular repair of abdominal aortic aneurysm with the ancure-endovascular technologies endograft system.

PURPOSE: Endoleak is a potential complication after endovascular repair of abdominal aortic aneurysm (AAA). It may result in continued growth of the aneurysm and potentially result in aneurysm rupture. The authors present their experience with embolotherapy in patients with persistent perigraft flow treated with the Ancure-Endovascular Technologies endograft system. MATERIALS AND METHODS: Between February 1996 and August 1998, 54 patients underwent successful repair of AAA with use of the Ancure system. All underwent operative angiography and discharge computed tomography (CT). Follow-up included CT at 6, 12, and 24 months, and CT was also performed at 3 months if an endoleak was present on the discharge CT. Persistent endoleak was defined as perigraft flow still present on the 6-month CT. Seven of 21 initial endoleaks persisted at 6 months. Six patients returned for embolization of the perigraft space and outflow vessels including lumbar arteries and the inferior mesenteric artery (IMA). RESULTS: Five of the six patients had leaks from the proximal (n = 1) or distal attachment sites (n = 4) of the Ancure system with outflow into lumbar arteries and/or the IMA; one leak was caused by retrograde IMA flow. The six patients underwent nine embolization procedures with only one minor complication. Follow-up CT showed complete resolution of endoleak and decrease in size of the aneurysm sac in all patients. CONCLUSIONS: Although endoleak is commonly seen initially with the Ancure system, persistent leak occurred in 13% of the patients in the study. Persistent flow in most patients arises from a graft attachment site combined with patent outflow vessels such as the IMA or lumbar arteries. Persistent endoleaks can be effectively and safely embolized with use of a combination of coil embolization of the perigraft space and embolization of outflow vessels. Such intervention resulted in a decrease in size of the aneurysm sac.     

Troubleshooting techniques for abdominal aortic aneurysm endograft placement: when things go wrong

Since the Food and Drug Administration approved the Ancure (Guidant Corp, Menlo Park, CA) and AneuRx (Medtronic Corp, Minneapolis, MN) abdominal aortic aneurysm stent-grafts, there has been a tremendous increase in the number of stent-graft implantations, both in the United States and worldwide. Successful stent-graft deployment requires complex interventional skills and accurate preprocedure planning. Even the most skilled operator may experience intraoperative difficulties during graft deployment. There are intraprocedural complications that are common to all stent-grafts, as well as specific complications that are unique to the particular stent-graft being implanted. The first step to managing an intraprocedural complication is to be able to quickly recognize that a deployment difficulty has occurred. The interventionalist must then be ready to use common troubleshooting techniques to rectify or avoid complications of stent-graft delivery.     

Endovascular repair of the abdominal aortic aneurysm with the ancure endograft: CT follow-up of perigraft flow and aneurysm size at 6 months

PURPOSE: Perigraft flow--flow outside the graft lumen but contained within the abdominal aortic aneurysm (AAA)--is a potential complication after endovascular repair of AAA. Such flow may permit AAA growth and rupture. The purpose of this study is to evaluate with computed tomography (CT) the rate of spontaneous closure of perigraft flow and the effect of persistent flow on AAA diameter. MATERIALS AND METHODS: During a 30-month period, the authors evaluated all CT scans in 50 patients who underwent AAA repair using the Ancure endograft system. CT was performed at discharge, 6, 12, and 24 months, and at 3 months if there was perigraft flow at discharge. Scans were reviewed for the presence, size, and location of perigraft flow, and measurement of AAA diameter. Transcatheter embolization was performed on those patients with persistent leak at 6 months. RESULTS: Sixteen (32%) of 50 patients demonstrated perigraft flow on CT performed within 72 hours of placement. Resolution of perigraft flow by 6 months was found in nine (56%) of the 16 patients, in whom AAA size had decreased in five, had increased in none, and was unchanged in four. Seven patients had persistent leaks at 6-month CT; AAA size had decreased in one, had increased in one, and was unchanged in five. In 34 patients without leaks, AAA size had decreased in nine, had increased in one, and was unchanged on 24. There was no statistically significant difference for the relationship between resolution or persistence of perigraft flow and subsequent course of AAA diameter (P = .16). CONCLUSIONS: Although perigraft flow is frequently seen (32%) early after repair of AAA with the Ancure system, spontaneous resolution by 6 months occurs in 56% of cases. AAA size decreased in a larger percentage of patients in whom perigraft leak was absent or resolved by 6 months compared with those in whom perigraft leak persisted at 6 months.     

Complications following endovascular abdominal aortic aneurysm repair

There is a growing population of patients who have undergone endovascular abdominal aortic aneurysm repair (EVAR) and thus there is an increasing likelihood that radiologists who are unfamiliar with this technique and its complications will have to report radiological investigations on one of these patients. The purpose of this review is to describe and illustrate the normal and abnormal radiological appearances after EVAR on plain radiography, ultrasound and CT.     

Renewed endovascular repair for recurrent acute abdominal aortic aneurysm

The aim of the study was to describe the successful endovascular management of a patient who was admitted urgently with a second episode of acute abdominal aortic aneurysm (AAA) 30 months after emergency endovascular abdominal aortic aneurysm repair (eEVAR) for a ruptured AAA. The patient, an 84 year-old male physician, presented with severe acute abdominal and back pain. Contrast-enhanced computer tomography scanning showed type III endoleak owing to complete disconnection of both graft limbs and the prosthetic main body. Treatment consisted of acute stent-grafting with two bridging stent-grafts to seal the endoleak and reline the graft. The patient is alive and well 6 months postoperatively. This case indicates the need for follow-up after eEVAR, but also that complications can be managed endovascularly.     

Endovascular treatment of endoleaks after endovascular abdominal aortic aneurysm repair: personal experience

PURPOSE: This paper describes the different endovascular treatments (cuffs, endografts and embolisation) available for types I, II and III endoleaks occurring after endovascular abdominal aortic aneurysm repair (EVAR). MATERIALS AND METHODS: From January 2000 to June 2006, 134 patients (118 men, 16 women; mean age 75.1 years) underwent EVAR. Ten patients (7%) developed significant endoleaks requiring endovascular treatment. RESULTS: Five endoleaks were type I, two were type II and three were type III. Of the five type I endoleaks, four were proximal and one was distal. The proximal endoleaks were treated by cuff deployment, whereas the distal endoleak was treated with a bifurcated graft. Of the two patients with type II endoleak, one was treated by translumbar puncture and coil embolisation, and the other was treated by superselective embolisation of the lumbar feeding vessel with nonresorbable particles. Of the three patients with type III endoleak, two were treated by deploying an aortouniiliac endograft inside the bifurcated graft and the other by implanting a cuff to restore continuity between the graft body and the contralateral limb. Endovascular treatment was successful in 6/10 cases, whereas three cases required surgical conversion. One patient did not undergo surgery owing to poor general condition. CONCLUSIONS: The reported incidence of endoleaks after EVAR is 10%-20%. Significant endoleaks should be treated promptly. Endovascular treatment can be done with different techniques, but success in not constant due to adverse anatomical conditions and technical difficulties.     

Duodenal obstruction after repair of abdominal aortic aneurysm

Two cases are reported of obstruction of the transverse duodenum within the first 2 weeks after repair of an abdominal aortic aneurysm. Abdominal radiography, upper gastrointestinal examination, and computed tomography all aid in the diagnosis.     

腹主动脉瘤腔内修复术22例围手术期处理回顾性总结

目的 总结腹主动脉瘤腔内修复术(EVAR)围手术期处理的临床经验.方法 回顾分析22例腹主动脉瘤患者EVAR临床经过,通过术前对主要脏器功能进行评估和保护,CTA测量近远侧瘤颈长度、直径、角度和构型,瘤体与分支动脉的关系,最低肾动脉开口至腹主动脉分叉的距离,导入途径的直径、扭曲和钙化程度.根据CTA测量结果,选择覆膜支架和手术方式.术时采用局麻20例,中转全麻l例,1例通过髂总动脉重建导人途径采用硬膜外麻醉,1例合并Stanf.0rd A型主动脉夹层,术时采用全麻.在支架释放前准确定位最低肾动脉位置,至少保留一侧通畅的髂内动脉,若双侧需要覆盖,分期覆盖或髂内动脉重建.支架植入后复查造影,有无内漏.正确判断内漏类型并进行相应处理.支架近端Ⅰ内漏2例,球囊扩张1例,植入Cuff 1例;支架远端Ⅰ内漏1例,球囊扩张时,动脉破裂,行人工血管补片修补术;Ⅲ型内漏3例,球囊扩张后支架植入1例.1例合并Starford A型主动脉夹层先行胸主动脉腔内修复术,后行EVAR.术后7一10 d复查CTA,以后每年复查1次.结果 EVAR手术全获成功.主要并发症为单侧髂肢扭结继发血栓形成,Fogarty导管取栓并支架植人1例;腹壁切口裂开1例,清创缝合;无手术死亡,随访6个月～5年,患者均存活.结论 CTA图像质量高、测量准确,是EVAR术前评估和术后随访的金标准.EVAR是高危、高龄腹主动脉瘤患者有效的治疗方法.     

Bifurcated drum occluder endograft for treatment of abdominal aortic aneurysm: an experimental study in dogs

PURPOSE: To evaluate a new, low profile, home-made, bifurcated drum occluder endograft (BDOEG), designed for percutaneous, transcatheter treatment of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: AAA was created in 10 dogs with over-dilated Palmaz stents. To prevent back filling, the lumbar arteries, inferior mesenteric artery, and common internal iliac arteries were embolized. The BDOEG was constructed of a drum occluder device and two PTFE endografts. The drum device consisted of a modified Z stent with Dacron stretched across and held within the ends of the stent, each with two 8 x 6-mm slits through which PTFE endografts were delivered. The PTFE endografts were 8 mm in diameter and 9.5 cm in length. Preloaded, the BDOEG was delivered through a 10-F sheath from both femoral arteries in a three-step procedure. All 10 animals were treated with BDOEG. Aortography was performed immediately, 6 weeks, and 12 weeks after stent-graft placement. Five animals were killed at 6 weeks and five were killed at 3 months. Gross and histologic evaluation was performed. RESULTS: The infrarenal aortic diameters and both external iliac arteries ranged from 8.0 mm to 10.3 mm (mean, 9.4 mm +/- 0.6) and from 5.2 mm to 6.8 mm (mean, 5.8 mm +/- 0.5), respectively. Creation of the AAA was successful in all 10 dogs. AAA diameters ranged from 13.7 mm to 15.9 mm (mean, 14.9 mm +/- 0.7). Complete exclusion of the AAA was achieved immediately after BDOEG placement and aneurysms remained excluded without perigraft leak to the time of killing in all 10 animals. There was a high incidence of aortoiliac limb occlusion. Occlusion of 12 aortoiliac limbs (60%) caused by intimal hyperplasia at the distal end of the endografts in iliac arteries developed in nine animals (90%). In six animals (60%), one limb occluded and, in three animals (30%), there was occlusion of both limbs. CONCLUSION: This study suggests a new approach for treatment of AAA. BDOEG use reduces sheath size for endograft delivery and may eliminate the need for a surgical cut down on femoral arteries. Tapering of the iliac ends of endografts to the size of the artery will be needed to prevent distal intimal hyperplasia.     

Evaluation of the proximal aortic neck enlargement following endovascular repair of abdominal aortic aneurysm: 3-years experience

The aim of this study was to evaluate incidence, potential risk factors and effects on stent-graft migration of proximal neck dilatation after endoluminal repair of abdominal aortic aneurysm (EVAR), and the role of ultrasound (US) in detecting neck enlargement. From November 1998 to October 2001, 90 patients underwent EVAR. On follow-up, US and CT angiography (CTA) were performed, and diameters of the suprarenal and infrarenal aortic necks were monitored. Incidence of significant neck enlargement (≥2.5 mm) and distal stent-graft migration (>10 mm) was calculated. Several factors were evaluated as predictive of neck enlargement. Ultrasound and CTA measurements were compared. The US and CTA examinations were available in 68, 39, and 11 patients at 1, 2, and 3 years follow-up (mean follow-up 15 months). Incidence of significant neck dilatation was 21.8% at the infrarenal level (13, 33, and 36% at 1, 2, and 3 years follow-up) and 13.8% at the suprarenal level (9, 18, and 27% at 1, 2, and 3 years follow-up). Significant stent-graft migration occurred in 14 of 87 patients (16%) and was associated with neck dilatation in 8 (2 suprarenal and 6 infrarenal). No risk factors were identified. Ultrasound was less accurate than CT in measuring neck diameter, in particular at the suprarenal level. Proximal aortic neck enlargement occurs in up to 30% of patients after EVAR and represents the main risk factor for stent-graft migration. The risk of infrarenal neck dilatation is higher at 2 years follow-up, whereas the suprarenal neck enlarges later. Ultrasound is not useful in monitoring neck diameter.     

主动脉瘤腔内修复术一期治愈Stanford A型主动脉夹层并腹主动脉瘤一例

Stanford A型主动脉夹层是一种灾难性疾病,病死率极高[1]。治疗主要以手术为主,即升主动脉或主动脉弓置换术,但手术创伤大,手术病死率达14%～21.6%[2]。自1991年     

Abdominal aortic aneurysm calcification and thrombus volume are not associated with outcome following endovascular abdominal aortic aneurysm repair

Objectives

Aortic calcification and thrombus have been postulated to worsen outcome following endovascular abdominal aortic aneurysm repair (EVAR). The purpose of this study was to assess the association of abdominal aortic aneurysm (AAA) calcification and thrombus volume with outcome following EVAR using a reproducible, quantifiable computed tomography (CT) assessment protocol.

Methods

Patients with elective EVAR performed between January 2002 and 2012 at the Townsville Hospital, Mater Private Hospital (Townsville) and Royal Brisbane and Women’s Hospital (RBWH) were included if preoperative CTAs were available for analysis. AAA calcification and thrombus volume were measured using a semiautomated workstation protocol. Outcomes were assessed in terms of clinical failure, endoleak (type I, type II) and reintervention. Univariate and multivariate analyses were performed. Median follow-up was 1.7 years and the interquartile range 1.0–3.8 years.

Results

One hundred thirty-four patients undergoing elective EVAR were included in the study. Rates of primary clinical success and freedom from reintervention were 82.8 % and 88.9 % at the 24-month follow-up. AAA calcification and thrombus volume were not associated with clinical failure, type I endoleak, type II endoleak or reintervention.

Conclusions

AAA calcification and thrombus volume were not associated with poorer outcome after EVAR in this study.

Key Points

? The association of calcification and thrombus volumes with EVAR outcome is unclear ? Quantifiable methods for assessing calcification and thrombus were not used previously ? This study used reproducible methods for assessing AAA calcification and thrombus volumes     

Low-dose multidetector-row CT-angiography of abdominal aortic aneurysm after endovascular repair

Purpose

To investigate the possibility of reducing radiation dose exposure while maintaining image quality using multidetector computed tomography angiography (MDCTA) with high-concentration contrast media in patients undergoing follow-up after endovascular aortic repair (EVAR) to treat abdominal aortic aneurysm.

Materials and methods

In this prospective, single center, intra-individual study, patients underwent two consecutive MDCTA scans 6 months apart, one with a standard acquisition protocol (130 mAs/120 kV) and 120 mL of iomeprol 300, and one using a low dose protocol (100 mAs/80 kV) and 90 mL of iomeprol 400. Images acquired during the arterial phase of contrast enhancement were evaluated both qualitatively and quantitatively for image noise and intraluminal contrast enhancement.

Results

Thirty adult patients were prospectively enrolled. Statistically significantly higher attenuation values were measured in the low-dose acquisition protocol compared to the standard protocol, from the suprarenal abdominal aorta to the common femoral artery (p < 0.0001; all vascular segments). Qualitatively, image quality was judged significantly (p = 0.0002) better with the standard protocol than with the low-dose protocol. However, no significant differences were found between the two protocols in terms of contrast-to-noise ratio (CNR) (13.63 ± 6.97 vs. 11.48 ± 8.13; p = 0.1058). An overall dose reduction of up to 74% was observed for the low-dose protocol compared with the standard protocol.

Conclusion

In repeat follow-up examinations of patients undergoing EVAR for abdominal aortic aneurysm, a low-dose radiation exposure acquisition protocol provides substantially reduced radiation exposure while maintaining a constant CNR and good image quality.     

Pasturella multicoda infection of an abdominal aortic endograft

Both surgical and endovascular grafts have the rare risk of late secondary infection. Treatment varies based on the clinical setting, but in general the recommendations are that infected endografts be removed and reconstruction performed. In the abdominal aorta this may vary from homograft or other impregnated grafts to excision and extra-anatomic bypass. We discuss an unusual case which we believe serves as a useful review of this still debated area. A 58-year-old male presented with abdominal and back pain. Prior history was notable for human immunodeficiency virus positive status, pulmonary embolism (currently on Coumadin) and two years previously repair of a saccular infra-renal aneurysm with tube graft. The week prior to the onset of symptoms he suffered a noticeable scratch from his cat. Blood cultures were positive for pasturella multicoda. He was transferred to our institution and underwent resection and explantation, with homograft reconstruction. At one year he is alive and well.     

Descending thoracic aneurysm rupture with a known abdominal aortic aneurysm.

The association of abdominal aortic aneurysms with aneurysmal disease of the thoracic aorta is well established. However, rupture of a descending atherosclerotic thoracic aortic aneurysm in association with an infrarenal abdominal aortic aneurysm can present a difficult diagnostic and therapeutic problem to the treating physician. This article presents a case of rupture of an atherosclerotic descending thoracic aortic aneurysm in the face of what clinically appeared to be a leaking or ruptured abdominal aortic aneurysm.