Anatomical risk factors for proximal perigraft endoleak and graft migration following endovascular repair of abdominal aortic aneurysms

Correlation Between Calcium Scoring and Abdominal Aortic Aneurysm Endovascular Repair Outcomes

OBJECTIVES

Endovascular aneurysm repair, though minimally invasive and has the benefit of relatively low perioperative complication rates, it is associated with significant long term reintervention rates related to endoleaks. Several variables have been studied to predict the outcomes of endovascular aneurysm repair, 1 of which is the calcium burden of the vasculature. This prompted us to study the association between calcium burden measured by the standardized Agatston scoring system and the outcomes of Endovascular aneurysm repair.

METHODS

This is a retrospective study of patients who underwent Endovascular aneurysm repair from 2008 to 2020 at our institution and who had a non-contrast computerized tomography scan preoperatively, accounting for 87 patients. The calcium burden of the vasculature was measured by the Agatston scoring system allowing for better reproducibility, and the outcome variables included mortality and endoleaks.

RESULTS

Patients with higher median total calcium scores (≥12966.9) had significantly lesser survival (79.8% vs 52.3% (P = .002) at five years compared to patients with lower median total calcium score (<12966.9). Also, patients with type 2 endoleaks had higher calcium scores in above the aneurysm level ((1591.2 vs 688.2), P = .05)) compared to patients with no type 2 endoleaks.

CONCLUSION

Calcium score assigned using a standardized Agatston scoring system can be used as a predictor of mortality risk assisting in deciding the treatment of choice for patients.

Computational prediction of proximal sealing in endovascular abdominal aortic aneurysm repair with unfavorable necks

BACKGROUND AND OBJECTIVE

Endovascular aortic aneurysm repair (EVAR) has become the standard treatment for abdominal aortic aneurysms in most centers. However, proximal sealing complications leading to endoleaks and migrations sometimes occur, particularly in unfavorable aortic anatomies and are strongly dependent on biomechanical interactions between the aortic wall and the endograft. The objective of the present work is to develop and validate a computational patient-specific model that can accurately predict these complications.

METHODS

Based on pre-operative CT-scans, we developed finite element models of the aorta of 10 patients who underwent endovascular aortic aneurysm repair, 7 with standard morphologies and 3 with unfavorable anatomies. We simulated the deployment of stent grafts in each aorta by solving mechanical equilibrium with a virtual shell method. Eventually we compared the actual stent ring positions from post-operative computed-tomography-scans with the predicted simulated positions.

RESULTS

A successful deployment simulation could be performed for each patient. Relative radial, transverse and longitudinal deviations were 6.3 ± 4.4%, 2.5 ± 0.9 mm and 1.4 ± 1.1 mm, respectively.

CONCLUSIONS

The numerical model predicted accurately stent-graft positions in the aortic neck of 10 patients, even in complex anatomies. This shows the potential of computer simulation to anticipate possible proximal endoleak complications before EVAR interventions.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Brazilian Society for Angiology and Vascular Surgery guidelines on abdominal aortic aneurysm

The Brazilian Society of Angiology and Vascular Surgery, through the Guidelines Project, presents new Abdominal Aortic Aneurysm Guidelines, on the subject of care for abdominal aortic aneurysm patients. Its development prioritized descriptive guidelines, using the EMBASE, LILACS, and PubMed databases. References include randomized controlled trials, systematic reviews, meta-analyses, and cohort studies. Quality of evidence was evaluated by a pair of coordinators, aided by the RoB 2 Cochrane tool and the Newcastle Ottawa Scale forms. The subjects include juxtarenal aneurysms, infected aneurysms, and new therapeutic techniques, especially endovascular procedures. The current version of the guidelines include important recommendations for the primary topics involving diagnosis, treatment, and follow-up for abdominal aortic aneurysm patients, providing an objective guide for medical practice, based on scientific evidence and widely available throughout Brazil.

Diminishing Endograft Apposition during Follow-Up Is an Important Indicator of Late Type 1a Endoleak after Endovascular Aneurysm Repair

Late type 1a endoleaks (T1aELs) after endovascular aneurysm repair (EVAR) are hazardous complications which should be avoided. This study investigated the evolution of the shortest apposition length (SAL) post-EVAR and hypothesised that a declining apposition during follow-up may be an indicator of T1aEL development. Patients with a late T1aEL were selected from a consecutive multicentre database. For each T1aEL patient, the preoperative computed tomography angiography (CTA), first postoperative CTA, and pre-endoleak CTA were analysed. T1aEL patients were matched 1:1 to uncomplicated controls, based on endograft type and follow-up duration. Anatomical characteristics and endograft dimensions, including the post-EVAR SAL, were measured. Included were 28 patients with a late T1aEL and 28 matched controls. The SAL decreased from 11.2 mm (5.6-20.6 mm) to 3.9 mm (0.0-11.4 mm) in the T1aEL group (p = 0.006), whereas an increase in SAL was seen in the control group from 21.3 mm (14.1-25.8 mm) to 25.4 mm (19.0-36.2 mm; p = 0.015). On the pre-endoleak CTA, 18 patients (64%) in the T1aEL group had a SAL < 10 mm, and one (4%) patient in the control group had a SAL < 10 mm on the matched CTAs. Moreover, three mechanisms of decreasing sealing zone were identified, which might be used to determine optimal imaging or reintervention strategies. Diminishing SAL < 10 mm is an indicator for T1aEL during follow-up, it is imperative to include apposition analysis during follow-up.

Early Clinical Outcomes of the Active Seal Technology of the AFX Endovascular Aortic Aneurysm System With the VELA Cuff for Patients With a Conical Proximal Neck

PURPOSE

To evaluate the efficacy of the Active Seal technology employed in the AFX endovascular aortic aneurysm system (AFX), during endovascular aneurysm repair (EVAR) in patients with abdominal aortic aneurysms (AAAs) having a conical proximal neck.

MATERIALS AND METHODS

A retrospective analysis of the EVAR for AAA with a conical proximal neck using the AFX was performed at 17 Japanese hospitals between January 2016 and August 2020. The conical proximal neck was defined as a cone-shaped proximal neck, with more than 10% diameter increase within a 15 mm length at the proximal landing zone. All anatomical analyses were performed in the core laboratory, and cases with parallel walls within the proximal neck adequate for the landing zone were excluded from the study.

RESULTS

This study included 53 patients, but only 39 patients (mean age, 76.6 ± 6.7 years; 87.0% males; mean aneurysm diameter, 52.0 ± 8.0 mm) were analyzed after being characterized as having a pure conical neck by the core laboratory. The mean proximal neck diameters at the lower renal artery and proximal edge of the aneurysm were 20.0 ± 2.9 mm and 27.5 ± 4.9 mm, respectively. The mean proximal neck length was 21.5 ± 6.0 mm. Instructions for use violations other than the conical neck were observed in 15 patients (38.5%). The VELA cuff was used in all cases; however, additional proximal cuff was required in 9 more cases (23.1%). The Active Seal technology was able to significantly extend the proximal sealing zone from 21.5 ± 6.0 to 26.0 ± 12.2 mm (p = .047). Thirty-six patients completed the 12-month follow-up (one patient was lost to follow-up, and 2 patients died from causes unrelated to the aneurysm), and there were no type-1a and 3 endoleaks with only one reintervention (2.6%) related to type 1b endoleak in the 12-month period. Furthermore, there was no significant enlargement of the proximal neck diameter at 12 months (at 1 month: 20.6 ± 3.4 mm and at 12 months: 21.3 ± 3.8 mm; p = .420).

CONCLUSION

The Active Seal technology of the AFX significantly extended the proximal seal zone and no type-1a endoleak and proximal neck dilation was observed in patients with conical proximal neck at 12 months.

EndoSuture aneurysm repair versus fenestrated aneurysm repair in patients with short neck abdominal aortic aneurysm

OBJECTIVE

The aim of this study was to compare midterm results of EndoAnchors in EndoSuture aneurysm repair (ESAR) versus fenestrated endovascular aneurysm repair (FEVAR) in short neck abdominal aortic aneurysm (AAA).

METHODS

All patients who underwent an ESAR procedure for a short neck AAA at our center between September 2017 and May 2020 were considered for analysis. To form the control group, preoperative computed tomography angiography of patients who underwent FEVAR for juxtarenal AAA between April 2012 and May 2020 were reviewed and patients who met short neck criteria selected. A propensity-matched score on neck length and neck diameter was calculated, resulting in 18 matched pairs. AAA shrinkage, type Ia endoleaks (EL), AAA-related reinterventions, and AAA-related deaths were compared.

RESULTS

The median AAA diameter was 54 mm (interquartile range [IQR], 52-61 mm) versus 58 mm (IQR, 53-63 mm) with a median neck length of 8 mm (IQR, 6-12 mm) vs 10 mm (IQR, 6-13 mm) in ESAR and FEVAR patients, respectively. Technical success was 100% in both groups. Procedural success was 94% in the ESAR group versus 100% in the FEVAR group. The median procedure duration was 138 mm (IQR, 113-182 mm) vs 240 mm (IQR, 199-293 mm) ( P < .001) and the median length of stay was 2 days (IQR, 2-3 days) vs 7 days (IQR, 6-7 days) (P < .001) in ESAR and FEVAR patients, respectively. No major hospital complications were observed in ESAR patients compared with two in FEVAR patients (11%) with one transient acute kidney injury and one transient paraplegia. The median follow-up was 23 months (IQR, 19-33 months) vs 36 months (IQR, 22-57 months) with 67% versus 61% AAA shrinkage in the ESAR and FEVAR groups, respectively (P = .73). No type Ia EL, proximal neck-related reinterventions, or AAA-related deaths were observed in either group. No AAA-related reintervention was observed in the ESAR group versus three reinterventions in the FEVAR group (P = .23).

CONCLUSIONS

ESAR seems to be a safe technique with no major postoperative complications or reinterventions observed during follow-up. It seems to offer similar midterm results as FEVAR in terms of type Ia EL, aneurysm shrinkage, and aneurysm-related mortality. ESAR seems to be a good off-the-shelf alternative to FEVAR in case of technical constraints.

The intervention seasons of thoracic endovascular aortic repair impacted the outcomes for patients with type B aortic dissection

Purpose

The objective of this research was to investigate whether seasonal variations influence the outcomes of type B aortic dissection (TBAD) patients with thoracic endovascular aortic repair (TEVAR).

Patients and methods

From 2003 to 2020, a retrospective cohort study was performed, which included 1,123 TBAD patients who received TEVAR. Medical records were used to gather data on baseline characteristics. Outcomes including all-cause mortality and aortic-related adverse events (ARAEs) were tracked and analyzed.

Results

Of the 1,123 TBAD patients in this study, 308 received TEVAR in spring (27.4%), 240 cases in summer (21.4%), 260 cases in autumn (23.2%), and 315 cases in winter (28.0%). Patients in the autumn group had a significantly lower risk of 1-year mortality than those in the spring group (hazard ratio: 2.66, 95% confidence interval: 1.06-6.67, p = 0.037). Kaplan-Meier curves revealed that patients who underwent TEVAR in autumn had a lower risk of 30-day ARAEs (p = 0.049) and 1-year mortality (p = 0.03) than those in spring.

Conclusion

This study confirmed that TEVAR operated in autumn for TBAD was associated with a lower risk of 30-day ARAEs and 1-year mortality than in spring.

Is Evar Feasible in Challenging Aortic Neck Anatomies? A Technical Review and Ethical Discussion

Background: Endovascular aneurysm repair (EVAR) has become an accepted alternative to open repair (OR) for the treatment of abdominal aortic aneurysm (AAA) despite “hostile” anatomies that may reduce its effectiveness. Guidelines suggest refraining from EVAR in such circumstances, but in clinical practice, up to 44% of EVAR procedures are performed using stent grafts outside their instruction for use (IFU), with acceptable outcomes. Starting from this “inconsistency” between clinical practice and guidelines, the aim of this contribution is to report the technical results of the use of EVAR in challenging anatomies as well as the ethical aspects to identify the criteria by which the “best interest” of the patient can be set. Materials and Methods: A literature review on currently available evidence on standard EVAR using commercially available endografts in patients with hostile aortic neck anatomies was conducted. Medline using the PubMed interface and The Cochrane Library databases were searched from 1 January 2000 to 6 May 2021, considering the following outcomes: technical success; need for additional procedures; conversion to OR; reintervention; migration; the presence of type I endoleaks; AAA-related mortality rate. Results: A total of 52 publications were selected by the investigators for a detailed review. All studies were either prospective or retrospective observational studies reporting the immediate, 30-day, and/or follow-up outcomes of standard EVAR procedures in patients with challenging neck anatomies. No randomized trials were identified. Fourteen different endo-grafts systems were used in the selected studies. A total of 45 studies reported a technical success rate ranging from 93 to 100%, and 42 the need for additional procedures (mean value of 9.04%). Results at 30 days: the incidence rate of type Ia endoleak was reported by 37 studies with a mean value of 2.65%; 31 studies reported a null migration rate and 32 a null conversion rate to OR; in 31 of the 35 studies that reported AAA-related mortality, the incidence was null. Mid-term follow-up: the incidence rate of type Ia endoleak was reported by 48 studies with a mean value of 6.65%; 30 studies reported a null migration rate, 33 a null conversion rate to OR, and 28 of the 45 studies reported that the AAA-related mortality incidence was null. Conclusions: Based on the present analysis, EVAR appears to be a safe and effective procedure—and therefore recommendable—even in the presence of hostile anatomies, in patients deemed unfit for OR. However, in order to identify and pursue the patient’s best interest, particular attention must be paid to the management of the patient’s informed consent process, which—in addition to being an essential ethical-legal requirement to legitimize the medical act—ensures that clinical data can be integrated with the patient’s personal preferences and background, beyond the therapeutic potential of the proposed procedures and what is generically stated in the guidelines.

Long-term outcomes of open and endovascular abdominal aortic repair in younger patients

OBJECTIVES

To evaluate long-term results in abdominal aortic aneurysm (AAA) surgery by either open (OAR) or endovascular (EVAR) repair in patients under 70 years of age.

METHODS

A retrospective analysis of a prospectively collected database of patients with age under 70 years old undergoing elective infrarenal AAA surgery between 2010 and 2018 was performed. The study population was divided into two groups: OAR and EVAR. The primary end-points were overall survival and aneurysm-related death, while secondary outcomes were need for reintervention and development of minor and major complications.

RESULTS

191 patients younger than 70 years old treated for elective AAA surgery were enrolled: 157 OAR (98% males, mean age 65 ± 4 years) and 34 EVAR (94% males, mean age 66 ± 4 years). Hospital stay, 30-day mortality and need for reintervention were similar; OAR population presented higher incidence of postoperative major complications (18% vs 2.9%; p .01) while minor complications were 32% in OAR vs 21% in EVAR group (p .08). Median follow-up was 69 months for OAR (IQR 53 months) vs. 79 months (IQR 51 months) for EVAR (p .9): long-term AAA-related reinterventions were more frequent after EVAR (1.9% OAR vs. 17% EVAR; p .01) while AAA-related long-term mortality was similar in both sugroups (1.3% OAR and 3% EVAR; p .8). At univariate analysis a higher risk of reintervention was reported for conical necks in EVAR group (p .03) and for the concomitant presence of iliac aneurysms in both groups (p .01).

CONCLUSIONS

In our population, the presence of a conical neck is an independent predictor of EVAR failure and late reintervention, while it does not play a significant role in OAR group. For this reason, in such cases, open surgery must be considered as the first option in younger patients with a long-life expectancy.

Fully Ultrasound-Assisted Endovascular Aneurysm Repair (EVAR): preliminary report

BACKGROUND

Reducing fluoroscopy times and iodine contrast administration during endovascular exclusion (EVAR) of infrarenal aortic aneurysms (AAA) remains a challenge. The purpose of this study was to evaluate the preliminary results of a fully ultrasound-assisted EVAR without iodine contrast administration.

METHODS

Twentyseven consecutive patients, underwent an elective IVUS-assisted EVAR with final CEUS control of correct aneurysm exclusion. In no case intraprocedural injection of iodine contrast medium was performed. The primary study's endpoints were the overall duration of the procedure, duration of fluoroscopy, cumulative radiation dose, the length of intraoperative CEUS control and the comparison of findings between intraoperative CEUS and CT-scan at one month.

RESULTS

Mean duration of the procedure was 130 ± 35 minutes. Overall duration of fluoroscopy was 22 ± 18 minutes. Mean radiation dose was 66 mGy (range, 24 - 82). The mean length of CEUS final control was 8 ± 2 minutes. No type I or type III endoleak was detected either at CEUS or at angio-CT scan at one month from EVAR. CEUS revealed a type II endoleak in 6 patients (22%) , compared to 9 type II endoleaks (33%) detected at angio-CT scan one month after the procedure (p = 0.5).

CONCLUSIONS

Fully ultrasound (IVUS and CEUS) -assisted EVAR is safe, feasible and reliable, completely eliminating the need for iodine contrast medium and reducing the radiation exposure for both patients and surgeons.

Hybrid Approach with Angiography and Limited Open Exposure to Treat Type Ia Endoleaks after Endovascular Aortic Aneurysm Repair

BACKGROUND

Type Ia endoleaks after endovascular aortic repair (EVAR) almost always mandate secondary percutaneous reinterventions. Several patients, however, will require conversion to open surgical repair with complete graft explant, which is associated with significant morbidity and mortality. We herein present 3 cases of hybrid surgical repair for type Ia endoleaks, using a limited open exposure for proximal stent graft edge revision to achieve graft preservation and effective aneurysm sac exclusion.

METHODS

Angiography was used to confirm type Ia endoleak in 3 patients (2 males) who had previous EVAR between October 2017 and October 2019. Time to the endoleak after the index EVAR was immediate in 1 patient during repair of a ruptured aneurysm, 2 months in 1 patient and 2 years in 1 patient. The aorta was exposed through a limited transabdominal (n = 1) or retroperitoneal (n = 2) approach and circumferential aortic control was achieved below the renal arteries. A row of interrupted horizontal mattress sutures of 3-0 polypropylene reinforced with Teflon pledgets was placed along the aortic neck circumference. Multi-planar angiography was then repeated to verify the absence of sac filling and successful type Ia endoleak exclusion. Follow-up abdominal duplex was obtained for all 3 patients after discharge to monitor the stent graft and confirm endoleak resolution. Furthermore, there were no instances of acute renal failure.

RESULTS

In the period of review, 77 patients underwent EVAR. In the 3 patients described, we were able to achieve complete aneurysm sac exclusion and stent graft preservation in all cases. Follow-up imaging was available on 2 patients at 4-6 weeks after surgery demonstrating sustained exclusion of the endoleak. Two patients died during follow-up: one from a myocardial infarction 7 weeks after surgery and one from metastatic lung cancer at 8 months after surgery. Follow up duplex imaging at one year on the single survivor demonstrated sac shrinkage and absence of endoleak.

CONCLUSIONS

Type Ia endoleaks represent a significant source of morbidity and mortality after EVAR and typically require repair to avoid aneurysm rupture. Our use of limited proximal revision without explant provides an alternative approach to resolve the endoleaks while reducing the magnitude of physiological stress when compared to an open explant. It represents a feasible option for high-risk patients.

Peroperative Intravascular Ultrasound for Endovascular Aneurysm Repair versus Peroperative Angiography: A Pilot Study in Fit Patients with Favorable Anatomy

BACKGROUND

The aim of this study was to compare intravascular ultrasound (IVUS) assistance for endovascular aortic aneurysm repair (EVAR) to standard assistance by angiography.

METHODS

From June 2015 to June 2017, 173 consecutive patients underwent EVAR. In this group, 69 procedures were IVUS-assisted with X-ray exposure limited to completion angiography for safety purposes because an IVUS probe does not yet incorporate a duplex probe (group A), and 104 were angiography-assisted procedures (group B). All IVUS-assisted procedures were performed by vascular surgeons with basic duplex ultrasound (DUS) training. The primary study endpoints were mean radiation dose, duration of fluoroscopy, amount of contrast media administered, procedure-related outcomes, and renal clearance expressed as the glomerular filtration rate (GFR) before and after the procedure. Secondary endpoints were operative mortality, morbidity, and arterial access complications.

RESULTS

Mean duration of fluoroscopy time was significantly lower for IVUS-assisted procedures (24 ± 15 min vs. 40 ± 30 min for angiography-assisted procedures, P < 0.01). Moreover, mean radiation dose (Air KERMA) was significantly lower in IVUS-assisted procedures (76m Gy [44-102] vs. 131 mGy [58-494]), P < 0.01. IVUS-assisted procedures required fewer contrast media than standard angiography-assisted procedures (60 ± 20 mL vs. 120 ± 40 mL, P < 0.01). The mean duration of the procedure was comparable in the two groups (120 ± 30 min vs. 140 ± 30 min, P = 0.07). No difference in renal clearance before and after the procedure was observed in either of the two groups (99.0 ± 4/97.8 ± 2 mL/min in group A and 98.0 ± 3/97.6 ± 5 mL/min in group B) (P = 0.28). The mean length of follow-up was nine months (6-30 months). No postoperative mortality, morbidity, or arterial access complications occurred. No type 1 endoleak was observed. Early type II endoleaks were observed in 21 patients (11%), 12 in the angiography-assisted group (11%) and nine in the IVUS-assisted group (12%). They were not associated with sac enlargement ≥5 mm diameter and therefore did not require any additional treatment.

CONCLUSIONS

Compared with standard angiography-assisted EVAR, IVUS significantly reduces renal load with contrast media, fluoroscopy time, and radiation dose while preserving endograft deployment efficiency. Confirmation from a large prospective study with improved IVUS probes will be required before IVUS-assisted EVAR alone can become standard practice.

Outcomes of endovascular treatment of endoleak type Ia after EVAR: a systematic review of the literature

INTRODUCTION

Endovascular repair of infra-renal aortic aneurysm (EVAR) has become treatment of choice. However, individuals undergoing EVAR have a high re-intervention rate. The aim of this study is to evaluate the current endovascular treatment modalities of endoleak type Ia (ET Ia) treatment after EVAR and their outcome.

EVIDENCE ACQUISITION

A systematic review and meta-analysis was performed. MEDLINE, EMBASE and Cochrane databases were searched with PRISMA methodology for studies reporting on endovascular treatment of ET Ia after EVAR. Studies presenting treatment of intra-operative ET Ia were excluded.

EVIDENCE SYNTHESIS

Two international registries, fourteen non-randomized retrospective and twelve case-report studies were included reporting on 356 patients. Reported endovascular techniques included fenestrated-, branched-, chimney EVAR, endovascular sealing (EVAS), endoanchors, embolization techniques, cuff and/or "giant" Palmaz stents. Technical success rate ranged from 90% to 100%, with intra-operative mortality rate of 0%. During early period, persistence of ET Ia was 3.4% (9/262) and the re-intervention rate was 3.5% (8/227). The 30-day mortality rate was 2% (7/356). Mean follow-up was 22.4 months±18. Presence of ET Ia was 5.9% (21/356), and the reintervention rate was 5.1% (18/349). The mortality rate was 13% (26/203), while the primary patency rate of TVs ranged from 94.3% to 100%.

CONCLUSIONS

A multitude of techniques for endovascular repair for ET Ia exists. No strong evidence supports one specific technique. The early and mid-term outcomes are encouraging in terms of ET Ia resolution, mortality and morbidity rates.

Early results with the custom-made Fenestrated Anaconda aortic cuff in the treatment of complex abdominal aortic aneurysm

OBJECTIVE

The objective of this study was to investigate the feasibility of a specific custom-made fenestrated aortic cuff in the treatment of complex abdominal aortic aneurysms (AAAs).

METHODS

Between 2013 and 2016, a total of 57 custom-made Fenestrated Anaconda (Vascutek, Inchinnan, Scotland, UK) aortic cuffs were placed in 38 centers worldwide. All centers were invited to participate in this retrospective analysis. Postoperative and follow-up data included the presence of adverse events, necessity for reintervention, and renal function.

RESULTS

Fifteen clinics participated, leading to 29 cases. Median age at operation was 74 years (interquartile range [IQR], 71-78 years); five patients were female. Two patients were treated for a para-anastomotic AAA after open AAA repair, 19 patients were treated because of a complicated course after primary endovascular AAA repair, and 8 cases were primary procedures for AAA. A total of 76 fenestrations (mean, 2.6 per case) were used. Four patients needed seven adjunctive procedures. Two patients underwent conversion, one because of a dissection of the superior mesenteric artery and one because of perforation of a renal artery. Median operation time was 225 minutes (IQR, 150-260 minutes); median blood loss, 200 mL (IQR, 100-500 mL); and median contrast volume, 150 mL (IQR, 92-260 mL). Primary technical success was achieved in 86% and secondary technical success in 93%. The 30-day morbidity was 7 of 29 with a mortality rate of 4 of 29. Estimated glomerular filtration rate remained unchanged before and after surgery (76 to 77 mL/min/m²). Between preoperative and median follow-up of 11 months, estimated glomerular filtration rate was reduced statistically significantly (76 to 63 mL/min/m²). During follow-up, 9 cases had an increase in aneurysm sac diameter (5 cases >5 mm); 14 cases had a stable or decreased aneurysm sac diameter; and in 2 cases, no aneurysm size was reported. No type I endoleak was reported, and two cases with a type III endoleak were treated by endovascular means during follow-up. Survival, reintervention-free survival, and target vessel patency at 1 year were 81% ± 8%, 75% ± 9%, and 99% ± 1%, respectively. After 2 years, these numbers were 81% ± 8%, 67% ± 11%, and 88% ± 6%, respectively. During follow-up, the two patients with a type III endoleak needed endograft-related reinterventions.

CONCLUSIONS

Treatment with this specific custom-made fenestrated aortic cuff is feasible after complicated previous (endovascular) aortic repair or in complex AAAs. The complexity of certain AAA cases is underlined in this study, and the Fenestrated Anaconda aortic cuff is a valid option in selected cases in which few treatment options are left.

Endovascular Aneurysm Repair in Patients with Conical Neck Anatomy

PURPOSE

Cone shape neck is regarded as non-instruction for use (IFU) in most commercial stent graft. However, in real practice, liberal application of endovascular aneurysm repair (EVAR) for outside of IFU happens. We investigate non-adherence to conical neck anatomy in terms of early aneurysmal exclusion results.

MATERIALS AND METHODS

From January 2010 to December 2013, 105 patients with abdominal aortic aneurysm (AAA) underwent EVAR in Daegu Catholic University Medical Center. Among them, 38 patients (36.2%) had AAA with conical neck. We investigated the clinical characteristics of patients and the details of conical neck. We also analyzed the clinical results, such as endoleak, migration, procedure failure, perioperative mortality, and admission duration between conical neck and non-conical neck.

RESULTS

The maximum diameter of AAA was larger (60.95 mm vs. 52.68 mm, P=0.016) and the infrarenal neck length was shorter (25.07 mm vs. 38.13 mm, P=0.000) in conical neck group. During the procedure, type Ia endoleak occurred more in conical neck group (23.7% vs. 6.0%, P=0.013) and it could be successfully solved with additional adjunctive treatments, such as balloon or Palmaz stent. Although there was no statistical significance, mortality was higher and admission duration was longer in the conical neck (15.8% vs. 6.0%, 16.62±13.12 days vs. 13.03±13.13 days). Mean follow-up duration was 319.2±366.45 days. Successful aneurysmal exclusion was achieved.

CONCLUSION

The presence of conical neck may not be a contraindication for EVAR. However, conical neck requires careful observation for additional adjunctive treatments because it increases the risk of type Ia endoleak.

Kilt Technique as an Angle Modification Method for Endovascular Repair of Abdominal Aortic Aneurysm with Severe Neck Angle

PURPOSE

Kilt technique can be useful for overcoming the severe angle in endovascular abdominal aortic repair. Thus, we investigate the utility of the Kilt technique as an angle modification method.

METHODS

This study included 16 patients with abdominal aortic aneurysm having severe neck angle (over 60°). Of these, eight were treated using Kilt technique, whereas the remaining eight were by the conventional endovascular method. We investigated the pre- and post-procedural differences in neck angle between the two groups using aortic computed tomography (CT) angiography.

RESULTS

Mean pre-procedural neck angles in the conventional group and the Kilt group were 70° ± 13° and 93° ± 14° (p = 0.007) and supra-renal neck angles were 54° ± 16° and 89° ± 26°, respectively (p = 0.016). However, the angle differences disappeared between the two groups after the procedure. Consequently, the Kilt group showed greater angle change than the conventional group (p value for ∆ supra-renal angle and ∆ neck angle were 0.015 and 0.021, respectively). There was no type 1 endoleak during 16 ± 16 months of CT follow-up.

CONCLUSION

Kilt technique may be an effective tool for modifying the neck angle without leaving increased risk of type 1 endoleak in this subset of patients.

Thrombus and Calcium in Aortic Aneurysm Necks: Validation of a Scoring System in a Dutch Cohort Study

This study was conducted to validate a proposed classification system on the characteristics of the abdominal aortic aneurysm neck. The cohort comprised 100 consecutive patients who underwent open or endovascular aneurysm repair. Aneurysm neck characteristics of diameter, calcium, thrombus, and angulation were reviewed. The presence of calcium at the aortic aneurysm wall was associated with lower body mass index. Thrombus was found in 52% of the patients. Hypertension was correlated with the presence of aortic wall thrombus. At the renal artery level, angulation was anterior in 56%, right lateral in 39%, and left lateral in 27%. At the origin of the aneurysm, angulation was posterior in 76%, right lateral in 46%, and left lateral in 42%. A wide variety in these characteristics was found. A scoring system allows comparison of patient characteristics in studies describing the clinical outcome of endovascular aneurysm repair and should be included in study reports.

Most Patients with Abdominal Aortic Aneurysm Are Not Suitable for Endovascular Repair Using Currently Approved Bifurcated Stent-Grafts

Strict morphologic criteria must be used for patient selection to achieve durable success with endovascular aortic aneurysm repair (EVAR). The goal of this study was to assess morphologic suitability (MS) of abdominal aortic aneurysms (AAAs) for 2 currently approved bifurcated stent grafts and identify reasons for exclusion from EVAR. The authors reviewed the electronic charts of 1,795 consecutive patients who were diagnosed as having AAA between January 1999 and July 2001 at their institution. Three hundred and twenty patients had an AAA with a diameter of =5.0 cm, measured on computed tomography (CT). The records of 301 patients, 254 men, 47 women, with a mean age of 74 years were available for review, and these patients constituted the study cohort. Criteria used for MS included a proximal neck length =15 mm; neck diameter between 18 and 26 mm; neck angulation =60°; common or external iliac artery (CIA or EIA) diameters of 7–16 mm and 8–13 mm, respectively, for AneuRx (Medtronic Ave, Santa Rosa, CA) and Ancure (Guidant Cardiac and Vascular Division, Menlo Park, CA) bifurcated grafts. AAAs were suitable for AneuRx device in 14% of patients (43 of 301; 95% CI = 11–19%) and for Ancure in 5% (16 of 301; 95% CI = 3.1–9%). The main reason for exclusion was an inadequate proximal aortic neck (73%). The neck was too short in 49.5%, too wide in 64% and badly angulated in 12% of the patients. Iliac artery morphology precluded EVAR with AneuRx and Ancure devices in 52% and 80%. Both CIAs were too wide for EVAR in 43% and 77%, respectively. When iliac artery diameter =20 mm was accepted, iliac suitability for AneuRx increased from 49% to 70% and overall suitability increased from 14% to 20%. When more permissive criteria were used for MS (neck length =10 mm, neck diameter =30 mm, CIA =20), 39% of patients became candidates for EVAR. More than three fourths of the patients with an AAA =5.0 cm in size, seen in a tertiary referral center, are morphologically not suitable for EVAR using 2 currently approved bifurcated endografts. The main reasons for exclusion are a short or wide proximal aortic neck. Considerable changes in size of the devices and in proximal attachment techniques have to occur before most AAAs will be suitable for EVAR.

Outcomes of Endovascular AAA Repair in Patients with Hostile Neck Anatomy Using Adjunctive Balloon-Expandable Stents

Hostile neck anatomy remains the predominant reason that patients are denied endovascular aneurysm repair (EVAR). We reviewed our experience of EVAR with use of prophylactic adjunctive proximal balloon-expandable stents in patients with hostile neck anatomy and adjunctive proximal balloon-expandable stents in patients with type I endoleaks. Of 140 patients who underwent EVAR between 2000 and 2004, we reviewed data for 19 patients in whom we used proximal balloon-expandable stents. By high-resolution computed tomography scan or angiography, hostile neck anatomy was classified as length <15 mm, neck diameters = 26 mm, circumferential thrombus at the proximal neck, angulated neck =60 degrees, and neck bulge or reverse taper necks. Patients were considered to have hostile anatomy if they met 1 or more of the above-cited criteria. All patients underwent AAA repair with commercially available endograft systems, Zenith (Cook, Bloomington, IN) and AneuRx (Medtronic/AVE, Minneapolis, MN). Balloon-expandable stents utilized included Cordis-Palmaz stents (17/19) and eV3 Max stents (2/19). Stents were deployed in the proximal graft with transrenal extension. AneuRx (18/19) and Zenith (1/19) endografts were used in all of the patients. Of the 19 patients, 15 had prophylactic stent placement for known hostile neck anatomy and 4 patients had stent placement for type I endoleak. Assisted primary technical success was achieved in all patients. Three patients had maldeployment of the endograft or proximal stent requiring additional endovascular interventions at the time of surgery. No endografts were deployed too low requiring stent placement. Procedure-related complications occurred in 2 of 19 patients. These included 1 operative death secondary to pneumonia and 1 patient who developed progressive renal failure. Short-term clinical success was achieved in 17 of 19 patients. Two patients required secondary interventions, 1 due to device migration with secondary conversion to open repair, and an endoleak, which, on angiogram, was a large type II endoleak successfully treated with coiling of the inferior mesenteric artery. One patient was observed to have a type II endoleak with no associated aneurysm enlargement. Short-term results suggest the use of prophylactic adjunctive balloon-expandable stents may decrease the incidence of secondary interventions related to hostile neck anatomy when used as an adjunctive measure with EVAR. Based on our experience, we feel EVAR may be offered to an expanded patient population with hostile neck anatomy with use of prophylactic balloon-expandable stents.

Custom-made Stent-Grafts for Aortic Aneurysm Repair Using Gianturco Z Stents and Woven Polyester: Healing in an Animal Model

The purpose of this study was to evaluate the healing at 6 months of aortic stent-grafts custom-made by using Z stents and woven polyester in an animal model. Stent-grafts were built by a published method using autoexpandable stainless steel stents continuously compiled with polyester sutures and covered with a woven polyester membrane. Fourteen stent-grafts of 3 different designs were deployed under fluoroscopic control into the thoracic and the abdominal aorta of 7 adult sheep. At 6 months, all the implants of the sheep that survived the implantation were angiographed and harvested for macroscopy and microscopy. All stentgrafts were implanted successfully and remained patent from then to the explantation procedure. All stent-grafts implanted among the 6 of 7 (86%) animals that survived after the implantation remained patent, stayed free from local complications, and did not migrate during more than 6 months. In all these cases during this period, the implant functioned as a satisfactory aortic substitute while the aortic segment containing the graft kept a normal structure. There was no adverse effects of the presence of the implant upon the aorta or the animal. Stent-grafts home-made according to the described methods gave results at 6 months in this animal model compatible with a safe clinical application among humans.

Device-Specific Resistance to in Vivo Displacement of Stent-Grafts Implanted with Maximum Iliac Fixation

Purpose:

To compare the in vivo device-specific downward displacement force of various externally supported endografts implanted with maximum iliac fixation.

Methods:

Twenty female sheep had aneurysms created with a graft patch in the infrarenal aorta. In 12 animals, a fully supported modular bifurcated stent-graft [AneuRx (n=4), Talent (n=4), or Zenith (n=4)] was deployed; in the other 8, a bifurcated aortic graft was surgically anastomosed to the infrarenal aorta. All grafts were displaced in vivo by applying downward traction to a guidewire brought out both femoral arteries. The peak force to cause initial stent-graft migration or disruption of the sutured anastomosis was recorded and compared.

Results:

There was no difference in animal size, aortic neck diameter or length, aneurysm size, or iliac artery diameter for animals receiving the AneuRx, Talent, or Zenith stent-grafts and those undergoing surgical repair. The mean length of iliac fixation was 31.0±0.3 mm, 30.8±0.5 mm, and 31.3±0.6 mm for the AneuRx, Talent, and Zenith devices, respectively (p=NS). Peak force to initiate migration was 30.2=5.5 N (range 25–38) for the AneuRx, 44.8±5.5 N (range 40–53) for the Talent, 46.7±5.4 N (range 38–55) for the Zenith, and 40.6±7.5 N (range 31–50) for the surgical anastomosis (p=0.01). There was no difference detected in the peak force to initiate migration between the suprarenally affixed Talent and Zenith stent-grafts and the surgical anastomosis (p=0.55).

Conclusion:

Devices with a suprarenal component require significantly greater force to cause downward displacement compared to infrarenal devices. The force required to displace a suprarenal device with maximal iliac fixation was equivalent to the force required to disrupt a surgical anastomosis.

Apparatus for Comparison of Pullout Forces for Various Thoracic Stent Grafts at Varying Neck Angulations and Oversizes

BACKGROUND

The purpose of this study is to provide an apparatus for comparison of pullout forces for various thoracic stent grafts at varying neck angulations and oversizes.

METHODS

An in vitro platform capable of performing pullout tests was used on stent grafts in angulated silicone tubes designed for this study (0°, 45°, 90°, and 135° with a 32-mm inner diameter) in a temperature-controlled chamber (37 ± 2°C). Three commercial stent grafts with sizes commonly used in Taiwan (Valiant: 34, 36, 38, and 40 mm; Zenith TX2: 34, 36, 38, and 40 mm; and TAG: 34, 37, and 40 mm) were used, and each size was tested 8 times for each angulation condition.

RESULTS

The mean dislodgement forces (DFs) at 0° angulation within 10-20% oversize were approximately 22.7, 9.6, and 9.0 N for the Valiant, Zenith TX2, and TAG devices, respectively, whereas the mean DFs decreased by 46%, 38%, and 50% to 12.3, 5.9, and 4.5 N when the angulation reached 135°. Regression analysis shows that neck angulation was a significant factor for the Valiant and Zenith TX2 devices (P < 0.0001 and P < 0.0001, respectively) but not for the TAG device (P = 0.483). In addition, oversize and interactions between variables (angulation × oversize) exhibited significant effects on the DFs for all devices (P < 0.0001).

CONCLUSIONS

We successfully built up an apparatus for comparison of pullout forces for various thoracic stent grafts at varying neck angulations and oversizes. With the empirical comparative data of different brand stent grafts under various conditions shown and compared, our findings suggest that aortic neck angulation has a negative correlation with stent-graft fixation. To have better stent-graft fixation and seal in the aortic arch for thoracic endovascular aortic repair, a longer landing zone with cautiously selected oversize is a more suitable selection.

A computational framework for investigating the positional stability of aortic endografts

Endovascular aneurysm repair (Greenhalgh in N Engl J Med 362(20):1863-1871, 2010) techniques have revolutionized the treatment of thoracic and abdominal aortic aneurysm disease, greatly reducing the perioperative mortality and morbidity associated with open surgical repair techniques. However, EVAR is not free of important complications such as late device migration, endoleak formation and fracture of device components that may result in adverse events such as aneurysm enlargement, need for long-term imaging surveillance and secondary interventions or even death. These complications result from the device inability to withstand the hemodynamics of blood flow and to keep its originally intended post-operative position over time. Understanding the in vivo biomechanical working environment experienced by endografts is a critical factor in improving their long-term performance. To date, no study has investigated the mechanics of contact between device and aorta in a three-dimensional setting. In this work, we developed a comprehensive Computational Solid Mechanics and Computational Fluid Dynamics framework to investigate the mechanics of endograft positional stability. The main building blocks of this framework are: (1) Three-dimensional non-planar aortic and stent-graft geometrical models, (2) Realistic multi-material constitutive laws for aorta, stent, and graft, (3) Physiological values for blood flow and pressure, and (4) Frictional model to describe the contact between the endograft and the aorta. We introduce a new metric for numerical quantification of the positional stability of the endograft. Lastly, in the results section, we test the framework by investigating the impact of several factors that are clinically known to affect endograft stability.

A systematic review of protocols for the three-dimensional morphologic assessment of abdominal aortic aneurysms using computed tomographic angiography

The morphology of infrarenal abdominal aortic aneurysms (AAAs) directly influences the perioperative outcome and long-term durability of endovascular aneurysm repair. A variety of methods have been proposed for the characterization of AAA morphology using reconstructed three-dimensional (3D) computed tomography (CT) images. At present, there is lack of consensus as to which of these methods is most applicable to clinical practice or research. The purpose of this review was to evaluate existing protocols that used 3D CT images in the assessment of various aspects of AAA morphology. An electronic search was performed, from January 1996 to the end of October 2010, using the Embase and Medline databases. The literature review conformed to PRISMA statement standards. The literature search identified 604 articles, of which 31 studies met inclusion criteria. Only 15 of 31 studies objectively assessed reproducibility. Existing published protocols were insufficient to define a single evidence-based methodology for preoperative assessment of AAA morphology. Further development and expert consensus are required to establish a standardized and validated protocol to determine precisely how morphology relates to outcomes after endovascular aneurysm repair.

Composite stent-grafts are not associated with increased endoleak or reintervention rates after endovascular abdominal aneurysm repair

BACKGROUND

Although present-generation endografts have expanded the indications for endovascular abdominal aneurysm repair, arterial anatomy frequently dictates the use of a combination of commercially available endografts and components for successful aneurysm repair. This study sought to determine whether there was an increase in endoleak or secondary intervention rates in individuals treated with composite endografts compared with noncomposite, or standard, endografts.

METHODS

From 1999 to 2009, 421 endovascular abdominal aneurysm repairs were performed at a single institution. A total of 384 patients met criteria for inclusion, with at least one follow-up imaging study. Patients were then identified as having had a composite endograft, defined as any combination of two or more different commercially available endograft or stent components, versus a standard endograft. Primary outcomes measured were freedom from endoleak and secondary intervention.

RESULTS

During the study period, 60 composite endograftings and 324 standard endograftings were performed. The groups were well matched for demographics, including age, gender, comorbidities, emergent need for procedure, and 30-day mortality (1.64% vs. 1.54%, nonsignificant). Median follow-up was 16.3 months (range, 19 days to 8.5 years) and 10.2 months (range, 4 days to 8.7 years) for composite and standard endografts, respectively. There was no significant difference between the groups in either endoleak or secondary intervention rates. Median time to endoleak detection was 2.0 months (range, 2 days to 3.9 years) for composite endografts and 2.8 months (range, 2 days to 6.9 years) for standard endografts. Median time to secondary intervention was 7.0 months (range, 4 days to 6.9 years) for composite endografts and 6.7 months (range, 1 day to 6.7 years) for standard endografts.

CONCLUSIONS

Composite endografts, namely, the combination of different commercially available endografts or stents used for the treatment of aortic aneurysms, are not associated with increased mortality, endoleak, or secondary intervention rates compared with noncomposite endografts.

Experience and outcomes after a decade of endovascular abdominal aortic aneurysm repair: a retrospective study from a community-based single center

BACKGROUND

The purpose of this study is to report the results of endovascular abdominal aortic aneurysm treatment based on the Zenith stent-graft from a community-based single center over a period of 9 years.

METHODS

We retrospectively analyzed immediate technical and clinical results as well as long-term outcomes in patients treated with endovascular aneurysm repair between 2001 and 2010. The study was performed in accordance with the recommendations of the ad hoc committee for standardized reporting practice in vascular surgery.

RESULTS

A total of 106 patients were treated in a period of 9 years. A Zenith stent-graft was used in 95% of cases. No deaths occurred during the first 30 days postsurgery. The complication rate was 4.7% (n = 5). The overall clinical and technical success rate at 30 days was 93.4%. After a mean follow-up period of 52 months (range, 13-112 months), the overall mortality rate was 25.4%. Aneurysm-related mortality was 2.1%. Rupture of the aneurysm occurred in four cases (4.3%). The final clinical failure rate was 13.8%. During the follow-up period, the mean diameter of the aneurysm decreased from 58.0 to 52.3 mm. However, expansion of the aneurysm was registered in 10 cases. Eleven patients had a primary endoleak, and another 11 secondary endoleaks occurred during the follow-up. The reintervention rate was 16.3%. The main reasons for repeat interventions were iliac limb occlusion (n = 5) and type 3 endoleak/limb disconnection (n = 4). Graft migration occurred in 3% of cases. A negative impact on sexual function after endovascular repair was reported by 20% of patients.

CONCLUSION

Endovascular repair is the treatment of choice for high-risk patients. A small but significant number of clinical failures were observed during the long-term follow-up.

The influence of thrombus, calcification, angulation, and tortuosity of attachment sites on the time to the first graft-related complication after endovascular aneurysm repair

PURPOSE

Endovascular aneurysm repair (EVAR) is associated with high graft-related complication rates during follow-up. Anatomical fit between patient and endograft could be an important factor for successful treatment. Aim was to assess whether extent of thrombus, calcification, angulation, and tortuosity are associated with occurrence of complications after EVAR.

MATERIALS AND METHODS

Patients in either United Kingdom EVAR trial 1 or 2 were included if they had undergone EVAR within 6 months of randomization and had a preoperative computed tomography (CT) scan of adequate quality in the core laboratory. Three-dimensional CT imaging was used to assess extent of preoperative thrombus, calcification, angulation, and tortuosity in aneurysm neck and iliac segments. Cox regression modeling, adjusted for the variables tested and for known confounding variables, was used to investigate whether these factors were associated with increased rates of reported first complications.

RESULTS

A total of 217 patients with 53 first graft-related complications were analyzed after a mean follow-up of 3.6 years. Adjusted hazard ratios (95% confidence intervals, P values) for complications per unit increase of variable were 0.96 (0.92-0.99, 0.018) for neck thrombus, 1.06 (1.00-1.12, 0.044) for neck calcification, 1.02 (1.00-1.05, 0.079) for neck angulation, 1.04 (1.01-1.06, 0.011) for common iliac thrombus, 0.96 (0.93-1.00, 0.033) for common iliac calcification, and 5.96 (1.53-23.28, 0.010) for common iliac tortuosity.

CONCLUSION

Increased neck angulation and calcification and common iliac thrombus and tortuosity are associated with higher rates of graft-related complications after EVAR. Increased neck thrombus and common iliac calcification appear to protect against complications. Careful evaluation of these factors prior to EVAR might lead to lower complication rates.

Pulsatility in the iliac artery is significant at several levels: implications for EVAR

PURPOSE

To evaluate the pulsatility of the iliac arteries and compare their distension at several levels that might influence preoperative stent-graft sizing and the long-term durability of stent-graft sealing and fixation.

METHODS

Preoperative dynamic computed tomographic angiography (CTA) scans of 30 patients (24 men; median age 75 years, range 60-85) with an abdominal aortic aneurysm and patent iliac arteries were included. The CTAs consisted of 8 images per heartbeat. Bilateral diameter and area changes per heartbeat were measured semi-automatically in the common iliac artery (CIA) at 3 levels: (A) 0.5 cm after the aortic bifurcation, (B) in the middle of the CIA, and (C) 0.5 cm proximal to the iliac bifurcation. Pulsatility was defined as the largest difference in area and average diameter change over 180 axes per heartbeat. Pulsatility at the 3 levels was compared, and the intraobserver variability of the method was calculated according to Bland and Altman.

RESULTS

The mean area increases in the CIAs at levels A, B, and C were 12.5% (16.3 mm²), 11.2% (13.6 mm²), and 9.6% (12.6 mm²), respectively, and the mean iliac diameter increases were 9.2% (1.1 mm), 8.5% (1.0 mm), and 8.1% (1.0 mm). The iliac distension was statistically significant at all levels. The iliac distension at level A was statistically significantly larger than the distension at level C. The intraobserver variability was 13.3 mm² for area and 0.6 mm for diameter measurements.

CONCLUSION

The pulsatility in the iliac arteries is statistically significant at several levels relevant to endovascular aneurysm repair. The distension of the iliac artery possibly decreases more distally, which might encourage the extension of stent-grafts to the internal iliac artery.