Saccular Abdominal Aortic Aneurysm Research Articles

Saccular and Fusiform Abdominal Aortic Aneurysms Treated With Endovascular Repair Differ in Presentation and Treatment Threshold: Analyses Using a National Clinical Database in Japan.

Saccular abdominal aortic aneurysms (AAAs) are considered to be at higher risk of rupture than fusiform AAAs, but not much is known about the extent of this risk. Therefore, this study aimed to compare the rupture presentation between fusiform and saccular AAAs. This is a retrospective cohort study on 27 290 patients who underwent primary endovascular repair for a degenerative AAA between 2016 and 2019, and who were registered in the National Clinical Database in Japan. At operation for nonruptured case, the aneurysm diameter was significantly smaller in saccular AAAs than in fusiform AAAs (median, 44.0 versus 51.0 mm; P<0.001). Similarly, aneurysm diameter at rupture was significantly smaller in saccular AAAs than in fusiform AAAs (median, 55.6 versus 68.0 mm; P<0.001). The likelihood of repair for rupture was significantly higher in saccular AAAs than in fusiform AAAs in the 40- to 54-mm diameter range, in which saccular morphology was found to be an independent risk factor for rupture against fusiform morphology by adjusting for sex and aneurysm diameter (odds ratio, 2.54 [95% CI, 1.75-3.69]). In addition, receiver-operating characteristic curve analysis revealed that the cutoff diameter to predict rupture was smaller in saccular AAAs than in fusiform AAAs (50.5 and 59.5 mm, respectively) based on the Youden index. Saccular AAAs presented at smaller diameters than fusiform AAAs in patients with ruptured AAAs treated with endovascular aortic repair, which supports the idea that saccular AAAs should be treated at smaller diameters.

Computational Fluid Dynamics Analysis of Blood Flow Changes during the Growth of Saccular Abdominal Aortic Aneurysm.

Computational fluid dynamics analysis of the growth process of saccular abdominal aortic aneurysm was performed. A 3D model of aortic aneurysm was created based on CT images. Properties in terms of wall shear stress, mean flow velocity, mean pressure, energy loss, and pressure loss coefficient were calculated using thermal fluid analysis software "ANSYS CFX." As the aneurysm expanded, the mean flow velocity decreased and the wall shear stress, mean pressure, energy loss, and pressure loss coefficient increased. Wall shear stress increased when the aneurysm was small, suggesting that is related to the development and growth of the aneurysm. (This is secondary publication from J Jpn Coll Angiol 2021; 61: 3-10.).

Midterm outcomes of AFX2 endografts used in combination with aortic cuffs

ObjectiveType III endoleaks after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) with the Endologix unibody endograft remain a major concern, despite fabric, system, and instructional updates. The purpose of this study was to examine real-world outcomes of repairing AAAs using the current version of the AFX2 main body in combination with an aortic cuff, specifically focusing on type III endoleaks and morphological changes of the endograft. MethodsWe recruited facilities in Japan that used AFX2 combined with an aortic cuff for at least five cases between April 2017 and March 2018. A total of 175 cases in 24 facilities were analyzed. Patients’ background information, including anatomic factors, operative findings, device component variations, and midterm outcomes at 3 years after the EVAR were collected. The data on computed tomography scans from cases registered as types I and III endoleaks and migration from each institute were sent to our department for verification. ResultsThe mean patient age was 74.6 ± 8.1 years, and 48 cases (27%) were saccular aneurysms. The mean fusiform and saccular AAA diameters were 50.5 ± 5.8 mm and 43.5 ± 8.9 mm, respectively. No in-hospital deaths occurred. Data at 3 years, including computed tomography images, of 128 cases were analyzed. Overall survival, freedom from aneurysm-related mortality, and freedom from reintervention rates at 3 years were 85.8%, 99.3%, and 87.3%, respectively. There were three, one, and three cases of types I, IIIa, and IIIb endoleaks without sac dilatations, respectively. Among five migration cases, one case of aortic cuff migration presented as a type Ia endoleak, and four cases demonstrated sideways displacement, one of which presented as a type IIIa endoleak. The sac regression and enlargement rates at 3 years were 41.4% and 20.5% in the fusiform group and 44.2% and 16.7% in the saccular group, respectively. The proximal neck diameter slightly increased from 20.8 ± 2.7 mm before the EVAR to 22.2 ± 4.6 mm after the repair. ConclusionsMidterm outcomes of the AFX2 used in combination with an aortic cuff were acceptable, considering the rates of types I and III endoleaks. However, there were cases of sideways displacement that could cause future type IIIa endoleaks. When the AFX2 is used in combination with an aortic cuff, close surveillance for endograft deformations and subsequent adverse events, including type III endoleaks, is needed.

Primary Saccular Abdominal Aortic Aneurysms: Natural History and Contemporary Management

Saccular abdominal aortic aneurysms (sAAAs) are often repaired because of the morphology alone owing to their unknown rupture risk. Limited data are available documenting the natural history of these aneurysms; thus, no consensus has been reached for selective interventions in these patients. In this study, we sought to ascertain the natural history of sAAAs and, thus, define their appropriate management strategy.

Numerical Investigation of Interaction between Saccular Abdominal Aortic Aneurysms and Arterial Bifurcations

In order to fully understand the interaction between the Abdominal Aortic Aneurysms (AAAs) and the arterial bifurcations interface it is important to attain more detailed information on blood hemodynamics stresses by using an accurate and real model of the vascular system of the human. In this study, a computer simulation, which integrates dinically acquired of 73-year-old male patient with saccular AAA MR angiograms image is considered. The numerical predictions for 2D of two models (with and without saccular AAA) – axisymmetric, rigid wall Newtonian and non-Newtonian Carreau blood model are presented. The finite volume method performed by ANSYS-Fluent Package was used to model this problem. The blood hemodynamics is considered as steady state condition in two values of Reynolds numbers of laminar flow condition. Blood hemodynamics is calculated for an improved set of dimensionless values pointer parameters include the pressure dimensionless, dimensionless Wall Shear Stress (WSS) and flow velocity. The results show that at the turbulent flow, velocity is with highest fluctuation profile and generate some vortices near the inner wall of AAA. The highest WSS levels are obtained downstream of AAA and at bifurcation apex. The presence of AAA in flow path will increase blood velocity of the distal by 35% for laminar and about 42% for turbulent. Finally, the velocity profile was compared with previous literature and give good agreement at the same computational condition.

高度貧血を契機に診断されたステントグラフト内挿術後腹部大動脈瘤：十二指腸瘻の1例(Secondary aorto–duodenal fistula following endovascular abdominal aortic aneurysm repair diagnosed by severe anemia)

要旨腹部大動脈ステントグラフト（EVAR）は腹部大動脈瘤（AAA）に対する主な治療として位置づけられ，とくに開腹歴をもつ症例群に対する加療として，低侵襲性の観点で積極的に施行されている。EVAR後に発生するエンドリークは，治療にも関わらず瘤径拡大の主原因であり，周囲臓器との瘻孔や瘤破裂の発生などEVAR関連合併症が発生しうる。EVAR後の大動脈腸管瘻（AEF）の発生は非常に稀であるが，致命的な合併症として知られる。我々は，大腸癌で開腹歴をもつ70歳代女性の拡大傾向のある嚢状AAA対してEVARを施行したが，瘤拡大が持続し十二指腸に穿破した症例を経験した。EVAR術後6か月，16か月後にそれぞれエンドリークによる瘤径拡大に対する追加加療を行ったが，瘤径の制御が困難であった。術後20か月後に高度貧血に対する精査のために施行された上部消化管内視鏡検査の結果，AAAが十二指腸水平脚と交通し出血している所見を認め，AEFの診断となり緊急手術を行った。周術期死亡率の高い本症において，手術侵襲が大きくなることが予想される症例に対して，ステントグラフトを抜去せず瘤縫縮術を選択した1例を報告した。EVAR後の瘤拡大関連イベントに救急医が関わるケースが増えてくることが予想され，AEFの合併を念頭に置くべきである。

Computational Fluid Dynamics Analysis of Blood Flow Changes during the Growth of Saccular Abdominal Aortic Aneurysm

Computational Fluid Dynamics Analysis of Blood Flow Changes during the Growth of Saccular Abdominal Aortic Aneurysm

Saccular Abdominal Aortic Aneurysms: Patient Characteristics, Clinical Presentation, Treatment, and Outcomes in the Netherlands

Observational study of the Dutch Surgical Aneurysm Audit between January 2016 and December 2018. Of 7659 patients with abdominal aortic aneurysms (AAAs), 94% (7188) had fusiform and 6% (471) had saccular AAAs. Significantly more patients with saccular AAAs presented acutely with AAA maximum diameter of less than 5.5 cm (25% vs 8%) and <less than 4.5 cm (8% vs 1%) than did fusiform AAAs. Saccular AAAs present acutely at smaller diameters than fusiform AAAs. Saccular AAAs should be electively treated at smaller diameter (>4.5 cm) than fusiform AAAs (>5.5 cm).

Endovascular aneurysm repair with aorto-uni-iliac device: Review of indications and outcomes with a case report of the deployment in a low-lying dominant accessory renal artery

We present a patient requiring aorto-uni-iliac (AUI) endovascular aneurysm repair with a review of indications and outcomes of this procedure. A 72-year-old male presented at Jain Institute of Vascular Sciences due to infrarenal saccular abdominal aortic aneurysm with a maximum diameter of 4.5 cm. A low-lying, the dominant left accessory renal artery with inadequate length from the origin of the left accessory renal artery to aortic bifurcation (50 mm) precluded the deployment of a bifurcated device (since the length of the aorta from the origin of the left accessory renal artery to aortic bifurcation was inadequate for the contralateral limb to open). Hence, AUI stent-graft deployment, with occlusion of the contralateral common iliac artery and crossover femorofemoral bypass was performed.

Saccular Abdominal Aortic Aneurysms: Patient Characteristics, Clinical Presentation, Treatment, and Outcomes in The Netherlands

Objective:The aim of this was to analyze differences between saccular-shaped abdominal aortic aneurysms (SaAAAs) and fusiform abdominal aortic aneurysms (FuAAAs) regarding patient characteristics, treatment, and outcome, to advise a threshold for intervention for SaAAAs.Background:Based on the assum

Kissing Intravascular Lithotripsy Facilitated Endovascular Repair of a Complex Saccular Abdominal Aortic Aneurysm With Narrowed Distal Aorta: A First-in-Human Report

An 84-year-old woman with known abdominal aortic aneurysm for 18 years, hypertension, chronic obstructive pulmonary disease, obstructive sleep apnea on home oxygen therapy, and carotid artery disease status post–carotid endarterectomy was referred for definitive therapy. Recent computed tomography

Neoaortoiliac system buttressed with tensor fascia lata for treatment of juxtarenal mycotic aortic aneurysm

A 50-year-old man presented with abdominal pain and high-grade fever for 3 months and was diagnosed to have juxtarenal saccular abdominal aortic aneurysm and superior mesenteric artery stenosis on imaging (A). He was diabetic and a chronic smoker. Blood and urine culture specimens had grown group D Salmonella. Open repair of the mycotic aneurysm was done with a neoaortoiliac system using bilateral superficial femoral veins and autologous tensor fascia lata to reinforce the proximal anastomotic line (B and C). The patient was also prescribed long-term antibiotic therapy. The postoperative period was uneventful except for mild lymphorrhea from bilateral thigh wounds that subsided by 1 week. He was discharged on postoperative day 11 with normal pedal pulses and preserved renal function. On 3-month follow-up, the patient is doing well and is asymptomatic. Follow-up computed tomography showed intact anastomoses with good flow through the vein graft (D/Cover). The patient gave informed consent for publication of images and details of the case. Femoropopliteal vein conduit to reconstruct the aortoiliac vasculature has excellent long-term durability and is resistant to infection, which makes it a useful treatment option in cases of mycotic aneurysm.1Bernatchez J. Gauvin V. Gilbert N. Rhéaume P. Long-term results of the neoaortoiliac system procedure for aortic graft infections and mycotic aneurysms: a single-center experience.J Vasc Surg. 2016; 64: 1544Abstract Full Text Full Text PDF Google Scholar Autologous tensor fascia lata was used to buttress the proximal anastomotic line as the posterior aortic wall at the anastomosis was diseased; it will also minimize the risk of infection compared with synthetic felt pledget. Salmonella is associated with persistent and extended infection, and the virulence of the organism involved is to be considered in planning endovascular aneurysm repair. Endovascular management with fenestrated endovascular aneurysm repair should be considered only in select critically ill patients with complex mycotic aneurysms in whom surgical management is too risky, considering the high risk of persistent infection and associated complications after the procedure.2Sörelius K. Mani K. Björck M. Nyman R. Wanhainen A. Endovascular repair of mycotic aortic aneurysms.J Vasc Surg. 2009; 50: 269-274Abstract Full Text Full Text PDF PubMed Scopus (69) Google Scholar Because our patient was young and otherwise healthy, we opted for open repair of the aneurysm. Limiting the extent of femoral vein harvest to the adductor canal, as in this case, will help in reducing the risk for development of compartment syndrome in the postoperative period as it will preserve the profunda vein and popliteal genicular draining veins.

Open repair of an abdominal aortic aneurysm in a patient with congenital renal vascular anomalies

Purpose: The renal vasculature is unique in such a way that each artery behaves as an end artery. The amount of renal damage that can occur by sacrificing these arteries are so unpredictable. The presence of aberrant or accessory renal arteries makes open repair of the abdominal aortic aneurysm (AAA) technically more challenging than conventional surgery. Here, we describe various techniques used to preserve the renal vasculature and prevent renal ischemia during surgery. Methods: We present a case of saccular AAA with low lying right kidney with an aberrant renal artery arising from neck and an accessory renal artery arising from the body of the aneurysm. We performed an open repair of the aneurysm, during which we did inter-renal clamping and renal perfusion with renoplegia solution using Pruitt-Inahara shunt. Conclusions: Interrenal clamping and administration of optimal renoplegia solution through shunt are very useful adjuncts to prevent renal ischemia during open repair of AAA with congenital renal vascular anomalies. Pruitt-Inahara Shunt, classically described in carotid endarterectomy, can be used in AAA surgeries for administering renoplegia.

Midterm Analysis of Survival and Cause of Death Following Endovascular Abdominal Aortic Aneurysm Repair.

To assess rates of complications, secondary interventions, survival, and cause of death following endovascular abdominal aortic aneurysm (AAA) repair over a 10-year period. Single-institution retrospective cohort study of all patients undergoing primary endovascular aortic aneurysm repair (EVAR) between July 2006 and June 2015. The population constituted 175 patients with 163 fusiform and 12 saccular AAAs. Of these, 149 (85%) were male, with mean age 75.4 (±7.1) years. Patients were followed up until June 30, 2016. Cause of death was determined from the national death register. Mean follow-up was 34.4 (±24.4) months. The secondary intervention rate was 9.7%, and there were 4 aneurysm ruptures (0.8% annual incidence). Thirty-day mortality was 0.6%. Survival at 1, 3, and 5 years was 93.1%, 84%, and 64.9%, respectively. Forty-eight patients died during follow-up, 3 secondary to rupture, leading to overall and aneurysm-related death rates of 9.7 and 0.6 per 100 person-years. All other deaths were due to nonaneurysm causes, most commonly cardiovascular (n = 15), pulmonary (n = 13), and malignancy (n = 9). Baseline renal impairment ( P < .001), ischemic heart disease ( P < .05), age greater than 75 years ( P < .05), and urgent/emergency EVAR were associated with inferior long-term survival. Type II endoleak negatively influenced fusiform aneurysm sac regression ( P = .02), but there was no association between survival and occurrence of any complication or secondary intervention. The majority of deaths during medium-term follow-up post-EVAR are due to nonaneurysm-related causes. Survival is determined by the following baseline factors: renal impairment, ischemic heart disease, advanced age, and the presence of a symptomatic/ruptured aneurysm.

Use of Endurant Stent-Graft Aortic Extensions for the Treatment of Focal Aortic Pathology

To describe our experience with the endovascular treatment of focal abdominal aortic pathology with an adequate distal neck length using Endurant (Medtronic) aortic extension cuffs. From July 2010 to May 2015, 16 patients (14 male), with a mean age of 73.6years (range, 59-88), were treated for focal abdominal aortic pathology using only Endurant (Medtronic) aortic cuff extensions. The indication for intervention was a saccular abdominal aortic aneurysm (AAA) in 5 patients, a fusiform aortic aneurysm in 6 patients, abdominal aortic dissection in 2 patients, an aortic juxtarenal rupture in 1 patient, a large anastomotic pseudoaneurysm of previous bifurcated open repair in 1 patient, and a juxtarenal aneurysm above a previous open AAA repair. Aortic lesions had a mean diameter of 52.9 (range, 32-90) mm. All patients were operated under local anesthesia with unilateral femoral exposure. A single 70-mm long Endurant aortic extension was deployed in 5 cases, while in the remaining 11 cases, 2 cuffs were used with the "telescopic" (double tube) technique. A chimney technique was performed in 5 cases (with a bare metal stent in the renal artery in 3 and a stent graft in the celiac artery in 2). The intraoperative technical success was 100% with no endoleaks on completion angiogram. There was no 30-day mortality. One patient developed acute limb ischemia immediately postoperatively and was treated successfully with thrombectomy. During a mean follow-up of 21.9months, 1 patient died 2months after the procedure due to cardiac arrest unrelated to his aortic operation. There was 1 early type IIb endoleak (present at the 30-day follow-up computerized tomography scan), which disappeared 10months after the procedure. Finally, 1 patient was diagnosed with a type II endoleak and stable diameter 53months postoperatively, while to date there are no cases of stent-graft migration. The use of Endurant aortic extensions in aneurysms with adequate distal neck is a safe, simple, customizable, and cost-effective method which presents similar early results with standard endovascular aneurysm repair technique.

Alterations of blood flow pattern after triple stent endovascular treatment of saccular abdominal aortic aneurysm: a porcine model.

to determine the blood flow pattern changes after endovascular treatment of saccular abdominal aortic aneurysm with triple stent. we conducted a hemodynamic study of seven Landrace and Large White pigs with saccular aneurysms of the infrarenal abdominal aorta artificially produced according to the technique described. The animals were subjected to triple stenting for endovascular aneurysm. We evaluated the pattern of blood flow by duplex scan before and after stent implantation. We used the non-paired Mann-Whitney test for statistical analysis. there was a significant decrease in the average systolic velocity, from 127.4cm/s in the pre-stent period to 69.81cm/s in the post-stent phase. There was also change in the flow pattern from turbulent in the aneurysmal sac to laminate intra-stent. there were changes in the blood flow pattern of saccular abdominal aortic aneurysm after endovascular treatment with triple stent. determinar as alterações do padrão do fluxo sanguíneo após tratamento endovascular do aneurisma sacular de aorta abdominal com triplo stent. estudo hemodinâmico de sete suínos das raças Landrace e Large White portadores de aneurismas saculares de aorta abdominal infrarrenal artificialmente produzidos segundo técnica descrita. Os animais foram submetidos a implante de triplo stent para correção endovascular do aneurisma e reavaliados por duplex scan quanto ao padrão do fluxo sanguíneo antes e após o implante dos stents. A análise estatística foi realizada com o teste Mann-Whitney não pareado. verificou-se uma queda significativa da velocidade sistólica média de 127,4cm/s na fase pré-stent para 69,81cm/s na fase pós-stent. Houve ainda mudança no padrão do fluxo de turbilhonar no saco aneurismático para laminar intrastent. o estudo demonstrou alterações do padrão do fluxo sanguíneo do aneurisma sacular de aorta abdominal após tratamento endovascular com triplo stent.

Combined Transcatheter Aortic Valve Replacement and Endovascular Aortic Repair: A Transfemoral Approach Dilemma

We report a case of an elderly patient with severe aortic stenosis (AS) too risky for conventional surgery because of comorbidities that included an infrarenal saccular abdominal aortic aneurysm (AAA). The presence of the aneurysm could impact the outcome of transcatheter aortic valve replacement (TAVR) as improved systolic pressure could increase the risk of aneurysm rupture. Transapical and transaortic approaches for TAVR precluded simultaneous endovascular aortic repair (EVAR). Transfemoral approach was the most viable option. Doing EVAR first would circumvent aortic rupture but it could be technically precarious to do EVAR before TAVR when both are done transfemorally. Contrast-induced nephropathy could be considered whether combined procedure is riskier than angiogram-dependent procedures performed in two settings. The patient underwent uncomplicated transfemoral TAVR and then EVAR in one setting. This case underscores the management strategy of a patient with this complicated clinical presentation and underlying pathologies in the light of presently available technologies.

Emergency endovascular management of leaking saccular abdominal aortic aneurysm

Emergency endovascular management of leaking saccular abdominal aortic aneurysm

Morphology of Small Abdominal Aortic Aneurysms Should be Considered before Continued Ultrasound Surveillance

To evaluate abdominal aortic aneurysm (AAA) morphology in a cohort of patients presenting with ruptured AAA (rAAA) and to explore if aneurysms with diameters below the recommended threshold for elective repair (<55mm) have some distinctive morphological characteristics. All patients diagnosed with rAAA using computed tomography (CT) scans between January 2006 and June 2013 were eligible for this study. Where CT scans of acceptable quality were available, images were reconstructed in a dedicated three-dimensional vascular workstation for evaluation of aneurysm diameters and morphology. All morphological characteristics were defined according to the reporting standards for endovascular aortic aneurysm repair. Additionally, fusiform AAAs were defined as aneurysms involving the whole circumference of the aortic wall and saccular AAAs as spherical aneurysms involving only a portion of the aortic circumference. A total of 248 patients were identified. Of those, 83% (n=206) had high-quality CT scans available and were included in the study. Patients were on average 75years old and 85% were men. Mean aneurysm diameter was 76±14mm and 95% (n=197) had fusiform morphology. Six percent (n = 12) were <55 mm and those included all saccular aneurysms in women (n = 3) and 22% of saccular aneurysms in men (n = 2). The remaining saccular aneurysms (n=4) were small with a maximal diameter of 56mm. Aneurysms <55mm had less angulated proximal necks than their larger counterparts (P<0.01). No other morphological differences were found between the groups. Ruptured aneurysms are often large and the ≥55mm threshold for elective repair is probably appropriate. However, approximately 6% of rAAAs are <55mm, with a significant portion being saccular, especially in women. Morphological assessment of AAAs with CT scans should be considered in small aneurysms (40-55mm), particularly in women, to exclude saccular morphology before continued ultrasound surveillance.

Emergency endovascular management of a leaking saccular abdominal aortic aneurysm

Abdominal aortic aneurysms (AAA) are relatively common, potentially life threatening conditions that are often asymptomatic and incidentally detected on routine screening for other problems. Vague abdominal pain and back ache are often the presenting complaints of this disease and are also the commonest complaints that a doctor comes across in the outpatient as well as the emergency room (ER). Hence it is easy to misdiagnose an AAA. A case report illustrating one such patient who presented to the gastroenterologist with vague abdominal pain and backache in whom an abdominal aneurysm was incidentally detected on ultrasound, is presented here. The patient course and complications that developed along with key points to be learnt so as to identify this disease at an early stage and prevent its complications, are discussed. Keywords: abdominal aortic aneurysm; EVAR; ultrasound screening for aneurysm; saccular aneurysm