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.     

Follow-up of abdominal aortic aneurysm after endovascular aortic repair: comparison of volumetric and diametric measurement

Purpose

To determine the correlation of maximal diameter measurements with volumetric evaluation of size after endovascular aortic repair (EVAR) of abdominal aortic aneurysms (AAA) using computed tomography angiography (CTA) and to survey its applicability for clinical follow-up.

Materials and methods

73 consecutive patients (2 females, 71 males; age 38–84 years; mean age, 69.1 ± 8 years) with AAA were treated with percutaneous EVAR in a single institution. For follow-up, CTA was performed periodically after EVAR. Images were evaluated for maximal diameter in consensus by two experienced radiologists. Using OsirixTM, volumetric measurements were done by one radiologist, including the entire infrarenal abdominal aorta.

Results

In 73 patients 220 CTA examinations were performed after EVAR with a mean follow-up of 17.3 months (range, 1.8–42.7 months). The mean postinterventional volume of aneurysm was 165.63 ml ± 93.29 ml (range, 47.94–565.67 ml). The mean maximal postinterventional diameter was 5.91 ± 1.52 cm (range, 3.72–13.82 cm). At large over the entire observation period a slight, non-significant decrease of 1.6% (2.58 ml ± 69.05 ml, range 82.82–201.92 ml) in volumes and a 9.3% (mean 0.55 cm ± 1.22 cm, range 2.85–1.93 cm) in diameters were observed. For all examinations a high correlation of volume and diameter was calculated (r = 0.813–0.905; α < 0.01).

Conclusion

For follow-up of abdominal EVAR using CTA there is a high correlation between volumetric and diametric measurements of aneurysm. Based on a daily clinical routine setting, measurements of maximal diameters in cross sectional imaging of AAA after EVAR seems to be sufficient to exclude post interventional enlargement.     

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.     

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.     

采用血管缝合器治疗复杂型腹主动脉瘤腔内隔绝术一例

腹主动脉瘤腔内修复术(TEVAR)常规采用双侧股动脉切开途径置入.我们采用血管缝合器顺利完成1例复杂型TEVAR,现报道如下.患者男,56岁.既往有10年高血压、糖尿病及糖尿病肾病史,行口服药物治疗.3年前发现腹部搏动性包块,CT确诊断为肾下型腹主动脉瘤,当时测得瘤体最大径约35 mm.     

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.     

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.     

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     

Complications of endovascular repair for thoracic and abdominal aortic aneurysm: an imaging spectrum.

Endovascular stent-graft implantation is an alternative to conventional open surgery for the treatment of aortic aneurysm. Forty-nine consecutive patients with aortic aneurysm (thoracic, n = 17; infrarenal, n = 32) were treated with endovascular stent-graft implantation. Complications occurred in 25 patients (two patients had two complications): endoleak (n = 13), graft thrombosis (n = 5), graft kinking (n = 2), pseudoaneurysm caused by graft infection (n = 1), graft occlusion (n = 1), shower embolism (n = 1), perforation of mural thrombus by means of inadvertent penetration of delivery system (n = 1), colon necrosis (n = 1), aortic dissection (n = 1), and hematoma at the arteriotomy site (n = 1). Imaging findings were analyzed for spiral computed tomography, plain abdominal radiography, transesophageal echocardiography, and digital subtraction angiography. Since some of these complications are fatal, radiologists need to instantly and accurately recognize them. Awareness and understanding of possible complications should help ensure a safe, successful procedure.     

Complete ten-year follow-up after endovascular abdominal aortic aneurysm repair: survival and causes of death

Purpose

To analyze the hazard and causes of death after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms during a complete ten year follow-up.

Methods

This is a retrospective clinical study of 130 consecutive patients undergoing EVAR between 1995 and 1998. One-hundred twenty-one patients (93.1%) were treated with first-generation stentgrafts and nine patients (6.9%) received second-generation devices. All patients completed a follow-up of at least 10 years, unless death occurred before then. Time and causes of death were provided by the Austrian central register of deaths.

Results

The median follow-up was 7.6 years, and the 130 patients had 968.5 person-years of follow-up. The ten-year mortality rate was 62.3%. Cardiovascular events were the most frequent causes of death, with a 3.9 incidence rate per 100 person-years. Cancer death and death due to other causes occurred in 2.1 and 1.8 cases per 100 person-years, respectively. Lethal late aneurysm rupture happened in 4.6% (n = 6), which corresponds to an annual incidence rate of 0.6 per 100 person-years. All of those patients had been treated with first-generation devices.

Conclusions

Cardiovascular events were the most frequent cause of death after EVAR, followed by malignancy and other diseases. The risk of dying from secondary rupture was clearly lower than that of death due to other reasons during ten years after EVAR, even in patients with first-generation stentgrafts.     

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.     

Lessons learnt from the EUROSTAR registry on endovascular repair of abdominal aortic aneurysm repair.

OBJECTIVE: The EUROSTAR project is a multicentred database of the outcome of endovascular repair of infra-renal aortic aneurysms. To date 92 European centres of vascular surgery have contributed. The purpose of the article here is to review the medium term (up to 4 years) results of endovascular aneurysm repair as reported to Eurostar. PATIENTS AND METHODS: Patients intended for endovascular aneurysm repair were notified to the EUROSTAR Data Registry Centre before treatment in order to eliminate bias due to selective reporting. The following data was collected on all patients: (1) their demographic details and the anatomical characteristics of their aneurysms, (2) details of the endovascular device used, (3) procedural complications and the immediate outcome, (4) results of contrast enhanced CT imaging at 3, 6, 12 and 18 months after operation and at yearly intervals thereafter, (5) all adverse events. Life table analysis was performed to determine the cumulative rates of: (1) death from all causes, (2) secondary intervention. Risk factors for rupture and late conversion were identified by regression analysis. RESULTS: By July 2000, 2862 patients had been registered and their median duration of follow-up was 12 mo (range 0-72). Successful deployment was achieved in 2812 patients with a perioperative (30 day) mortality of 2.9%. In 2464 patients enrolled by March 2000 late rupture of the aneurysm occurred in 14 patients for an annual cumulative rate of 1%. The significant factors were proximal type I endoleak (P=0.001), midgraft (type III) endoleak (P=0.001), graft migration (P=0.001) and post-operative kinking of the endograft (P=0.001). Forty-one patients had late conversion to open repair for an annual cumulative rate (risk) of approximately 2.1%. Risk factors (indications) for late conversion were: proximal type I endoleak (P=0.001), midgraft (type III) endoleak (P=0.001), type II endoleak (P=0.003), graft migration (P=0.001), graft kinking (P=0.001) and distal type I endoleak (P=0.001). CONCLUSIONS: Endovascular repair of infra-renal aortic aneurysms using the first and second-generation devices that predominated in this study was associated with a risk of late failure of 3% per year, based upon an analysis of observed primary endpoints of rupture and conversion. Eurostar continues to provide responsible evaluation of the technique for the benefit of both physicians and the industry.     

不使用造影剂的腹主动脉瘤腔内隔绝术

目的：探讨一种不使用造影剂的腹主动脉瘤（AAA）腔内隔绝术（EVE），治疗合并肾功能不全的AAA患者。方法：对3例合并肾功能不全的AAA患者在不使用造影剂条件下实施AAA EVE，并对术前评估内容进行分析。结果：3例患者手术均获成功，2例采用分叉型移植物，1例采用直型移植物。术后随访结果表明，动脉瘤被完全隔绝，无内漏，瘤腔内血栓形成；移植物内血流通畅，周围无异常血充。结论：选择近端瘤颈较长的患者，术前对肾动脉及髂内动脉开口位置等指标进行准确评估，不使用造影剂同样可以完成AAA EVE。     

Renal dysfunction after abdominal or thoracic endovascular aortic aneurysm repair: incidence and risk factors

Purpose

To determine the incidence and risk factors of renal dysfunction after abdominal endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR).

Materials and methods

The study consisted of 227 patients treated with EVAR and 90 with TEVAR for aortic aneurysms. Parameters, including patients’ background factors, preoperative renal function, contrast dose and aortic wall irregularity on CT images were assessed in relation to postoperative renal dysfunction.

Results

Deterioration of renal function was observed in 33 of 218 patients (15.1%) after EVAR and in 7 of 79 (8.9%) patients after TEVAR. Hemodialysis was required in one patient after EVAR. In EVAR, renal dysfunction correlated with age (p = 0.034) and occlusion of accessory renal artery (p = 0.0001). In TEVAR, renal dysfunction correlated with age (p = 0.021), contrast dose (p = 0.042) and irregularity of the descending aortic wall (p = 0.023). In a multiple regression analysis, postoperative renal dysfunction was correlated with occlusion of accessory renal artery (p = 0.0003) after EVAR, and age (p = 0.02), contrast dose (p = 0.026) and irregularity of the descending aortic wall (p = 0.042) after TEVAR.

Conclusion

Occlusion of accessory renal artery in EVAR, and age, contrast dose and irregularity of the descending aortic wall in TEVAR were considered to be predictors of postoperative renal dysfunction.