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Sample records for abdominal aortic constriction

  1. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis or plaque buildup causes the ... weak and bulge outward like a balloon. An AAA develops slowly over time and has few noticeable ...

  2. Abdominal aortic aneurysm

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000162.htm Abdominal aortic aneurysm To use the sharing features on this page, ... blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ...

  3. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Ziaja, K; Sedlak, L; Urbanek, T; Kostyra, J; Ludyga, T

    2000-01-01

    The reported incidence of inflammatory abdominal aortic aneurysm (IAAA) is from 2% to 14% of patients with abdominal aortic aneurysm and the etiology of this disease is still discussed--according to the literature several pathogenic theories have been proposed. From 1992 to 1997 32 patients with IAAA were operated on. The patients were mostly symptomatic--abdominal pain was present in 68.75% cases, back pain in 31.25%, fever in 12.5% and weight loss in 6.25% of the operated patients. In all the patients ultrasound examination was performed, in 4 patients CT and in 3 cases urography. All the patients were operated on and characteristic signs of inflammatory abdominal aortic aneurysm like: thickened aortic wall, perianeurysmal infiltration or retroperitoneal fibrosis with involvement of retroperitoneal structures were found. In all cases surgery was performed using transperitoneal approach; in three cases intraoperatively contiguous abdominal organs were injured, which was connected with their involvement into periaortic inflammation. In 4 cases clamping of the aorta was done at the level of the diaphragmatic hiatus. 3 patients (9.37%) died (one patient with ruptured abdominal aortic aneurysm). Authors present diagnostic procedures and the differences in the surgical tactic, emphasizing the necessity of the surgical therapy in patients with inflammatory abdominal aortic aneurysm.

  4. Inflammatory abdominal aortic aneurysm.

    PubMed

    Savarese, R P; Rosenfeld, J C; DeLaurentis, D A

    1986-05-01

    Between January 1976 and December 1982, 181 patients with abdominal aortic aneurysms were treated surgically, and in 13 patients the aneurysms were found to be inflammatory. Inflammatory aneurysms of the abdominal aorta (IAAA) share important characteristics with typical atherosclerotic abdominal aortic aneurysms. Diagnosis and surgical management of IAAA are distinctive which suggests that IAAA should be considered separately, as a varient of typical abdominal aortic aneurysms. IAAA occur predominantly in males. The presenting symptoms are often idiosyncratic and include severe abdominal or back pain, or both, and ureteral obstruction; the diagnosis of IAAA should be considered when these symptoms are present. Although grossly and microscopically, the perianeurysmal fibrosis resembles idiopathic retroperitoneal fibrosis, the two conditions can be differentiated. At the present time, ultrasonography and computed tomography appear to offer reliable means for diagnosing IAAA. The presence of IAAA, whether established preoperatively or discovered unexpectedly at operation, necessitate certain modifications in the surgical approach, in order to avoid injuring the duodenum and the venous structures. Most patients can be successfully treated by resection and graft replacement. Rupture of the aneurysm in IAAA appears to be less frequent than in typical atherosclerotic abdominal aortic aneurysm.

  5. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Mikami, Y; Kyogoku, M

    1994-08-01

    Inflammatory abdominal aortic aneurysm (IAAA) is a distinct clinicopathological entity, characterized by: (1) clinical presentation, such as back pain, weight loss, and increased ESR, (2) patchy and/or diffuse lymphoplasmacytic infiltration, and (3) marked periaortic fibrosis resulting in thickening of the aneurysmal wall and occasional retroperitoneal fibrosis. Its pathogenesis is unknown, but some authors support the theory that IAAA is a subtype of atherosclerotic abdominal aortic aneurysm because of close relationship between IAAA and atherosclerotic change. In this article, we describe clinical and histological features of IAAA on the basis of the literature and our review of 6 cases of IAAA, emphasizing the similarity and difference between IAAA and atherosclerotic abdominal aortic aneurysm. Our review supports that marked lamellar fibrosis completely replacing the media and adventitia, patchy lymphocytic infiltration (mostly B cells) and endarteritis obliterans are characteristic features of IAAA.

  6. Ruptured abdominal aortic aneurysm.

    PubMed

    Sachs, T; Schermerhorn, M

    2010-06-01

    Ruptured abdominal aortic aneurysm (AAA) continues to be one of the most lethal vascular pathologies we encounter. Its management demands prompt and efficient evaluation and repair. Open repair has traditionally been the mainstay of treatment. However, the introduction of endovascular techniques has altered the treatment algorithm for ruptured AAA in most major medical centers. We present recent literature and techniques for ruptured AAA and its surgical management.

  7. Myeloid mineralocorticoid receptor deficiency inhibits aortic constriction-induced cardiac hypertrophy in mice.

    PubMed

    Li, Chao; Zhang, Yu Yao; Frieler, Ryan A; Zheng, Xiao Jun; Zhang, Wu Chang; Sun, Xue Nan; Yang, Qing Zhen; Ma, Shu Min; Huang, Baozhuan; Berger, Stefan; Wang, Wang; Wu, Yong; Yu, Ying; Duan, Sheng Zhong; Mortensen, Richard M

    2014-01-01

    Mineralocorticoid receptor (MR) blockade has been shown to suppress cardiac hypertrophy and remodeling in animal models of pressure overload (POL). This study aims to determine whether MR deficiency in myeloid cells modulates aortic constriction-induced cardiovascular injuries. Myeloid MR knockout (MMRKO) mice and littermate control mice were subjected to abdominal aortic constriction (AAC) or sham operation. We found that AAC-induced cardiac hypertrophy and fibrosis were significantly attenuated in MMRKO mice. Expression of genes important in generating reactive oxygen species was decreased in MMRKO mice, while that of manganese superoxide dismutase increased. Furthermore, expression of genes important in cardiac metabolism was increased in MMRKO hearts. Macrophage infiltration in the heart was inhibited and expression of inflammatory genes was decreased in MMRKO mice. In addition, aortic fibrosis and inflammation were attenuated in MMRKO mice. Taken together, our data indicated that MR deficiency in myeloid cells effectively attenuated aortic constriction-induced cardiac hypertrophy and fibrosis, as well as aortic fibrosis and inflammation.

  8. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Siebenmann, R; Schneider, K; von Segesser, L; Turina, M

    1988-06-11

    348 cases of abdominal aortic aneurysm were reviewed for typical features of inflammatory aneurysm (IAAA) (marked thickening of aneurysm wall, retroperitoneal fibrosis and rigid adherence of adjacent structures). IAAA was present in 15 cases (14 male, 1 female). When compared with patients who had ordinary aneurysms, significantly more patients complained of back or abdominal pain (p less than 0.01). Erythrocyte sedimentation rate was highly elevated. Diagnosis was established in 7 of 10 computed tomographies. 2 patients underwent emergency repair for ruptured aneurysm. Unilateral ureteral obstruction was present in 4 cases and bilateral in 1. Repair of IAAA was performed by a modified technique. Histological examination revealed thickening of the aortic wall, mainly of the adventitial layer, infiltrated by plasma cells and lymphocytes. One 71-year-old patient operated on for rupture of IAAA died early, and another 78-year-old patient after 5 1/2 months. Control computed tomographies revealed spontaneous regression of inflammatory infiltration after repair. Equally, hydronephrosis due to ureteral obstruction could be shown to disappear or at least to decrease. IAAA can be diagnosed by computed tomography with high sensitivity. Repair involves low risk, but modification of technique is necessary. The etiology of IAAA remains unclear.

  9. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    ... signs or symptoms of an abdominal aortic aneurysm (AAA). The final recommendation statement summarizes what the Task ... the potential benefits and harms of screening for AAA: (1) Men ages 65 to 75 who smoke ...

  10. Abdominal aortic feminism.

    PubMed

    Mortimer, Alice Emily

    2014-11-14

    A 79-year-old woman presented to a private medical practice 2 years previously for an elective ultrasound screening scan. This imaging provided the evidence for a diagnosis of an abdominal aortic aneurysm (AAA) to be made. Despite having a number of recognised risk factors for an AAA, her general practitioner at the time did not follow the guidance set out by the private medical professional, that is, to refer the patient to a vascular specialist to be entered into a surveillance programme and surgically evaluated. The patient became symptomatic with her AAA, was admitted to hospital and found to have a tender, symptomatic, 6 cm leaking AAA. She consented for an emergency open AAA repair within a few hours of being admitted to hospital, despite the 50% perioperative mortality risk. The patient spent 4 days in intensive care where she recovered well. She was discharged after a 12 day hospital stay but unfortunately passed away shortly after her discharge from a previously undiagnosed gastric cancer.

  11. Abdominal aortic aneurysms in women

    PubMed Central

    Lo, Ruby C.; Schermerhorn, Marc L.

    2015-01-01

    Abdominal aortic aneurysm (AAA) has long been recognized as a condition predominantly afflicting males, with sex-associated differences described for almost every aspect of the disease from pathophysiology and epidemiology to morbidity and mortality. Women are generally spared from AAA formation by the immunomodulating effects of estrogen but once they develop, the natural history of AAAs in women appears to be more aggressive, with more rapid expansion, a higher tendency to rupture at smaller diameters, and higher mortality following rupture. However, simply repairing AAA at smaller diameters in women is a debatable solution, as even elective endovascular AAA repair (EVAR) is fraught with higher morbidity and mortality in women compared to men. The goal of this review is to summarize what is currently known about the effect of gender on AAA presentation, treatment, and outcomes. Additionally, we aim to review current controversies over screening recommendations and threshold for repair in women. PMID:26747679

  12. Successful transfemoral aortic valve implantation through aortic stent graft after endovascular repair of abdominal aortic aneurysm.

    PubMed

    Kawashima, Hideyuki; Watanabe, Yusuke; Kozuma, Ken

    2017-04-01

    The patient was a 91-year-old woman presenting with severe aortic valve stenosis. Pre-procedural computed tomography scan revealed a 45-mm abdominal aortic aneurysm (AAA). Transfemoral transcatheter aortic valve implantation (TF-TAVI) was performed after endovascular aortic repair (EVAR) of the AAA. The 23-mm Edwards Sapien XT system passed through the aortic stent graft smoothly. This is the first case report showing that successful TF-TAVI can be performed through a prior abdominal aortic stent graft. TF-TAVI after EVAR of AAA is a feasible option for patients with extremely poor access.

  13. Aortic Remodeling Following Transverse Aortic Constriction in Mice is Attenuated with AT1 Receptor Blockade

    PubMed Central

    Kuang, Shao-Qing; Geng, Liang; Prakash, Siddharth K.; Cao, Jiu-Mei; Guo, Steven; Villamizar, Carlos; Kwartler, Callie S.; Ju, Xiaoxi; Brasier, Allan R.; Milewicz, Dianna M.

    2016-01-01

    Objective Although hypertension is the most common risk factor for thoracic aortic diseases, it is not understood how increased pressures on the ascending aorta lead to aortic aneurysms. We investigated the role of Ang II type 1 (AT1) receptor activation in ascending aortic remodeling in response to increased biomechanical forces using a transverse aortic constriction (TAC) mouse model. Approach and Results Two weeks after TAC, the increased biomechanical pressures led to ascending aortic dilatation, aortic wall thickening and medial hypertrophy. Significant adventitial hyperplasia and inflammatory responses in TAC ascending aortas were accompanied by increased adventitial collagen, elevated inflammatory and proliferative markers, and increased cell density due to accumulation of myofibroblasts and macrophages. Treatment with losartan significantly blocked TAC induced vascular inflammation and macrophage accumulation. However, losartan only partially prevented TAC induced adventitial hyperplasia, collagen accumulation and ascending aortic dilatation. Increased Tgfb2 expression and phosphorylated-Smad2 staining in the medial layer of TAC ascending aortas was effectively blocked with losartan. In contrast, the increased Tgfb1 expression and adventitial phospho-Smad2 staining were only partially attenuated by losartan. In addition, losartan significantly blocked Erk activation and ROS production in the TAC ascending aorta. Conclusions Inhibition of the AT1 receptor using losartan significantly attenuated the vascular remodeling associated with TAC but did not completely block the increased TGF- β1 expression, adventitial Smad2 signaling and collagen accumulation. These results help to delineate the aortic TGF-β signaling that is dependent and independent of the AT1 receptor after TAC. PMID:23868934

  14. Talk to Your Doctor about Abdominal Aortic Aneurysm

    MedlinePlus

    ... español Talk to Your Doctor about Abdominal Aortic Aneurysm Browse Sections The Basics Overview What is AAA? ... doctor about getting screened (tested) for abdominal aortic aneurysm (AAA). If AAA isn't found and treated ...

  15. Quantification of abdominal aortic deformation after EVAR

    NASA Astrophysics Data System (ADS)

    Demirci, Stefanie; Manstad-Hulaas, Frode; Navab, Nassir

    2009-02-01

    Quantification of abdominal aortic deformation is an important requirement for the evaluation of endovascular stenting procedures and the further refinement of stent graft design. During endovascular aortic repair (EVAR) treatment, the aortic shape is subject to severe deformation that is imposed by medical instruments such as guide wires, catheters, and, the stent graft. This deformation can affect the flow characteristics and morphology of the aorta which have been shown to be elicitors for stent graft failures and be reason for reappearance of aneurysms. We present a method for quantifying the deformation of an aneurysmatic aorta imposed by an inserted stent graft device. The outline of the procedure includes initial rigid alignment of the two abdominal scans, segmentation of abdominal vessel trees, and automatic reduction of their centerline structures to one specified region of interest around the aorta. This is accomplished by preprocessing and remodeling of the pre- and postoperative aortic shapes before performing a non-rigid registration. We further narrow the resulting displacement fields to only include local non-rigid deformation and therefore, eliminate all remaining global rigid transformations. Finally, deformations for specified locations can be calculated from the resulting displacement fields. In order to evaluate our method, experiments for the extraction of aortic deformation fields are conducted on 15 patient datasets from endovascular aortic repair (EVAR) treatment. A visual assessment of the registration results and evaluation of the usage of deformation quantification were performed by two vascular surgeons and one interventional radiologist who are all experts in EVAR procedures.

  16. [Albert Einstein and his abdominal aortic aneurysm].

    PubMed

    Cervantes Castro, Jorge

    2011-01-01

    The interesting case of Albert Einstein's abdominal aortic aneurysm is presented. He was operated on at age 69 and, finding that the large aneurysm could not be removed, the surgeon elected to wrap it with cellophane to prevent its growth. However, seven years later the aneurysm ruptured and caused the death of the famous scientist.

  17. Understanding the pathogenesis of abdominal aortic aneurysms

    PubMed Central

    Kuivaniemi, Helena; Ryer, Evan J.; Elmore, James R.; Tromp, Gerard

    2016-01-01

    Summary An aortic aneurysm is a dilatation in which the aortic diameter is ≥ 3.0 cm. If left untreated, the aortic wall continues to weaken and becomes unable to withstand the forces of the luminal blood pressure resulting in progressive dilatation and rupture, a catastrophic event associated with a mortality of 50 – 80%. Smoking and positive family history are important risk factors for the development of abdominal aortic aneurysms (AAA). Several genetic risk factors have also been identified. On the histological level, visible hallmarks of AAA pathogenesis include inflammation, smooth muscle cell apoptosis, extracellular matrix degradation, and oxidative stress. We expect that large genetic, genomic, epigenetic, proteomic and metabolomic studies will be undertaken by international consortia to identify additional risk factors and biomarkers, and to enhance our understanding of the pathobiology of AAA. Collaboration between different research groups will be important in overcoming the challenges to develop pharmacological treatments for AAA. PMID:26308600

  18. Abdominal Aortic Surgery: Anesthetic Implications

    PubMed Central

    Cunningham, Anthony J.

    1991-01-01

    The objectives of the review are to highlight the clinical characteristics of the patient population; to assess multivariate risk factor analysis and the invasive/non-invasive techniques available for risk factor identification and management in this high-risk surgical population; to assess the major hemodynamic, metabolic, and regional blood flow changes associated with aortic cross-clamping/unclamping procedures and techniques for their modification or attenuation; and to assess the influence of perioperative anesthetic techniques and management on patient outcome. PMID:1814052

  19. Gender Differences in Abdominal Aortic Aneurysms

    PubMed Central

    Hannawa, Kevin K.; Eliason, Jonathan L.; Upchurch, Gilbert R.

    2010-01-01

    Abdominal aortic aneurysms (AAAs) comprise the 10th leading cause of death in Caucasian males 65–74 years of age, and accounted for nearly 16,000 deaths overall in the year 2000. Therefore, understanding the pathophysiology of AAAs is an important undertaking. Clinically, multiple risk factors are associated with the development of AAAs, including increasing age, positive smoking history, and hypertension. Male gender is also a well-established risk factor for the development of an AAA with a 4:1 male to female ratio. The reason for this gender disparity is unknown. The pathogenesis of AAAs formation is complex and multifactorial. Histologically, AAAs are characterized by early chemokine driven leukocyte infiltration into the aortic wall. Subsequent destruction of elastin and collagen in the media and adventitia ensues due to excessive local production of matrix degrading enzymes, and is accompanied by smooth muscle cell loss and thinning of the aortic wall. At present, there are no medical therapies available to treat patients with aortic aneurysms, using only the crude measurement of aortic diameter as a threshold for which patients must undergo life-threatening and costly surgery. Defining the early mechanisms underlying gender-related differences in AAA formation are critical, as understanding differences in disease patterns based on gender may allow us to develop new translational approaches to the prevention and treatment of patients with aortic aneurysms. PMID:19426607

  20. Abdominal aortic aneurysm: A comprehensive review

    PubMed Central

    Aggarwal, Sourabh; Qamar, Arman; Sharma, Vishal; Sharma, Alka

    2011-01-01

    An arterial aneurysm is defined as a focal dilation of a blood vessel with respect to the original artery. The risk of abdominal aortic aneurysms (AAAs) increases dramatically in the presence of the following factors: age older than 60 years, smoking, hypertension and Caucasian ethnicity. The likelihood that an aneurysm will rupture is influenced by the aneurysm size, expansion rate, continued smoking and persistent hypertension. The majority of AAAs are asymptomatic and are detected as an incidental finding on ultrasonography, abdominal computed tomography or magnetic resonance imaging performed for other purposes. It can also present with abdominal pain or complications such as thrombosis, embolization and rupture. Approximately 30% of asymptomatic AAAs are discovered as a pulsatile abdominal mass on routine physical examination. Abdominal ultrasonography is considered the screening modality of choice for detecting AAAs because of its high sensitivity and specificity, as well as its safety and relatively lower cost. The decision to screen for AAAs is challenging. The United States Preventive Services Task Force recommended that men between the age of 65 to 75 years who have ever smoked should be screened at least once for AAAs by abdominal ultrasonography. Management options for patients with an asymptomatic AAA include reduction of risk factors such as smoking, hypertension and dyslipidemia; medical therapy with beta-blockers; watchful waiting; endovascular stenting; and surgical repair depending on the size and expansion rate of the aneurysm and underlying comorbidities. PMID:21523201

  1. Surrogate Markers of Abdominal Aortic Aneurysm Progression.

    PubMed

    Wanhainen, Anders; Mani, Kevin; Golledge, Jonathan

    2016-02-01

    The natural course of many abdominal aortic aneurysms (AAA) is to gradually expand and eventually rupture and monitoring the disease progression is essential to their management. In this publication, we review surrogate markers of AAA progression. AAA diameter remains the most widely used and important marker of AAA growth. Standardized reporting of reproducible methods of measuring AAA diameter is essential. Newer imaging assessments, such as volume measurements, biomechanical analyses, and functional and molecular imaging, as well as circulating biomarkers, have potential to add important information about AAA progression. Currently, however, there is insufficient evidence to recommend their routine use in clinical practice.

  2. Endovascular Repair of a Blunt Abdominal Aortic Injury

    PubMed Central

    Tobler, William D.; Tan, Tze-Woei; Farber, Alik

    2012-01-01

    Blunt abdominal aortic injury is an uncommon traumatic finding. In the past, treatment options have traditionally consisted of open operative repair; however, the development of endovascular surgery has created new interventional possibilities. This case is presented to demonstrate the applications of endovascular abdominal aortic repair for a blunt traumatic injury. PMID:23730142

  3. Monocytes and macrophages in abdominal aortic aneurysm.

    PubMed

    Raffort, Juliette; Lareyre, Fabien; Clément, Marc; Hassen-Khodja, Réda; Chinetti, Giulia; Mallat, Ziad

    2017-04-13

    Abdominal aortic aneurysm (AAA) is a life-threatening disease associated with high morbidity, and high mortality in the event of aortic rupture. Major advances in open surgical and endovascular repair of AAA have been achieved during the past 2 decades. However, drug-based therapies are still lacking, highlighting a real need for better understanding of the molecular and cellular mechanisms involved in AAA formation and progression. The main pathological features of AAA include extracellular matrix remodelling associated with degeneration and loss of vascular smooth muscle cells and accumulation and activation of inflammatory cells. The inflammatory process has a crucial role in AAA and substantially influences many determinants of aortic wall remodelling. In this Review, we focus specifically on the involvement of monocytes and macrophages, summarizing current knowledge on the roles, origin, and functions of these cells in AAA development and its complications. Furthermore, we show and propose that distinct monocyte and macrophage subsets have critical and differential roles in initiation, progression, and healing of the aneurysmal process. On the basis of experimental and clinical studies, we review potential translational applications to detect, assess, and image macrophage subsets in AAA, and discuss the relevance of these applications for clinical practice.

  4. Volumetric analysis of abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Baskin, Kevin M.; Kusnick, Catherine A.; Shamsolkottabi, Susanne; Lang, Elvira V.; Corson, J. D.; Stanford, William; Thompson, Brad H.; Hoffman, Eric A.

    1996-04-01

    The purpose of this study was to develop a valid, reliable and accurate system of measurement of abdominal aortic aneurysms, using volumetric analysis of x-ray computed tomographic data. This study evaluates illustrative cases, and compares measurements of AAA phantoms, using standard 2D versus volumetric methods. To validate the volumetric analysis, four phantom aneurysms were constructed in a range of diameters (4.5 - 7.0 cm) which presents the greatest management challenge to the clinician. These phantoms were imaged using a Toshiba Xpress SX helical CT. Separate scans were obtained at conventional (10 mm X 10 mm) and thin slice (5 mm X 5 mm) collimations. The thin slices were reconstructed at 2 mm intervals. Data from each of the 96 scans were interpreted using a standard 2D approach, then analyzed using task-oriented volumetric software. We evaluate patient assessments, and compare greatest outer diameters of phantoms, by standard versus volumetric methods. Qualitative differences between solutions based on standard versus volumetric analysis of illustrative patient cases are substantial. Expert radiologists' standard measurements of phantom aneurysms are highly reliable (r2 equals 0.901 - 0.958; p < 0.001), but biased toward significant overestimation of aneurysm diameters in the range of clinical interest. For the same phantoms, volumetric analysis was both more reliable (r2 equals 0.986 - 0.996; p < 0.001), and more accurate, with no significant bias in the range of interest. Volumetric analysis promotes selection of more valid management strategies, by providing vital information not otherwise available, and allowing more reliable and accurate assessment of abdominal aortic aneurysms. It is particularly valuable in the presence of aortic tortuosity, vessel eccentricity, and uncertain involvement of critical vessels.

  5. Flexible tubular replicas of abdominal aortic aneurysms.

    PubMed

    Berry, E; Marsden, A; Dalgarno, K W; Kessel, D; Scott, D J A

    2002-01-01

    The aim of this study was to manufacture life-size, flexible, tubular replicas of human abdominal aortic aneurysms and the associated vasculature, suitable for use in a training simulator for endovascular procedures. Selective laser sintering was used to create a geometrically correct master model for each of ten anatomical variations. The masters were used to generate flexible latex replicas. The use of the replicas in the training simulator was demonstrated. In total ten silicone rubber models were produced. When connected into the training simulator and perfused at arterial pressure it was possible to deploy an endovascular stent under fluoroscopic control and to perform angiography. The study has shown that conventional rapid prototyping technology can be used to manufacture flexible, radiolucent replicas which provide a realistic training environment for endovascular procedures.

  6. Pulsatile blood flow in Abdominal Aortic Aneurysms

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Lasheras, Juan C.; Singel, Soeren; Varga, Chris

    2001-11-01

    We discuss the results of combined in-vitro laboratory measurements and clinical observations aimed at determining the effect that the unsteady wall shear stresses and the pressure may have on the growth and eventual rupturing of an Abdominal Aortic Aneurysm (AAA), a permanent bulging-like dilatation occurring near the aortic bifurcation. In recent years, new non-invasive techniques, such as stenting, have been used to treat these AAAs. However, the development of these implants, aimed at stopping the growth of the aneurysm, has been hampered by the lack of understanding of the effect that the hemodynamic forces have on the growth mechanism. Since current in-vivo measuring techniques lack the precision and the necessary resolution, we have performed measurements of the pressure and shear stresses in laboratory models. The models of the AAA were obtained from high resolution three-dimensional CAT/SCANS performed in patients at early stages of the disease. Preliminary DPIV measurements show that the pulsatile blood flow discharging into the cavity of the aneurysm leads to large spikes of pressure and wall shear stresses near and around its distal end, indicating a possible correlation between the regions of high wall shear stresses and the observed location of the growth of the aneurysm.

  7. Successful application of a PressureWire retrogradely across an ATS prosthetic aortic valve to diagnose constrictive pericarditis.

    PubMed

    Palmer, Sonny; Mariani, Justin A; Newcomb, Andrew; Stokes, Michael B; Burns, Andrew T

    2012-01-01

    Assessment of the left ventricular pressure measured across an aortic valve prosthesis is occasionally necessary when noninvasive imaging and Doppler echocardiographic data are inconclusive or differ from the clinical findings for specific scenarios, such as diagnosing constrictive or restrictive physiology. We present a case in which we safely and effectively replicate the previous successful application of a PressureWire in diagnosing constrictive pericarditis in a patient with a bileafltet mechanical aortic and mitral valves.

  8. Ultrasound Screening for Abdominal Aortic Aneurysm

    PubMed Central

    2006-01-01

    Executive Summary Objective The aim of this review was to assess the effectiveness of ultrasound screening for asymptomatic abdominal aortic aneurysm (AAA). Clinical Need Abdominal aortic aneurysm is a localized abnormal dilatation of the aorta greater than 3 cm. In community surveys, the prevalence of AAA is reported to be between 2% and 5.4%. Abdominal aortic aneurysms are found in 4% to 8% of older men and in 0.5% to 1.5% of women aged 65 years and older. Abdominal aortic aneurysms are largely asymptomatic. If left untreated, the continuing extension and thinning of the vessel wall may eventually result in rupture of the AAA. Often rupture may occur without warning, causing acute pain. Rupture is always life threatening and requires emergency surgical repair of the ruptured aorta. The risk of death from ruptured AAA is 80% to 90%. Over one-half of all deaths attributed to a ruptured aneurysm take place before the patient reaches hospital. In comparison, the rate of death in people undergoing elective surgery is 5% to 7%; however, symptoms of AAA rarely occur before rupture. Given that ultrasound can reliably visualize the aorta in 99% of the population, and its sensitivity and specificity for diagnosing AAA approaches 100%, screening for aneurysms is worth considering as it may reduce the incidence of ruptured aneurysms and hence reduce unnecessary deaths caused by AAA-attributable mortality. Review Strategy The Medical Advisory Secretariat used its standard search strategy to retrieve international health technology assessments and English-language journal articles from selected databases to determine the effectiveness of ultrasound screening for abdominal aortic aneurysms. Case reports, letters, editorials, nonsystematic reviews, non-human studies, and comments were excluded. Questions asked: Is population-based AAA screening effective in improving health outcomes in asymptomatic populations? Is AAA screening acceptable to the population? Does this affect the

  9. Novel Molecular Imaging Approaches to Abdominal Aortic Aneurysm Risk Stratification.

    PubMed

    Toczek, Jakub; Meadows, Judith L; Sadeghi, Mehran M

    2016-01-01

    Selection of patients for abdominal aortic aneurysm repair is currently based on aneurysm size, growth rate, and symptoms. Molecular imaging of biological processes associated with aneurysm growth and rupture, for example, inflammation and matrix remodeling, could improve patient risk stratification and lead to a reduction in abdominal aortic aneurysm morbidity and mortality. (18)F-fluorodeoxyglucose-positron emission tomography and ultrasmall superparamagnetic particles of iron oxide magnetic resonance imaging are 2 novel approaches to abdominal aortic aneurysm imaging evaluated in clinical trials. A variety of other tracers, including those that target inflammatory cells and proteolytic enzymes (eg, integrin αvβ3 and matrix metalloproteinases), have proven effective in preclinical models of abdominal aortic aneurysm and show great potential for clinical translation.

  10. Advancements in identifying biomechanical determinants for abdominal aortic aneurysm rupture.

    PubMed

    Kontopodis, Nikolaos; Metaxa, Eleni; Papaharilaou, Yannis; Tavlas, Emmanouil; Tsetis, Dimitrios; Ioannou, Christos

    2015-02-01

    Abdominal aortic aneurysms are a common health problem and currently the need for surgical intervention is determined based on maximum diameter and growth rate criteria. Since these universal variables often fail to predict accurately every abdominal aortic aneurysms evolution, there is a considerable effort in the literature for other markers to be identified towards individualized rupture risk estimations and growth rate predictions. To this effort, biomechanical tools have been extensively used since abdominal aortic aneurysm rupture is in fact a material failure of the diseased arterial wall to compensate the stress acting on it. The peak wall stress, the role of the unique geometry of every individual abdominal aortic aneurysm as well as the mechanical properties and the local strength of the degenerated aneurysmal wall, all confer to rupture risk. In this review article, the assessment of these variables through mechanical testing, advanced imaging and computational modeling is reviewed and the clinical perspective is discussed.

  11. Quantitative Assessment of Abdominal Aortic Aneurysm Geometry

    PubMed Central

    Shum, Judy; Martufi, Giampaolo; Di Martino, Elena; Washington, Christopher B.; Grisafi, Joseph; Muluk, Satish C.; Finol, Ender A.

    2011-01-01

    Recent studies have shown that the maximum transverse diameter of an abdominal aortic aneurysm (AAA) and expansion rate are not entirely reliable indicators of rupture potential. We hypothesize that aneurysm morphology and wall thickness are more predictive of rupture risk and can be the deciding factors in the clinical management of the disease. A non-invasive, image-based evaluation of AAA shape was implemented on a retrospective study of 10 ruptured and 66 unruptured aneurysms. Three-dimensional models were generated from segmented, contrast-enhanced computed tomography images. Geometric indices and regional variations in wall thickness were estimated based on novel segmentation algorithms. A model was created using a J48 decision tree algorithm and its performance was assessed using ten-fold cross validation. Feature selection was performed using the χ2-test. The model correctly classified 65 datasets and had an average prediction accuracy of 86.6% (κ = 0.37). The highest ranked features were sac length, sac height, volume, surface area, maximum diameter, bulge height, and intra-luminal thrombus volume. Given that individual AAAs have complex shapes with local changes in surface curvature and wall thickness, the assessment of AAA rupture risk should be based on the accurate quantification of aneurysmal sac shape and size. PMID:20890661

  12. Percutaneous Zenith endografting for abdominal aortic aneurysms.

    PubMed

    Heyer, Kamaldeep S; Resnick, Scott A; Matsumura, Jon S; Amaranto, Daniel; Eskandari, Mark K

    2009-03-01

    A completely percutaneous approach to infrarenal abdominal aortic aneurysm (AAA) endografting has the theoretic benefits of being minimally invasive and more expedient. Our goal was to demonstrate the utility of this approach using a suprarenal fixation device and a suture-mediated closure system. We conducted a single-institution, retrospective review of 14 patients who underwent percutaneous AAA repair with the Zenith device between August 2003 and March 2007. Immediate and delayed access-related outcomes were examined over a mean follow-up of 12.1+/-2.0 months. Mean AAA size was 5.6 cm. Immediate arterial closure and technical success rate was 96% (27/28 vessels). One immediate hemostatic failure required open surgical repair. Over follow-up, one vessel required operative repair for new-onset claudication. No other immediate or delayed complications (thrombosis, pseudoaneurysm, infection, or deep venous thrombosis) were detected. A percutaneous approach for the treatment of AAA has several advantages over femoral artery cutdown but also has its own unique set of risks in the immediate and late postoperative period. Ultimately, the "preclose technique" can be safely applied for the Zenith device despite its large-bore delivery system.

  13. Endovascular treatment of abdominal aortic aneurysms

    PubMed Central

    Buck, Dominique B.; van Herwaarden, Joost A.; Schermerhorn, Marc L.; Moll, Frans L.

    2014-01-01

    Patients with abdominal aortic aneurysms (AAAs) are usually treated with endovascular aneurysm repair (EVAR), which has become the standard of care in many hospitals for patients with suitable anatomy. Clinical evidence indicates that EVAR is associated with superior perioperative outcomes and similar long-term survival compared with open repair. Since the randomized, controlled trials that provided this evidence were conducted, however, the stent graft technology for infrarenal AAA has been further developed. Improvements include profile downsizing, optimization of sealing and fixation, and the use of low porosity fabrics. In addition, imaging techniques have improved, enabling better preoperative planning, stent graft placement, and postoperative surveillance. Also in the past few years, fenestrated and branched stent grafts have increasingly been used to manage anatomically challenging aneurysms, and experiments with off-label use of stent grafts have been performed to treat patients deemed unfit or unsuitable for other treatment strategies. Overall, the indications for endovascular management of AAA are expanding to include increasingly complex and anatomically challenging aneurysms. Ongoing studies and optimization of imaging, in addition to technological refinement of stent grafts, will hopefully continue to broaden the utilization of EVAR. PMID:24343568

  14. Medical management of abdominal aortic aneurysms.

    PubMed

    Weiss, Norbert; Rodionov, Roman N; Mahlmann, Adrian

    2014-11-01

    Abdominal aortic aneurysms (AAA) are the most common arterial aneurysms. Endovascular or open surgical aneurysm repair is indicated in patients with large AAA ≥ 5.5 cm in diameter as this prevents aneurysm rupture. The presence even of small AAAs not in need of immediate repair is associated with a very high cardiovascular risk including myocardial infarction, stroke or cardiovascular death. This risk by far exceeds the risk of aneurysm rupture. These patients therefore should be considered as high-risk patients and receive optimal medical treatment and life-style modification of their cardiovascular risk factors to improve their prognosis. In addition, these patients should be followed-up for aneurysm growth and receive medical treatment to decrease aneurym progression and rupture rate. Treatment with statins has been shown to reduce cardiovascular mortality in these patients, and also slows the rate of AAA growth. Use of beta-blockers, ACE inhibitors and AT1-receptor antagonists does not affect AAA growth but may be indicated for comorbidities. Antibiotic therapy with roxithromycin has a small effect on AAA growth, but this effect must be critically weighed against the potential risk of wide-spread use of antibiotics.

  15. Abdominal aortic aneurysm repair - open - discharge

    MedlinePlus

    ... aortic aneurysm repair - open Aortic angiography Chest MRI Hardening of the ... Center-Shreveport, Shreveport, LA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla ...

  16. Acute abdominal aortic thrombosis following the Heimlich maneuver.

    PubMed

    Ayerdi, Juan; Gupta, Sushil K; Sampson, Lawrence N; Deshmukh, Narayan

    2002-04-01

    Complications from the Heimlich maneuver are relatively infrequent. Two fatal cases of abdominal aortic thrombosis have been reported following this technique. We report on the first patient that suffered an acute thrombosis of the abdominal aorta and survived. Prompt recognition of this complication provides the only hope of survival from this rare and catastrophic complication.

  17. 3D image analysis of abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Subasic, Marko; Loncaric, Sven; Sorantin, Erich

    2002-05-01

    This paper presents a method for 3-D segmentation of abdominal aortic aneurysm from computed tomography angiography images. The proposed method is automatic and requires minimal user assistance. Segmentation is performed in two steps. First inner and then outer aortic border is segmented. Those two steps are different due to different image conditions on two aortic borders. Outputs of these two segmentations give a complete 3-D model of abdominal aorta. Such a 3-D model is used in measurements of aneurysm area. The deformable model is implemented using the level-set algorithm due to its ability to describe complex shapes in natural manner which frequently occur in pathology. In segmentation of outer aortic boundary we introduced some knowledge based preprocessing to enhance and reconstruct low contrast aortic boundary. The method has been implemented in IDL and C languages. Experiments have been performed using real patient CTA images and have shown good results.

  18. Inflammatory abdominal aortic aneurysm: a persistent painful hip

    PubMed Central

    Baskaran, Dinnish; Ashraf, Nadeem; Ahmad, Adil; Menon, Jay

    2013-01-01

    The presentation of an abdominal aortic aneurysm (AAA) with isolated hip pain is a rare phenomenon. We present an atypical case of a 58-year-old previously fit man who presented with a 6-month history of progressively worsening left hip pain associated with unintentional weight loss, tender bilateral testicular swellings and a large non-tender palpable mass on abdominal examination. Urgent abdominal CT scan findings revealed a 15 cm infrarenal abdominal aortic aneurysm extending to the aortic bifurcation associated with an extensive left hydronephrosis. In theatre, the diagnosis of inflammatory AAA (IAAA) was confirmed following the presence of pyuria and a successful repair with an open approach using a bifurcated dacron graft was performed. PMID:24038286

  19. Inflammatory abdominal aortic aneurysm: a persistent painful hip.

    PubMed

    Baskaran, Dinnish; Ashraf, Nadeem; Ahmad, Adil; Menon, Jay

    2013-09-13

    The presentation of an abdominal aortic aneurysm (AAA) with isolated hip pain is a rare phenomenon. We present an atypical case of a 58-year-old previously fit man who presented with a 6-month history of progressively worsening left hip pain associated with unintentional weight loss, tender bilateral testicular swellings and a large non-tender palpable mass on abdominal examination. Urgent abdominal CT scan findings revealed a 15 cm infrarenal abdominal aortic aneurysm extending to the aortic bifurcation associated with an extensive left hydronephrosis. In theatre, the diagnosis of inflammatory AAA (IAAA) was confirmed following the presence of pyuria and a successful repair with an open approach using a bifurcated dacron graft was performed.

  20. Ruptured abdominal aortic aneurysm and aortoiliac vein fistula.

    PubMed

    Gyoten, Takayuki; Doi, Toshio; Yamashita, Akio; Fukahara, Kazuaki; Kotoh, Keiju; Yoshimura, Naoki

    2015-05-01

    A 67-year-old man was admitted with severe abdominal pain and back pain. Computed tomography showed an infrarenal abdominal aortic aneurysm (8.4 × 8.3 cm) and a large retroperitoneal hematoma. Immediately afterwards, the patient suffered circulatory collapse and was rushed to the operating theater. A fistula communicating with the left iliac vein was found. It was repaired with a Dacron patch while balloon-tipped catheters controlled the bleeding. The abdominal aortic aneurysm was replaced with a bifurcated graft. The postoperative course was uneventful. There have been few reports of successful repair of a ruptured abdominal aortic aneurysm associated with aortoiliac arteriovenous fistula.

  1. Aortic angiography

    MedlinePlus

    ... to: Abdominal aortic aneurysm Aortic dissection Aortic regurgitation Aortic stenosis Congenital (present from birth) problems Double aortic arch ... Aortic aneurysm repair - endovascular Aortic dissection Aortic insufficiency Aortic stenosis Magnetic resonance ... Patient Instructions Abdominal ...

  2. Factors involved in the antinatriuretic effects of acute constriction of the thoracic and abdominal inferior vena cava.

    NASA Technical Reports Server (NTRS)

    Schrier, R. W.; Humphreys, M. H.

    1971-01-01

    Study of the antinatriuretic effect of acute thoracic inferior vena cava (TIVC) constriction in the absence of alterations in renal perfusion pressure. A comparison is made of the effects of equivalent degrees of TIVC and abdominal inferior vena cava constriction on arterial pressure, renal hemodynamics, and electrolyte excretion.

  3. Acute Type B Aortic Dissection in a Patient with Previous Endovascular Abdominal Aortic Aneurysm Repair

    PubMed Central

    Park, Sung Hun; Rha, Seung-Woon

    2017-01-01

    Endovascular aortic repair (EVAR) was relatively safe, and became a widely performed procedure. If aortic dissection (AD) occurred in patient with previous EVAR, it could cause fatal complications like endograft collapse. Surgical treatment was limited in this situation for comorbidities and complex anatomies. Here we report a rare case of acute type B AD developed following trans-radial coronary intervention in a patient with previous EVAR of abdominal aortic aneurysm, which was treated with thoracic EVAR. PMID:28377913

  4. Open Abdominal Aortic Aneurysm Replacement in the Awake Patient.

    PubMed

    Meecham, L; Torrance, A; Vijay, S; Burtenshaw, A; Downing, R

    2017-03-01

    Nonintubated aortic surgery using various techniques has been reported, but despite publication of favorable outcomes in select patient groups, awake aortic surgery remains unpopular. Our patient had an abdominal aortic aneurysm that was unsuitable for endovascular repair. Because of the significant respiratory disease, general anesthesia represented an unacceptably high risk. As a result, he underwent open AAA repair via a retroperitoneal approach with the aid of epidural anesthesia. Here, we highlight the benefits of the procedure which offer a select cohort of patients the chance of life-saving surgery.

  5. Adventitial vasa vasorum arteriosclerosis in abdominal aortic aneurysm.

    PubMed

    Tanaka, Hiroki; Zaima, Nobuhiro; Sasaki, Takeshi; Hayasaka, Takahiro; Goto-Inoue, Naoko; Onoue, Kenji; Ikegami, Koji; Morita, Yoshifumi; Yamamoto, Naoto; Mano, Yuuki; Sano, Masaki; Saito, Takaaki; Sato, Kohji; Konno, Hiroyuki; Setou, Mitsutoshi; Unno, Naoki

    2013-01-01

    Abdominal aortic aneurysm (AAA) is a common disease among elderly individuals. However, the precise pathophysiology of AAA remains unknown. In AAA, an intraluminal thrombus prevents luminal perfusion of oxygen, allowing only the adventitial vaso vasorum (VV) to deliver oxygen and nutrients to the aortic wall. In this study, we examined changes in the adventitial VV wall in AAA to clarify the histopathological mechanisms underlying AAA. We found marked intimal hyperplasia of the adventitial VV in the AAA sac; further, immunohistological studies revealed proliferation of smooth muscle cells, which caused luminal stenosis of the VV. We also found decreased HemeB signals in the aortic wall of the sac as compared with those in the aortic wall of the neck region in AAA. The stenosis of adventitial VV in the AAA sac and the malperfusion of the aortic wall observed in the present study are new aspects of AAA pathology that are expected to enhance our understanding of this disease.

  6. Endovascular treatment of spontaneous isolated abdominal aortic dissection

    PubMed Central

    Giribono, Anna Maria; Ferrara, Doriana; Spalla, Flavia; Narese, Donatella; Bracale, Umberto; Pecoraro, Felice; Bracale, Renata; del Guercio, Luca

    2016-01-01

    Isolated abdominal aortic dissection is a rare clinical disease representing only 1.3% of all dissections. There are a few case series reported in the literature. The causes of this pathology can be spontaneous, iatrogenic, or traumatic. Most patients are asymptomatic and symptoms are usually abdominal or back pain, while claudication and lower limb ischemia are rare. Surgical and endovascular treatment are two valid options with acceptable results. We herein describe nine cases of symptomatic spontaneous isolated abdominal aortic dissection, out of which four successfully were treated with an endovascular approach between July 2003 and July 2013. All patients were men, smokers, symptomatic (either abdominal or back pain or lower limb ischemia), with a history of high blood pressure, with a medical history negative for concomitant aneurysmatic dilatation or previous endovascular intervention. Diagnosis of isolated abdominal aortic dissection were established by contrast-enhanced computed tomography angiography (CTA) of the thoracic and abdominal aorta. All nine patients initially underwent medical treatment. In four symptomatic cases, non-responsive to medical therapy, bare-metal stents or stent grafts were successfully positioned. All patients completed a CTA follow-up of at least 12 months, during which they remained symptom-free. Endovascular management of this condition is associated with a high rate of technical success and a low mortality; therefore, it can be considered the treatment of choice when it is feasible. PMID:27994881

  7. [Pseudomembranous colitis after surgery for a ruptured abdominal aortic aneurysm].

    PubMed

    Lozano Sánchez, F; Sánchez Fernández, J; Palacios, E; Fernández, M; Ingelmo Morin, A; Gómez Alonso, A

    1993-01-01

    We present a rare postoperative complication after surgical procedures for rupture of abdominal aortic aneurysms. The disease, a pseudomembranous colitis, was early recognized (by evidence of clostridium difficile after a coprocultive) and satisfactorily treated with vancomycin. From the literature review we found only a similar case but results were absolutely different from our case.

  8. Influence of Abdominal Aortic Aneurysm Shape on Hemodynamics

    DTIC Science & Technology

    2014-09-19

    know to promote atherosclerosis . 1 Introduction The vascular condition known as abdominal aortic aneurysm (AAA) is a dilatation of at least 1.5 times...flow with oscillat- ing WSS is associated with atherosclerosis (Tarbell et al. 2014). Evidence also suggests that high WSS with sharp spacial gradients

  9. Complications of Endovascular Repair of Abdominal Aortic Aneurysms: A Review

    SciTech Connect

    Katzen, Barry T. MacLean, Alexandra A.

    2006-12-15

    The endovascular procedure for repair of abdominal aortic aneurysms has had an enormous impact on the treatment of this challenging disease. Complications, however, do occur and it is important to have a thorough understanding of the array of complications and appropriate management strategies. In this review of endovascular complications, we describe early and late complications paying particular attention to preventive, treatment and surveillance strategies.

  10. [The computed tomographic diagnosis of inflammatory abdominal aortic aneurysms].

    PubMed

    Koch, J A; Grützner, G; Jungblut, R M; Kniemeyer, H W; Mödder, U

    1994-07-01

    Amongst 1599 patients undergoing surgery for abdominal aortic aneurysm, there were 89 patients (5.6%) who showed typical features of inflammatory aneurysms of the abdominal aorta (IAAA). 37 of the 89 patients had been examined preoperatively by CT. In 73% of the cases (27/37) a correct diagnosis had been made. Localisation, width and extent of the IAAA was correctly diagnosed in all patients. Involvement of the renal arteries by the inflammatory process, the extent of thrombus and of mural calcification were accurately shown. The inflammatory tissues were typically ventral and lateral to the aorta. Frequently, there were adhesions to neighbouring structures. Aortic rupture, aortic dissection and retroperitoneal lymphoma may produce similar CT appearances; nevertheless, CT remains at present the method of choice for the diagnosis of IAAA because of its high sensitivity.

  11. Endovascular repair for abdominal aortic aneurysm followed by type B dissection.

    PubMed

    Shingaki, Masami; Kato, Masaaki; Motoki, Manabu; Kubo, Yoji; Isaji, Toshihiko; Okubo, Nobukazu

    2016-10-01

    An 86-year-old man with an abdominal aortic aneurysm was diagnosed with type B aortic dissection accompanied by a patent false lumen that started at the distal arch of the thoracic aorta and terminated at the left common iliac artery. Meticulous preoperative assessment detected 3 large intimal tears in the descending aorta, abdominal aortic aneurysm, and left common iliac artery. We performed single-stage thoracic and abdominal endovascular aneurysm repair and concomitant axillary-axillary bypass. The abdominal aortic aneurysm with type B aortic dissection was successfully treated using a single-stage endovascular stent graft, without any complications due to the careful preoperative examinations.

  12. Use of the Abdominal Aortic Tourniquet for Hemorrhage Control

    DTIC Science & Technology

    2016-06-01

    a leading preventable cause of death . This project is designed to study a new hemorrhage control device (Abdominal Aortic Tourniquet AAT) to control...injuries on the modern battlefield. Uncontrolled pelvic and inguinal bleeding is a leading preventable cause of death . The AAT is focused at this...preventable deaths not previously treatable. The solution to this problem must be stable, easy to apply and completely stop the loss of blood. The AAT

  13. Abdominal aortic thrombosis in association with an attempted Heimlich maneuver.

    PubMed

    Roehm, E F; Twiest, M W; Williams, R C

    1983-03-04

    We report herein a case of an incorrectly applied Heimlich maneuver--to the best of our knowledge, the first reported fatal complication associated with a Heimlich maneuver, acute thrombosis of an abdominal aortic aneurysm, and the distal aorta. While the Heimlich maneuver is effective for the relief of foreign body-induced upper airway obstruction, increased efforts should be directed toward instructing the public in correctly recognizing and optimally treating airway obstruction.

  14. Stent-Grafts for Unruptured Abdominal Aortic Aneurysms: Current Status

    SciTech Connect

    Rose, John

    2006-06-15

    Aortic stent-grafts were introduced at the beginning of the 1990s as a less invasive method of dealing with aortic aneurysms in patients with poor cardiovascular reserve. The numbers of procedures performed worldwide has increased exponentially despite the current lack of any substantial evidence for long-term efficacy in comparison with the gold standard of open surgical grafting. This review summarizes the evolution of the abdominal aortic stent-graft, the techniques used for assessment and deployment, and the effect of the procedure on both the patient and the device. The recent publication of two national multicenter trials has confirmed that the endovascular technique confers a 2.5-fold reduction in 30-day mortality in comparison with open surgery. However, over 4 years of follow-up, there is a 3-fold increase in the risk of reintervention and the overall costs are 30% greater with endovascular repair. Although the improvement in aneurysm-related mortality persists in the mid-term, because of the initial reduction in perioperative mortality, the all-cause mortality rate at 4 years is actually no better than for open surgery. Longer-term data from the randomized trials are awaited as well as results from the latest trials utilizing state-of-the-art devices. Whilst the overall management of abdominal aortic aneurysms has undoubtedly benefited from the introduction of stent-grafts, open repair currently remains the gold standard treatment.

  15. 3D image analysis of abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Subasic, Marko; Loncaric, Sven; Sorantin, Erich

    2001-07-01

    In this paper we propose a technique for 3-D segmentation of abdominal aortic aneurysm (AAA) from computed tomography angiography (CTA) images. Output data (3-D model) form the proposed method can be used for measurement of aortic shape and dimensions. Knowledge of aortic shape and size is very important in planning of minimally invasive procedure that is for selection of appropriate stent graft device for treatment of AAA. The technique is based on a 3-D deformable model and utilizes the level-set algorithm for implementation of the method. The method performs 3-D segmentation of CTA images and extracts a 3-D model of aortic wall. Once the 3-D model of aortic wall is available it is easy to perform all required measurements for appropriate stent graft selection. The method proposed in this paper uses the level-set algorithm for deformable models, instead of the classical snake algorithm. The main advantage of the level set algorithm is that it enables easy segmentation of complex structures, surpassing most of the drawbacks of the classical approach. We have extended the deformable model to incorporate the a priori knowledge about the shape of the AAA. This helps direct the evolution of the deformable model to correctly segment the aorta. The algorithm has been implemented in IDL and C languages. Experiments have been performed using real patient CTA images and have shown good results.

  16. Intraoperative Sac Pressure Measurement During Endovascular Abdominal Aortic Aneurysm Repair

    SciTech Connect

    Ishibashi, Hiroyuki; Ishiguchi, Tsuneo; Ohta, Takashi; Sugimoto, Ikuo; Iwata, Hirohide; Yamada, Tetsuya; Tadakoshi, Masao; Hida, Noriyuki; Orimoto, Yuki; Kamei, Seiji

    2010-10-15

    PurposeIntraoperative sac pressure was measured during endovascular abdominal aortic aneurysm repair (EVAR) to evaluate the clinical significance of sac pressure measurement.MethodsA microcatheter was placed in an aneurysm sac from the contralateral femoral artery, and sac pressure was measured during EVAR procedures in 47 patients. Aortic blood pressure was measured as a control by a catheter from the left brachial artery.ResultsThe systolic sac pressure index (SPI) was 0.87 {+-} 0.10 after main-body deployment, 0.63 {+-} 0.12 after leg deployment (P < 0.01), and 0.56 {+-} 0.12 after completion of the procedure (P < 0.01). Pulse pressure was 55 {+-} 21 mmHg, 23 {+-} 15 mmHg (P < 0.01), and 16 {+-} 12 mmHg (P < 0.01), respectively. SPI showed no significant differences between the Zenith and Excluder stent grafts (0.56 {+-} 0.13 vs. 0.54 {+-} 0.10, NS). Type I endoleak was found in seven patients (15%), and the SPI decreased from 0.62 {+-} 0.10 to 0.55 {+-} 0.10 (P = 0.10) after fixing procedures. Type II endoleak was found in 12 patients (26%) by completion angiography. The SPI showed no difference between type II endoleak positive and negative (0.58 {+-} 0.12 vs. 0.55 {+-} 0.12, NS). There were no significant differences between the final SPI of abdominal aortic aneurysms in which the diameter decreased in the follow-up and that of abdominal aortic aneurysms in which the diameter did not change (0.53 {+-} 0.12 vs. 0.57 {+-} 0.12, NS).ConclusionsSac pressure measurement was useful for instant hemodynamic evaluation of the EVAR procedure, especially in type I endoleaks. However, on the basis of this small study, the SPI cannot be used to reliably predict sac growth or regression.

  17. Improving the efficiency of abdominal aortic aneurysm wall stress computations.

    PubMed

    Zelaya, Jaime E; Goenezen, Sevan; Dargon, Phong T; Azarbal, Amir-Farzin; Rugonyi, Sandra

    2014-01-01

    An abdominal aortic aneurysm is a pathological dilation of the abdominal aorta, which carries a high mortality rate if ruptured. The most commonly used surrogate marker of rupture risk is the maximal transverse diameter of the aneurysm. More recent studies suggest that wall stress from models of patient-specific aneurysm geometries extracted, for instance, from computed tomography images may be a more accurate predictor of rupture risk and an important factor in AAA size progression. However, quantification of wall stress is typically computationally intensive and time-consuming, mainly due to the nonlinear mechanical behavior of the abdominal aortic aneurysm walls. These difficulties have limited the potential of computational models in clinical practice. To facilitate computation of wall stresses, we propose to use a linear approach that ensures equilibrium of wall stresses in the aneurysms. This proposed linear model approach is easy to implement and eliminates the burden of nonlinear computations. To assess the accuracy of our proposed approach to compute wall stresses, results from idealized and patient-specific model simulations were compared to those obtained using conventional approaches and to those of a hypothetical, reference abdominal aortic aneurysm model. For the reference model, wall mechanical properties and the initial unloaded and unstressed configuration were assumed to be known, and the resulting wall stresses were used as reference for comparison. Our proposed linear approach accurately approximates wall stresses for varying model geometries and wall material properties. Our findings suggest that the proposed linear approach could be used as an effective, efficient, easy-to-use clinical tool to estimate patient-specific wall stresses.

  18. Thrombus Volume Change Visualization after Endovascular Abdominal Aortic Aneurysm Repair

    NASA Astrophysics Data System (ADS)

    Maiora, Josu; García, Guillermo; Macía, Iván; Legarreta, Jon Haitz; Boto, Fernando; Paloc, Céline; Graña, Manuel; Abuín, Javier Sanchez

    A surgical technique currently used in the treatment of Abdominal Aortic Aneurysms (AAA) is the Endovascular Aneurysm Repair (EVAR). This minimally invasive procedure involves inserting a prosthesis in the aortic vessel that excludes the aneurysm from the bloodstream. The stent, once in place acts as a false lumen for the blood current to travel down, and not into the surrounding aneurysm sac. This procedure, therefore, immediately takes the pressure off the aneurysm, which thromboses itself after some time. Nevertheless, in a long term perspective, different complications such as prosthesis displacement or bloodstream leaks into or from the aneurysmatic bulge (endoleaks) could appear causing a pressure elevation and, as a result, increasing the danger of rupture. The purpose of this work is to explore the application of image registration techniques to the visual detection of changes in the thrombus in order to assess the evolution of the aneurysm. Prior to registration, both the lumen and the thrombus are segmented

  19. Effectiveness of screening for abdominal aortic aneurysm during echocardiography.

    PubMed

    Aboyans, Victor; Bataille, Vincent; Bliscaux, Pascale; Ederhy, Stéphane; Filliol, Didier; Honton, Benjamin; Kurtz, Baptiste; Messas, Emmanuel; Mohty, Dania; Brochet, Eric; Kownator, Serge

    2014-10-01

    Screening patients with abdominal aortic aneurysm (AAA) is associated with reduced AAA-related mortality, but population screening is poorly implemented. Opportunistic screening during imaging for other indications might be efficient. Single-center series reported AAA rates of 0.8% to 6.5% in patients undergoing transthoracic echocardiography (TTE), with disparities due to selection bias. In this first multicenter study, we aimed to assess the feasibility and criteria for screening AAA during TTE in real-life practice. During a week of May 2011, 79 centers participated in a nationwide survey. All patients aged ≥65 years requiring TTE for any indication were eligible, except for those with operated abdominal aorta. We defined AAA by an anteroposterior diameter of the infrarenal aorta≥30 mm. Of 1,382 consecutive patients, abdominal aorta imaging was feasible in 96.7%, with a median delay of 1.7 minutes (>3 minutes in 3.6% of cases). We found AAA in 50 patients (3.7%). Unknown AAA (2.7%) was more frequent in men than women (3.7% vs 1.3%, respectively, p=0.007) and increased by age at 2.2%, 2.5%, and 5.8% in age bands of 65 to 74, 75 to 84, and 85+ years, respectively. None of the female participants aged <75 years had AAA. Smoking status and family history of AAA were significantly more frequent among patients with AAA. The ascending aorta was larger in those with AAA (36.2±4.7 vs 34.0±5.2 mm, p=0.006), and bicuspid aortic valve and/or major aortic regurgitation were also more frequent (8% vs 2.6%, p=0.017). In conclusion, rapid AAA screening during TTE is feasible and should be limited to men ≥65 years and women≥75 years.

  20. Inflammatory abdominal aortic aneurysm: report of seven cases.

    PubMed

    Nagahama, Hiroyuki; Nakamura, Kunihide; Matsuyama, Masakazu; Endou, Jouji; Nishimura, Masanori; Ishii, Hirohito; Yokota, Atsuko; Ikenoue, Makoto

    2013-01-01

    We reviewed 575 cases of abdominal aortic aneurysm (AAA) repair performed in our institution from 1979 to 2010. In this group, 7 (1.2%) patients (mean age, 72.6 years) had evidence of inflammatory AAA (IAAA). Mean aneurysmal diameter was 70.4 mm as measured on CT, and the mantle sign was present in all cases. They were male smokers. Two patients had hydronephrosis, and required a ureteral stent before surgery. All patients underwent laparotomy, and no perioperative deaths occured. We suggest that operative technique should be modified to avoid excessive dissection on both the proximal and distal sides of the IAAA.

  1. Unusual complications in an inflammatory abdominal aortic aneurysm.

    PubMed

    Akiyama, K; Hirota, J; Taniyasu, N; Asano, S

    1999-11-01

    An unusual case of an inflammatory abdominal aortic aneurysm (IAAA) associated with coronary aneurysms and pathological fracture of the adjacent lumbar vertebrae. The associated coronary lesions in cases of IAAA are usually occlusions. In the present case, it was concluded that a possible cause of the coronary aneurysm was coronary arteritis and the etiology of the pathological fracture of the lumbar vertebrae was occlusion of the lumbar penetrating arteries due to vasculitis resulting in aseptic necrosis. Inflammatory AAA can be associated with aneurysms in addition to occlusive disease in systemic arteries. The preoperative evaluation of systemic arterial lesions and the function of systemic organs is essential.

  2. Inflammatory Abdominal Aortic Aneurysm: Report of Seven Cases

    PubMed Central

    2013-01-01

    We reviewed 575 cases of abdominal aortic aneurysm (AAA) repair performed in our institution from 1979 to 2010. In this group, 7 (1.2%) patients (mean age, 72.6 years) had evidence of inflammatory AAA (IAAA). Mean aneurysmal diameter was 70.4 mm as measured on CT, and the mantle sign was present in all cases. They were male smokers. Two patients had hydronephrosis, and required a ureteral stent before surgery. All patients underwent laparotomy, and no perioperative deaths occured. We suggest that operative technique should be modified to avoid excessive dissection on both the proximal and distal sides of the IAAA. PMID:24386030

  3. Reduced cardiac fructose 2,6 bisphosphate increases hypertrophy and decreases glycolysis following aortic constriction.

    PubMed

    Wang, Jianxun; Xu, Jianxiang; Wang, Qianwen; Brainard, Robert E; Watson, Lewis J; Jones, Steven P; Epstein, Paul N

    2013-01-01

    This study was designed to test whether reduced levels of cardiac fructose-2,6-bisphosphate (F-2,6-P(2)) exacerbates cardiac damage in response to pressure overload. F-2,6-P(2) is a positive regulator of the glycolytic enzyme phosphofructokinase. Normal and Mb transgenic mice were subject to transverse aortic constriction (TAC) or sham surgery. Mb transgenic mice have reduced F-2,6-P(2) levels, due to cardiac expression of a transgene for a mutant, kinase deficient form of the enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK-2) which controls the level of F-2,6-P(2). Thirteen weeks following TAC surgery, glycolysis was elevated in FVB, but not in Mb, hearts. Mb hearts were markedly more sensitive to TAC induced damage. Echocardiography revealed lower fractional shortening in Mb-TAC mice as well as larger left ventricular end diastolic and end systolic diameters. Cardiac hypertrophy and pulmonary congestion were more severe in Mb-TAC mice as indicated by the ratios of heart and lung weight to tibia length. Expression of α-MHC RNA was reduced more in Mb-TAC hearts than in FVB-TAC hearts. TAC produced a much greater increase in fibrosis of Mb hearts and this was accompanied by 5-fold more collagen 1 RNA expression in Mb-TAC versus FVB-TAC hearts. Mb-TAC hearts had the lowest phosphocreatine to ATP ratio and the most oxidative stress as indicated by higher cardiac content of 4-hydroxynonenal protein adducts. These results indicate that the heart's capacity to increase F-2,6-P(2) during pressure overload elevates glycolysis which is beneficial for reducing pressure overload induced cardiac hypertrophy, dysfunction and fibrosis.

  4. Endovascular abdominal aortic aneurysm repair in the geriatric population

    PubMed Central

    Saratzis, Athanasios; Mohamed, Saif

    2012-01-01

    Abdominal aortic aneurysm (AAA) is a relatively common pathology among the elderly. More people above the age of 80 will have to undergo treatment of an AAA in the future. This review aims to summarize the literature focusing on endovascular repair of AAA in the geriatric population. A systematic review of the literature was performed, including results from endovascular abdominal aortic aneurysm repair (EVAR) registries and studies comparing open repair and EVAR in those above the age of 80. A total of 15 studies were identified. EVAR in this population is efficient with a success rate exceeding 90% in all cases, and safe, with early mortality and morbidity being superior among patients undergoing EVAR against open repair. Late survival can be as high as 95% after 5 years. Aneurysm-related death over long-term follow-up was low after EVAR, ranging from 0 to 3.4%. Endovascular repair can be offered safely in the geriatric population and seems to compare favourably with open repair in all studies in the literature to date. PMID:23097659

  5. In vivo strain assessment of the abdominal aortic aneurysm.

    PubMed

    Satriano, Alessandro; Rivolo, Simone; Martufi, Giampaolo; Finol, Ender A; Di Martino, Elena S

    2015-01-21

    The only criteria currently used to inform surgical decision for abdominal aortic aneurysms are maximum diameter (>5.5 cm) and rate of growth, even though several studies have identified the need for more specific indicators of risk. Patient-specific biomechanical variables likely to affect rupture risk would be a valuable addition to the science of understanding rupture risk and prove to be a life saving benefit for patients. Local deformability of the aorta is related to the local mechanical properties of the wall and may provide indication on the state of weakening of the wall tissue. We propose a 3D image-based approach to compute aortic wall strain maps in vivo. The method is applicable to a variety of imaging modalities that provide sequential images at different phases in the cardiac cycle. We applied the method to a series of abdominal aneurysms imaged using cine-MRI obtaining strain maps at different phases in the cardiac cycle. These maps could be used to evaluate the distensibility of an aneurysm at baseline and at different follow-up times and provide an additional index to clinicians to facilitate decisions on the best course of action for a specific patient.

  6. A Contained Ruptured Abdominal Aortic Aneurysm Presenting with Vertebral Erosion.

    PubMed

    Li, Yongqi; Li, Lei; Zhang, Dongming; Wang, Xiaomei; Sun, Weidong; Wang, Han

    2017-02-24

    Chronic contained rupture (CCR) of abdominal aortic aneurysm (AAA) with vertebral erosion is a rare condition. Although it has been reported previously, it is still liable to be misdiagnosed. We present a case of CCR of AAA with vertebral erosion. A brief analysis of similar cases reported in the last 5 years is presented. A 71-year-old male was admitted to our hospital because of severe prickling pain in his left thigh. Computerized tomography angiography revealed an AAA which had caused erosion of L3 vertebral body and the left psoas muscle. An aortotomy was performed, and the excised aortic aneurysm replaced with a Dacron graft. Postoperative computed tomography (CT) angiography indicated a normal aortic graft. The patient was discharged 13 days after the surgery. In conclusion, pain in lower back and leg could be associated with vertebral erosion caused by CCR of AAA. Ultrasonography, CT, or magnetic resonance imaging of abdomen should be routinely performed in cases of lumbago that have associated risk factors for AAA.

  7. Abdominal aortic aneurysm and histological, clinical, radiological correlation.

    PubMed

    Rodella, Luigi Fabrizio; Rezzani, Rita; Bonomini, Francesca; Peroni, Michele; Cocchi, Marco Angelo; Hirtler, Lena; Bonardelli, Stefano

    2016-04-01

    To date, the pathogenesis of abdominal aortic aneurism (AAA) still remains unclear. As such, the aim of this study was to evaluate changes of the aortic structure during AAA. We analysed the microscopic frame of vessels sections, starting from the primum movens leading to abnormal dilatation. AAA samples were collected and processed through various staining methods (Verhoeff-Van Gieson, Masson Goldner, Sirius Red). Subsequently, the vessel morphology and collagenic web of the tunica media and adventitia were determined and the amount of type I and type III collagen was measured. We also applied immune-histochemistry markers for CD34 and PGP 9.5 in order to identify vascular and nerve structures in the aorta. Immune-positivity quantification was used to calculate the percentage of the stained area. We found increasing deposition of type I collagen and reduced type III collagen in both tunica media and adventitia of AAA. The total amount of vasa vasorum, marked with CD34, and nerva vasorum, marked with PGP 9.5, was also higher in AAA samples. Cardiovascular risk factors (blood pressure, dyslipidemia, cigarette smoking) and radiological data (maximum aneurism diameter, intra-luminal thrombus, aortic wall calcification) increased these changes. These results suggest that the tunica adventitia may have a central role in the pathogenesis of AAA as clearly there are major changes characterized by rooted inflammatory infiltration. The presence of immune components could explain these modifications within the framework of the aorta.

  8. Extensive Erosion of Vertebral Bodies Due to a Chronic Contained Ruptured Abdominal Aortic Aneurysm

    PubMed Central

    Lombardi, Alecio Fernando; Cardoso, Fabiano Nassar; da Rocha Fernandes, Artur

    2016-01-01

    This report describes a case of chronically ruptured abdominal aortic aneurysm contained within the lumbar vertebral bodies that presented with dull abdominal pain. Sudden, massive hemorrhage is an uncommon, yet well-known complication of an untreated abdominal aortic aneurysm. In addition, misleading clinical and radiological findings present difficult diagnostic challenges in such cases. This report emphasizes the findings obtained with multidetector computed tomography and delineates the differentiation of this condition from similar pathologies. PMID:27200153

  9. [Abdominal aortic aneurysm treated by endovascular surgery: a case report].

    PubMed

    Alconero-Camarero, Ana Rosa; Cobo-Sánchez, José Luis; Casaus-Pérez, María; García-Campo, María Elena; García-Zarrabeitia, María José; Calvo-Diez, Marta; Mirones-Valdeolivas, Luz Elena

    2008-01-01

    An aneurysm is an abnormal dilation or irreversible convex of a portion of an artery. The most common site of aneurysms is the abdominal aorta and their appearance is often due to degeneration of the arterial wall, associated with atherosclerosis and favored by risk factors such as smoking and hypertension, among others. Left untreated, aneurysm of the abdominal aorta usually leads to rupture. Treatment is surgical, consisting of the introduction of a prosthesis, composed basically of a stent and an introducer, into the aorta. We report the case of a person diagnosed with abdominal aortic aneurysm in a routine examination who was admitted for ambulatory surgical treatment. We designed a nursing care plan, following Virginia Henderson's conceptual model. The care plan was divided into 2 parts, a first preoperative phase and a second postimplantation or monitoring phase. The care plan contained the principal nursing diagnoses, based on the taxonomies of the North American Nursing Diagnosis Association (NANDA), nursing interventions classification (NIC) and nursing outcomes classifications (NOC), and collaboration problems/potential complications. The patient was discharged to home after contact was made with his reference nurse in the primary health center, since during the hospital phase, some NOC indicators remained unresolved.

  10. Endovascular Treatment of Ruptured Abdominal Aortic Aneurysm with Aortocaval Fistula

    SciTech Connect

    Guzzardi, Giuseppe Fossaceca, Rita; Divenuto, Ignazio; Musiani, Antonello; Brustia, Piero; Carriero, Alessandro

    2010-08-15

    Aortocaval fistula (ACF) is a rare complication of abdominal aortic aneurysm (AAA). We report the endovascular repair of an AAA rupture into the inferior vena cava. A 78-year-old woman was admitted to our hospital for acute hypotension. She presented with a pulsatile abdominal mass and became rapidly anuric. Abdominal computed tomography (CT) showed an AAA rupture into the inferior vena cava. The features of the AAA made it suitable for endovascular repair. To prevent pulmonary embolism caused by the presence of sac thrombosis near the vena cava lumen, a temporary vena cava filter was deployed before the procedure. A bifurcated stent-graft was placed with the patient under local anaesthesia, and the AAA was successfully treated. A transient type II endoleak was detected on CT 3 days after endograft placement. At routine follow-up 6 and 12 months after the procedure, the patient was in good clinical condition, and the type II endoleak had sealed completely. Endovascular treatment offers an attractive therapeutic alternative to open repair in case of ACF; however, only small numbers of patients have been treated, and long-term follow-up interval is lacking.

  11. Reproducibility of aortic pulsatility measurements from ECG-gated abdominal CTA in patients with abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Manduca, Armando; Fletcher, Joel G.; Wentz, Robert J.; Shields, Raymond C.; Vrtiska, Terri J.; Siddiki, Hassan; Nielson, Theresa

    2009-02-01

    Purpose: ECG-gated abdominal CT angiography with reconstruction of multiple, temporally overlapping CT angiography datasets has been proposed for measuring aortic pulsatility. The purpose of this work is to develop algorithms to segment the aorta from surrounding structures from CTA datasets across cardiac phases, calculate registered centerlines and measurements of regional aortic pulsatility in patients with AAA, and to assess the reproducibility of these measurements. Methods: ECG-gated CTA was performed with a temporal resolution of 165 ms, reconstructed to 1 mm slices ranging at 14 cardiac phase points. Data sets were obtained from 17 patients on which two such scans were performed 6 to 12 months apart. Automated segmentation, centerline generation, and registration of centerlines between phases was performed, followed by calculation of cross-sectional areas and regional and local pulsatility. Results: Pulsatility calculations for the supraceliac region were very reproducible between earlier and later scans of the same patient, with average differences less than 1% for pulsatility values ranging from 2% to 13%. Local radial pulsatilities were also reproducible to within ~1%. Aneurysm volume changes between scans can also be quantified. Conclusion: Automated segmentation, centerline generation, and registration of temporally resolved CTA datasets permit measurements of regional changes in cross-sectional area over the course of the cardiac cycle (i.e., regional aortic pulsatility). These measurements are reproducible between scans 6-12 months apart, with differences in aortic areas reflecting both aneurysm remodeling and changes in blood pressure. Regional pulsatilities ranged from 2 to 13% but were reproducible at the 1% level.

  12. Infected abdominal aortic aneurysm due to Escherichia coli.

    PubMed

    Bouzas, Miguel; Tchana-Sato, Vincent; Lavigne, Jean Paul

    2016-10-19

    Early diagnosis of infected abdominal aortic aneurysm (IAAA) is still a medical challenge due to its diverse and non-specific symptoms and signs. The most common responsible pathogens are Salmonella, Staphylococcus, Campylobacter and Streptococcus species. The authors report the case of a 67-year-old man, admitted for high fever and finally diagnosed with Escherichia coli (E.coli)-related IAAA. The IAAA ruptured during the general anaesthesia induction, leading to an emergency surgery. The authors successfully proceeded to an open aneurysmectomy with extensive debridement and in situ graft replacement. This case emphasizes the potential for rapid IAAA expansion, its high-rupture risk and the importance of computed tomography as a diagnostic tool.

  13. Hybrid Treatment of Acute Abdominal Aortic Thrombosis Presenting with Paraplegia.

    PubMed

    Azzarone, Matteo; De Troia, Alessandro; Iazzolino, Luigi; Nabulsi, Bilal; Tecchio, Tiziano

    2016-05-01

    Acute thrombotic or embolic occlusion of the abdominal aorta is a rare vascular emergency associated with high morbidity and mortality rates. Classically, the clinical presentation is a severe peripheral ischemia with bilateral leg pain as the predominant feature. Aortic occlusion presenting as an isolated acute onset of paraplegia due to spinal cord ischemia is very rare and requires improved awareness to prevent adverse outcomes associated with delayed diagnosis. We report the case of a 54-year-old man who presented with sudden paraplegia due to the thrombotic occlusion of the infrarenal aorta involving the first segment of the common iliac arteries on both sides; emergent transperitoneal aorto iliac thrombectomy combined with the endovascular iliac kissing-stent technique were performed achieving perioperative complete regression of the symptoms.

  14. Abdominal aortic aneurysm-an independent disease to atherosclerosis?

    PubMed

    Toghill, Bradley J; Saratzis, Athanasios; Bown, Matthew J

    Atherosclerosis and abdominal aortic aneurysms (AAAs) are multifactorial and polygenic diseases with known environmental and genetic risk factors that contribute toward disease development. Atherosclerosis represents an important independent risk factor for AAA, as people with AAA often have atherosclerosis. Studies have shown that comorbidity is usually between ~25% and 55%, but it is still not fully known whether this association is causal or a result of common shared risk profiles. Most recent epidemiological, clinical, and biological evidence suggests that the two pathologies are more distinct than traditionally thought. For instance diabetes mellitus, hypercholesterolemia, and obesity are high risk for atherosclerosis development but are not as pronounced in AAA, whereas smoking, gender, and ethnicity are particularly high risk for AAA but less so for atherosclerosis. In addition, genetic and epigenetic studies have identified independent risk loci involved in AAA susceptibility that are not associated with other cardiovascular diseases, and research on important common cardiovascular biomarkers has illustrated discrepancies in those with AAA.

  15. Ultrasonography Performed by Primary Care Residents for Abdominal Aortic Aneurysm Screening

    PubMed Central

    Bailey, Raymond P; Ault, Mark; Greengold, Nancy L; Rosendahl, Thomas; Cossman, David

    2001-01-01

    A prospective pilot study was undertaken to assess a protocol to educate primary care residents in how to personally perform ultrasonography for abdominal aortic aneurysm screening. Resident exams were proctored by a primary care physician trained in ultrasonography and were scored on the level of competence in doing the examination. Patients had ultrasound performed by a resident, followed by repeat examination by the vascular lab. Primary care resident abdominal aortic imaging was achieved in 79 of 80 attempts. Four abdominal aortic aneurysms were identified. There were 75 normal examinations; resident ultrasonography results were consistent with the results of the vascular lab. Ten residents achieved an abdominal aortic ultrasound-independent competence level after an average of 3.4 proctored exams. The main outcome of this study is that a primary care resident, with minimal training in ultrasonography imaging, is able to rapidly learn the technique of ultrasonography imaging of the abdominal aorta. PMID:11903764

  16. [Inflammatory abdominal aortic aneurysm. Role of corticosteroid therapy].

    PubMed

    Testart, J; Plissonnier, D; Peillon, C; Watelet, J

    2000-06-01

    For more than 20 years it has been generally acknowledged that operation for inflammatory abdominal aortic aneurysm (IAAA) using the common in-lay-graft procedure will induce the regression of peri-aortic fibrosis. However in prospective studies, after a 2 years follow-up, no regression appeared in approximated 8% of the cases (table I). Moreover in some IAAA a corticosteroid treatment (CS) was prescribed and it produced a regression of fibrosis and therefore facilitated the operation. Nevertheless the usefulness of the CS remains debated. We report 4 new cases of IAAA with CS. Based on our cases and an analysis of the literature we conclude that when there is no urgency to operate (diameter inferior to 50 mm) CS is the best option in IAAA with either severe inflammation or ureter involvement. Due to the regression of the fibrosis it can facilitate the surgical procedure. However it needs to be conducted with an adequate dose and duration. Finally the CS is the only possibility when the inflammation persist following the treatment of the IAAA.

  17. Heme Oxygenase-1 Expression Affects Murine Abdominal Aortic Aneurysm Progression

    PubMed Central

    Azuma, Junya; Wong, Ronald J.; Morisawa, Takeshi; Hsu, Mark; Maegdefessel, Lars; Zhao, Hui; Kalish, Flora; Kayama, Yosuke; Wallenstein, Matthew B.; Deng, Alicia C.; Spin, Joshua M.; Stevenson, David K.; Dalman, Ronald L.; Tsao, Philip S.

    2016-01-01

    Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is a cytoprotective enzyme upregulated in the vasculature by increased flow and inflammatory stimuli. Human genetic data suggest that a diminished HO-1 expression may predispose one to abdominal aortic aneurysm (AAA) development. In addition, heme is known to strongly induce HO-1 expression. Utilizing the porcine pancreatic elastase (PPE) model of AAA induction in HO-1 heterozygous (HO-1+/-, HO-1 Het) mice, we found that a deficiency in HO-1 leads to augmented AAA development. Peritoneal macrophages from HO-1+/- mice showed increased gene expression of pro-inflammatory cytokines, including MCP-1, TNF-alpha, IL-1-beta, and IL-6, but decreased expression of anti-inflammatory cytokines IL-10 and TGF-beta. Furthermore, treatment with heme returned AAA progression in HO-1 Het mice to a wild-type profile. Using a second murine AAA model (Ang II-ApoE-/-), we showed that low doses of the HMG-CoA reductase inhibitor rosuvastatin can induce HO-1 expression in aortic tissue and suppress AAA progression in the absence of lipid lowering. Our results support those studies that suggest that pleiotropic statin effects might be beneficial in AAA, possibly through the upregulation of HO-1. Specific targeted therapies designed to induce HO-1 could become an adjunctive therapeutic strategy for the prevention of AAA disease. PMID:26894432

  18. [Genetic aspects of the pathogenesis of aortic abdominal aneurysms].

    PubMed

    Waliszewski, Krzysztof; Słomski, Ryszard; Oszkinis, Grzegorz; Majewski, Wacław

    2005-01-01

    In industrialized countries the number of abdominal aortic aneurysms (AAA) is continuously rising. In recent years the mortality rate tripled and it is the number 13 cause of death in United States. Despite many identified risk factors and understanding of their pathomechanisms, the pathogenesis of AAA remains unclear. Thanks to the epidemiological researches and improvement of molecular techniques it was noted that AAA may have a genetic bases. The diversity between the possible genomic defects that could lead to the development of aneurytic changes was also suggested. This has a direct relationship with the complexity of the aortic wall structure and therefore with the number of potential injury locations. Current genetic research confirms the changes in expression and the many polymorphic variants of genes coding structural and enzymatic proteins. Thus, AAA seems to be a disease with multifactor pathogenesis and numerous possible genome anomaly variants. Hence, it seems that the complete understanding of the genetic bases of AAA continuous to be distant. However, efforts in this matter remain valuable, giving hope for an improved diagnosis, prophylaxis and treatment of this disease. This article is a review of the available knowledge regarding the genetic origin of AAA.

  19. Abdominal aortic aneurysms: how can we improve their treatment?

    PubMed Central

    Scobie, T K

    1980-01-01

    Arteriosclerotic abdominal aortic aneurysms are present in a least 2% of the elderly population of the Western world and their number is increasing. Without treatment 30% of patients with asymptomatic aneurysms live for 5 years, although the risk of rupture becomes greater as the size of the aneurysm increases. Of those with untreated symptomatic aneurysms 80% are dead within a year. Elective repair of aneurysms has a low mortality, and 50% of the patients live for at least 5 years. Symptomatic aneurysms all cause pain and may produce other symptoms from pressure on adjacent structures, distal embolism, acute thrombosis or rupture. In 88% of cases an aneurysm can be diagnosed by physical examination alone; confirmatory tests include soft-tissue roentgenography of the abdomen, ultrasonography, computer-assisted tomography and aortography. Repair is indicated for symptomatic or ruptured aortic aneurysms and for asymptomatic aneurysms over 5 cm in diameter. Early diagnosis and referral for repair is essential for optimum treatment of this common condition. PMID:7004617

  20. Heme Oxygenase-1 Expression Affects Murine Abdominal Aortic Aneurysm Progression.

    PubMed

    Azuma, Junya; Wong, Ronald J; Morisawa, Takeshi; Hsu, Mark; Maegdefessel, Lars; Zhao, Hui; Kalish, Flora; Kayama, Yosuke; Wallenstein, Matthew B; Deng, Alicia C; Spin, Joshua M; Stevenson, David K; Dalman, Ronald L; Tsao, Philip S

    2016-01-01

    Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is a cytoprotective enzyme upregulated in the vasculature by increased flow and inflammatory stimuli. Human genetic data suggest that a diminished HO-1 expression may predispose one to abdominal aortic aneurysm (AAA) development. In addition, heme is known to strongly induce HO-1 expression. Utilizing the porcine pancreatic elastase (PPE) model of AAA induction in HO-1 heterozygous (HO-1+/-, HO-1 Het) mice, we found that a deficiency in HO-1 leads to augmented AAA development. Peritoneal macrophages from HO-1+/- mice showed increased gene expression of pro-inflammatory cytokines, including MCP-1, TNF-alpha, IL-1-beta, and IL-6, but decreased expression of anti-inflammatory cytokines IL-10 and TGF-beta. Furthermore, treatment with heme returned AAA progression in HO-1 Het mice to a wild-type profile. Using a second murine AAA model (Ang II-ApoE-/-), we showed that low doses of the HMG-CoA reductase inhibitor rosuvastatin can induce HO-1 expression in aortic tissue and suppress AAA progression in the absence of lipid lowering. Our results support those studies that suggest that pleiotropic statin effects might be beneficial in AAA, possibly through the upregulation of HO-1. Specific targeted therapies designed to induce HO-1 could become an adjunctive therapeutic strategy for the prevention of AAA disease.

  1. Possible Dual Role of Decorin in Abdominal Aortic Aneurysm

    PubMed Central

    Ueda, Koshiro; Yoshimura, Koichi; Yamashita, Osamu; Harada, Takasuke; Morikage, Noriyasu; Hamano, Kimikazu

    2015-01-01

    Abdominal aortic aneurysm (AAA) is characterized by chronic inflammation, which leads to pathological remodeling of the extracellular matrix. Decorin, a small leucine-rich repeat proteoglycan, has been suggested to regulate inflammation and stabilize the extracellular matrix. Therefore, the present study investigated the role of decorin in the pathogenesis of AAA. Decorin was localized in the aortic adventitia under normal conditions in both mice and humans. AAA was induced in mice using CaCl2 treatment. Initially, decorin protein levels decreased, but as AAA progressed decorin levels increased in all layers. Local administration of exogenous decorin prevented the development of CaCl2-induced AAA. However, decorin was highly expressed in the degenerative lesions of human AAA walls, and this expression positively correlated with matrix metalloproteinase (MMP)-9 expression. In cell culture experiments, the addition of decorin inhibited secretion of MMP-9 in vascular smooth muscle cells, but had the opposite effect in macrophages. The results suggest that decorin plays a dual role in AAA. Adventitial decorin in normal aorta may protect against the development of AAA, but macrophages expressing decorin in AAA walls may facilitate the progression of AAA by up-regulating MMP-9 secretion. PMID:25781946

  2. Abdominal Pain in the Presence of Small Abdominal Aortic Aneurysms: If in Doubt, Cut It Out!

    PubMed

    Georgakarakos, Efstratios; Schoretsanitis, Nikolaos; Koufopoulos, Georgios; Paulou, Konstantinos; Lazarides, Miltos K

    2017-02-03

    Although small (<5 cm) abdominal aortic aneurysms (AAA) have been associated with symptoms and indication for intervention scarcely, the clinicians should never exclude such potential association especially in the absence of other overt pathological findings. In such cases, a surgical exploration with consequent intervention, if feasible, should be justified to prevent a detrimental evolution in a dubious scenario. In this article, we present 2 cases of patients with small AAA presenting with severe abdominal pain. In the absence of other solid clinical and radiological pathological findings, both patients underwent laparotomy where an inflammatory small AAA was identified and subjected either to resection and restoration with a tube graft or secondary endovascular repair because the periaortic fibrosis precluded the open repair. The characteristics and rationale of treatment modalities are exemplified and discussed.

  3. Inflammatory abdominal aortic aneurysms and atherosclerotic abdominal aortic aneurysms--comparisons of clinical features and long-term results.

    PubMed

    Sasaki, S; Yasuda, K; Takigami, K; Yamauchi, H; Shiiya, N; Sakuma, M

    1997-03-01

    A total of 274 patients with abdominal aortic aneurysms due to atherosclerosis (AAA) and 16 patients with inflammatory abdominal aortic aneurysms (IAAA) were reviewed to compare and contrast the clinical characteristics of the 2 groups. The AAA group comprised 243 men and 31 women with a mean age of 69.2 +/- 0.4 (range 51-86) years. The IAAA group comprised 15 men and 1 woman with a mean age of 67.4 +/- 2.0 (range 53-81) years. Most patients with IAAA (12/16; 75.0%) had pain at presentation, whereas only 37 out of 274 patients (13.5%) with AAA had pain (p < 0.001). Fifty out of 274 patients (18.2%) with AAA were asymptomatic, the most common principal complaint being a pulsatile tumor, which was found in 150 out of 274 patients (54.7%; p < 0.005 vs IAAA). Regarding laboratory findings of inflammation, preoperative erythrocyte sedimentation rate values were elevated in 15 out of 16 (93.8%) patients, and C-reactive protein values were elevated in 13 out of 16 (81.3%) patients with IAAA. The incidence of perioperative complications was similar in the 2 groups. The 30-day postoperative mortality among AAA patients was 6.2% (17/274 cases), including 12 cases of non-ruptured and 5 cases of ruptured AAA; in contrast, no early deaths occurred among patients with IAAA. The cumulative 5-year survival rate was 80.2% for IAAA patients and 74.6% for AAA patients (NS). The results of our review suggest that careful diagnosis and intra- and postoperative management could lead to patients with IAAA having a similar survival rate to those with AAA.

  4. Wegener's granulomatosis presenting as an abdominal aortic aneurysm: a case report

    PubMed Central

    2009-01-01

    Introduction Aortic aneurysm is not common in young patient. When a young patient presents with abdominal aortic aneurysm, there may be an underlying cause. Case presentation Here, we describe a case of a 33-year-old gentleman who presented with flu like illness, chest and abdominal pains following a tooth extraction. A chest X-ray and subsequent computerised tomogram of the chest and abdomen demonstrated lung nodules and an abdominal aortic aneurysm. The aneurysm was repaired and his serology was positive for Wegener's granulomatosis. A nasal mucosal biopsy confirmed WG. He was treated with oral steroids and cyclophosphamide. His graft leaked and had to be replaced with a synthetic graft. Two months after his re-operation, he remains well. Conclusion Whenever a young patient presents with an abdominal aortic aneurysm, an underlying connective disease should be excluded because early steroid/immunosuppressive treatment may prevent the development of further aneurysms. PMID:20066062

  5. Acute thrombosis of abdominal aortic aneurysm subsequent to Heimlich maneuver: a case report.

    PubMed

    Kirshner, R L; Green, R M

    1985-07-01

    We report a case of acute thrombosis of an abdominal aortic aneurysm secondary to a correctly applied and successful Heimlich maneuver. Although the Heimlich maneuver is generally safe and effective, this possible catastrophic consequence needs to be recognized.

  6. Abdominal compartment syndrome after endovascular repair for ruptured abdominal aortic aneurysm leads to acute intestinal necrosis

    PubMed Central

    Chen, Xiyang; Zhao, Jichun; Huang, Bin; Yuan, Ding; Yang, Yi; Ma, Yukui

    2016-01-01

    Abstract Introduction: Abdominal compartment syndrome (ACS) after endovascular repair (EVAR) of rupture abdominal aortic aneurysm (rAAA) is a rare emergency situation, which has a high mortality. However, the progression of ACS is rapid and the diagnosis is usually been delayed, which increase the difficulties in treatment and affect the prognosis. We describe a case of a sever complication (acute intestinal necrosis) resulting from ACS after endovascular repair of rAAA. Clinical Finding: An elderly man, 81 years old, complained a sudden lower abdominal and back pain without any predisposing cause. He had a history of hypertension for 20 years without any regular anti-hypertensive therapy. Physical Examination revealed that the blood pressure was 89/54 mmHg, pulse was 120/min, oxygen saturation was 91%. The abdominal ultrasound and the CTA (computed tomography angiography) scan revealed a rAAA. Emergency EVAR under general anesthesia was performed for this patient. Diagnosis: Fourteen hours after endovascular repair, sudden decreased of blood pressure (70/50 mmHg) and oxygen saturation (70%) was observed. ACS or bleeding of retroperitoneal space was diagnosed. Interventions: Abdominal laparotomy was immediately performed. ACS was verified and a severe complication (acute intestinal necrosis) was observed, intestinal resection was performed for this patient. Outcomes: Unfortunately, this patient died after operation because of multi-organ failure in a very short period, which is very rare regarding to this condition. Surgical pathology, diagnosis and management were discussed. Conclusion: ACS was occurred with a severe complication (acute intestinal necrosis) in a very short period, which is very rare regarding to this condition after EVAR, it reminds us the severe result of ACS and more methods to prevent it happened after surgical management. PMID:27893667

  7. ACR Appropriateness Criteria® pulsatile abdominal mass, suspected abdominal aortic aneurysm.

    PubMed

    Desjardins, Benoit; Dill, Karin E; Flamm, Scott D; Francois, Christopher J; Gerhard-Herman, Marie D; Kalva, Sanjeeva P; Mansour, M Ashraf; Mohler, Emile R; Oliva, Isabel B; Schenker, Matthew P; Weiss, Clifford; Rybicki, Frank J

    2013-01-01

    Clinical palpation of a pulsating abdominal mass alerts the clinician to the presence of a possible abdominal aortic aneurysm (AAA). Generally an arterial aneurysm is defined as a localized arterial dilatation ≥50% greater than the normal diameter. Imaging studies are important in diagnosing the cause of a pulsatile abdominal mass and, if an AAA is found, in determining its size and involvement of abdominal branches. Ultrasound (US) is the initial imaging modality of choice when a pulsatile abdominal mass is present. Noncontrast computed tomography (CT) may be substituted in patients for whom US is not suitable. When aneurysms have reached the size threshold for intervention or are clinically symptomatic, contrast-enhanced multidetector CT angiography (CTA) is the best diagnostic and preintervention planning study, accurately delineating the location, size, and extent of aneurysm and the involvement of branch vessels. Magnetic resonance angiography (MRA) may be substituted if CT cannot be performed. Catheter arteriography has some utility in patients with significant contraindications to both CTA and MRA. The American College of Radiology Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

  8. Lumbosacral radiculopathy secondary to abdominal aortic aneurysms. Report of three cases.

    PubMed

    Wilberger, J E

    1983-06-01

    Focal neurological deficits as the initial manifestation of expanding or ruptured abdominal aortic aneurysms are uncommon. When such a situation does occur, the femoral nerve is most often involved due to retroperitoneal or iliopsoas hematoma. Three cases of typical lumbosacral radiculopathy caused by an abdominal aortic aneurysm are reported to emphasize the importance of considering this diagnosis in the older patient with leg pain and radiculopathic findings.

  9. Modification of an endovascular stent graft for abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Moloye, Olajompo Busola

    Endovascular surgery is currently used to treat abdominal aortic aneurysms (AAA). A stent graft is deployed to exclude blood flow from the aneurysm sac. It is an effective procedure used in preventing aneurysm rupture, with reduced patient morbidity and mortality compared to open surgical repair. Migration and leakage around the device ("endoleak") due to poor sealing of the stent graft to the aorta have raised concerns about the long-term durability of endovascular repair. A preliminary study of cell migration and proliferation is presented as a prelude to a more extensive in vivo testing. A method to enhance the biological seal between the stent graft and the aorta is proposed to eliminate this problem. This can be achieved by impregnating the stent graft with 50/50 poly (DL-lactide co glycolic acid) (PLGA) and growth factors such as basic fibroblast growth factor (bFGF) or connective tissue growth factor (CTGF), at the proximal and distal ends. It is hypothesized that as PLGA degrades it will release the growth factors that will promote proliferation and migration of aortic smooth muscle cells to the coated site, leading to a natural seal between the aorta and the stent graft. In addition, growth factor release should promote smooth muscle cell (SMC) contraction that will help keep the stent graft in place at the proximal and distal ends. It is shown that a statistically significant effect of increased cell proliferation and migration is observed for CTGF release. Less of an effect is noted for bFGF or just the PLGA. The effect is estimated to be large enough to be clinically significant in a future animal study. The long term goal of this study is to reduce migration encounter after graft deployment and to reduce secondary interventions of EVAR especially for older patients who are unfit for open surgical treatment.

  10. Cyclic transition to turbulence in rigid abdominal aortic aneurysm models

    NASA Astrophysics Data System (ADS)

    Yip, T. H.; Yu, S. C. M.

    2001-08-01

    The hydrodynamic stability of cyclic flows inside rigid abdominal aortic aneurysm (AAA) models was investigated. Rectified sine waveforms were used to simulate aortic flow conditions (Re mean=1600-2100 and α=7.2-12.2). Depending on the bulge geometry ( D/ d and L/ d ratios), AAA flows can be broadly classified into three regimes, namely types A, B and C, respectively. While type A has no vortex formation, type B and C have distinctive laminar vortical structures that are very different from one another. The type of flow regimes would also determine where and when the transition to turbulence would occur and the portion of the cycle at which the flow remains turbulent in the bulge. The stability characteristics of types B and C are obtained from the linear stability analysis performed on the unsteady velocity profiles measured at different phases of a cycle. Based on the linear stability analyses, instability is found to initiate in the bulge for types B and C through the formation of vortical structures. Instability grows progressively during the acceleration phase and transition to turbulence in the bulge occurs shortly after the commencement of the deceleration phase in all cases investigated. The mechanisms of transition to turbulence for types B and C are discussed. Although transition to turbulence appears in all the cases investigated here, fully laminar flows in types B and C are predicted to exist by the linear stability theory under extreme flow conditions. Finally, the in vivo biological implications of the in vitro results were discussed.

  11. Epithelioid Angiosarcoma With Metastatic Disease After Endovascular Therapy of Abdominal Aortic Aneurysm

    SciTech Connect

    Schmehl, Joerg; Scharpf, Marcus; Brechtel, Klaus; Kalender, Guenay; Heller, Stephan; Claussen, Claus D.; Lescan, Mario

    2012-02-15

    Malignancies of the aortic wall represent a rare condition, and only a few reports have covered cases of sarcomas arising at the site of a prosthesis made of Dacron. A coincidence with endovascular repair has only been reported in one case to date. We report a patient with epithelioid angiosarcoma and metastatic disease, which was found in an aneurysmal sac after endovascular aortic repair for abdominal aortic aneurysm.

  12. NOX isoforms in the development of abdominal aortic aneurysm.

    PubMed

    Siu, Kin Lung; Li, Qiang; Zhang, Yixuan; Guo, Jun; Youn, Ji Youn; Du, Jie; Cai, Hua

    2017-04-01

    Oxidative stress plays an important role in the formation of abdominal aortic aneurysm (AAA), and we have recently established a causal role of uncoupled eNOS in this severe human disease. We have also shown that activation of NADPH oxidase (NOX) lies upstream of uncoupled eNOS. Therefore, identification of the specific NOX isoforms that are required for eNOS uncoupling and AAA formation would ultimately lead to novel therapies for AAA. In the present study, we used the Ang II infused hph-1 mice to examine the roles of NOX isoforms in the development of AAA. We generated double mutants of hph-1-NOX1, hph-1-NOX2, hph-1-p47phox, and hph-1-NOX4. After two weeks of Ang II infusion, the incidence rate of AAA substantially dropped from 76.5% in Ang II infused hph-1 mice (n=34) to 11.1%, 15.0%, 9.5% and 0% in hph-1-NOX1 (n=27), hph-1-NOX2 (n=40), hph-1-p47phox (n=21), and hph-1-NOX4 (n=33) double mutant mice, respectively. The size of abdominal aortas of the four double mutant mice, determined by ultrasound analyses, was significantly smaller than the hph-1 mice. Aortic nitric oxide and H4B bioavailabilities were markedly improved in the double mutants, while superoxide production and eNOS uncoupling activity were substantially diminished. These effects seemed attributed to an endothelial specific restoration of dihydrofolate reductase expression and activity, deficiency of which has been shown to induce eNOS uncoupling and AAA formation in both Ang II-infused hph-1 and apoE null animals. In addition, over-expression of human NOX4 N129S or T555S mutant newly identified in aneurysm patients increased hydrogen peroxide production, further implicating a relationship between NOX and human aneurysm. Taken together, these data indicate that NOX isoforms 1, 2 or 4 lies upstream of dihydrofolate reductase deficiency and eNOS uncoupling to induce AAA formation. These findings may promote development of novel therapeutics for the treatment of the disease by inhibiting NOX signaling.

  13. Endovascular Exclusion of Abdominal Aortic Aneurysms: Initial Experience with Stent-Grafts in Cardiology Practice

    PubMed Central

    Howell, Marcus H.; Zaqqa, Munir; Villareal, Rollo P.; Strickman, Neil E.; Krajcer, Zvonimir

    2000-01-01

    The use of an endovascular stent-graft prosthesis for the treatment of infrarenal abdominal aortic aneurysms is receiving increasing attention as an option that may avoid the significant morbidity and mortality associated with open surgical treatment. We studied the clinical effectiveness of stent-grafts in patients with infrarenal abdominal aortic aneurysms. Between October 1995 and May 1998, 33 patients underwent infrarenal abdominal aortic aneurysm exclusion with a homemade polytetrafluoroethylene-covered stent, and between November 1998 and September 1999, 56 patients underwent abdominal aortic aneurysm exclusion with the Medtronic AneuRx stent-graft. Overall, these patients represented a high-risk surgical group. The technical success rate was 100% in both groups. No patient required immediate conversion to open repair. With the polytetrafluoroethy-lene-covered stent, the primary success rate was 33%, and the secondary success rate was 76%. In the AneuRx group, the primary success rate was 82.8%, and the secondary success rate was 85.3% at 6 months. There was no procedural or 1-month mortality or major morbidity in either group. By showing that infrarenal abdominal aortic aneurysms can be treated safely and successfully with an endoluminal stent-graft, our early results provide additional support for the endovascular treatment of abdominal aortic aneurysms. Further follow-up studies will determine the long-term ability of such treatment to prevent aneurysmal rupture and death. PMID:10928501

  14. [Inflammatory aortic aneurysms: Single center experiences with endovascular repair of inflammatory abdominal aortic aneurysms].

    PubMed

    Strube, H; Treitl, M; Reiser, M; Steckmeier, B; Sadeghi-Azandaryani, M

    2010-10-01

    We report our single center experience of renal function, hydronephrosis and changes in perianeurysmal fibrosis (PAF) after endovascular repair (EVAR) of inflammatory abdominal aortic aneurysms (IAAA). A total of 6 patients were treated for IAAA with EVAR and the technical success was 100%. During the follow-up period 5 patients showed regression of PAF and 1 patient showed minor progression of PAF on computed tomography scans. In 2 patients hydronephrosis was regressive postoperatively but no patients died within 30 days. There were no secondary complications to report and no secondary intervention was necessary. In the long-term course one patient exhibited complete regression of PAF.In appropriate cases EVAR is a safe method for aneurysm repair for IAAA. In patients with acute inflammation or hydronephrosis individual treatment concepts are required.

  15. The effect of aortic morphology on peri-operative mortality of ruptured abdominal aortic aneurysm

    PubMed Central

    2015-01-01

    Aims To investigate whether aneurysm shape and extent, which indicate whether a patient with ruptured abdominal aortic aneurysm (rAAA) is eligible for endovascular repair (EVAR), influence the outcome of both EVAR and open surgical repair. Methods and results The influence of six morphological parameters (maximum aortic diameter, aneurysm neck diameter, length and conicality, proximal neck angle, and maximum common iliac diameter) on mortality and reinterventions within 30 days was investigated in rAAA patients randomized before morphological assessment in the Immediate Management of the Patient with Rupture: Open Versus Endovascular strategies (IMPROVE) trial. Patients with a proven diagnosis of rAAA, who underwent repair and had their admission computerized tomography scan submitted to the core laboratory, were included. Among 458 patients (364 men, mean age 76 years), who had either EVAR (n = 177) or open repair (n = 281) started, there were 155 deaths and 88 re-interventions within 30 days of randomization analysed according to a pre-specified plan. The mean maximum aortic diameter was 8.6 cm. There were no substantial correlations between the six morphological variables. Aneurysm neck length was shorter in those undergoing open repair (vs. EVAR). Aneurysm neck length (mean 23.3, SD 16.1 mm) was inversely associated with mortality for open repair and overall: adjusted OR 0.72 (95% CI 0.57, 0.92) for each 16 mm (SD) increase in length. There were no convincing associations of morphological parameters with reinterventions. Conclusion Short aneurysm necks adversely influence mortality after open repair of rAAA and preclude conventional EVAR. This may help explain why observational studies, but not randomized trials, have shown an early survival benefit for EVAR. Clinical trial registration: ISRCTN 48334791. PMID:25627357

  16. The application of metabolic profiling to abdominal aortic aneurysm research.

    PubMed

    Qureshi, Mahim Irfan; Greco, Michele; Vorkas, Panagiotis Andrea; Holmes, Elaine; Davies, Alun H

    2017-03-13

    Rationale Abdominal aortic aneurysm (AAA) is a complex disease posing diagnostic and therapeutic challenges. Metabonomics may aid in the diagnosis of AAA, determination of individualised risk, discovery of therapeutic targets, and improve understanding of pathogenesis. Objective To review the diversity and outcomes of existing AAA metabonomic research. Methods and Results A systematic review has been performed. Original research studies applying metabonomics to human aneurysmal disease were included. Seven relevant articles were identified: four studies were based on plasma/serum metabolite profiling, and three studies examined aneurysmal tissue. Aminomalonic acid, guanidinosuccinic acid and glycerol emerge as potential plasma biomarkers of large aneurysm. Lipid profiling improves predictive models of aneurysm presence. Patterns of metabolite variation associated with AAA relate to carbohydrate and lipid metabolism. Perioperative perturbations in metabolites suggest differential systemic inflammatory responses to surgery, generating hypotheses for adjunctive perioperative therapy. Significant limitations include small study sizes, lack of correction for multiple testing false discovery rates, and single time-point sampling. Conclusion Metabolic profiling carries the potential to identify biomarkers of AAA and elucidate pathways underlying aneurysmal disease. Statistically and methodologically robust studies are required for validation, addressing the hiatus in understanding mechanisms of aneurysm growth and developing effective treatment strategies.

  17. Arteriomegaly and inflammatory abdominal aortic aneurysm. Case report.

    PubMed

    Cavallini, M; Uccini, S; Luzi, G; Murante, G; Tagliacozzo, S

    1997-02-01

    In this case report inflammatory abdominal aortic aneurysm (IAAA) was superimposed on an arteriomegaly condition complicated by bilateral aneurysm of the common iliac arteries. Obstruction of the right ureter, mild hydronephrosis of the left system and a slight impairment of renal function were also present. Preoperative cellular and humoral immunological parameters were within normal limits while the erythrocyte sedimentation rate (ESR) was elevated (74 mm). Histological analysis showed numerous scattered lymphoid cells or organized in follicles with germinal centers within the adventitial thickening of the IAAA wall. Immunohistochemical analysis on frozen sections demonstrated that dispersed and perivascular lymphoid cells were mainly composed of similar amounts of CD3+/CD4+ and CD3+/CD8+ T lymphocytes. Histological analysis of the common iliac artery aneurysm showed a mild intimal thickening will small aggregates of macrophages. After aneurysm repair all peripheral blood analysis normalized within one month after surgery. The IAAA observed in our patient with arteriomegaly as underlying arterial disease cannot be interpreted as an inflammatory variation of an atherosclerotic aneurysm. The histological pattern of the inflammatory reaction and its resolution after surgery give, in our opinion, more credit to the etiopathogenetic hypothesis of a reaction elicited by an antigen within the arterial wall of the infrarenal aorta which might be enhanced by the lymphatic stasis subsequent to aneurysm compression.

  18. Contemporary Applications of Ultrasound in Abdominal Aortic Aneurysm Management

    PubMed Central

    Scaife, Mark; Giannakopoulos, Triantafillos; Al-Khoury, Georges E.; Chaer, Rabih A.; Avgerinos, Efthymios D.

    2016-01-01

    Ultrasound (US) is a well-established screening tool for detection of abdominal aortic aneurysms (AAAs) and is currently recommended not only for those with a relevant family history but also for all men and high-risk women older than 65 years of age. The advent of minimally invasive endovascular techniques in the treatment of AAAs [endovascular aneurysm repair (EVAR)] has increased the need for repeat imaging, especially in the postoperative period. Nevertheless, preoperative planning, intraoperative execution, and postoperative surveillance all mandate accurate imaging. While computed tomographic angiography and angiography have dominated the field, repeatedly exposing patients to the deleterious effects of cumulative radiation and intravenous nephrotoxic contrast, US technology has significantly evolved over the past decade. In addition to standard color duplex US, 2D, 3D, or 4D contrast-enhanced US modalities are revolutionizing AAA management and postoperative surveillance. This technology can accurately measure AAA diameter and volume, and most importantly, it can detect endoleaks post-EVAR with high sensitivity and specificity. 4D contrast-enhanced US can even provide hemodynamic information about the branch vessels following fenestrated EVARs. The need for experienced US operators and accredited vascular labs is mandatory to guarantee the reliability of the results. This review article presents a comprehensive overview of the literature on the state-of-art US imaging in AAA management, including post-EVAR follow-up, techniques, and diagnostic accuracy. PMID:27303669

  19. Contemporary Applications of Ultrasound in Abdominal Aortic Aneurysm Management.

    PubMed

    Scaife, Mark; Giannakopoulos, Triantafillos; Al-Khoury, Georges E; Chaer, Rabih A; Avgerinos, Efthymios D

    2016-01-01

    Ultrasound (US) is a well-established screening tool for detection of abdominal aortic aneurysms (AAAs) and is currently recommended not only for those with a relevant family history but also for all men and high-risk women older than 65 years of age. The advent of minimally invasive endovascular techniques in the treatment of AAAs [endovascular aneurysm repair (EVAR)] has increased the need for repeat imaging, especially in the postoperative period. Nevertheless, preoperative planning, intraoperative execution, and postoperative surveillance all mandate accurate imaging. While computed tomographic angiography and angiography have dominated the field, repeatedly exposing patients to the deleterious effects of cumulative radiation and intravenous nephrotoxic contrast, US technology has significantly evolved over the past decade. In addition to standard color duplex US, 2D, 3D, or 4D contrast-enhanced US modalities are revolutionizing AAA management and postoperative surveillance. This technology can accurately measure AAA diameter and volume, and most importantly, it can detect endoleaks post-EVAR with high sensitivity and specificity. 4D contrast-enhanced US can even provide hemodynamic information about the branch vessels following fenestrated EVARs. The need for experienced US operators and accredited vascular labs is mandatory to guarantee the reliability of the results. This review article presents a comprehensive overview of the literature on the state-of-art US imaging in AAA management, including post-EVAR follow-up, techniques, and diagnostic accuracy.

  20. The effect of flow recirculation on abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Taib, Ishkrizat; Amirnordin, Shahrin Hisham; Madon, Rais Hanizam; Mustafa, Norrizal; Osman, Kahar

    2012-06-01

    The presences of flow recirculation at the abdominal aortic aneurysm (AAA) region yield the unpredictable failure of aneurismal wall. The failure of the aneurismal wall is closely related to the hemodynamic factor. Hemodynamic factor such as pressure and velocity distribution play a significance role of aneurysm growth and rupture. By using the computational approach, the influence of hemodynamic factor is investigated using computational fluid dynamic (CFD) method on the virtual AAA model. The virtual 3D AAAs model was reconstructed from Spiral Computed Tomography scan (CT-scan). The blood flow is assumed as being transient, laminar and Newtonian within a rigid section of the vessel. The blood flow also driven by an imposed of pressure gradient in the form of physiological waveform. The pulsating blood flow is also considered in this simulation. The results on pressure distribution and velocity profile are analyzed to interpret the behaviour of flow recirculation. The results show the forming of vortices is seen at the aneurysm bulge. This vortices is form at the aneurysm region then destroyed rapidly by flow recirculation. Flow recirculation is point out much higher at distal end of aneurysm closed to iliac bifurcation. This phenomenon is managed to increase the possibility of aneurysm growth and rupture.

  1. Distribution of Wall Stress in Abdominal Aortic Aneurysm (AAA)

    NASA Astrophysics Data System (ADS)

    Lasheras, Juan

    2005-11-01

    Abdominal aortic aneurysm (AAA) rupture is believed to occur when the mechanical stress acting on the wall exceeds the strength of the wall tissue. Therefore, knowledge of the AAA wall stress distribution could be useful in assessing its risk of rupture. In our research, a finite element analysis was used to determine the wall stresses both in idealized models and in a real clinical model in which the aorta was considered isotropic with nonlinear material properties and was loaded with a given pressure. In the idealized models, both maximum diameter and asymmetry were found to have substantial influence on the distribution of the wall stress. The thrombus inside the AAA was also found to help protecting the walls from high stresses. Using CT scans of the AAA, the actual geometry of the aneurysm was reconstructed and we found that wall tension increases on the flatter surface (typically corresponds to the posterior surface) and at the inflection points of the bulge. In addition to the static analysis, we also performed simulations of the effect of unsteady pressure wave propagation inside the aneurysm.

  2. The biaxial biomechanical behavior of abdominal aortic aneurysm tissue.

    PubMed

    O'Leary, Siobhan A; Healey, Donagh A; Kavanagh, Eamon G; Walsh, Michael T; McGloughlin, Tim M; Doyle, Barry J

    2014-12-01

    Rupture of the abdominal aortic aneurysm (AAA) occurs when the local wall stress exceeds the local wall strength. Knowledge of AAA wall mechanics plays a fundamental role in the development and advancement of AAA rupture risk assessment tools. Therefore, the aim of this study is to evaluate the biaxial mechanical properties of AAA tissue. Multiple biaxial test protocols were performed on AAA samples harvested from 28 patients undergoing open surgical repair. Both the Tangential Modulus (TM) and stretch ratio (λ) were recorded and compared in both the circumferential (ϴ) and longitudinal (L) directions at physiologically relevant stress levels, the influence of patient specific factors such as sex, age AAA diameter and status were examined. The biomechanical response was also fit to a hyperplastic material model. The AAA tissue was found to be anisotropic with a greater tendency to stiffen in the circumferential direction compared to the longitudinal direction. An anisotropic hyperelastic constitutive model represented the data well and the properties were not influenced by the investigated patient specific factors however, a future study utilizing a larger cohort of patients is warranted to confirm these findings. This work provides further insights on the biomechanical behavior of AAA and may be useful in the development of more reliable rupture risk assessment tools.

  3. Lipoprotein(a) Levels in Patients With Abdominal Aortic Aneurysm.

    PubMed

    Kotani, Kazuhiko; Sahebkar, Amirhossein; Serban, Maria-Corina; Ursoniu, Sorin; Mikhailidis, Dimitri P; Mariscalco, Giovanni; Jones, Steven R; Martin, Seth; Blaha, Michael J; Toth, Peter P; Rizzo, Manfredi; Kostner, Karam; Rysz, Jacek; Banach, Maciej

    2017-02-01

    Circulating markers relevant to the development of abdominal aortic aneurysm (AAA) are currently required. Lipoprotein(a), Lp(a), is considered a candidate marker associated with the presence of AAA. The present meta-analysis aimed to evaluate the association between circulating Lp(a) levels and the presence of AAA. The PubMed-based search was conducted up to April 30, 2015, to identify the studies focusing on Lp(a) levels in patients with AAA and controls. Quantitative data synthesis was performed using a random effects model, with standardized mean difference (SMD) and 95% confidence interval (CI) as summary statistics. Overall, 9 studies were identified. After a combined analysis, patients with AAA were found to have a significantly higher level of Lp(a) compared to the controls (SMD: 0.87, 95% CI: 0.41-1.33, P < .001). This result remained robust in the sensitivity analysis, and its significance was not influenced after omitting each of the included studies from the meta-analysis. The present meta-analysis confirmed a higher level of circulating Lp(a) in patients with AAA compared to controls. High Lp(a) levels can be associated with the presence of AAA, and Lp(a) may be a marker in screening for AAA. Further studies are needed to establish the clinical utility of measuring Lp(a) in the prevention and management of AAA.

  4. Rare Complication of non-Treated Abdominal Aortic Aneurysm: Extensive Thrombus in Right Cardiac Chambers

    PubMed Central

    Hotta, Viviane Tiemi; Bluemke, David A.; Staszko, Kamila Fernanda; Pereira, Ana Neri Rodrigues Epitacio; Rochitte, Carlos Eduardo

    2016-01-01

    A 78-year-old patient presented with shortness of breath after falling down. Transthoracic echocardiogram showed an extensive thrombus in the right atrium (RA), extensive thrombosis of the inferior vena cava (IVC), and abdominal aortic aneurysm (AAA). A magnetic resonance confirmed the thrombosis of the RA extending to the IVC, which was apparently fused to the abdominal aortic aneurysm (compression? erosion?). This case illustrates a severe and rare complication of a non-treated AAA. There probably was IVC erosion by the aortic aneurysm, leading to blood stasis and extensive thrombosis of the IVC and right cardiac chambers. PMID:27849260

  5. Clear Depiction of Inflammatory Abdominal Aortic Aneurysm with Diffusion-Weighted Magnetic Resonance Imaging

    SciTech Connect

    Orta Kilickesmez, Kadriye; Kilickesmez, Ozgur

    2010-04-15

    We report the case of an inflammatory abdominal aortic aneurysm incidentally detected clearly with diffusion-weighted magnetic resonance imaging (DW-MRI) during the examination of a patient with myelofibrosis with myeloid metaplasia that later converted to acute myeloid leukemia. DW-MRI revealed a hyperintense halo surrounding the abdominal aorta with aneurysmatic dilatation, establishing the diagnosis.

  6. Comparison of magnetic resonance imaging and ultrasonography in the evaluation of abdominal aortic aneurysms.

    PubMed

    Amparo, E G; Hoddick, W K; Hricak, H; Sollitto, R; Justich, E; Filly, R A; Higgins, C B

    1985-02-01

    Magnetic resonance imaging (MRI) was used to evaluate abdominal aortic aneurysms in 27 patients. The findings were compared retrospectively with CT, ultrasound (US), and angiography in 17 cases and prospectively with US in 10 cases. MRI identified the renal arteries in all cases, demonstrated involvement at or above the origin of the renal arteries in eight patients, and showed extension of the aneurysm into the iliac arteries in 12 cases. The outer dimension of the aneurysm, the diameter of the residual lumen, and the length of the aneurysm were measured easily from the MR images. The measurements of transverse dimension of the abdominal aortic aneurysm were similar for MRI, CT, and US. MRI more accurately defined extension above the renal arteries and below the aortic bifurcation. It is concluded that MRI provides the necessary information for the surveillance and preoperative evaluation of abdominal aortic aneurysms.

  7. The association of simple renal cysts with abdominal aortic aneurysms and their impact on renal function after endovascular aneurysm repair.

    PubMed

    Spanos, Konstantinos; Rountas, Christos; Saleptsis, Vasileios; Athanasoulas, Athanasios; Fezoulidis, Ioannis; Giannoukas, Athanasios D

    2016-04-01

    We validated the association of simple renal cysts with abdominal aortic aneurysm and other cardiovascular factors and assessed simple renal cysts' impact on renal function before and after endovascular abdominal aortic aneurysm repair. A retrospective analysis of prospectively collected data was conducted. Computed tomography angiograms of 100 consecutive male patients with abdominal aortic aneurysm who underwent endovascular abdominal aortic aneurysm repair (Group 1) were reviewed and compared with 100 computed tomography angiogram of aged-matched male patients without abdominal aortic aneurysm (Group 2). Patients' demographic data, risk factors, abdominal aortic aneurysm diameter, the presence of simple renal cyst and laboratory tests were recorded. No difference was observed between the two groups in respect to other cardiovascular risk factors except hyperlipidemia with higher prevalence in Group 1 (p < 0.05). Presence of simple renal cysts was independently associated with age (p < 0.05) and abdominal aortic aneurysm (p = 0.0157). There was no correlation between simple renal cysts and abdominal aortic aneurysm size or pre-operative creatinine and urea levels. No difference was observed in post-operative creatinine and urea levels either immediately after endovascular abdominal aortic aneurysm repair or in 12-month follow-up. In male patients, the presence of simple renal cysts is associated with abdominal aortic aneurysm and is increasing with age. However, their presence is neither associated with impaired renal function pre-endovascular abdominal aortic aneurysm repair and post-endovascular abdominal aortic aneurysm repair nor after 12-month follow-up.

  8. Staged endourologic and endovascular repair of an infrarenal inflammatory abdominal aortic aneurysm presenting with forniceal rupture.

    PubMed

    Edmonds, Rebecca D; Tomaszewski, Jeffrey J; Jackman, Stephen V; Chaer, Rabih A

    2008-11-01

    We present the case of a 79-year-old female who presented with severe left flank pain and a pulsatile abdominal mass. She was diagnosed with left peripelvic urinary extravasation and forniceal rupture secondary to an intact infrarenal inflammatory abdominal aortic aneurysm with extensive periaortic fibrosis. Successful operative repair was performed with staged ureteral and endovascular stenting with subsequent resolution of periaortic inflammation and ureteral obstruction, and shrinkage of the aneurysm sac. Inflammatory abdominal aortic aneurysms (IAAAs) represent 5% to 10% of all abdominal aortic aneurysms. The distinguishing features of inflammatory aneurysms include thickening of aneurysm wall, retroperitoneal fibrosis, and adhesions to adjacent retroperitoneal structures. The most commonly involved adjacent structures are the duodenum, left renal vein, and ureter. Adhesions to the urinary system can cause hydronephrosis or hydroureter and result in obstructive uropathy. An unusual case of IAAA presenting with forniceal rupture is presented, with successful endovascular and endourologic repair.

  9. Aortic transection and diverting bypass as treatment of repetitive recurrent abdominal aortic false aneurysm rupture in a patient with Behcet's disease.

    PubMed

    Kim, Sang-Dong; Won, Yong-Sung; Yun, Sang-Seob; Park, Sun-Cheol; Kim, Ji-Il; Moon, In-Sung; Koh, Yong-Bok

    2011-02-01

    Abdominal aortic false aneurysms in patients with Behcet's disease have been reported frequently and repaired successfully by various procedures; however, anastomotic false aneurysms have often been reported to occur after the operation. In this article, we report a case of four-time repetitive, recurrent suprarenal abdominal aortic false aneurysm ruptures that lasted for 7 years. The location of this aneurysm was not easy to repair not only by open surgical procedures but by endovascular stent because the aortic defect was too close to the visceral arterial branches. The last operation consisted of primary repair of aortic defect, transection of abdominal aorta at the level of supraceliac aorta with end closure, and a thoracic aorta to abdominal aorta bypass with Dacron graft. An 8-year follow-up revealed no more abdominal aortic aneurysm recurrence.

  10. Imaging of abdominal aortic aneurysm: the present and the future

    PubMed Central

    Hong, Hao; Yang, Yunan; Liu, Bo; Cai, Weibo

    2010-01-01

    Abdominal Aortic Aneurysm (AAA) is a common, progressive, and potentially lethal vascular disease. A major obstacle in AAA research, as well as patient care, is the lack of technology that enables non-invasive acquisition of molecular/cellular information in the developing AAA. In this review we will briefly summarize the current techniques (e.g. ultrasound, computed tomography, and magnetic resonance imaging) for anatomical imaging of AAA. We also discuss the various functional imaging techniques that have been explored for AAA imaging. In many cases, these anatomical and functional imaging techniques are not sufficient for providing surgeons/clinicians enough information about each individual AAA (e.g. rupture risk) to optimize patient management. Recently, molecular imaging techniques (e.g. optical and radionuclide-based) have been employed to visualize the molecular alterations associated with AAA, which are discussed in this review. Lastly, we try to provide a glance into the future and point out the challenges for AAA imaging. We believe that the future of AAA imaging lies in the combination of anatomical and molecular imaging techniques, which are largely complementary rather than competitive. Ultimately, with the right molecular imaging probe, clinicians will be able to monitor AAA growth and evaluate the risk of rupture accurately, so that the life-saving surgery can be provided to the right patients at the right time. Equally important, the right imaging probe will also allow scientists/clinicians to acquire critical data during AAA development and to more accurately evaluate the efficacy of potential treatments. PMID:20180767

  11. Imaging of Abdominal Aortic Aneurysm: the present and the future.

    PubMed

    Hong, Hao; Yang, Yunan; Liu, Bo; Cai, Weibo

    2010-11-01

    Abdominal Aortic Aneurysm (AAA) is a common, progressive, and potentially lethal vascular disease. A major obstacle in AAA research, as well as patient care, is the lack of technology that enables non-invasive acquisition of molecular/cellular information in the developing AAA. In this review we will briefly summarize the current techniques (e.g. ultrasound, computed tomography, and magnetic resonance imaging) for anatomical imaging of AAA. We also discuss the various functional imaging techniques that have been explored for AAA imaging. In many cases, these anatomical and functional imaging techniques are not sufficient for providing surgeons/clinicians enough information about each individual AAA (e.g. rupture risk) to optimize patient management. Recently, molecular imaging techniques (e.g. optical and radionuclide-based) have been employed to visualize the molecular alterations associated with AAA, which are discussed in this review. Lastly, we try to provide a glance into the future and point out the challenges for AAA imaging. We believe that the future of AAA imaging lies in the combination of anatomical and molecular imaging techniques, which are largely complementary rather than competitive. Ultimately, with the right molecular imaging probe, clinicians will be able to monitor AAA growth and evaluate the risk of rupture accurately, so that the life-saving surgery can be provided to the right patients at the right time. Equally important, the right imaging probe will also allow scientists/clinicians to acquire critical data during AAA development and to more accurately evaluate the efficacy of potential treatments.

  12. Interleukin-6 receptor pathways in abdominal aortic aneurysm

    PubMed Central

    Harrison, Seamus C.; Smith, Andrew J.P.; Jones, Gregory T.; Swerdlow, Daniel I.; Rampuri, Riaz; Bown, Matthew J.; Folkersen, Lasse; Baas, Annette F.; de Borst, Gert Jan; Blankensteijn, Jan D.; Price, Jacqueline F.; van der Graaf, Yolanda; McLachlan, Stela; Agu, Obi; Hofman, Albert; Uitterlinden, Andre G.; Franco-Cereceda, Anders; Ruigrok, Ynte M.; van't Hof, F.N.; Powell, Janet T.; van Rij, Andre M.; Casas, Juan P.; Eriksson, Per; Holmes, Michael V.; Asselbergs, Folkert W.; Hingorani, Aroon D.; Humphries, Steve E.

    2013-01-01

    Methods We conducted a systematic review and meta-analysis of studies reporting circulating IL-6 in AAA, and new investigations of the association between a common non-synonymous functional variant (Asp358Ala) in the IL-6R gene (IL6R) and AAA, followed the analysis of the variant both in vitro and in vivo. Inflammation may play a role in the development of abdominal aortic aneurysms (AAA). Interleukin-6 (IL-6) signalling through its receptor (IL-6R) is one pathway that could be exploited pharmacologically. We investigated this using a Mendelian randomization approach. Results Up to October 2011, we identified seven studies (869 cases, 851 controls). Meta-analysis demonstrated that AAA cases had higher levels of IL-6 than controls [standardized mean difference (SMD) = 0.46 SD, 95% CI = 0.25–0.66, I2 = 70%, P = 1.1 × 10–5 random effects]. Meta-analysis of five studies (4524 cases/15 710 controls) demonstrated that rs7529229 (which tags the non-synonymous variant Asp358Ala, rs2228145) was associated with a lower risk of AAA, per Ala358 allele odds ratio 0.84, 95% CI: 0.80–0.89, I2 = 0%, P = 2.7 × 10–11). In vitro analyses in lymphoblastoid cell lines demonstrated a reduction in the expression of downstream targets (STAT3, MYC and ICAM1) in response to IL-6 stimulation in Ala358 carriers. Conclusions A Mendelian randomization approach provides robust evidence that signalling via the IL-6R is likely to be a causal pathway in AAA. Drugs that inhibit IL-6R may play a role in AAA management. PMID:23111417

  13. Abdominal aortic calcification: A reappraisal of epidemiological and pathophysiological data.

    PubMed

    Szulc, Pawel

    2016-03-01

    In men and women, there is a significant association between the risk of cardiovascular event (myocardial infarction, stroke) and risk of major fragility fracture (hip, vertebra). Abdominal aortic calcification (AAC) can be assessed using semiquantitative scores on spine radiographs and spine scans obtained by DXA. Severe AAC is associated with higher risk of major cardiovascular event. Not only does severe AAC reflect poor cardiovascular health status, but also directly disturbs blood flow in the vascular system. Severe (but not mild or moderate) AAC is associated with lower bone mineral density (BMD), faster bone loss and higher risk of major fragility fracture. The fracture risk remains increased after adjustment for BMD and other potential risk factors. The association between severe AAC and fracture risk was found in both sexes, mainly in the follow-ups of less than 10years. Many factors contribute to initiation and progression of AAC: lifestyle, co-morbidities, inorganic ions, dyslipidemia, hormones, cytokines (e.g. inflammatory cytokines, RANKL), matrix vesicles, microRNAs, structural proteins (e.g. elastin), vitamin K-dependent proteins, and medications (e.g. vitamin K antagonists). Osteogenic transdifferentiation of vascular smooth muscle cells (VSMC) and circulating osteoprogenitors penetrating into vascular wall plays a major role in the AAC initiation and progression. Vitamin K-dependent proteins protect vascular tunica media against formation of calcified deposits (matrix GLA protein, GLA-rich protein) and against VSMC apoptosis (Gas6). Further studies are needed to investigate clinical utility of AAC for the assessment of fracture and cardiovascular risk at the individual level and develop new medications permitting to prevent AAC progression.

  14. Emergency Endovascular Treatment of Abdominal Aortic Aneurysms: Feasibility and Results

    SciTech Connect

    Lagana, Domenico Carrafiello, Gianpaolo; Mangini, Monica; Fontana, Federico; Caronno, Roberto; Castelli, Patrizio; Cuffari, Salvatore; Fugazzola, Carlo

    2006-04-15

    Purpose. To assess the feasibility and effectiveness of emergency endovascular treatment of abdominal aortic aneurysms (AAAs). Methods. During 36 months we treated, on an emergency basis, 30 AAAs with endovascular exclusion. In 21 hemodynamically stable patients preoperative CT angiography (CTA) was performed to confirm the diagnosis and to plan the treatment; 9 patients with hemorrhagic shock were evaluated with angiography performed in the operating room. Twenty-two Excluder (Gore) and 8 Zenith (Cook) stent-grafts (25 bifurcated and 5 aorto-uni-iliac) were used. The follow-up was performed by CTA at 1, 3, 6, and 12 months. Results. Technical success was achieved in 100% of cases with a 10% mortality rate. The total complication rate was 23% (5 increases in serum creatinine level and 2 wound infections). During the follow-up, performed in 27 patients (1-36 months, mean 15.2 months), 4 secondary endoleaks (15%) (3 type II, 2 spontaneously thrombosed and 1 under observation, and 1 type III treated by iliac extender insertion) and 1 iliac leg occlusion (treated with femoro-femoral bypass) occurred. We observed a shrinkage of the aneurysmal sac in 8 of 27 cases and stability in 19 of 27 cases; we did not observe any endotension. Conclusions. Endovascular repair is a good option for emergency treatment of AAAs. The team's experience allows correct planning of the procedure in emergency situations also, with technical results comparable with elective repair. In our experience the bifurcated stent-graft is the device of choice in patients with suitable anatomy because the procedure is less time-consuming than aorto-uni-iliac stent-grafting with surgical crossover, allowing faster aneurysm exclusion. However, further studies are required to demonstrate the long-term efficacy of endovascular repair compared with surgical treatment.

  15. A Combination of Thoracic and Abdominal Stent-Grafts to Treat An Abdominal Aortic Aneurysm with Hostile Proximal Neck.

    PubMed

    Massara, Mafalda; Prunella, Roberto; Gerardi, Pasquale; De Caridi, Giovanni; Serra, Raffaele; Notarstefano, Stefano; Impedovo, Giovanni

    2017-02-01

    Endovascular aneurysm repair (EVAR) actually represents the treatment of choice for most patients affected by abdominal aortic aneurysm (AAA). However, the feasibility of EVAR depends on anatomical characteristics of abdominal aorta and iliofemoral axis. We present the case of an 82-year-old man affected by severe left hydronephrosis, kidney tumor, and ureteral tumor requiring nephrectomy, who also presented a very voluminous AAA with a large diameter (96 mm), and a large proximal neck (39 mm) with severe angulation of the proximal neck (>60°). The patient was considered unfit for traditional EVAR and open surgery. Possible alternatives such as fenestrated endovascular abdominal aortic aneurysm repair and chimney technique were excluded; therefore he was treated combining Valiant Captivia endoprosthesis with the AFX unibody, with a good final result. However, this particular alternative adopted for hostile proximal neck needs long-term follow-up.

  16. Mycotic Saccular Abdominal Aortic Aneurysm in an Infant after Cardiac Catheterization: A Case Report.

    PubMed

    Benrashid, Ehsan; McCoy, Christopher C; Rice, Henry E; Shortell, Cynthia K; Cox, Mitchell W

    2015-10-01

    Abdominal aortic aneurysms (AAAs) are a rare entity in the pediatric population. Children with mycotic (infectious) AAA in particular are at risk of life-threatening rupture due to their rapid expansion coupled with aortic wall thinning and deterioration. Here, we present the case of a 10-month-old infant with prior 2-staged repair for hypoplastic left heart syndrome that was incidentally discovered to have a mycotic AAA on abdominal ultrasound (US) for evaluation of renovascular hypertension. Before the time of evaluation with US, the infant had developed methicillin-resistant Staphylococcus aureus bacteremia 3 days after cardiac catheterization with percutaneous thoracic aortic balloon angioplasty. She had normal aortic contours on contrasted computed tomography scan of the abdomen approximately 2 weeks before the aforementioned US evaluation. This infant subsequently underwent open aneurysmorrhaphy with cryopreserved vein patch angioplasty with resolution of her aneurysmal segment.

  17. Logistic considerations for a successful institutional approach to the endovascular repair of ruptured abdominal aortic aneurysms.

    PubMed

    Mayer, Dieter; Rancic, Zoran; Pfammatter, Thomas; Hechelhammer, Lukas; Veith, Frank J; Donas, Konstantin; Lachat, Mario

    2010-01-01

    The value of emergency endovascular aneurysm repair (EVAR) in the setting of ruptured abdominal aortic aneurysm remains controversial owing to differing results. However, interpretation of published results remains difficult as there is a lack of generally accepted protocols or standard operating procedures. Furthermore, such protocols and standard operating procedures often are reported incompletely or not at all, thereby making interpretation of results difficult. We herein report our integrated logistic system for the endovascular treatment of ruptured abdominal aortic aneurysms. Important components of this system are prehospital logistics, in-hospital treatment logistics, and aftercare. Further studies should include details about all of these components, and a description of these logistic components must be included in all future studies of emergency EVAR for ruptured abdominal aortic aneurysms.

  18. A critical appraisal of endovascular stent-grafts in the management of abdominal aortic aneurysms.

    PubMed

    Schoretsanitis, Nikolaos; Georgakarakos, Efstratios; Argyriou, Christos; Ktenidis, Kiriakos; Georgiadis, George S

    2017-04-01

    Endovascular repair of abdominal aortic aneurysms has widely replaced the open surgical repair due to its minimal invasive nature and the accompanying lower perioperative mortality and morbidity. During the past two decades, certain improvements and developments have provided a wide variety of endograft structural designs and geometric patterns, enabling the physician to approach a more patient-specific treatment of AAA. This review presents the currently available aortic endografts and describes the clinical, technical and mechanical characteristics of them.

  19. Simulation of bifurcated stent grafts to treat abdominal aortic aneurysms (AAA)

    NASA Astrophysics Data System (ADS)

    Egger, J.; Großkopf, S.; Freisleben, B.

    2007-03-01

    In this paper a method is introduced, to visualize bifurcated stent grafts in CT-Data. The aim is to improve therapy planning for minimal invasive treatment of abdominal aortic aneurysms (AAA). Due to precise measurement of the abdominal aortic aneurysm and exact simulation of the bifurcated stent graft, physicians are supported in choosing a suitable stent prior to an intervention. The presented method can be used to measure the dimensions of the abdominal aortic aneurysm as well as simulate a bifurcated stent graft. Both of these procedures are based on a preceding segmentation and skeletonization of the aortic, right and left iliac. Using these centerlines (aortic, right and left iliac) a bifurcated initial stent is constructed. Through the implementation of an ACM method the initial stent is fit iteratively to the vessel walls - due to the influence of external forces (distance- as well as balloonforce). Following the fitting process, the crucial values for choosing a bifurcated stent graft are measured, e.g. aortic diameter, right and left common iliac diameter, minimum diameter of distal neck. The selected stent is then simulated to the CT-Data - starting with the initial stent. It hereby becomes apparent if the dimensions of the bifurcated stent graft are exact, i.e. the fitting to the arteries was done properly and no ostium was covered.

  20. [Quantitative changes of elastin, fibrillin and collagen in abdominal aortic aneurysms].

    PubMed

    Osakabe, T; Okada, N; Wachi, H; Sato, A; Sasaki, S; Wada, N; Seyama, Y

    2000-12-01

    To examine quantitative changes of elastin, fibrillin and collagen in abdominal aortic aneurysms, including ruptured abdominal aortic aneurysms (RAAA), inflammatory abdominal aortic aneurysms (IAAA) and abdominal aortic aneurysms (AAA) were measured. Items measured included the desmosine content of the aorta (desmosine 1) or of the elastin fraction (desmosine 2), fibrillin content in the aorta, hydroxyproline in the aorta, collagen percent and elastin percent, and were compared with control samples from the nonaneurysmal aortic segments. The elastin contents (desmosine 2) in RAAA, IAAA and AAA were significantly lower than those of controls. The content of the desmosine 2 from IAAA and AAA did not show a negative association with Ca. The fibrillin contents of the aorta from RAAA, IAAA and AAA were significantly higher than those of controls. The collagen content in the RAAA aorta was significantly higher than that of controls. There was a correlation of the ratio of fibrillin to elastin components (fibrillin/desmosine 1 or fibrillin/desmosine 2 or fibrillin/elastin%) and the ratio of collagen to elastin components (collagen/desmosine 1 or collagen/desmosine 2 or collagen/elastin%). These results indicated that increasing fibrillin and collagen might be a complementary result of decreasing elastin crosslinks in the aorta. This phenomenon was markedly in RAAA.

  1. Caval and ureteral obstruction secondary to an inflammatory abdominal aortic aneurysm.

    PubMed

    Kashyap, Vikram S; Fang, Raymond; Fitzpatrick, Colleen M; Hagino, Ryan T

    2003-12-01

    Inflammatory abdominal aortic aneurysms (IAAA) represent 3% to 10% of all abdominal aortic aneurysms. Obstructive uropathy is a well-described feature of IAAAs, but venous complications are unusual secondary to IAAA. The authors report a patient presenting with acute renal failure and deep venous thrombosis secondary to an IAAA. We believe this represents the first case of an IAAA manifesting as combined inferior vena cava compression and associated obstructive uropathy. Successful operative repair was performed. With resolution of the retroperitoneal inflammation, long-term follow-up revealed spontaneous release of both ureteral and caval compression.

  2. Inflammatory abdominal aortic aneurysm followed by disseminated intravascular coagulation and immune thrombocytopenia.

    PubMed

    Machida, Hisanori; Kobayashi, Makoto; Taguchi, Hirokuni

    2002-11-01

    A 71-year-old man was diagnosed as having an abdominal aortic aneurysm when he was treated for idiopathic interstitial pneumonia (IIP). Three years later, he developed severe thrombocytopenia and had disseminated intravascular coagulation (DIC) that was associated with the inflammatory abdominal aortic aneurysm (IAAA). The coagulation abnormalities were corrected by low-molecular weight heparin, however the platelet count remained low. Bone marrow showed normocellularity with an increase of immature and mature forms of megakaryocytes. Platelet-associated IgG level was high. These findings suggested that the patient had severe thrombocytopenia caused by unusual complications of immune thrombocytopenic purpura and IAAA-associated DIC.

  3. Surgical Treatment of a Voluminous Infrarenal Abdominal Aortic Aneurysm with Horseshoe Kidney: Tips and Tricks

    PubMed Central

    Massara, Mafalda; Greco, Michele; Mastrojeni, Claudio; Serra, Raffaele; Salomone, Ignazio; La Spada, Michele

    2015-01-01

    Horseshoe kidney is a common urology anomaly, while its association with infrarenal abdominal aortic aneurysm represents a very rare condition. Surgical approach remains controversial however, we believe that the left retroperitoneal approach should be preferred in order to avoid isthmus resection with any subsequent renal infarction, urinary tract damage and to facilitate renal arteries reimplantation, when required. We present a case of voluminous infrarenal abdominal aortic aneurysm associated with horseshoe kidney, successfully treated through a left retroperitoneal approach on the retro-renal space. PMID:26730260

  4. Renal flow studies after abdominal aortic aneurysmectomy and axillo-bifemoral bypass graft: case report

    SciTech Connect

    LaManna, M.M.; Yussen, P.S.

    1988-03-01

    Vascular disorders affecting the kidneys are either acquired or congenital. Included in this category are common multiplicity of renal arteries, the rare arteriovenous malformation, stresses due to fibromuscular disease or atherosclerosis including abdominal aortic aneurysms, arterial thrombosis, venous thrombosis, and infarction. In contrast to the group of cystic and neoplastic kidneys where scintigraphic or pathologic are not diagnostic, scintigraphic or pathologic anatomy in vascular disease is often diagnostic by nuclear medicine techniques. The authors present an interesting case of evaluation of acute renal failure in a patient abdominal aortic aneurysmectomy and axillo-bifemoral bypass graft.

  5. Soluble epoxide hydrolase inhibition does not prevent cardiac remodeling and dysfunction after aortic constriction in rats and mice.

    PubMed

    Morgan, Lisa A; Olzinski, Alan R; Upson, John J; Zhao, Shufang; Wang, Tao; Eisennagel, Stephen H; Hoang, Bao; Tunstead, James R; Marino, Joseph P; Willette, Robert N; Jucker, Beat M; Behm, David J

    2013-04-01

    Epoxyeicosatrienoic acids, substrates for soluble epoxide hydrolase (sEH), exhibit vasodilatory and antihypertrophic activities. Inhibitors of sEH might therefore hold promise as heart failure therapeutics. We examined the ability of sEH inhibitors GSK2188931 and GSK2256294 to modulate cardiac hypertrophy, fibrosis, and function after transverse aortic constriction (TAC) in rats and mice. GSK2188931 administration was initiated in rats 1 day before TAC, whereas GSK2256294 treatment was initiated in mice 2 weeks after TAC. Four weeks later, cardiovascular function was assessed, plasma was collected for drug and sEH biomarker concentrations, and left ventricle was isolated for messenger RNA and histological analyses. In rats, although GSK2188931 prevented TAC-mediated increases in certain genes associated with hypertrophy and fibrosis (α-skeletal actin and connective tissue growth factor), the compound failed to attenuate TAC-induced increases in left ventricle mass, posterior wall thickness, end-diastolic volume and pressure, and perivascular fibrosis. Similarly, in mice, GSK2256294 did not reverse cardiac remodeling or systolic dysfunction induced by TAC. Both compounds increased the sEH substrate/product (leukotoxin/leukotoxin diol) ratio, indicating sEH inhibition. In summary, sEH inhibition does not prevent cardiac remodeling or dysfunction after TAC. Thus, targeting sEH seems to be insufficient for reducing pressure overload hypertrophy.

  6. Predominance of Abdominal Visceral Adipose Tissue Reflects the Presence of Aortic Valve Calcification.

    PubMed

    Oikawa, Masayoshi; Owada, Takashi; Yamauchi, Hiroyuki; Misaka, Tomofumi; Machii, Hirofumi; Yamaki, Takayoshi; Sugimoto, Koichi; Kunii, Hiroyuki; Nakazato, Kazuhiko; Suzuki, Hitoshi; Saitoh, Shu-Ichi; Takeishi, Yasuchika

    2016-01-01

    Background. Aortic valve calcification (AVC) is a common feature of aging and is related to coronary artery disease. Although abdominal visceral adipose tissue (VAT) plays fundamental roles in coronary artery disease, the relationship between abdominal VAT and AVC is not fully understood. Methods. We investigated 259 patients who underwent cardiac and abdominal computed tomography (CT). AVC was defined as calcified lesion on the aortic valve by CT. %abdominal VAT was calculated as abdominal VAT area/total adipose tissue area. Results. AVC was detected in 75 patients, and these patients showed higher %abdominal VAT (44% versus 38%, p < 0.05) compared to those without AVC. When the cutoff value of %abdominal VAT was set at 40.9%, the area under the curve to diagnose AVC was 0.626. Multivariable logistic regression analysis showed that age (OR 1.120, 95% CI 1.078-1.168, p < 0.01), diabetes (OR 2.587, 95% CI 1.323-5.130, p < 0.01), and %abdominal VAT (OR 1.032, 95% CI 1.003-1.065, p < 0.05) were independent risk factors for AVC. The net reclassification improvement value for detecting AVC was increased when %abdominal VAT was added to the model: 0.5093 (95% CI 0.2489-0.7697, p < 0.01). Conclusion. We determined that predominance of VAT is associated with AVC.

  7. Endovascular treatment of a small infrarenal abdominal aortic aneurysm causing duodenal obstruction: Case report and literature review.

    PubMed

    Esposito, Andrea; Menna, Danilo; Mansour, Wassim; Sirignano, Pasqualino; Capoccia, Laura; Speziale, Francesco

    2015-06-01

    Duodenal obstruction caused by abdominal aortic aneurysm was first described by Osler in 1905 and is named "aortoduodenal syndrome." This condition has always been treated by open surgical repair. We report the first case of aortoduodenal syndrome successfully treated by endovascular aneurysm repair. A 74-year-old male patient referred to our hospital complaining postprandial vomit, reporting a consistent weight loss in the latest weeks. Enhanced computed tomography scans showed a small saccular abdominal aortic aneurysm compressing duodenum and inferior vena cava without any other evident pathological finding. As the patient underwent a successful endovascular treatment of the abdominal aortic aneurysm, symptoms immediately resolved so that he started back to feed and progressively gained body weight. Despite aortoduodenal syndrome is generally caused by large abdominal aortic aneurysm, this condition has to be suspected also in case of small abdominal aortic aneurysm. Differently from what has been reported in literature, endovascular aneurysm repair could be effective in the treatment of aortoduodenal syndrome.

  8. Inflammatory abdominal aortic aneurysm presenting as bilateral hydroureteronephrosis: a case report and review of literature.

    PubMed

    Galosi, Andrea Benedetto; Grilli Cicilioni, Carlo; Sbrollini, Giulia; Angelini, Andrea; Maselli, Guevar; Carbonari, Luciano

    2014-12-30

    We report a case of Inflammatory Abdominal Aortic Aneurysm (IAAA) producing bilateral hydro-ureteronephrosis. A 74-year-old patient presented to urologist office for bilateral hydronephrosis detected by kidney and bladder ultrasound (US). Patient reported lower urinary tract symptoms and inconstant and slight low back pain irradiated to inguinal region dating 3 weeks. Renal function, urine analysis and abdominal examination were normal. However the repeated ultrasound in the urologist office revealed abdominal aortic aneurism extended to iliac vessels. The patient was sent directly to vascular surgery unit where contrast computerized tomography (CT) and successful surgical repair were done. Final diagnosis was IAAA. The post-operative course was uneventful. Renal function was regular and the hydronephrosis reduced spontaneously under monitoring by CT and US. We review diagnosis and management of hydronephrosis that is sometimes linked to IAAA rather than standard AAA. Abdominal ultrasound is mandatory in any bilateral hydronephrosis and it could save lives.

  9. Risk Stratification of Patients with Peripheral Arterial Disease and Abdominal Aortic Aneurysm Using Aortic Augmentation Index

    PubMed Central

    Beckmann, Marianne; Husmann, Marc

    2015-01-01

    Background Central augmentation index (cAIx) is an indicator for vascular stiffness. Obstructive and aneurysmatic vascular disease can affect pulse wave propagation and reflection, causing changes in central aortic pressures. Aim To assess and compare cAIx in patients with peripheral arterial disease (PAD) and / or abdominal aortic aneurysm (AAA). Methods cAIx was assessed by radial applanation tonometry (Sphygmocor) in a total of 184 patients at a tertiary referral centre. Patients were grouped as having PAD only, AAA only, or both AAA and PAD. Differences in cAIx measurements between the three patient groups were tested by non-parametric tests and stepwise multivariate linear regression analysis to investigate associations with obstructive or aneurysmatic patterns of vascular disease. Results In the study sample of 184 patients, 130 had PAD only, 20 had AAA only, and 34 patients had both AAA and PAD. Mean cAIx (%) was 30.5 ± 8.2 across all patients. It was significantly higher in females (35.2 ± 6.1, n = 55) than males (28.4 ± 8.2, n = 129), and significantly higher in patients over 80 years of age (34.4 ± 6.9, n = 22) than in those under 80 years (30.0 ± 8.2, n = 162). Intergroup comparison revealed a significant difference in cAIx between the three patient groups (AAA: 27.3 ± 9.5; PAD: 31.4 ± 7.8; AAA & PAD: 28.8 ± 8.5). cAIx was significantly lower in patients with AAA, higher in patients with both AAA and PAD, and highest in patients with PAD only (beta = 0.21, p = 0.006). Conclusion Non-invasive assessment of arterial stiffness in high-risk patients indicates that cAIx differs according to the pattern of vascular disease. Measurements revealed significantly higher cAIx values for patients with obstructive peripheral arterial disease than for patients with aneurysmatic disease. PMID:26452151

  10. Management of a large abdominal aortic aneurysm in conjunction with a massive inguinal hernia.

    PubMed

    Wartman, Sarah M; Woo, Karen; Brewer, Michael; Weaver, Fred A

    2017-04-04

    The majority of inguinal hernias that are concomitant with abdominal aortic aneurysms (AAA) are clinically insignificant. However, management of AAA associated with a complex hernia can be challenging. We report a case of a 72-year-old male with a 7 cm AAA and a massive inguinal hernia involving loss of abdominal domain. Using a multidisciplinary approach, a staged hybrid endovascular and open repair of the AAA was performed followed by hernia repair.

  11. Immunoglobulin G4-Related Inflammatory Abdominal Aortic Aneurysm Associated With Myasthenia Gravis, With Contained Rupture.

    PubMed

    Jun, Heungman; Jung, Cheol Woong

    2016-11-01

    Immunoglobulin (Ig) G4-related disease is reportedly among the various causes of inflammatory abdominal aortic aneurysm (IAAA). Many IgG4-related diseases are closely related to allergic constitution and autoimmune disease. We report a case of a 72-year-old man with IgG4-related IAAA associated with myasthenia gravis, with contained rupture.

  12. Association of ficolin-3 with abdominal aortic aneurysm presence and progression.

    PubMed

    Fernandez-García, C-E; Burillo, E; Lindholt, J S; Martinez-Lopez, D; Pilely, K; Mazzeo, C; Michel, J-B; Egido, J; Garred, P; Blanco-Colio, L M; Martin-Ventura, J L

    2017-03-01

    Essentials Abdominal aortic aneurysm (AAA) is asymptomatic and its evolution unpredictable. To find novel potential biomarkers of AAA, microvesicles are an excellent source of biomarkers. Ficolin-3 is increased in microvesicles obtained from activated platelets and AAA tissue. Increased ficolin-3 plasma levels are associated with AAA presence and progression.

  13. The influence of computational assumptions on analysing abdominal aortic aneurysm haemodynamics.

    PubMed

    Ene, Florentina; Delassus, Patrick; Morris, Liam

    2014-08-01

    The variation in computational assumptions for analysing abdominal aortic aneurysm haemodynamics can influence the desired output results and computational cost. Such assumptions for abdominal aortic aneurysm modelling include static/transient pressures, steady/transient flows and rigid/compliant walls. Six computational methods and these various assumptions were simulated and compared within a realistic abdominal aortic aneurysm model with and without intraluminal thrombus. A full transient fluid-structure interaction was required to analyse the flow patterns within the compliant abdominal aortic aneurysms models. Rigid wall computational fluid dynamics overestimates the velocity magnitude by as much as 40%-65% and the wall shear stress by 30%-50%. These differences were attributed to the deforming walls which reduced the outlet volumetric flow rate for the transient fluid-structure interaction during the majority of the systolic phase. Static finite element analysis accurately approximates the deformations and von Mises stresses when compared with transient fluid-structure interaction. Simplifying the modelling complexity reduces the computational cost significantly. In conclusion, the deformation and von Mises stress can be approximately found by static finite element analysis, while for compliant models a full transient fluid-structure interaction analysis is required for acquiring the fluid flow phenomenon.

  14. Helicobacter pylori Eradication Therapy for Thrombocytopenia after Surgery for Abdominal Aortic Aneurysm with Disseminated Intravascular Coagulation

    PubMed Central

    Akiyama, Daichi; Okada, Hiroshi; Date, Kazuma; Furukawa, Hiroshi; Takeda, Makoto

    2016-01-01

    Abdominal aortic aneurysm (AAA) is known to be rarely accompanied by disseminated intravascular coagulation (DIC). We report a case of AAA with DIC. An 81-year-old man with abdominal pain referred to our hospital. Computed tomography demonstrated an AAA (maximum diameter: 90 mm). The patient underwent a laparotomy, and an abdominal aorta replacement was performed. At the 3-month follow-up, the patient underwent Helicobacter pylori eradication treatment for 1 week. After treatment, the platelet count dramatically increased. The mechanism by which H. pylori eradication therapy improves hematological parameters has not been elucidated; however, this noninvasive treatment effectively resolved DIC associated with AAA. PMID:28018509

  15. Repair of anastomotic abdominal aortic pseudoaneurysm utilizing sequential AneuRx aortic cuffs in an overlapping configuration.

    PubMed

    Zhou, Wei; Bush, Ruth L; Bhama, Jay K; Lin, Peter H; Safaya, Rakesh; Lumsden, Alan B

    2006-01-01

    Anastomotic aortic pseudoaneurysm is a known late complication following aortic repair and presents a considerable surgical challenge. We herein evaluate the endovascular alternative of using sequential AneuRx aortic cuffs to bridge the degenerative anastomotic pseudoaneurysms as a definitive treatment. Over a 3-year period, six patients with a mean age of 68.7 years (range 58-75) were identified who had proximal anastomotic aortic pseudoaneurysms secondary to previously implanted bifurcated aortic grafts (mean 15, range 12-20 years) following open surgical correction of aortoiliac occlusive disease. Five patients (83%) presented with concomitant palpable femoral anastomotic pseudoaneurysms and one patient (16%) had a pulsatile abdominal mass. All patients had computed tomographic (CT) scans confirming proximal anastomotic pseudoaneuryms without evidence of infection. The mean diameter of the pseudoaneurysms was 5.3 cm (range 4.0-7.0). Five patients were treated with endovascular methods, while one patient was not suitable for endovascular repair due to the diameter of the native aorta as seen on imaging study at the time of the procedure. AneuRx aortic extender cuffs (3.75 cm length) were deployed sequentially in five patients via a femoral approach. Devices were overlapped approximately 1.5 cm in order to achieve total exclusion of the pseudoaneurysms, and all concomitant femoral aneurysms were repaired surgically at the same time. Successful exclusion of the anastomotic pseudoaneurysm was achieved in four patients (80%) using a combination of two or three overlapping aortic cuffs. One patient had a small residual endoleak that had sealed by 1 month, evidenced by follow-up CT. The renal arteries were preserved in all patients. The average estimated blood loss and operative time were 355 +/- 25 cc and 84 +/- 21 min, respectively. The average length of hospital stay was 2.1 days, and there was no mortality or major morbidity. All patients underwent CT scanning

  16. The interaction of transient receptor potential melastatin 7 with macrophages promotes vascular adventitial remodeling in transverse aortic constriction rats.

    PubMed

    Li, Yan; Jiang, Hui; Ruan, Chengchao; Zhong, Jiuchang; Gao, Pingjin; Zhu, Dingliang; Niu, Wenquan; Guo, Shujie

    2014-01-01

    Transient receptor potential melastatin 7 (TRPM7), a novel channel kinase, has been recently identified in the vasculature. However, its regulation and function in vascular diseases remain poorly understood. To address this lack of knowledge, we sought to examine whether TRPM7 can mediate the vascular remodeling process induced by pressure overload in the right common carotid artery proximal to the band (RCCA-B) in male Sprague-Dawley rats with transverse aortic constriction (TAC). The contribution of TRPM7 to amplified vascular remodeling after TAC was tested using morphometric and western blot analyses. Pressure overload-induced vascular wall thickening, especially in the adventitia, was readily detected in RCCA-B. The TRPM7 level was increased with a simultaneous accumulation of macrophages in the adventitia of RCCA-B, whereas the anti-inflammatory molecule annexin-1, a TRPM7 downstream target, was decreased. After the addition of the TRPM7 inhibitor 2-aminoethoxydiphenyl borate (2-APB), significant reductions in macrophage accumulation as well as the expression of monocyte chemotactic protein-1, SM-22-α and collagen I were observed, whereas annexin-1 was rescued. Finally, in cultured vascular adventitial fibroblasts treated with macrophage-conditioned medium, there were marked increases in the expression of TRPM7 and SM-22-α with a concurrent reduction in annexin-1 expression; these effects were largely prevented by treatment with 2-APB and specific anti-TRPM7 small interfering RNA. Our findings provide the first demonstration of the potential regulatory roles of TRPM7 in the vascular inflammation, pressure overload-mediated vascular adventitial collagen accumulation and cell phenotypic transformation in TAC rats. The targeting of TRPM7 has potential therapeutic importance for vascular diseases.

  17. Innovative Chimney-Graft Technique for Endovascular Repair of a Pararenal Abdominal Aortic Aneurysm

    PubMed Central

    Galiñanes, Edgar Luis; Hernandez-Vila, Eduardo A.

    2015-01-01

    After abdominal aortic aneurysm repair, progressive degeneration of the aneurysm can be challenging to treat. Multiple comorbidities and previous operations place such patients at high risk for repeat surgery. Endovascular repair is a possible alternative; however, challenging anatomy can push the limits of available technology. We describe the case of a 71-year-old man who presented with a 5.3-cm pararenal aneurysm 4 years after undergoing open abdominal aortic aneurysm repair. To avoid reoperation, we excluded the aneurysm by endovascular means, using visceral-artery stenting, a chimney-graft technique. Low-profile balloons on a monorail system enabled the rapid exchange of coronary wires via a buddy-wire technique. This novel approach facilitated stenting and simultaneous angioplasty of multiple visceral vessels and the abdominal aorta. PMID:25873796

  18. The preventive effect of fish oil on abdominal aortic aneurysm development.

    PubMed

    Kugo, Hirona; Zaima, Nobuhiro; Mouri, Youhei; Tanaka, Hiroki; Yanagimoto, Kenichi; Urano, Tetsumei; Unno, Naoki; Moriyama, Tatsuya

    2016-06-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving gradual dilation of the abdominal aorta and high rupture-related mortality rates. AAA is histologically characterized by oxidative stress, chronic inflammation, and extracellular matrix degradation in the vascular wall. We previously demonstrated that aortic hypoperfusion could cause the vascular inflammation and AAA formation. However, the preventive method for hypoperfusion-induced AAA remains unknown. In this study, we evaluated the effect of fish oil on AAA development using a hypoperfusion-induced AAA animal model. Dilation of the abdominal aorta in the fish oil administration group was smaller than in the control group. Collagen destruction and oxidative stress were suppressed in the fish oil administration group than in the control group. These results suggested that fish oil could prevent the development of AAA induced by hypoperfusion.

  19. Spectrum of Abdominal Aortic Disease in a Tertiary Health Care Setup: MDCT Based Observational Study

    PubMed Central

    Kumar, DG Santosh; Gadabanahalli, Karthik; Kalyanpur, Arjun

    2016-01-01

    Introduction Abdominal aortic disease is an important cause of clinical disability that requires early detection by imaging methods for prompt and effective management. Understanding regional disease pattern and prevalence has a bearing on healthcare management and resource planning. Non-invasive, conclusive imaging strategy plays an important role in the detection of disease. Multi-Detector Computed Tomography (MDCT) with its technological developments provides affordable, accurate and comprehensive imaging solution. Aim To evaluate regional demography of abdominal aortic disease spectrum detected using MDCT imaging data in a tertiary hospital. Materials and Methods A descriptive study was conducted based on MDCT imaging data of patients who were investigated with clinical diagnosis of abdominal aortic disease, from March 2008-2010, over a period of 24 months. Patients were examined with the contrast-enhanced MDCT examination. Morphological diagnosis of the aortic disease was based on changes in relative aortic caliber, luminal irregularity, presence of wall calcification, dissection or thrombus and evidence of major branch occlusion. Patients were categorized into four groups based on imaging findings. MDCT information and associated clinical parameters were examined and correlated to management of patient. Descriptive statistical data, namely mean, standard deviation and frequency of disease were evaluated. Results A total of 90 out of 210 patients (43%) were detected with the abdominal aortic abnormality defined by imaging criteria. Group I, comprising of patients with atherosclerosis –including those with complications, constituted 65.5% of the patients. Group II represented patients with aneurysms (45.5%). Group III, consisting of 32.2% of the patients, contained those with dissections. The rest of the patients, including patients with aorto-arteritis, were classified as group IV. Eight patients with aneurysm and one patient with aorto-arteritis were

  20. Extra-anatomic endovascular repair of an abdominal aortic aneurysm with a horseshoe kidney supplied by the aneurysmal aorta.

    PubMed

    Rey, Jorge; Golpanian, Samuel; Yang, Jane K; Moreno, Enrique; Velazquez, Omaida C; Goldstein, Lee J; Chahwala, Veer

    2015-07-01

    Abdominal aortic aneurysm complicated by a horseshoe kidney (HSK, fused kidney) represents a unique challenge for repair. Renal arteries arising from the aneurysmal aorta can further complicate intervention. Reports exist describing the repair of these complex anatomies using fenestrated endografts, hybrid open repairs (debranching), and open aneurysmorrhaphy with preservation of renal circulation. We describe an extra-anatomic, fully endovascular repair of an abdominal aortic aneurysm with a HSK partially supplied by a renal artery arising from the aneurysm. We successfully applied aortouni-iliac endografting, femorofemoral bypass, and retrograde renal artery perfusion via the contralateral femoral artery to exclude the abdominal aortic aneurysm and preserve circulation to the HSK.

  1. Nuclear cardiac ejection fraction and cardiac index in abdominal aortic surgery

    SciTech Connect

    Fiser, W.P.; Thompson, B.W.; Thompson, A.R.; Eason, C.; Read, R.C.

    1983-11-01

    Since atherosclerotic heart disease results in more than half of the perioperative deaths that follow abdominal aortic surgery, a prospective protocol was designed for preoperative evaluation and intraoperative hemodynamic monitoring. Twenty men who were prepared to undergo elective operation for aortoiliac occlusive disease (12 patients) and abdominal aortic aneurysm (eight patients) were evaluated with a cardiac scan and right heart catheterization. The night prior to operation, each patient received volume loading with crystalloid based upon ventricular performance curves. At the time of the operation, all patients were anesthetized with narcotics and nitrous oxide, and hemodynamic parameters were recorded throughout the operation. Aortic crossclamping resulted in a marked depression in CI in all patients. CI remained depressed after unclamping in the majority of patients. There were two perioperative deaths, both from myocardial infarction or failure. Both patients had ejection fractions less than 30% and initial CIs less than 2 L/M2, while the survivors' mean ejection fraction was 63% +/- 1 and their mean CI was 3.2 L/M2 +/- 0.6. The authors conclude that preoperative evaluation of ejection fraction can select those patients at a high risk of cardiac death from abdominal aortic operation. These patients should receive intensive preoperative monitoring with enhancement of ventricular performance.

  2. Aortocaval fistula in ruptured inflammatory abdominal aortic aneurysm. A report of two cases and literature review.

    PubMed

    Farid, A; Sullivan, T M

    1996-12-01

    Inflammatory abdominal aortic aneurysms (IAAA) occur infrequently in clinical practice. The reported incidence varies from 2.5-15% of all abdominal aortic aneurysms (AAA). Four percent of all AAA rupture into the vena cava. IAAA rupturing into the vena cava is exceedingly rare. To date, four such cases have been reported. IAAA are associated with a thick, rigid aortic wall which may be thin posteriorly and posterolaterally, where they are likely to rupture. A dense, fibrotic, desmoplastic reaction is found in the periaortic tissues often involving the duodenum, the inferior vena cava, the left renal vein, and ureters. IAAA may present with abdominal, back, or flank pain even in the absence of rupture. The diagnosis of IAAA can be made preoperatively by CT scan and at the time of laparotomy. Aortocaval fistula (ACF) can occur as a complication of AAA. The triad of low back pain, a palpable AAA, and a machinery murmur is diagnostic. ACF in association with IAAA is even more rare. It is amenable to surgical correction using a standard technique of fistula repair from within the aneurysm and prosthetic aortic graft replacement. Two cases of AAA with aortocaval fistula (ACF) are presented. In both, the diagnosis of ACF was made preoperatively. Repair of ACF was performed from within the aneurysm, with subsequent graft replacement. Despite complicated postoperative courses, both patients survived.

  3. On the prediction of monocyte deposition in abdominal aortic aneurysms using computational fluid dynamics.

    PubMed

    Hardman, David; Doyle, Barry J; Semple, Scott I K; Richards, Jennifer M J; Newby, David E; Easson, William J; Hoskins, Peter R

    2013-10-01

    In abdominal aortic aneurysm disease, the aortic wall is exposed to intense biological activity involving inflammation and matrix metalloproteinase-mediated degradation of the extracellular matrix. These processes are orchestrated by monocytes and rather than affecting the aorta uniformly, damage and weaken focal areas of the wall leaving it vulnerable to rupture. This study attempts to model numerically the deposition of monocytes using large eddy simulation, discrete phase modelling and near-wall particle residence time. The model was first applied to idealised aneurysms and then to three patient-specific lumen geometries using three-component inlet velocities derived from phase-contrast magnetic resonance imaging. The use of a novel, variable wall shear stress-limiter based on previous experimental data significantly improved the results. Simulations identified a critical diameter (1.8 times the inlet diameter) beyond which significant monocyte deposition is expected to occur. Monocyte adhesion occurred proximally in smaller abdominal aortic aneurysms and distally as the sac expands. The near-wall particle residence time observed in each of the patient-specific models was markedly different. Discrete hotspots of monocyte residence time were detected, suggesting that the monocyte infiltration responsible for the breakdown of the abdominal aortic aneurysm wall occurs heterogeneously. Peak monocyte residence time was found to increase with aneurysm sac size. Further work addressing certain limitations is needed in a larger cohort to determine clinical significance.

  4. Abdominal aortic aneurysm repair in a patient with a congenital solitary pelvic kidney. A case report.

    PubMed

    Murakami, T; Makino, Y; Suto, Y; Yasuda, K

    2004-10-01

    Abdominal aortic aneurysm (AAA) is rarely associated witha congenital pelvic kidney. To date only 11 cases have been reported in the literature in which a solitary pelvic' kidney was associated in only 1 patient. Repair of thesaneurysm is technically demanding because the abnormal origin of the renal arteries presents the problem of renal ischemia duringaortic cross-clamping. We report a case of a 77-year-old man who was found to have an AAA associated with a congenital solitary pelvic kidney. An abdominal aortography dearly showed 2 aberrant renal arteries, one of which originated from the aortic wall just above the aortic bifurcation and the other from the left common iliac artery. At surgery, we found other associated anomalies including malrotation of the gut and a left undescended testis. The surgical procedure consisted of an aneurysmorrhaphy followed by a tube graft replacement with therenal arteries being left intact to the distal aortic wall or below. Renal preservation during aortic cross-clamping was achieved by direct perfusion of the upper renal artery with cold lactated Ringer's solution together with topical cooling with ice slush. The patient's postoperative course was uneventful. Urinary output was satisfactory and serum creatinine level remained unchanged throughout his hospital stay. The renal preservation method used in this case was simple and effective.

  5. c-Myc alters substrate utilization and O-GlcNAc protein posttranslational modifications without altering cardiac function during early aortic constriction

    SciTech Connect

    Ledee, Dolena; Smith, Lincoln; Bruce, Margaret; Kajimoto, Masaki; Isern, Nancy; Portman, Michael A.; Olson, Aaron K.; Bertrand, Luc

    2015-08-12

    Pressure overload cardiac hypertrophy alters substrate metabolism. Prior work showed that myocardial inactivation of c-Myc (Myc) attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we hypothesize that Myc regulates substrate preferences for the citric acid cycle during pressure overload hypertrophy from transverse aortic constriction (TAC) and that these metabolic changes impact cardiac function and growth. To test this hypothesis, we subjected mice with cardiac specific, inducible Myc inactivation (MycKO-TAC) and non-transgenic littermates (Cont-TAC) to transverse aortic constriction (TAC; n=7/group). A separate group underwent sham surgery (Sham, n=5). After two weeks, function was measured in isolated working hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. Compared to Sham, Cont-TAC had increased free fatty acid fractional contribution with a concurrent decrease in unlabeled (predominately glucose) contribution. The changes in free fatty acid and unlabeled fractional contributions were abrogated by Myc inactivation during TAC (MycKO-TAC). Additionally, protein posttranslational modification by O-GlcNAc was significantly greater in Cont-TAC versus both Sham and MycKO-TAC. Lastly, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy.

  6. c-Myc alters substrate utilization and O-GlcNAc protein posttranslational modifications without altering cardiac function during early aortic constriction

    DOE PAGES

    Ledee, Dolena; Smith, Lincoln; Bruce, Margaret; ...

    2015-08-12

    Pressure overload cardiac hypertrophy alters substrate metabolism. Prior work showed that myocardial inactivation of c-Myc (Myc) attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we hypothesize that Myc regulates substrate preferences for the citric acid cycle during pressure overload hypertrophy from transverse aortic constriction (TAC) and that these metabolic changes impact cardiac function and growth. To test this hypothesis, we subjected mice with cardiac specific, inducible Myc inactivation (MycKO-TAC) and non-transgenic littermates (Cont-TAC) to transverse aortic constriction (TAC; n=7/group). A separate group underwent sham surgery (Sham, n=5). After two weeks, function was measured in isolated workingmore » hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. Compared to Sham, Cont-TAC had increased free fatty acid fractional contribution with a concurrent decrease in unlabeled (predominately glucose) contribution. The changes in free fatty acid and unlabeled fractional contributions were abrogated by Myc inactivation during TAC (MycKO-TAC). Additionally, protein posttranslational modification by O-GlcNAc was significantly greater in Cont-TAC versus both Sham and MycKO-TAC. Lastly, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy.« less

  7. [The operations of the abdominal hernias with the use propylene material in patients operated due to abdominal aortic aneurysm].

    PubMed

    Pupka, Artur; Lepiesza, Agnieszka; Skóra, Jan; Nega, Katarzyna

    2011-01-01

    The correlation between abdominal hernias and aortic aneurysm has been well documented in literature. The pathophysiology of aneurysm and hernia formation is seen within the abnormal collagen metabolism, resulting in extracellular matrix defects. This study presents a group of 8 men in the age of 36 to 78 years old (average 63, 5 years old) who underwent both an operation for the aneurysm and for the abdominal hernia. Of the reported 8 patients, 7 had postoperative hernias, where 4 of the cases there were recurrent postoperative hernias. The remaining patient had an inguinal hernia. In 7 cases patients underwent an abdominal aortic aneurysm (AAA) operation and in one case a hepatic artery aneurysm endovascular operation was performed. Due to the fact that postoperative hernias are an immense problem, especially within the group of patient with collagen defects, the area of research and improvement of the materials that are used in prosthetic hernia surgery today needs to progress. This study also presents a short review of the various types of prosthetic materials used in the production of hernial meshes. This is to emphasize the necessity of improving operational techniques to minimize the risk of herniation, especially within a group of patients with collagen defects.

  8. Human thoracic and abdominal aortic aneurysmal tissues: Damage experiments, statistical analysis and constitutive modeling.

    PubMed

    Pierce, David M; Maier, Franz; Weisbecker, Hannah; Viertler, Christian; Verbrugghe, Peter; Famaey, Nele; Fourneau, Inge; Herijgers, Paul; Holzapfel, Gerhard A

    2015-01-01

    Development of aortic aneurysms includes significant morphological changes within the tissue: collagen content increases, elastin content reduces and smooth muscle cells degenerate. We seek to quantify the impact of these changes on the passive mechanical response of aneurysms in the supra-physiological loading range via mechanical testing and constitutive modeling. We perform uniaxial extension tests on circumferentially and axially oriented strips from five thoracic (65.6 years ± 13.4, mean ± SD) and eight abdominal (63.9 years ± 11.4) aortic fusiform aneurysms to investigate both continuous and discontinuous softening during supra-physiological loading. We determine the significance of the differences between the fitted model parameters: diseased thoracic versus abdominal tissues, and healthy (Weisbecker et al., J. Mech. Behav. Biomed. Mater. 12, 93-106, 2012) versus diseased tissues. We also test correlations among these parameters and age, Body Mass Index (BMI) and preoperative aneurysm diameter, and investigate histological cuts. Tissue response is anisotropic for all tests and the anisotropic pseudo-elastic damage model fits the data well for both primary loading and discontinuous softening which we interpret as damage. We found statistically relevant differences between model parameters fitted to diseased thoracic versus abdominal tissues, as well as between those fitted to healthy versus diseased tissues. Only BMI correlated with fitted model parameters in abdominal aortic aneurysmal tissues.

  9. Endovascular repair of inflammatory abdominal aortic aneurysm: serial changes of periaortic fibrosis demonstrated by CT.

    PubMed

    Sueyoshi, Eijun; Sakamoto, Ichiro; Uetani, Masataka

    2009-07-01

    Inflammatory abdominal aortic aneurysm (IAAA) is characterized by inflammatory and/or fibrotic changes in the periaortic regions of the retroperitoneum. Surgical repair is usually selected for this disease. However, the perioperative mortality associated with open surgical repair of IAAs is three times higher than that with noninflammatory aortic aneurysms due to inflammation and periaortic fibrosis (PAF). Endovascular aneurysm repair of IAAs excludes the aneurysm and seems to reduce the size of the aneurysmal sac and the extent of PAF with acceptable peri-interventional and long-term morbidity. We describe the successful endovascular repair of an IAAA and the serial CT findings after repair.

  10. Repair of Traumatic Abdominal Aortic Pseudoaneurysm Using N-Butyl-2-Cyano-Acrylate Embolization

    SciTech Connect

    Kawai, Nobuyuki; Sato, Morio Tanihata, Hirohiko; Sahara, Shinya; Takasaka, Isao; Minamiguchi, Hiroki; Nakai, Motoki

    2010-04-15

    Embolization using N-butyl-2-cyano-acrylate (NBCA) has been highly regarded for treating pseudoaneurysm, arteriovenous malformation, and hemorrhage of the visceral arteries. We report the case of a patient who fell from a cliff and sustained hemorrhagic shock with blunt abdominal aortic rupture and who underwent embolization using NBCA. This treatment achieved immediate hemostasis and stabilization of vital signs. Although the long-term durability of NBCA is unknown, it appears that certain types of acute aortic hemorrhage with narrow-necked pseudoaneurysm can be controlled by embolization using NBCA.

  11. Factors influencing the long-term results of abdominal aortic aneurysm repair.

    PubMed

    Geroulakos, G; Lumley, J S; Wright, J G

    1997-01-01

    The incidence of late graft complications such as para-anastomotic aneurysms, aortoenteric fistulas and graft infections following abdominal aortic aneurysm (AAA) repair is a major determinant of its overall benefit, yet most published reports of AAA repair have concentrated almost exclusively on the early postoperative mortality and morbidity. Accurate knowledge regarding the incidence of late complications is essential to making any decision regarding the operative vs nonoperative management of AAAs. A similar analysis must be applied to endovascular repair of AAAs before this technique is accepted as an alternative method of treating AAAs. In this article we review the current knowledge and understanding on the late results following aortic aneurysm repair.

  12. Acute rectal ischaemia following emergency abdominal aortic aneurysm surgery

    PubMed Central

    Mosley, Frances R.; Akhtar, Sobia; George, Rina; Pillay, Woolagasen R.

    2016-01-01

    We present a case of isolated rectal ischaemia, a rare complication after emergency surgery for a ruptured abdominal aneurysm. We discuss the possible aetiology of this condition and how this rare condition may be missed unless care is taken at the time of reoperation. PMID:28344761

  13. Lower limb myalgias in a man who used to "climb the stairs": an atypical abdominal aortic aneurysm.

    PubMed

    Dognini, Giuseppina Patrizia; Cadeo, Gianluca; Dolcino, Luigi; Gilardoni, Lodovico; Stringhi, Enrico; Forloni, Franco

    2012-07-01

    Atypical presentation of emergency abdominal aortic aneurysm comprises a wide spectrum of symptoms. Lower limbs' involvement is infrequent, usually monolateral and with clear vascular features. We report the case of a 58-year-old patient who complained exclusively about symmetric lower limb myalgias without vascular features, after having repeatedly climbed the stairs of the school he worked in. The surprising final diagnosis was of rupturing abdominal aortic aneurysm; the patient was sent to emergency surgery and survived.

  14. Aortoiliac Artery Reconstruction Using Bilateral Reversed Superficial Femoral Veins for an Infected Abdominal Aortic Aneurysm

    PubMed Central

    Hirai, Hanako; Yasuhara, Kiyomitsu; Hatori, Kyohei; Miki, Takao; Obayashi, Tamiyuki

    2016-01-01

    Surgical treatment of an infected abdominal aortic aneurysm (IAAA) is difficult and the ideal graft material is a subject of debate. A 60-year-old man with untreated diabetes mellitus was referred to our hospital presenting with fever and left lower abdominal pain. The patient was diagnosed with an IAAA by blood culture and computed tomography. We treated the patient surgically for the IAAA using bilateral reversed superficial femoral veins which were shaped into a bifurcated graft. No signs of recurrent infection or aneurysmal dilation were observed for 3 years after the procedure. PMID:27087879

  15. Aortoiliac Artery Reconstruction Using Bilateral Reversed Superficial Femoral Veins for an Infected Abdominal Aortic Aneurysm.

    PubMed

    Ohki, Satoshi; Hirai, Hanako; Yasuhara, Kiyomitsu; Hatori, Kyohei; Miki, Takao; Obayashi, Tamiyuki

    2016-01-01

    Surgical treatment of an infected abdominal aortic aneurysm (IAAA) is difficult and the ideal graft material is a subject of debate. A 60-year-old man with untreated diabetes mellitus was referred to our hospital presenting with fever and left lower abdominal pain. The patient was diagnosed with an IAAA by blood culture and computed tomography. We treated the patient surgically for the IAAA using bilateral reversed superficial femoral veins which were shaped into a bifurcated graft. No signs of recurrent infection or aneurysmal dilation were observed for 3 years after the procedure.

  16. Simultaneous xanthogranulomatous cholecystitis and gallbladder cancer in a patient with a large abdominal aortic aneurysm.

    PubMed

    Al-Abed, Yahya; Elsherif, Mohammed; Firth, John; Borgstein, Rudi; Myint, Fiona

    2012-09-01

    There have been reports of the coexistence of abdominal aortic aneurysm (AAA) with intra-abdominal malignancy including gastric, colonic, pancreatic, and renal. We herein report a case of a previously undiagnosed AAA and a presenting complaint consistent with acute cholecystitis. Following cholecystectomy, this was noted to be a rare form of chronic cholecystitis: xanthogranulomatous cholecystitis. There is a known possible association of this uncommon condition with gallbladder cancer. The management of concomitant pathologies can present a real challenge to the multidisciplinary team, especially with large aneurysms.

  17. Listeriosis Infection of an Abdominal Aortic Aneurysm in a Diabetic Patient

    PubMed Central

    Papadoulas, Spyros I; Kakkos, Stavros K; Kraniotis, Pantelis A; Manousi, Maria E; Marangos, Markos N; Tsolakis, Ioannis A

    2013-01-01

    A rare case of an abdominal aortic aneurysm (AAA) infected by Listeria monocytogenes in a 72-year-old male diabetic farmer, is reported. Our patient had a history of a recent pneumonia that could have been caused by Listeria too. Aneurysm infection was manifested by fever and abdominal and back pain, which prompted investigation with CT scanning that revealed a 4.9 cm AAA with typical signs of infection. He underwent urgent AAA repair with aortobifemoral bypass grafting and had an uneventful course. Aneurysm content microbiology revealed Listeria monocytogenes and following a 9-week course of antibiotics our patient remains asymptomatic 11 months later. PMID:23599616

  18. Extracellular Matrix Disarray as A Mechanism for Greater Abdominal vs. Thoracic Aortic Stiffness with Aging in Primates

    PubMed Central

    Zhang, Jie; Zhao, Xin; Vatner, Dorothy E; McNulty, Tara; Bishop, Sanford; Sun, Zhe; Shen, You-Tang; Chen, Li; Meininger, Gerald A; Vatner, Stephen F

    2016-01-01

    Objective Increased vascular stiffness is central to the pathophysiology of aging, hypertension, diabetes and atherosclerosis. However, relatively few studies have examined vascular stiffness in both the thoracic and abdominal aorta with aging, despite major differences in anatomy, embryological origin and relation to aortic aneurysm. Approach and Results The two other unique features of this study were 1) to study young (9±1 years) and old (26±1 years) male monkeys, and 2) to study direct and continuous measurements of aortic pressure and thoracic and abdominal aortic diameters in conscious monkeys. As expected, aortic stiffness, β, was increased p<0.05, 2–3 fold, in old vs. young thoracic aorta, and augmented further with superimposition of acute hypertension with phenylephrine. Surprisingly, stiffness was not greater in old thoracic aorta than young abdominal aorta. These results can be explained in part by the collagen/elastin ratio, but more importantly, by disarray of collagen and elastin, which correlated best with vascular stiffness. However, vascular smooth muscle cell stiffness, was not different in thoracic vs. abdominal aorta in either young or old monkeys. Conclusions Thus, aortic stiffness increases with aging as expected, but the most severe increases in aortic stiffness observed in the abdominal aorta is novel, where values in young monkeys equaled, or even exceeded, values of thoracic aortic stiffness in old monkeys. These results can be explained by alterations in collagen/elastin ratio, but even more importantly by collagen and elastin disarray. PMID:26891739

  19. Current status of endoluminal grafting for exclusion of abdominal aortic aneurysms. The beauty and the beast.

    PubMed Central

    Diethrich, E B

    1998-01-01

    The exclusion of abdominal aortic aneurysms with endoluminal grafts has generated a great deal of interest since the early 1990s, and many centers are currently evaluating the procedure and comparing it to classic surgical exclusion. Although endoluminal grafting procedures show promise, development and clinical testing of devices is a time-consuming process that is influenced greatly by the regulatory climate in the country where the clinical trials take place. Nevertheless, a number of devices are currently under study, and the advantages of 2nd- and 3rd-generation technology are reflected in reduced rates of complications such as endoleaks and thrombosis. Further study will be required to perfect these devices and observe their long-term success in the exclusion of abdominal aortic aneurysms. Images PMID:9566057

  20. A Case of Infective Abdominal Aortic Aneurysm due to Haemophilus influenzae Type B

    PubMed Central

    Sato, Toshimitsu; Kobayashi, Masayoshi

    2012-01-01

    Infective abdominal aortic aneurysm (IAAA) is relatively rare, but a case which is caused by Haemophilus influenzae type B is very rare. We experienced one IAAA case due to H. influenzae type B. The patient was 69-year-old man presenting with severe abdominal and back pain and elevated C-reactive protein (CRP), as inflammatory marker. The patient was found to have saccular aneurysm infrarenal aorta on computed tomography scanning. First, we started to treat him with antibiotic agent and second, we operated him at day 8 after admission with expanded polytetrafluoroethylene graft. Revascularization was made in situ reconstruction. As the result of culture with aneurysm wall, we found that the cause of this aneurysm was the infection of H. influenzae type B. As far as we know, this bacterium is scarcely reported as the cause of infective aortic aneurysms. We reported this IAAA case with the review of the English literature. PMID:23997558

  1. A Case of Infective Abdominal Aortic Aneurysm due to Haemophilus influenzae Type B.

    PubMed

    Sato, Toshimitsu; Kobayashi, Masayoshi

    2012-09-01

    Infective abdominal aortic aneurysm (IAAA) is relatively rare, but a case which is caused by Haemophilus influenzae type B is very rare. We experienced one IAAA case due to H. influenzae type B. The patient was 69-year-old man presenting with severe abdominal and back pain and elevated C-reactive protein (CRP), as inflammatory marker. The patient was found to have saccular aneurysm infrarenal aorta on computed tomography scanning. First, we started to treat him with antibiotic agent and second, we operated him at day 8 after admission with expanded polytetrafluoroethylene graft. Revascularization was made in situ reconstruction. As the result of culture with aneurysm wall, we found that the cause of this aneurysm was the infection of H. influenzae type B. As far as we know, this bacterium is scarcely reported as the cause of infective aortic aneurysms. We reported this IAAA case with the review of the English literature.

  2. Hypoperfusion of the Adventitial Vasa Vasorum Develops an Abdominal Aortic Aneurysm.

    PubMed

    Tanaka, Hiroki; Zaima, Nobuhiro; Sasaki, Takeshi; Sano, Masaki; Yamamoto, Naoto; Saito, Takaaki; Inuzuka, Kazunori; Hayasaka, Takahiro; Goto-Inoue, Naoko; Sugiura, Yuki; Sato, Kohji; Kugo, Hirona; Moriyama, Tatsuya; Konno, Hiroyuki; Setou, Mitsutoshi; Unno, Naoki

    2015-01-01

    The aortic wall is perfused by the adventitial vasa vasorum (VV). Tissue hypoxia has previously been observed as a manifestation of enlarged abdominal aortic aneurysms (AAAs). We sought to determine whether hypoperfusion of the adventitial VV could develop AAAs. We created a novel animal model of adventitial VV hypoperfusion with a combination of a polyurethane catheter insertion and a suture ligation of the infrarenal abdominal aorta in rats. VV hypoperfusion caused tissue hypoxia and developed infrarenal AAA, which had similar morphological and pathological characteristics to human AAA. In human AAA tissue, the adventitial VV were stenotic in both small AAAs (30-49 mm in diameter) and in large AAAs (> 50 mm in diameter), with the sac tissue in these AAAs being ischemic and hypoxic. These results indicate that hypoperfusion of adventitial VV has critical effects on the development of infrarenal AAA.

  3. Characterization of the transport topology in patient-specific abdominal aortic aneurysm models

    NASA Astrophysics Data System (ADS)

    Arzani, Amirhossein; Shadden, Shawn C.

    2012-08-01

    Abdominal aortic aneurysm (AAA) is characterized by disturbed blood flow patterns that are hypothesized to contribute to disease progression. The transport topology in six patient-specific abdominal aortic aneurysms was studied. Velocity data were obtained by image-based computational fluid dynamics modeling, with magnetic resonance imaging providing the necessary simulation parameters. Finite-time Lyapunov exponent (FTLE) fields were computed from the velocity data, and used to identify Lagrangian coherent structures (LCS). The combination of FTLE fields and LCS was used to characterize topological flow features such as separation zones, vortex transport, mixing regions, and flow impingement. These measures offer a novel perspective into AAA flow. It was observed that all aneurysms exhibited coherent vortex formation at the proximal segment of the aneurysm. The evolution of the systolic vortex strongly influences the flow topology in the aneurysm. It was difficult to predict the vortex dynamics from the aneurysm morphology, motivating the application of image-based flow modeling.

  4. Automatic segmentation and co-registration of gated CT angiography datasets: measuring abdominal aortic pulsatility

    NASA Astrophysics Data System (ADS)

    Wentz, Robert; Manduca, Armando; Fletcher, J. G.; Siddiki, Hassan; Shields, Raymond C.; Vrtiska, Terri; Spencer, Garrett; Primak, Andrew N.; Zhang, Jie; Nielson, Theresa; McCollough, Cynthia; Yu, Lifeng

    2007-03-01

    Purpose: To develop robust, novel segmentation and co-registration software to analyze temporally overlapping CT angiography datasets, with an aim to permit automated measurement of regional aortic pulsatility in patients with abdominal aortic aneurysms. Methods: We perform retrospective gated CT angiography in patients with abdominal aortic aneurysms. Multiple, temporally overlapping, time-resolved CT angiography datasets are reconstructed over the cardiac cycle, with aortic segmentation performed using a priori anatomic assumptions for the aorta and heart. Visual quality assessment is performed following automatic segmentation with manual editing. Following subsequent centerline generation, centerlines are cross-registered across phases, with internal validation of co-registration performed by examining registration at the regions of greatest diameter change (i.e. when the second derivative is maximal). Results: We have performed gated CT angiography in 60 patients. Automatic seed placement is successful in 79% of datasets, requiring either no editing (70%) or minimal editing (less than 1 minute; 12%). Causes of error include segmentation into adjacent, high-attenuating, nonvascular tissues; small segmentation errors associated with calcified plaque; and segmentation of non-renal, small paralumbar arteries. Internal validation of cross-registration demonstrates appropriate registration in our patient population. In general, we observed that aortic pulsatility can vary along the course of the abdominal aorta. Pulsation can also vary within an aneurysm as well as between aneurysms, but the clinical significance of these findings remain unknown. Conclusions: Visualization of large vessel pulsatility is possible using ECG-gated CT angiography, partial scan reconstruction, automatic segmentation, centerline generation, and coregistration of temporally resolved datasets.

  5. Inferior vena cava occlusion secondary to an inflammatory abdominal aortic aneurysm.

    PubMed

    Yoshizaki, Tomoya; Tabuchi, Noriyuki; Makita, Satoru

    2007-02-01

    Inflammatory abdominal aortic aneurysms (IAAAs) represent 3% to 10% of all AAAs. However, inferior vena cava occlusion secondary to an IAAA is rarely reported. We report a case of inferior vena cava occlusion secondary to an IAAA presenting deep venous thrombosis. As it is crucial to avoid pulmonary embolism and excessive blood loss during an operation, we pre-operatively implanted a venous filter and minimized intra-operative dissection that allowed successful operative repair.

  6. Mycotic Abdominal Aortic Aneurysm Secondary to Septic Embolism of a Thoracic Aorta Graft Infection.

    PubMed

    Blanco Amil, Carla Lorena; Vidal Rey, Jorge; López Arquillo, Irene; Pérez Rodríguez, María Teresa; Encisa de Sá, José Manuel

    2016-05-01

    Mycotic aneurysms account for 1% of abdominal aortic aneurysms. There are very few cases published that describe the formation of mycotic aneurysms after septic embolism due to graft infection. We present the first case to our knowledge to be described in the literature of a mycotic aneurysm caused by septic embolism derived from a thoracic aorta graft infection, treated with conventional surgery leading to a successful outcome and evolution.

  7. [Percutaneous exclusion of traumatic abdominal aortic pseudoaneurysm from a brachial approach].

    PubMed

    Gamboa, Ricardo; Ríos-Méndez, Raúl E; Solernó, Raúl; Giachello, Federico; Videla-Lynch, Ángeles; Sarmiento, Ricardo A

    2012-01-01

    Abdominal aortic pseudoaneurysm (AAP) is a rare lesion, although traumatic aortic injury is described as one of the main causes; both the rupture as the surgical treatment of the defect has high morbidity and mortality. Therefore, endovascular treatment either by chemical embolization or exclusion of defect with devices has emerged as an alternative treatment. However, there are risks such as occlusion of visceral vessels near the neck of the defect, embolization material or aortic rupture. Therefore, the choice of material and method of approach should be planned carefully in each case. We report a patient who ten years after abdominal wound firearm was diagnosed with AAP 17 x 13 cm, with short neck originated close to the ostium of the celiac trunk at an acute angle with the aortic axis. We perform the exclusion of the defect with a device designed for closing atrial septal defect from the left brachial access due to the angulation of the neck defect. There were no complications. At 72 hours was granted discharge. A month later, CT scan control showed the false aneurysm of equal size and no residual flow. The monitoring to date is five months and the patient remained asymptomatic.

  8. Family history of atherosclerotic vascular disease is associated with the presence of abdominal aortic aneurysm.

    PubMed

    Ye, Zi; Bailey, Kent R; Austin, Erin; Kullo, Iftikhar J

    2016-02-01

    We investigated whether family history (FHx) of atherosclerotic cardiovascular disease (ASCVD) was associated with presence of abdominal aortic aneurysm (AAA). The study cohort comprised of 696 patients with AAA (70±8 years, 84% men) and 2686 controls (68±10 years, 61% men) recruited from noninvasive vascular and stress electrocardiogram (ECG) laboratories at Mayo Clinic. AAA was defined as a transverse diameter of abdominal aorta ⩾ 3 cm or history of AAA repair. Controls were not known to have AAA. FHx was defined as having at least one first-degree relative with aortic aneurysm or with onset of ASCVD (coronary, cerebral or peripheral artery disease) before age 65 years. FHx of aortic aneurysm or ASCVD were each associated with presence of AAA after adjustment for age, sex, conventional risk factors and ASCVD: adjusted odds ratios (OR; 95% confidence interval): 2.17 (1.66-2.83, p < 0.01) and 1.31 (1.08-1.59, p < 0.01), respectively. FHx of ASCVD remained associated with AAA after additional adjustment for FHx of aortic aneurysm: adjusted OR: 1.27 (1.05-1.55, p = 0.01). FHx of ASCVD in multiple arterial locations was associated with higher odds of having AAA: the adjusted odds were 1.23 times higher for each additionally affected arterial location reported in the FHx (1.08-1.40, p = 0.01). Our results suggest both unique and shared environmental and genetic factors mediating susceptibility to AAA and ASCVD.

  9. Inflammatory abdominal aortic aneurysms: a disease entity? Histological analysis of 60 cases of inflammatory aortic aneurysms of unknown aetiology.

    PubMed

    Leu, H J

    1990-01-01

    Sixty inflammatory aortic aneurysms of unknown aetiology were examined by serial sections. The histological findings failed to reveal significant differences in either thoracic or abdominal aneurysms with or without marked adventitial fibrosis. Their identical morphology does not favour the existence of a special disease entity of so-called inflammatory abdominal aortic aneurysms (IAAA). Absence or existence of giant cells of any type, occurrence of plasma cells, eosinophils, granulomas, fibrinoid necrosis and adventitial fibrotic thickening cannot be considered as variables which help in differentiation. IAAA are characterized by a marked predominance of male patients and a rather benign clinical course. They usually affect the age group around 60 years. They are not rare and do not seem to be restricted to certain races. Their aetiology, like that of the cases affecting the thoracic aorta (Takayasu's disease, non-specific aortitis) remains unknown, although autoimmune diseases, the retroperitoneal fibrosis of Ormond and arteriosclerosis may be related. However, on the basis of the present evidence we cannot consider them to be one of these diseases. There are no morphological findings which would justify the separation of IAAA from Takaysu's disease.

  10. Open versus endovascular stent graft repair for abdominal aortic aneurysms: an historical view.

    PubMed

    Rutherford, Robert B

    2012-03-01

    Development of endovascular abdominal aortic aneurysms repair (EVAR), now in its 4th decade, has involved at least 16 different devices, not counting major modifications of some, only 4 of which have emerged from clinical trials and gained US Food and Drug Administration approval. The main impetus behind EVAR has been its potential for significantly reducing procedural mortality and morbidity, but it was also expected to speed recovery and reduce costs through decreased use of hospital resources. At the outset, EVAR was touted as a better alternative to OPEN in high-risk patients with large abdominal aortic aneurysms, and to "watchful waiting" (periodic ultrasound surveillance) for those with small abdominal aortic aneurysms. This new technology has evoked a mixed response with enthusiasts and detractors debating its pros and cons. Bias and conflict of interest exist on both sides. This review will attempt to present a balanced review of the development and current status of this controversial competition between EVAR and OPEN, comparing them in terms of the following key considerations: mortality and morbidity, complications, failure modes and durability, and costs.

  11. Histological characteristics of the abdominal aortic wall in patients with vascular chronic Q fever

    PubMed Central

    Hagenaars, Julia C J P; Koning, Olivier H J; van den Haak, Ronald F F; Verhoeven, Bart A N; Renders, Nicole H M; Hermans, Mirjam H A; Wever, Peter C; van Suylen, Robert Jan

    2014-01-01

    The aim of this study was to describe specific histological findings of the Coxiella burnetii-infected aneurysmal abdominal aortic wall. Tissue samples of the aneurysmal abdominal aortic wall from seven patients with chronic Q fever and 15 patients without evidence of Q fever infection were analysed and compared. Chronic Q fever was diagnosed using serology and tissue PCR analysis. Histological sections were stained using haematoxylin and eosin staining, Elastica van Gieson staining and immunohistochemical staining for macrophages (CD68), T lymphocytes (CD3), T lymphocyte subsets (CD4 and CD8) and B lymphocytes (CD20). Samples were scored by one pathologist, blinded for Q fever status, using a standard score form. Seven tissue samples from patients with chronic Q fever and 15 tissue samples from patients without Q fever were collected. Four of seven chronic Q fever samples showed a necrotizing granulomatous response of the vascular wall, which was characterized by necrotic core of the arteriosclerotic plaque (P = 0.005) and a presence of high numbers of macrophages in the adventitia (P = 0.007) distributed in typical palisading formation (P = 0.005) and surrounded by the presence of high numbers of T lymphocytes located diffusely in media and adventitia. Necrotizing granulomas are a histological finding in the C. burnetii-infected aneurysmal abdominal aortic wall. Chronic Q fever should be included in the list of infectious diseases with necrotizing granulomatous response, such as tuberculosis, cat scratch disease and syphilis. PMID:24953727

  12. Mega aorta syndrome: a case of thoracic and abdominal aortic aneurysm.

    PubMed

    Wu, William C; Mitchell, Christopher A; Linklater, Derek

    2010-07-01

    An 83-year-old woman presented to the emergency department (ED) via emergency medical services with the chief complaint of "strokelike symptoms." Physical examination revealed altered mental status, tachycardia, hypotension, and a large nonpulsatile periumbilical mass. Bedside ultrasound revealed a 9-cm abdominal aortic aneurysm with absent central flow. Computed tomography scan demonstrated diffuse thoracic and abdominal aortic dilation with rupture into the mediastinum along with left hemothorax. Repeat beside ultrasound demonstrated abdominal aortic aneurysm rupture not seen on the computed tomography scan. Despite aggressive resuscitation, the patient developed bradycardia, which devolved into pulseless electric activity cardiac arrest. She was unable to be resuscitated. The patient's diffuse aneurysmal dilation places her into the small category of patients with a disease entity known as mega aorta syndrome (MAS). Mega aorta syndrome is defined as aneurysmal dilation of the aorta to greater than 6 cm in diameter. Although not in our case, most cases of MAS are symptomatic before catastrophic presentation. The disease progression for these patients is slow and occurs over years. When this disease is recognized early, a surgery known as the elephant trunk procedure can be performed. This operation replaces the entire aorta in multiple stages. This gives the emergency physician a critical role in the diagnosis and outcome of these patients because they may come through the ED for an unrelated complaint early in the disease process. This case report illustrates an advanced case of MAS.

  13. Are we cross-matching too much blood for elective open abdominal aortic aneurysm repair?

    PubMed Central

    Lowe, Emily; Quarmby, John

    2017-01-01

    Objectives: This study aims to identify current blood transfusion requirements in elective open abdominal aortic aneurysm repair and to compare this to an existing maximum surgical blood order schedule. Methods: We retrospectively identified patients who underwent elective open abdominal aortic aneurysm repair over a 40-month period in our institution. Pre-operative number of units cross-matched and the number of units actually transfused were identified. The cross-match to transfusion ratio was then calculated. Results: Blood transfusion at any time post-operatively was required in 23 (48.9%) cases. Patients needing an intra-operative blood transfusion had a median of 2 units. Of the pre-operative cross-matched units (123), only 43 were used, giving a cross-match to transfusion ratio of 2.86. Conclusion: Our current maximum surgical blood order schedule is poorly followed and a cross-match to transfusion ratio of 2.86 indicates we are cross-matching too many units for elective open abdominal aortic aneurysm repair. A carefully considered individualised management of blood products, with the requirement of at least a valid group and save sample, may be more appropriate. PMID:28228951

  14. [Early detection of abdominal aortic aneurysm in risk population].

    PubMed

    Enríquez-Vega, María Elizabeth; Solorio-Rosete, Hugo Francisco; Cossío-Zazueta, Alfonso; Bizueto-Rosas, Héctor; Cruz-Castillo, Juan Ernesto; Iturburu-Enríquez, Alessandra

    2015-01-01

    Introducción: aneurisma es el incremento del diámetro de una arteria > 50 %; los más frecuentes son los aneurismas de la aorta abdominal (AAA). La ecografía abdominal es el estudio de escrutinio para su diagnóstico. La detección oportuna del AAA en población de riesgo disminuye la morbimortalidad. El objetivo fue estimar la frecuencia de AAA en pacientes mayores de 65 años.Métodos: Se realizó un estudio transversal entre junio y octubre del 2012 en pacientes de ambos sexos mayores de 65 años que cubrieron los criterios de selección. Se les practicó ultrasonidoDoppler dúplex y se midió el diámetro anteroposterior de la aorta abdominal infrarrenal, se definió como AAA a una aorta abdominal con un diámetro mayor a 3 cm. Se empleó estadística descriptiva y regresión logística para factores de riesgo.Resultados: se incluyeron 144 pacientes, edad media (72.7 ± 6.7), el 95.1 % sexo masculino. El 13 % continuaban fumando. En 127 el diámetro de la aorta fue normal. Se detectaron 10 pacientes con AAA, todos del sexo masculino, el diámetro de los aneurismas identificados variaron de 3.2 a 7.11 cm, el diámetro promedio de 3 - 4 cm (n = 5). Solo el tabaquismo activo fue un factor predictivo significativo para AAA.Conclusión: Se demostró frecuencia significativa de AAA no detectada en masculinos mayores de 65 años, el tabaquismo fue el factor de riesgo más importante.

  15. Endovascular repair of inflammatory abdominal aortic aneurysms: a valuable alternative?--Case report and review of literature.

    PubMed

    Ruppert, Volker; Verrel, Frauke; Kellner, Wolfgang; Brandl, Thomas; Reininger, Cornelia B; Steckmeier, Bernd

    2004-05-01

    While endovascular repair (ER) has become a routine procedure in the treatment of arteriosclerotic abdominal aortic aneurysms with a suitable configuration, only rare reports of interventional treatment of inflammatory aortic abdominal aneurysms (IAAA) exist. We present a case study of a male patient with IAAA, who presented with inflammatory thickening involving the entire circumference of the aortic vessel wall. The MRI performed 8 months after successful ER demonstrated complete regression of vessel wall induration. A patient with the appropriate anatomical configuration of IAAA should benefit from the lower morbidity and mortality of endovascular aneurysm repair (EVAR). In our view, EVAR is preferable to open surgical repair in the specific situation of IAAA.

  16. Hemodynamic Study of Flow Remodeling Stent Graft for the Treatment of Highly Angulated Abdominal Aortic Aneurysm

    PubMed Central

    Yeow, Siang Lin; Leo, Hwa Liang

    2016-01-01

    This study investigates the effect of a novel flow remodeling stent graft (FRSG) on the hemodynamic characteristics in highly angulated abdominal aortic aneurysm based on computational fluid dynamics (CFD) approach. An idealized aortic aneurysm with varying aortic neck angulations was constructed and CFD simulations were performed on nonstented models and stented models with FRSG. The influence of FRSG intervention on the hemodynamic performance is analyzed and compared in terms of flow patterns, wall shear stress (WSS), and pressure distribution in the aneurysm. The findings showed that aortic neck angulations significantly influence the velocity flow field in nonstented models, with larger angulations shifting the mainstream blood flow towards the center of the aorta. By introducing FRSG treatment into the aneurysm, erratic flow recirculation pattern in the aneurysm sac diminishes while the average velocity magnitude in the aneurysm sac was reduced in the range of 39% to 53%. FRSG intervention protects the aneurysm against the impacts of high velocity concentrated flow and decreases wall shear stress by more than 50%. The simulation results highlighted that FRSG may effectively treat aneurysm with high aortic neck angulations via the mechanism of promoting thrombus formation and subsequently led to the resorption of the aneurysm. PMID:27247612

  17. Influence of IABP-Induced Abdominal Occlusions on Aortic Hemodynamics: A Patient-Specific Computational Evaluation.

    PubMed

    Caruso, Maria Vittoria; Renzulli, Attilio; Fragomeni, Gionata

    Intraaortic balloon pump (IABP) is used as temporary mechanical assistance in case of cardiovascular diseases, even if different hemodynamic problems and, thus, clinical complications may happen, such as the decrease of visceral perfusion. A computational fluid dynamic (CFD) study was carried out to investigate the effects of different IABP-induced abdominal occlusions on patient-specific aortic flow. Two possible sizes (25 and 34 cm) and two locations (2 and 3 cm) of the balloon were compared, modeling four abdominal occlusions and numerically reproducing IAB inflation/deflation behavior. The results highlighted that the perfusion in renal, mesenteric, and iliac arteries decreases when the abdominal occlusion increases with balloon inflation. The study illustrates also how the balloon size affects the flow in aorta vessels in both locations, and that the positioning is of little relevance for the 34 cm balloon, whereas it influences the aortic flow very much in case of 25 cm IAB. This analysis demonstrates how the IAB-induced occlusion may vary the abdominal circulation; therefore, the correct size and positioning are emphasized for patient's outcome.

  18. [Ultrasound diagnosis of an abdominal aortic aneurysm in a 52 year old woman].

    PubMed

    Romero-Hernández, Juan José; Lozano-Corona, Marco Antonio; Díaz-Méndez, Macrina; Aspeitia-León, Jorge Alejandro; Hernández-Díaz, Víctor; Magaña-Cabrera, Daniel

    2012-01-01

    The abdominal aortic aneurysm (AAA) is defined as increasing the diameter of the aorta in more than 50 % of its original size and the infra-renal location is the most common (90 %). AAA disease mainly affects older men and white smokers, and has a male: female ratio of 4:1, as well the diagnosis is rare in women under age 55. Aneurysm rupture is the most common complication and cause of death in the general population, its etiology is unclear, but is commonly associated with atherosclerosis. The AAA do not exhibit rupture and it is usually asymptomatic diagnosed incidentally, however, as the aneurysm grows, appears symptoms such as back pain, abdominal or groin pain, well as palpation of a pulse mass on umbilical and supra-umbilical region. Imaging study such as ultrasound and CT scan are the mainstay of diagnosis. We present a case of 52 years old patient with no history related to the diagnosis, who presented sudden and severe abdominal pain. She was admitted to the emergency room with a diagnosis of acute cholecystitis vs. acute pancreatitis. After ultrasound and CT studies, the diagnosis was a complicated abdominal aortic aneurysm.

  19. Novel risk predictor for thrombus deposition in abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Nestola, M. G. C.; Gizzi, A.; Cherubini, C.; Filippi, S.; Succi, S.

    2015-10-01

    The identification of the basic mechanisms responsible for cardiovascular diseases stands as one of the most challenging problems in modern medical research including various mechanisms which encompass a broad spectrum of space and time scales. Major implications for clinical practice and pre-emptive medicine rely on the onset and development of intraluminal thrombus in which effective clinical therapies require synthetic risk predictors/indicators capable of informing real-time decision-making protocols. In the present contribution, two novel hemodynamics synthetic indicators, based on a three-band decomposition (TBD) of the shear stress signal, are introduced. Extensive fluid-structure computer simulations of patient-specific scenarios confirm the enhanced risk-prediction capabilities of the TBD indicators. In particular, they permit a quantitative and accurate localization of the most likely thrombus deposition in realistic aortic geometries, where previous indicators would predict healthy operation. The proposed methodology is also shown to provide additional information and discrimination criteria on other factors of major clinical relevance, such as the size of the aneurysm.

  20. CT evaluation of complications of abdominal aortic surgery

    SciTech Connect

    Mark, A.; Moss, A.A.; Lusby, R.; Kaiser, J.A.

    1982-11-01

    The authors conducted a retrospective analysis of the CT findings in 29 consecutive patients being studied to detect complications of aortofemoral bypass surgery. Presenting symptoms included fever in 22 (76%), gastrointestinal bleeding in 2 (7%), a pulsating mass in 3 (10%), jaundice in 1 (3%), and back pain in 1 (3%). The complications observed most frequently were groin infection in 7 (24%), abdominal perigraft abscess in 11 (38%), pseudoaneurysm in 6 (21%), aorto-enteric fistula in 3 (10%), and lymphocystic hematoma in 3 (10%). There were no false negatives, and overall accuracy and sensitivity of CT in detecting complications was 100%. The authors recommend that CT be performed prior to angiography or surgery whenever an abscess, pseudoaneurysm, or aorto-enteric fistula is suspected.

  1. Relation between low serum cholesteryl-ester transfer activity and abdominal aortic calcification in normolipidemic elderly subjects.

    PubMed

    Miyashita, Y; Morimoto, S; Fukuo, K; Masuyama, T; Yasuda, O; Koh, E; Tamatani, M; Nakahashi, T; Ogihara, T

    1993-01-01

    We studied the relation between cholesteryl-ester transfer activity (CETA) and abdominal aortic calcification in elderly subjects. Compared with 10 young healthy subjects (mean +/- S.D. age, 27 +/-2 years) and to 26 elderly subjects without abdominal aortic calcification (79 +/- 7 years), 16 elderly patients with abdominal aortic calcification (82 +/- 6 years) had significantly lower levels of serum CETA. However, there were no differences in the levels of serum lipids and apolipoproteins, including total cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol and apolipoproteins A-I, A-II, B, C-II and E, between the two elderly groups. When the two groups of elderly subjects were considered together, the level of serum CETA did not correlate significantly with any lipids and apolipoproteins. These results provide evidence that CETA may prevent the development of aortic calcification in normolipidemic elderly people.

  2. Enhanced production of the chemotactic cytokines interleukin-8 and monocyte chemoattractant protein-1 in human abdominal aortic aneurysms.

    PubMed Central

    Koch, A. E.; Kunkel, S. L.; Pearce, W. H.; Shah, M. R.; Parikh, D.; Evanoff, H. L.; Haines, G. K.; Burdick, M. D.; Strieter, R. M.

    1993-01-01

    Inflammatory leukocytes play a central role in the pathogenesis of human atherosclerotic disease, from early atherogenesis to the late stages of atherosclerosis, such as aneurysm formation. We have shown previously that human abdominal aortic aneurysms are characterized by the presence of numerous chronic inflammatory cells throughout the vessel wall (Am J Pathol 1990, 137: 1199-1213). The signals that attract lymphocytes and monocytes into the aortic wall in aneurysmal disease remain to be precisely defined. We have studied the production of the chemotactic cytokines interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) by aortic tissues obtained from 47 subjects. We compared the antigenic production of these cytokines by explants of: 1) human abdominal aneurysmal tissue, 2) occlusive (atherosclerotic) aortas, and 3) normal aortas. IL-8, which is chemotactic for neutrophils, lymphocytes, and endothelial cells was liberated in greater quantities by abdominal aortic aneurysms than by occlusive or normal aortas. Using immunohistochemistry, macrophages, and to a lesser degree endothelial cells, were found to be positive for the expression of antigenic IL-8. Similarly, MCP-1, a potent chemotactic cytokine for monocytes/macrophages, was released by explants from abdominal aortic aneurysms in greater quantities than by explants from occlusive or normal aortas. Using immunohistochemistry, the predominant MCP-1 antigen-positive cells were macrophages and to a lesser extent smooth muscle cells. Our results indicate that human abdominal aortic aneurysms produce IL-8 and MCP-1, both of which may serve to recruit additional inflammatory cells into the abdominal aortic wall, hence perpetuating the inflammatory reaction that may result in the pathology of vessel wall destruction and aortic aneurysm formation. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:8494046

  3. Endovascular treatment of ruptured abdominal aortic aneurysm with aortocaval fistula based on aortic and inferior vena cava stent-graft placement.

    PubMed

    Silveira, Pierre Galvagni; Cunha, Josué Rafael Ferreira; Lima, Guilherme Baumgardt Barbosa; Franklin, Rafael Narciso; Bortoluzzi, Cristiano Torres; Galego, Gilberto do Nascimento

    2014-11-01

    A ruptured abdominal aortic aneurysm (RAAA), complicated by an aortocaval fistula (ACF), is usually associated with high morbidity and mortality during open operative repair. We report a case of endovascular treatment of an RAAA with ACF. After accessing both common femoral arteries, a bifurcated aortic stent graft was placed. Subsequently, we accessed the fistula from the right femoral vein and a cava vein angiography showed a persistent massive flow from the cava to the excluded aneurysm sac. We proceeded by covering the fistula with an Excluder aortic stent-graft cuff to prevent pressurization of the aneurysm sac and secondary endoleaks. This procedure is feasible and may reduce the chances of posterior endoleaks.

  4. Surgical treatment of inflammatory abdominal aortic aneurysms: Outcome and predictors analysis

    PubMed Central

    Nuellari, Edmond; Esposito, Giampiero; Kuci, Saimir; Kapedani, Edmond

    2014-01-01

    Objectives The aim of this study is to report our experience on the postoperative outcome of surgical treatment of inflammatory abdominal aortic aneurysm (IAAA). Materials and Methods Between 1997–2014, 35 patients with IAAA underwent surgery. The mean age was 63 ± 18 years. Chronic renal failure was identified in 11 (31.4%) patients and confirmed ischemic heart disease in 15 (43%) patients. The mean aortic aneurysm diameter was 68 ± 25 mm. The abdominal aorta was clamped above the renal arteries in 6 (17%) patients. Results The hospital mortality was 5.7% (2 patients). Three patients developed an aortic pseudoaneurysm and underwent a redo operation. Another patient developed a femoral anastomotic pseudoaneurysm 7 years after operation and he was treated surgically. The actuarial free-reoperation actuarial survival at 1, 5 and 7 years was 94%, 62% and 50%, respectively. The Cox model revealed the delta erythrocyte sedimentation rate (p = 0.002), ischemic heart disease (p = 0.006) and renal failure (p = 0.036) as strong predictors for poor overall outcome. Conclusion Early postoperative outcome in terms of mortality and morbidity seems acceptable, however, patients with IAAA have an increased risk for reoperation due to pseudonaneurysm formation. Strong predictors for poor overall outcome seem to be the elevated erythrocyte sedimentation rate, ischemic heart disease and chronic renal failure. PMID:25243075

  5. Surgical Treatment of Inflammatory Abdominal Aortic Aneurysms: Outcome and Predictors Analysis

    PubMed Central

    Nuellari, Edmond; Prifti, Edvin; Esposito, Giampiero; Kapedani, Edmond

    2014-01-01

    Objectives: The aim of this study is to report our experience on the postoperative outcome of surgical treatment of inflammatory abdominal aortic aneurysm (IAAA). Materials and Methods: Between 1997-2014, 35 patients with IAAA underwent surgery. The mean age was 63+/-18years. Chronic renal failure was identified in 11(31.4%)patients and confirmed ischemic heart disease in 15(43%)patients. The mean aortic aneurysm diameter was 68+/-25mm. The abdominal aorta was clamped above the renal arteries in 6 (17%) patients. Results: The hospital mortality was 5.7% (2 patients). Three patients developed an aortic pseudoaneurysm and underwent a redo operation. Another patient developed a femoral anastomotic pseudoaneurysm 7 years after operation and he was treated surgically. The actuarial free-reoperation actuarial survival at 1, 5 and 7 years was 94%, 62% and 50% respectively. The Cox model revealed the delta ESR (p=0.002), ischemic heart disease (p=0.006) and renal failure (p=0.036) as strong predictors for poor overall outcome. Conclusion: Early postoperative outcome in terms of mortality and morbidity seems acceptable, however patients with IAAA have an increased risk for reoperation due to pseudonaneurysm formation. Strong predictors for poor overall outcome seems to be the elevated erythrocyte sedimentation rate, ischemic heart disease and chronic renal failure. PMID:25568545

  6. Automated Delineation of Vessel Wall and Thrombus Boundaries of Abdominal Aortic Aneurysms Using Multispectral MR Images

    PubMed Central

    Rodriguez-Vila, B.; Tarjuelo-Gutierrez, J.; Sánchez-González, P.; Verbrugghe, P.; Fourneau, I.; Maleux, G.; Herijgers, P.; Gomez, E. J.

    2015-01-01

    A correct patient-specific identification of the abdominal aortic aneurysm is useful for both diagnosis and treatment stages, as it locates the disease and represents its geometry. The actual thickness and shape of the arterial wall and the intraluminal thrombus are of great importance when predicting the rupture of the abdominal aortic aneurysms. The authors describe a novel method for delineating both the internal and external contours of the aortic wall, which allows distinguishing between vessel wall and intraluminal thrombus. The method is based on active shape model and texture statistical information. The method was validated with eight MR patient studies. There was high correspondence between automatic and manual measurements for the vessel wall area. Resulting segmented images presented a mean Dice coefficient with respect to manual segmentations of 0.88 and a mean modified Hausdorff distance of 1.14 mm for the internal face and 0.86 and 1.33 mm for the external face of the arterial wall. Preliminary results of the segmentation show high correspondence between automatic and manual measurements for the vessel wall and thrombus areas. However, since the dataset is small the conclusions cannot be generalized. PMID:26236390

  7. Extended use of endovascular aneurysm sealing for ruptured abdominal aortic aneurysms.

    PubMed

    Böckler, Dittmar; Holden, Andrew; Krievins, Dainis; de Vries, Jean-Paul P M; Peters, Andreas S; Geisbüsch, Philipp; Reijnen, Michel

    2016-09-01

    Endovascular repair of abdominal aortic aneurysms (EVAR) is now an established treatment modality for suitable patients presenting with aneurysm rupture. EVAR for ruptured aneurysms reduces transfusion, mechanical ventilation, intensive care. and hospital stay when compared with open surgery. In the emergency setting, however, EVAR is limited by low applicability due to adverse clinical or anatomical characteristics and increased need for reintervention. In addition, ongoing bleeding from aortic side branches post-EVAR can cause hemodynamic instability, larger hematomas, and abdominal compartment syndrome. Endovascular aneurysm sealing, based on polymer filling of the aneurysm, has the potential to overcome some of the limitations of EVAR for ruptured aneurysms and to improve outcomes. Recent literature suggests that endovascular aneurysm sealing can be performed with early mortality similar to that of EVAR for ruptured aortic aneurysms, but experience is limited to a few centers and a small number of patients. The addition of chimney grafts can increase the applicability of endovascular aneurysm sealing in order to treat short-neck and juxtarenal aneurysms as an alternative to fenestrated endografts. Further evaluation of the technique, with larger longitudinal studies, is necessary before advocating wider implementation of endovascular aneurysm sealing in the emergency setting.

  8. [Ultrasound screening of abdominal aortic aneurysm: Lessons from Vesale 2013].

    PubMed

    Laroche, J P; Becker, F; Baud, J M; Miserey, G; Jaussent, A; Picot, M C; Bura-Rivière, A; Quéré, I

    2015-12-01

    Although aneurysm of the abdominal infra-renal aorta (AAA) meets criteria warranting B mode ultrasound screening, the advantages of mass screening versus selective targeted opportunistic screening remain a subject of debate. In France, the French Society of Vascular Medicine (SFMV) and the Health Authority (HAS) published recommendations for targeted opportunistic screening in 2006 and 2013 respectively. The SFMV held a mainstream communication day on November 21, 2013 in France involving participants from metropolitan France and overseas departments that led to a proposal for free AAA ultrasound screening: the Vesalius operation. Being a consumer operation, the selection criteria were limited to age (men and women between 60 and 75 years); the age limit was lowered to 50 years in case of direct family history of AAA. More than 7000 people (as many women as men) were screened in 83 centers with a 1.70% prevalence of AAA in the age-based target population (3.12% for men, 0.27% for women). The median diameter of detected AAA was 33 mm (range 20 to 74 mm). The prevalence of AAA was 1.7% in this population. Vesalius data are consistent with those of the literature both in terms of prevalence and for cardiovascular risk factors with the important role of smoking. Lessons from Vesalius to take into consideration are: screening is warranted in men 60 years and over, especially smokers, and in female smokers. Screening beyond 75 years should be discussed. Given the importance of screening, the SFMV set up a year of national screening for AAA (Vesalius operation 2014/2015) in order to increase public and physician awareness about AAA detection, therapeutic management, and monitoring. AAA is a serious, common, disease that kills 6000 people each year. The goal of screening is cost-effective reduction in the death toll.

  9. Atmospheric Pressure Changes Are Associated with Type A Acute Aortic Dissections and Spontaneous Abdominal Aortic Aneurysm Rupture in Tuzla Canton

    PubMed Central

    Krdzalic, Alisa; Rifatbegovic, Zijah; Krdzalic, Goran; Jahic, Elmir; Adam, Visnja Nesek; Golic, Darko

    2014-01-01

    Aim: The aim of this study was to investigate a relationship between seasonal variation and incidence of type A acute aortic dissection (AAD) and spontaneous abdominal aneurysm rupture (rAAA) in Canton Tuzla, Bosnia and Herzegovina. Patients and methods: A total of 81 cases, 41 AAD and 40 of ruptured AAA were identified from one center over a 6-year, from 2008 till 2013. In 2012 were admitted (45.6% or 36 patients). Results: Seasonal analysis showed that 19(23.4%) patients were admitted in spring, 15(18.5) in summer, 26(32%) in autumn and 21(25.9) in winter. The most frequent period was autumn/winter with 47 or 58% patients. A causal link between atmospheric pressure (AP) and incidence of rAAA and AAD on seasonal and monthly basis was found. PMID:25568523

  10. Endovascular Treatment of Infrarenal Abdominal Aortic Lesions With or Without Common Iliac Artery Involvement

    SciTech Connect

    Oender, Hakan; Oguzkurt, Levent; Guer, Serkan; Tekbas, Gueven; Guerel, Kamil; Coskun, Isa; Oezkan, Ugur

    2013-02-15

    To evaluate the results of stent placement for obstructive atherosclerotic aortic disease with or without involvement of the common iliac artery. Forty patients had self-expanding stents primarily or after balloon dilatation in the abdominal aorta between January 2005 and May 2011. All patients had trouble walking. Follow-up examinations were performed with clinical visits; these included color Doppler ultrasonography and computed tomographic angiography. Technical, clinical, and hemodynamic success was achieved in all patients. None of the patients underwent reintervention during the follow-up period, which ranged from 3 months to 6 years (median 24 months). Nine complications occurred in six patients. Of the nine complications, four were distal thromboembolisms, which were successfully treated with catheter-directed thrombolysis or anticoagulation therapy. Endovascular treatment of the obstructive aortic disease using self-expanding stents was safe and effective, with high technical success and long-term patency. Thromboembolic complications were high even though direct stenting was considered protective for thromboembolism formation. Particularly for infrarenal aortic stenosis, it can be recommended as the first-line treatment option for patients with obstructive atherosclerotic aortic disease.

  11. CD14 Directs Adventitial Macrophage Precursor Recruitment: Role in Early Abdominal Aortic Aneurysm Formation

    PubMed Central

    Blomkalns, Andra L.; Gavrila, Daniel; Thomas, Manesh; Neltner, Bonnie S.; Blanco, Victor M.; Benjamin, Stephanie B.; McCormick, Michael L.; Stoll, Lynn L.; Denning, Gerene M.; Collins, Sean P.; Qin, Zhenyu; Daugherty, Alan; Cassis, Lisa A.; Thompson, Robert W.; Weiss, Robert M.; Lindower, Paul D.; Pinney, Susan M.; Chatterjee, Tapan; Weintraub, Neal L.

    2013-01-01

    Background Recruitment of macrophage precursors to the adventitia plays a key role in the pathogenesis of abdominal aortic aneurysms (AAAs), but molecular mechanisms remain undefined. The innate immune signaling molecule CD14 was reported to be upregulated in adventitial macrophages in a murine model of AAA and in monocytes cocultured with aortic adventitial fibroblasts (AoAf) in vitro, concurrent with increased interleukin‐6 (IL‐6) expression. We hypothesized that CD14 plays a crucial role in adventitial macrophage precursor recruitment early during AAA formation. Methods and Results CD14−/− mice were resistant to AAA formation induced by 2 different AAA induction models: aortic elastase infusion and systemic angiotensin II (AngII) infusion. CD14 gene deletion led to reduced aortic macrophage infiltration and diminished elastin degradation. Adventitial monocyte binding to AngII‐infused aorta in vitro was dependent on CD14, and incubation of human acute monocytic leukemia cell line‐1 (THP‐1) monocytes with IL‐6 or conditioned medium from perivascular adipose tissue (PVAT) upregulated CD14 expression. Conditioned medium from AoAf and PVAT induced CD14‐dependent monocyte chemotaxis, which was potentiated by IL‐6. CD14 expression in aorta and plasma CD14 levels were increased in AAA patients compared with controls. Conclusions These findings link CD14 innate immune signaling via a novel IL‐6 amplification loop to adventitial macrophage precursor recruitment in the pathogenesis of AAA. PMID:23537804

  12. Endovascular repair of abdominal aortic aneurysms: vascular anatomy, device selection, procedure, and procedure-specific complications.

    PubMed

    Bryce, Yolanda; Rogoff, Philip; Romanelli, Donald; Reichle, Ralph

    2015-01-01

    Abdominal aortic aneurysm (AAA) is abnormal dilatation of the aorta, carrying a substantial risk of rupture and thereby marked risk of death. Open repair of AAA involves lengthy surgery time, anesthesia, and substantial recovery time. Endovascular aneurysm repair (EVAR) provides a safer option for patients with advanced age and pulmonary, cardiac, and renal dysfunction. Successful endovascular repair of AAA depends on correct selection of patients (on the basis of their vascular anatomy), choice of the correct endoprosthesis, and familiarity with the technique and procedure-specific complications. The type of aneurysm is defined by its location with respect to the renal arteries, whether it is a true or false aneurysm, and whether the common iliac arteries are involved. Vascular anatomy can be divided more technically into aortic neck, aortic aneurysm, pelvic perfusion, and iliac morphology, with grades of difficulty with respect to EVAR, aortic neck morphology being the most common factor to affect EVAR appropriateness. When choosing among the devices available on the market, one must consider the patient's vascular anatomy and choose between devices that provide suprarenal fixation versus those that provide infrarenal fixation. A successful technique can be divided into preprocedural imaging, ancillary procedures before AAA stent-graft placement, the procedure itself, postprocedural medical therapy, and postprocedural imaging surveillance. Imaging surveillance is important in assessing complications such as limb thrombosis, endoleaks, graft migration, enlargement of the aneurysm sac, and rupture. Last, one must consider the issue of radiation safety with regard to EVAR.

  13. Metabolism of benzo(a)pyrene by aortic subcellular fractions in the setting of abdominal aortic aneurysms.

    PubMed

    Ramesh, A; Prins, P A; Perati, P R; Rekhadevi, P V; Sampson, U K

    2016-01-01

    As exposure to polycyclic aromatic hydrocarbons (PAHs; a family of environmental toxicants) have been implicated in cardiovascular diseases, the ability of the aortic tissue to process these toxicants is important from the standpoint of abdominal aortic aneurysms and atherosclerosis. Benzo(a)pyrene (B(a)P), a representative PAH compound is released into the environment from automobile exhausts, industrial emissions, and considerable intake of B(a)P is also expected in people who are smokers and barbecued red meat eaters. Therefore, knowledge of B(a)P metabolism in the cardiovascular system will be of importance in the management of vascular disorders. Toward this end, subcellular fractions (nuclear, cytosolic, mitochondrial, and microsomal) were isolated from the aortic tissues of Apo E mice that received a 5 mg/kg/week of B(a)P for 42 days and 0.71 mg/kg/day for 60 days. The fractions were incubated with 1 and 3 μM B(a)P. Post incubation, samples were extracted with ethyl acetate and analyzed by reverse-phase HPLC. Microsomal B(a)P metabolism was greater than the rest of the fractions. The B(a)P metabolite levels generated by all the subcellular fractions showed a B(a)P exposure concentration-dependent increase for both the weekly and daily B(a)P treatment categories. The preponderance of B(a)P metabolites such as 7,8-dihydrodiol, 3,6-, and 6,12-dione metabolites are interesting due to their reported involvement in B(a)P-induced toxicity through oxidative stress.

  14. Epidermal growth factor receptor inhibitor protects against abdominal aortic aneurysm in a mouse model.

    PubMed

    Obama, Takashi; Tsuji, Toshiyuki; Kobayashi, Tomonori; Fukuda, Yamato; Takayanagi, Takehiko; Taro, Yoshinori; Kawai, Tatsuo; Forrester, Steven J; Elliott, Katherine J; Choi, Eric; Daugherty, Alan; Rizzo, Victor; Eguchi, Satoru

    2015-05-01

    Angiotensin II (Ang II) has been implicated in the development of abdominal aortic aneurysm (AAA). In vascular smooth muscle cells (VSMC), Ang II activates epidermal growth factor receptor (EGFR) mediating growth promotion. We hypothesized that inhibition of EGFR prevents Ang II-dependent AAA. C57BL/6 mice were co-treated with Ang II and β-aminopropionitrile (BAPN) to induce AAA with or without treatment with EGFR inhibitor, erlotinib. Without erlotinib, 64.3% of mice were dead due to aortic rupture. All surviving mice had AAA associated with EGFR activation. Erlotinib-treated mice did not die and developed far fewer AAA. The maximum diameters of abdominal aortas were significantly shorter with erlotinib treatment. In contrast, both erlotinib-treated and non-treated mice developed hypertension. The erlotinib treatment of abdominal aorta was associated with lack of EGFR activation, endoplasmic reticulum (ER) stress, oxidative stress, interleukin-6 induction and matrix deposition. EGFR activation in AAA was also observed in humans. In conclusion, EGFR inhibition appears to protect mice from AAA formation induced by Ang II plus BAPN. The mechanism seems to involve suppression of vascular EGFR and ER stress.

  15. Abdominal aortic aneurysm associated with congenital solitary pelvic kidney treated with novel hybrid technique.

    PubMed

    Malinowski, Michael J; Al-Nouri, Omar; Hershberger, Richard; Halandras, Pegge M; Aulivola, Bernadette; Cho, Jae S

    2014-08-01

    Renal ectopia in the rare condition of associated abdominal aortic aneurysm presents a difficult clinical challenge with respect to access to the aorto-iliac segment and preservation of renal function because of its anomalous renal arterial anatomy and inevitable renal ischemia at the time of open repair. Multiple operative techniques are described throughout the literature to cope with both problems. We report a case of a 57-year-old male with an aorto-iliac aneurysm and a congenital solitary pelvic kidney successfully treated by hybrid total renal revascularization using iliorenal bypass followed by unilateral internal iliac artery coil embolization and conventional endovascular aortic aneurysm repair without any clinical evidence of renal impairment.

  16. Abdominal aortic aneurysm and omega-3 polyunsaturated fatty acids: Mechanisms, animal models, and potential treatment.

    PubMed

    Meital, Lara T; Sandow, Shaun L; Calder, Philip C; Russell, Fraser D

    2017-03-01

    Abdominal aortic aneurysm (AAA) is an inflammatory disease associated with macrophage accumulation in the adventitia, oxidative stress, medial elastin degradation and aortic dilation. Progression of AAA is linked to increased risk of rupture, which carries a high mortality rate. Drug therapies trialled to date lack efficacy and although aneurysm repair is available for patients with large aneurysm, peri-surgical morbidity and mortality have been widely reported. Recent studies using rodent models of AAA suggest that long chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs) and their metabolites can moderate inflammation and oxidative stress perpetuated by infiltrating macrophages and intervene in the destruction of medial elastin. This review examines evidence from these animal studies and related reports of inhibition of inflammation and arrest of aneurysm development following prophylactic supplementation with LC n-3 PUFAs. The efficacy of LC n-3 PUFAs for management of existing aneurysm is unclear and further investigations involving human clinical trials are warranted.

  17. Abdominal aortic aneurysm repair in a patient with bilateral autotransplanted kidneys.

    PubMed

    Neelakandhan, K S; Muralidhar, R; Unnikrishnan, M; Ravimandalam, K

    1994-04-01

    The case is presented of a 38-year-old male who presented with a large 10 cm x 8 cm pulsatile swelling in his abdomen. Thirteen years before, internal iliac arteries had been used to treat long segment occlusions and diseased state of both renal arteries. At the same time both kidneys had been transplanted to the iliac fossae. Digital subtraction angiography revealed a huge abdominal aortic aneurysm. Both kidneys were fully functional. As the renal transplants had been done extraperitoneally an easy transperitoneal approach was now possible. The maximum diameter of the aneurysm was 12 cm. An inclusion graft repair was carried out using a 16-mm woven Dacron graft. In the light of the favourable circumstances it was decided not to take any special protective measures against renal ischemia apart from keeping the aortic cross-clamp time short. The patient could be discharged with patent and normally functioning kidneys 10 days after surgery.

  18. c-Myc Alters Substrate Utilization and O-GlcNAc Protein Posttranslational Modifications without Altering Cardiac Function during Early Aortic Constriction

    PubMed Central

    Ledee, Dolena; Smith, Lincoln; Bruce, Margaret; Kajimoto, Masaki; Isern, Nancy; Portman, Michael A.; Olson, Aaron K.

    2015-01-01

    Hypertrophic stimuli cause transcription of the proto-oncogene c-Myc (Myc). Prior work showed that myocardial knockout of c-Myc (Myc) attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we assessed the interplay between Myc, substrate oxidation and cardiac function during early pressure overload hypertrophy. Mice with cardiac specific, inducible Myc knockout (MycKO-TAC) and non-transgenic littermates (Cont-TAC) were subjected to transverse aortic constriction (TAC; n = 7/group). Additional groups underwent sham surgery (Cont-Sham and MycKO-Sham, n = 5 per group). After two weeks, function was measured in isolated working hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. In sham hearts, Myc knockout did not affect cardiac function or substrate preferences for the citric acid cycle. However, Myc knockout altered fractional contributions during TAC. The unlabeled fractional contribution increased in MycKO-TAC versus Cont-TAC, whereas ketone and free fatty acid fractional contributions decreased. Additionally, protein posttranslational modifications by O-GlcNAc were significantly greater in Cont-TAC versus both Cont-Sham and MycKO-TAC. In conclusion, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy, which may regulate Myc-induced metabolic changes. PMID:26266538

  19. Use of Nanoparticles As Contrast Agents for the Functional and Molecular Imaging of Abdominal Aortic Aneurysm

    PubMed Central

    Emeto, Theophilus I.; Alele, Faith O.; Smith, Amy M.; Smith, Felicity M.; Dougan, Tammy; Golledge, Jonathan

    2017-01-01

    Abdominal aortic aneurysm (AAA) is a degenerative disease of the aorta common in adults older than 65 years of age. AAA is usually imaged using ultrasound or computed tomography. Molecular imaging technologies employing nanoparticles (NPs) have been proposed as novel ways to quantify pathological processes, such as inflammation, within AAAs as a means to identify the risk of rapid progression or rupture. This article reviews the current evidence supporting the role of NP-based imaging in the management of AAA. Currently, ultrasmall superparamagnetic NPs enhanced magnetic resonance imaging appears to hold the greatest potential for imaging macrophage-mediated inflammation in human AAA. PMID:28386544

  20. Use of Nanoparticles As Contrast Agents for the Functional and Molecular Imaging of Abdominal Aortic Aneurysm.

    PubMed

    Emeto, Theophilus I; Alele, Faith O; Smith, Amy M; Smith, Felicity M; Dougan, Tammy; Golledge, Jonathan

    2017-01-01

    Abdominal aortic aneurysm (AAA) is a degenerative disease of the aorta common in adults older than 65 years of age. AAA is usually imaged using ultrasound or computed tomography. Molecular imaging technologies employing nanoparticles (NPs) have been proposed as novel ways to quantify pathological processes, such as inflammation, within AAAs as a means to identify the risk of rapid progression or rupture. This article reviews the current evidence supporting the role of NP-based imaging in the management of AAA. Currently, ultrasmall superparamagnetic NPs enhanced magnetic resonance imaging appears to hold the greatest potential for imaging macrophage-mediated inflammation in human AAA.

  1. Utilization of the National Inpatient Sample for abdominal aortic aneurysm research.

    PubMed

    Dua, Anahita; Ali, Fadwa; Traudt, Elizabeth; Desai, Sapan S

    2017-02-22

    Large administrative databases, including the Medicare database by the Centers for Medicare and Medicaid Services, the National Surgical Quality Improvement Project database sponsored by the American College of Surgeons, and the National Inpatient Sample, have been used by major public health agencies for years. More recently, medical researchers have turned to database research to power studies on diseases that are noted to be relatively scarce. This study aimed to review and discuss the utilization of the National Inpatient Sample for abdominal aortic aneurysm research, inclusive of its advantages, disadvantages, and best practices.

  2. Colorectal cancer associated with abdominal aortic aneurysm: results of EVAR followed by colectomy.

    PubMed

    Illuminati, Giulio; Ceccanei, Gianluca; Pacilè, Maria A; Pizzardi, Giulia; Palumbo, Piergaspare; Vietri, Francesco

    2013-01-01

    The association of colorectal cancer and abdominal aortic aneurysm (AAA) is infrequent but poses special problems of priority of treatment under elective circumstances. The purpose of this study was to retrospectively evaluate the outcome of 16 consecutive patients undergoing endovascular aneurysm repair (EVAR) followed by colectomy. Operative mortality was nil. Operative morbidity included two transient rise of serum creatinine level and one extraperitoneal anastomotic leakage which evolved favourably with conservative treatment. EVAR allowed a very short delay of treatment of colorectal cancer after aneurysm repair, minimizing operative complications.

  3. Total Occlusion of Abdominal Aortic Endograft Successfully Treated with Axillobifemoral Bypass

    PubMed Central

    Shirasugi, Takehiro; Yuri, Koichi; Nomura, Yohei; Yamaguchi, Atsushi; Adachi, Hideo; Morita, Hideki

    2015-01-01

    We report a case of total occlusion of a Zenith bifurcated stent graft 16 months after implantation. A 72-year-old man was admitted to our hospital complaining of bilateral lower extremity numbness, followed by severe rest pain 4 h after sudden onset of symptoms. Computed tomography showed total occlusion of the endograft at the mid-portion of the main body. He underwent left axillobifemoral bypass using a reinforced polytetrafluoroethylene T-shaped graft, leading to resolution of symptoms 7 h after onset. Axillobifemoral bypass successfully relieved acute lower extremity ischemia caused by total occlusion of the abdominal aortic endograft. PMID:26730257

  4. Tuberculous abdominal aortic aneurysm with alimentary tract hemorrhage: a case report with medico-legal implications.

    PubMed

    Xie, Dan; Xie, Kai; Li, Pei; Peng, Yu-Long; Yang, Xiang; Yang, Li-Ying; Cai, Ji-Feng

    2014-04-01

    An autopsy case of sudden death induced by alimentary tract hemorrhage was presented, which was caused by the unexpected rupture of clinically unrecognized tuberculous abdominal aortic aneurysm (TAAA). The initial diagnosis was made of the syndrome of coronary heart disease and hypertensive disease. The detailed autopsy showed that the alimentary tract hemorrhage was caused by a sudden rupture of the mass after posture changing was ascertained as the cause of death. The diagnosis of TAAA was determined by the autopsy findings. Analysis for the medical dispute of TAAA was described, and the difficulty of the diagnosis and medico-legal implications were also discussed.

  5. Endovascular therapy for overcoming challenges presented with blunt abdominal aortic injury.

    PubMed

    Gilani, Ramyar; Saucedo-Crespo, Hector; Scott, Bradford G; Tsai, Peter I; Wall, Metthew J; Mattox, Kenneth L

    2012-05-01

    Blunt abdominal aortic injury (BAAI) is a rare and lethal injury requiring surgical management. Injury patterns can be complex and surgical strategy should accommodate specific case circumstances. Endovascular solutions appear appropriate and preferred in certain cases of BAAI, which, however, may not be applicable due to device limitations in regard to patient anatomy and limited operating room capability. However, endovascular therapy can be pursued with limited fluoroscopy capability and consumable availability providing a solution that is expeditious and effective for select cases of BAAI.

  6. Endovascular Treatment of Blunt Traumatic Abdominal Aortic Occlusion With Kissing Stent Placement

    SciTech Connect

    Idoguchi, Koji Yamaguchi, Masato; Okada, Takuya; Nomura, Yoshikatsu; Sugimura, Kazuro; Okita, Yutaka; Sugimoto, Koji

    2012-10-15

    Blunt traumatic abdominal aortic dissection is extremely rare and potentially deadly. We present the case of a 62-year-old man involved in a frontal car crash. After emergency undergoing laparotomy for bowel injuries, he was referred to our hospital due to acute ischemia of bilateral lower extremities on day 3 after the trauma. Computed tomography and aortography showed an aortobiiliac dissection with complete occlusion. This injury was successfully treated by endovascular treatment with 'kissing'-technique stent placement, which appears to be a safe, effective, and minimally invasive treatment.

  7. Use of spiral computed tomographic angiography in monitoring abdominal aortic aneurysms after transfemoral endovascular repair.

    PubMed Central

    Balm, R; Jacobs, M J

    1997-01-01

    Transfemoral endovascular repair of abdominal aortic aneurysms has proved to be technically feasible in a selected group of patients. However, long-term efficacy has not been proved. Graft performance after implantation can be monitored by a single imaging technique: spiral computed tomographic angiography. With this technique, the parameters for continuing clinical success of the procedure-graft patency, endoleaks, graft migration, attachment site diameter, attachment system failure, and aneurysm diameter-can be monitored. Only in selected cases will an additional imaging technique be necessary. PMID:9339508

  8. Thresholds for Abdominal Aortic Aneurysm Repair in England and the United States.

    PubMed

    Karthikesalingam, Alan; Vidal-Diez, Alberto; Holt, Peter J; Loftus, Ian M; Schermerhorn, Marc L; Soden, Peter A; Landon, Bruce E; Thompson, Matthew M

    2016-11-24

    Background Thresholds for repair of abdominal aortic aneurysms vary considerably among countries. Methods We examined differences between England and the United States in the frequency of aneurysm repair, the mean aneurysm diameter at the time of the procedure, and rates of aneurysm rupture and aneurysm-related death. Data on the frequency of repair of intact (nonruptured) abdominal aortic aneurysms, in-hospital mortality among patients who had undergone aneurysm repair, and rates of aneurysm rupture during the period from 2005 through 2012 were extracted from the Hospital Episode Statistics database in England and the U.S. Nationwide Inpatient Sample. Data on the aneurysm diameter at the time of repair were extracted from the U.K. National Vascular Registry (2014 data) and from the U.S. National Surgical Quality Improvement Program (2013 data). Aneurysm-related mortality during the period from 2005 through 2012 was determined from data obtained from the Centers for Disease Control and Prevention and the U.K. Office of National Statistics. Data were adjusted with the use of direct standardization or conditional logistic regression for differences between England and the United States with respect to population age and sex. Results During the period from 2005 through 2012, a total of 29,300 patients in England and 278,921 patients in the United States underwent repair of intact abdominal aortic aneurysms. Aneurysm repair was less common in England than in the United States (odds ratio, 0.49; 95% confidence interval [CI], 0.48 to 0.49; P<0.001), and aneurysm-related death was more common in England than in the United States (odds ratio, 3.60; 95% CI, 3.55 to 3.64; P<0.001). Hospitalization due to an aneurysm rupture occurred more frequently in England than in the United States (odds ratio, 2.23; 95% CI, 2.19 to 2.27; P<0.001), and the mean aneurysm diameter at the time of repair was larger in England (63.7 mm vs. 58.3 mm, P<0.001). Conclusions We found a lower rate

  9. Sac Hygroma After Endovascular Abdominal Aortic Aneurysm Repair: Successful Treatment with Endograft Relining

    SciTech Connect

    Ryu, Robert K. Palestrant, Sarah; Ryu, Jessica; Trachtenberg, Jeffrey

    2007-06-15

    Aneurysm sac expansion following endovascular abdominal aortic aneurysm repair (EVAR) is typically associated with endoleaks that can be readily diagnosed on computed tomographic angiography (CTA), ultrasound, or catheter-directed arteriography. Sac hygromas are a cause of sac expansion without apparent endoleak and are presumed to be a result of ultrafiltration of serum manifested by accumulation of fibrinous, gelatinous material within the aneurysm sac following EVAR. Although there are no reported associated ruptures, sac expansion is nevertheless disconcerting and intervention is presumably indicated. We report a case of an expanding aneurysm after EVAR secondary to sac hygroma that was successfully treated with relining of the existing, original endograft.

  10. Repair of type I endoleak by chimney technique after endovascular abdominal aortic aneurysm repair

    PubMed Central

    Kim, Na Hee; Kim, Woo Chul; Cho, Soon Gu; Hong, Kee Chun

    2014-01-01

    Endovascular aneurysm repair is a minimally invasive, durable and effective alternative to open surgery for treatment of abdominal aortic aneurysms (AAA). However, in patients who do not have an adequate sealing zone, open surgical repair is required, which may increase mortality and morbidity. An alternative treatment in patients with challenging anatomy is the so-called "chimney graft" technique. Here, we describe a case using the chimney graft technique for treatment of juxtarenal type I endoleak followed by a previous conventional stent graft insertion to the AAA with good results. PMID:24851230

  11. STUDIES ON EXPERIMENTAL HYPERTENSION : IX. THE EFFECT ON BLOOD PRESSURE OF CONSTRICTION OF THE ABDOMINAL AORTA ABOVE AND BELOW THE SITE OF ORIGIN OF BOTH MAIN RENAL ARTERIES.

    PubMed

    Goldblatt, H; Kahn, J R; Hanzal, R F

    1939-04-30

    constriction of the main renal arteries, this accident rarely occurred. When the constriction of the aorta above the origin of the main renal arteries was of moderate degree, or was gradually made very great, the resultant hypertension was not accompanied by impairment of renal excretory function, as determined by urea clearance or by the quantity of urea, creatinine or non-protein nitrogen in the blood, the benign phase of hypertension (3). When the constriction of the aorta was suddenly made very great, impairment of the renal excretory function usually followed, and the animal developed fatal convulsive uremia and characteristic vascular lesions, the malignant phase of hypertension (9). These facts, are all indicative of the renal origin of the hypertension which results from the constriction of the aorta just above the origin of both main renal arteries. Hypertension did not persist for a sufficiently long time to permit any conclusive comparison between the effect of the high and low pressures on the structure of the vascular system, above and below the site of the clamp, respectively. During the period of survival of these animals, no significant differences were observed between the appearance of the vascular system of the upper part of the body and that of the lower part of the body, and significant cardiac hypertrophy did not develop. In the aorta and large arteries, intimal arteriosclerosis was not observed. In the aorta of one old animal several small plaques of calcification were found in the media, but these were present in the portion of the aorta below, as well as above the clamp, and they were no larger or more abundant than were observed in some old dogs with normal blood pressure. Dogs 3-50 and 3-83, that are still alive, with very high blood pressure above the site of the aortic clamps, and relatively low pressure (though greater than normal) below the site of the aortic clamps, will be valuable for the determination of possible differences between the

  12. ACE2 Inhibits Angiotensin II-Induced Abdominal Aortic Aneurysm in Mice.

    PubMed

    Hao, QingQing; Dong, XueFei; Chen, Xu; Yan, Feng; Wang, Xiaoyu; Shi, Haishui; Dong, Bo

    2017-01-31

    Recent study have demonstrated that ACE2 plays an important role in the pathogenesis of abdominal Aortic Aneurysm (AAA). But, little study was reported about the direct effect of ACE2 overexpression on the aneurysm. In this study, we hypothesize that overexpression of ACE2 may prevent the pathogenesis of aneurysm by decreasing RAS activation. Thirty-nine Mice were assigned to 3 groups randomly (n=13 in each group), ACE2 group, Ad.EGFP group and Control group. After 8-week treatment, abdominal aortas with AAA were obtained for HE staining, VVG, immunohistochemistry and Western blotting. The incidence and severity of AAA, macrophage infiltration and MMP protein expression were all detected. The results showed that ACE2 gene transfer significantly decreased the occurrence of AAA and inhibited AAA formation in ApoE-/- mice by inhibiting inflammatory response and MMP activation, the mechanisms may involve decreased ERK and AngII-NF-kB signaling pathways.

  13. Endovascular Abdominal Aortic Aneurysm Repair by Means of the Chimney Technique in a Patient with Crossed Fused Renal Ectopia

    PubMed Central

    Kfoury, Elias; Almanfi, Abdelkader; Dougherty, Kathryn G.

    2016-01-01

    Crossed fused renal ectopia, a congenital anomaly in 1 of 7,000 individuals, presents a challenge during endovascular treatment of abdominal aortic aneurysm. Most treatment approaches in these patients have involved open surgical repair of the aneurysm or endovascular repair with coverage of the ectopic renal artery. We present what we think is the first case of endovascular abdominal aortic aneurysm repair with use of the chimney technique (parallel stent-grafting) to preserve an ectopic renal artery, in an 88-year-old man who was at high risk for open surgery. In addition to the patient's case, we discuss the relevant medical literature. PMID:27303239

  14. Endovascular Repair of Abdominal Aortic Aneurysms in the Presence of a Transplanted Kidney

    SciTech Connect

    Silverberg, Daniel Yalon, Tal; Halak, Moshe

    2015-08-15

    PurposeTo present our experience performing endovascular repair of abdominal aortic aneurysms in kidney transplanted patients.MethodsA retrospective review of all patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA) performed at our institution from 2007 to 2014. We identified all patients who had previously undergone a kidney transplant. Data collected included: comorbidities, preoperative imaging modalities, indication for surgery, stent graft configurations, pre- and postoperative renal function, perioperative complications, and survival rates.ResultsA total of 267 EVARs were performed. Six (2 %) had a transplanted kidney. Mean age was 74 (range, 64–82) years; five were males. Mean time from transplantation to EVAR was 7.5 (range, 2–12) years. Five underwent preoperative planning with noncontrast modalities only. Devices used included bifurcated (n = 3), aortouniiliac (n = 2), and tube (n = 1) stent grafts. Technical success was achieved in all patients. None experienced deterioration in renal function. Median follow-up was 39 (range, 6–51) months. Four patients were alive at the time of the study. Two patients expired during the period of follow-up from unrelated causes.ConclusionsEVAR is an effective modality for the management of AAAs in the coexistence of a transplanted kidney. It can be performed with minimal morbidity and mortality without harming the transplanted kidney. Special consideration should be given to device configuration to minimize damage to the renal graft.

  15. Pravastatin activates activator protein 2 alpha to argument the angiotensin II-induced abdominal aortic aneurysms.

    PubMed

    Ma, Hui; Liang, Wen-Jing; Shan, Mei-Rong; Wang, Xue-Qing; Zhou, Sheng-Nan; Chen, Yuan; Guo, Tao; Li, Peng; Yu, Hai-Ya; Liu, Chao; Yin, Ya-Ling; Wang, Yu-Lin; Dong, Bo; Pang, Xin-Yan; Wang, Shuang-Xi

    2017-02-04

    We have previously reported that activation of AMP-activated kinase alpha 2 (AMPKα2) by nicotine or angiotensin II (AngII) instigates formation of abdominal aortic aneurysms (AAA) in Apoe-/- mice. Statins, used to treat hyperlipidemia widely, activate AMPK in vascular cells. We sought to examine the effects of pravastatin on AAA formation and uncover the molecular mechanism. The AAA model was induced by AngII and evaluated by incidence, elastin degradation, and maximal abdominal aortic diameter in Apoe-/- mice. The phosphorylated levels of AMPKα2 and activator protein 2 alpha (AP-2α) were examined in cultured vascular smooth muscle cells (VSMCs) or in mice. We observed that pravastatin (50 mg/kg/day, 8 weeks) remarkably increased the AngII-induced AAA incidence in mice. In VSMCs, pravastatin increased the levels of pAMPK, pAP-2α, and MMP2 in both basal and AngII-stressed conditions, which were abolished by tempol and compound C. Pravastatin-upregulated MMP2 was abrogated by AMPKα2 or AP-2α siRNA. Lentivirus-mediated gene silence of AMPKα2 or AP-2α abolished pravastatin-worsened AAA formations in AngII-infused Apoe-/- mice. Clinical investigations demonstrated that both AMPKα2 and AP-2α phosphorylations were increased in AAA patients or human subjects taking pravastatin. In conclusion, pravastatin promotes AAA formation through AMPKα2-dependent AP-2α activations.

  16. The cellular component in the parietal infiltrate of inflammatory abdominal aortic aneurysms (IAAA).

    PubMed

    Stella, A; Gargiulo, M; Pasquinelli, G; Preda, P; Faggioli, G L; Cenacchi, G; D'Addato, M

    1991-02-01

    Eight cases of inflammatory abdominal aortic aneurysm (IAAA) (group I) and a control group of ten cases of atherosclerotic abdominal aortic aneurysm (AAA) with little or no parietal inflammatory infiltrate (group II) were studied; using light microscopy, transmission electron microscopy (TEM), and immunohistochemistry. These were used to define cell composition in the inflammatory process, the degree of cell activation and alteration of connective tissue. Large numbers of B lymphocytes were present in IAAA with preservation of the T4/T8 ratio. In addition, HLA-DR and the IL2-R antigen (specific for activated cells) were widely expressed in the cell population. The interstitial matrix contained deposits of IgG, IgM and C3c together with an increase in type III collagen and a reduction in elastin which appeared fragmented and swollen. This study, therefore, characterised the cellular component of the parietal inflammatory infiltrate in IAAA. The degree of activation shown by these cell elements and the activation of complement suggest that the relevant antigen may have been localised in the aneurysm wall at the time of observation.

  17. Chronic Contained Rupture of an Abdominal Aortic Aneurysm: From Diagnosis to Endovascular Resolution

    SciTech Connect

    Gandini, Roberto Chiocchi, Marcello; Maresca, Luciano; Pipitone, Vincenzo; Messina, Massimo; Simonetti, Giovanni

    2008-07-15

    A male patient, 69 years old, presented with fever, leucocytosis, and persistent low back pain; he also had an abdominal aortic aneurysm (AAA), as previously diagnosed by Doppler UltraSound (US), and was admitted to our hospital. On multislice computed tomography (msCT), a large abdominal mass having no definite border and involving the aorta and both of the psoas muscles was seen. This mass involved the forth-lumbar vertebra with lysis, thus simulating AAA rupture into a paraspinal collection; it was initially considered a paraspinal abscess. After magnetic resonance imaging examination and culture of the fluid aspirated from the mass, no infective organisms were found; therefore, a diagnosisof chronically contained AAA rupture was made, and an aortic endoprosthesis was subsequently implanted. The patient was discharged with decreased lumbar pain. At 12-month follow-up, no evidence of leakage was observed. To our knowledge, this is the first case of endoprosthesis implantation in a patient, who was a poor candidate for surgical intervention due to renal failure, leucocytosis and high fever, having a chronically contained AAA ruptured simulatingspodilodiscitis abscess. Appropriate diagnosis and therapy resolved potentially crippling pathology and avoided surgical graft-related complications.

  18. Aneurysmal Lesions of Patients with Abdominal Aortic Aneurysm Contain Clonally Expanded T Cells

    PubMed Central

    Lu, Song; White, John V.; Lin, Wan Lu; Zhang, Xiaoying; Solomides, Charalambos; Evans, Kyle; Ntaoula, Nectaria; Nwaneshiudu, Ifeyinwa; Gaughan, John; Monos, Dimitri S.; Oleszak, Emilia L.

    2014-01-01

    Abdominal aortic aneurysm (AAA) is a common disease with often life-threatening consequences. This vascular disorder is responsible for 1–2% of all deaths in men aged 65 years or older. Autoimmunity may be responsible for the pathogenesis of AAA. Although it is well documented that infiltrating T cells are essentially always present in AAA lesions, little is known about their role in the initiation and/or progression of the disease. To determine whether T cells infiltrating AAA lesions contain clonally expanded populations of T cells, we amplified β-chain TCR transcripts by the nonpalindromic adaptor–PCR/Vβ-specific PCR and/or Vβ-specific PCR, followed by cloning and sequencing. We report in this article that aortic abdominal aneurysmal lesions from 8 of 10 patients with AAA contained oligoclonal populations of T cells. Multiple identical copies of β-chain TCR transcripts were identified in these patients. These clonal expansions are statistically significant. These results demonstrate that αβ TCR+ T lymphocytes infiltrating aneurysmal lesions of patients with AAA have undergone proliferation and clonal expansion in vivo at the site of the aneurysmal lesion, in response to unidentified self- or nonself Ags. This evidence supports the hypothesis that AAA is a specific Ag–driven T cell disease. PMID:24752442

  19. [A case of inflammatory abdominal aortic aneurysm with associated inferior vena caval and bilateral ureteral obstruction].

    PubMed

    Hirose, Y; Hayashida, K; Ishida, Y; Hamada, S; Takahashi, N; Takamiya, M; Ando, M; Nishimura, T

    1994-09-01

    One year ago, a 48-year-old man complained of dyspnea, and was diagnosed as mitral valve regurgitation and aortic dissection. He underwent mitral valve replacement and aortic arch grafting. He was also pointed out to have an inflammatory aortic aneurysm (IAAA) in the infrarenal abdominal aorta, but did not undergo surgery. At this admission, he had lumbago and low grade fever probably due to deterioration of the IAAA. On the preoperative radionuclide studies, inferior vena caval obstruction and bilateral ureteral obstruction or severe stenosis were demonstrated by 99mTc-MAA venography and 123I-OIH renogram, respectively. 67Ga scan showed faint abnormal accumulation at the IAAA. He underwent surgery. IAAA had a thick wall in white and hard fibrotic tissue adhered closely to duodenum, jejunum, inferior vena cava and bilateral ureters. After surgery, his renal function was improved. In this case, radionuclide studies were useful for detecting the inferior vena caval obstruction, assessing renal function and inflammatory activity.

  20. Helical CT Angiography of Abdominal Aortic Aneurysms Treated with Suprarenal Stent Grafting: A Pictorial Essay

    SciTech Connect

    Sun Zhonghua

    2003-06-15

    The endovascular repair of abdominal aorticaneurysm (AAA) with stent grafts is rapidly becoming an important alternative to open repair. Suprarenal stent grafting, recently modified from conventional infrarenal stent grafting, is a technique for the purpose of treating patients with inappropriate aneurysm necks.Unlike open repair, the success of endoluminal repair cannot be ascertained by means of direct examination and thus relies on imaging results. The use of conventional angiography for arterial imaging has become less dominant, while helical computed tomography angiography(CTA) has become the imaging modality of choice for both preoperative assessment and postoperative followup after treatment with stent graft implants. There is an increasing likelihood that radiologists will become more and more involved in the procedure of aortic stent grafting and in giving the radiological report on these patients treated with stent grafts. It is necessary for radiologists to be familiar with the imaging findings, including common and uncommon appearances following aortic stent grafting. The purpose of this pictorial essay is to describe and present normal and abnormal imaging appearances following aortic stent grafting based on helical CTA.

  1. Decreased vascular smooth muscle cell density in medial degeneration of human abdominal aortic aneurysms.

    PubMed Central

    López-Candales, A.; Holmes, D. R.; Liao, S.; Scott, M. J.; Wickline, S. A.; Thompson, R. W.

    1997-01-01

    Abdominal aortic aneurysms (AAAs) are characterized by structural deterioration of the aortic wall leading to progressive aortic dilatation and eventual rupture. The histopathological changes in AAAs are particularly evident within the elastic media, which is normally dominated by vascular smooth muscle cells (SMCs). To determine whether a decrease in vascular SMCs contributes to medial degeneration, we measured SMC density in 21 normal and pathological human abdominal aortic tissue specimens using immunohistochemistry for alpha-SMC actin and direct cell counts (medial SMCs per high-power field (HPF)). Medial SMC density was not significantly different between normal aorta (n = 5; 199.5 +/- 14.9 SMCs/HPF) and atherosclerotic occlusive disease (n = 6; 176.4 +/- 13.9 SMCs/HPF), but it was reduced by 74% in AAA (n = 10; 50.9 +/- 6.1 SMCs/HPF; P < 0.01 versus normal aorta). Light and electron microscopy revealed no evidence of overt cellular necrosis, but SMCs in AAAs exhibited ultrastructural changes consistent with apoptosis. Using in situ end-labeling (ISEL) of fragmented DNA to detect apoptotic cells, up to 30% of aortic wall cells were ISEL positive in AAAs. By double-labeling techniques, many of these cells were alpha-actin-positive SMCs distributed throughout the degenerative media. In contrast, ISEL-positive cells were observed only within the intimal plaque in atherosclerotic occlusive disease. The amount of p53 protein detected by immunoblotting was increased nearly fourfold in AAA compared with normal aorta and atherosclerotic occlusive disease (P < 0.01), and immunoreactive p53 was localized to lymphocytes and residual SMCs in the aneurysm wall. Using reverse transcription polymerase chain reaction assays a substantial amount of p53 mRNA expression was observed in AAAs. These results demonstrate that medial SMC density is significantly decreased in human AAA tissues associated with evidence of SMC apoptosis and increased production of p53, a potential

  2. Increased risk of the abdominal aortic aneurysm in carriers of the MTHFR 677T allele.

    PubMed

    Strauss, Ewa; Waliszewski, Krzysztof; Gabriel, Marcin; Zapalski, Stanisław; Pawlak, Andrzej L

    2003-01-01

    Abdominal aortic aneurysm (AAA) presents itself as a progressive dilation of the abdominal aorta, leading--if untreated--to rupture. It is a common disease of the elderly, with a complex etiology. Several genetic, biochemical and environmental factors are recognized as relevant for the pathogenesis of AAA. We determined the polymorphism of the MTHFR (methylenetetrahydrofolate reductase) gene within the fourth exon (C677T) in 63 patients with AAA and compared it to that in 75 subjects of the population sample. The frequencies of the C/C, C/T and T/T genotypes were 65%, 27%, and 8% in the population sample and 33%, 60%, and 6% in the patients. This corresponds to a 4.4-fold greater risk of AAA in subjects who have the 677C/T variant of MTHFR, as compared with those who are 677C/C (p < 0.0001; 95% CI=2.11-9.34). The frequency of allele MTHFR 677T in patients (0.37) was higher than in the population sample (0.21; p < 0.007). This association between the common allele of the MTHFR gene--MTHFR 677T--and the development of AAA suggests that elevated homocysteine (Hcy) may disturb the function of the aortic wall. The disturbance may involve enhancement of elastin degradation, the process enhanced by mild hyperhomocysteinemia in minipigs. The magnitude of this effect, which refers to the AAA patients unselected for familial occurrence, indicates that the disturbance of aortic wall physiology caused by the presence of the MTHFR 677T allele is greater than the effect of the earlier described allele disequilibrium at the polymorphic alleles of the PAI1 (plasminogen activator inhibitor 1) gene seen only in familial cases of AAA.

  3. 3-D segmentation and quantitative analysis of inner and outer walls of thrombotic abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Lee, Kyungmoo; Yin, Yin; Wahle, Andreas; Olszewski, Mark E.; Sonka, Milan

    2008-03-01

    An abdominal aortic aneurysm (AAA) is an area of a localized widening of the abdominal aorta, with a frequent presence of thrombus. A ruptured aneurysm can cause death due to severe internal bleeding. AAA thrombus segmentation and quantitative analysis are of paramount importance for diagnosis, risk assessment, and determination of treatment options. Until now, only a small number of methods for thrombus segmentation and analysis have been presented in the literature, either requiring substantial user interaction or exhibiting insufficient performance. We report a novel method offering minimal user interaction and high accuracy. Our thrombus segmentation method is composed of an initial automated luminal surface segmentation, followed by a cost function-based optimal segmentation of the inner and outer surfaces of the aortic wall. The approach utilizes the power and flexibility of the optimal triangle mesh-based 3-D graph search method, in which cost functions for thrombus inner and outer surfaces are based on gradient magnitudes. Sometimes local failures caused by image ambiguity occur, in which case several control points are used to guide the computer segmentation without the need to trace borders manually. Our method was tested in 9 MDCT image datasets (951 image slices). With the exception of a case in which the thrombus was highly eccentric, visually acceptable aortic lumen and thrombus segmentation results were achieved. No user interaction was used in 3 out of 8 datasets, and 7.80 +/- 2.71 mouse clicks per case / 0.083 +/- 0.035 mouse clicks per image slice were required in the remaining 5 datasets.

  4. Cathepsin G deficiency reduces peri-aortic calcium chloride injury-induced abdominal aortic aneurysms in mice

    PubMed Central

    Wang, Jing; Sukhova, Galina K.; Liu, Jian; Ozaki, Keith; Lesner, Adam; Libby, Peter; Kovanen, Petri T.; Shi, Guo-Ping

    2014-01-01

    Objective Cathepsin G (CatG) is a serine protease that mediates angiotensin-I (Ang-I) to angiotensin-II (Ang-II) conversion and is highly expressed in human abdominal aortic aneurysms (AAAs). However, it remains untested whether this protease participates in the pathogenesis of AAA. Methods and Results Immunofluorescent double staining demonstrated the expression of CatG in smooth-muscle cells (SMCs), macrophages, and endothelial cells (ECs) in human AAA lesions (n=12), but not in AAA-free aortas (n=10). While inflammatory cytokines induced CatG expression, high glucose increased CatG activity in producing Ang-II and angiotensin-converting enzyme (ACE) in SMCs, which could be fully blocked by a CatG-selective inhibitor or its siRNA. To test whether CatG contributes to AAA development, we generated CatG and low-density lipoprotein receptor (LDLr) double deficient (Ldlr−/−Ctsg−/−) mice and their littermate controls (Ldlr−/−Ctsg+/+). Absence of CatG did not affect Ang-II infusion-induced AAAs. In contrast, in Ang-II-independent AAAs induced by peri-aortic CaCl2 injury (n=12 per group), CatG deficiency significantly reduced aortic diameter increase (58.33%±6.83% vs. 31.67%±5.75%, P=0.007), aortic lesion area (0.35±0.04 mm2 vs. 0.21±0.02 mm2, P=0.005), and aortic wall elastin fragmentation grade (2.75±0.18 vs. 1.58±0.17, P=0.002) along with reduced lesion collagen content grade (2.80±0.17 vs. 2.12±0.17, P=0.009) without affecting indices of lesion inflammation, angiogenesis, cell proliferation, or apoptosis. In vitro elastin degradation assays demonstrated that CaCl2-induced AAA lesions from Ldlr−/−Ctsg−/− mice contained much lower elastinolytic activity than in those from littermate control mice. Gelatin gel zymogram assay suggested that absence of CatG in CaCl2-induced AAA lesions also reduced the activity of elastinolytic matrix metalloproteinase (MMP)-2 and MMP-9. Conclusion CatG may contribute to CaCl2-induced experimental AAAs directly

  5. In vivo characterization of a new abdominal aortic aneurysm mouse model with conventional and molecular MRI

    PubMed Central

    Klink, Ahmed; Heynens, Joeri; Herranz, Beatriz; Lobatto, Mark E.; Arias, Teresa; Sanders, Honorius M. H. F.; Strijkers, Gustav J.; Merkx, Maarten; Nicolay, Klaas; Fuster, Valentin; Tedgui, Alain; Mallat, Ziad; Mulder, Willem J.M.; Fayad, Zahi A.

    2014-01-01

    Objectives To use non-invasive conventional and molecular magnetic resonance imaging (MRI) to detect and characterize abdominal aortic aneurysms (AAAs) in vivo. Background Collagen is an essential constituent of aneurysms. Non-invasive MRI of collagen may represent an opportunity to help detect and better characterize AAA and initiate intervention. Methods We used an AAA C57BL/6 mouse model where a combination of angiotensin-II infusion and TGF-β neutralization results in AAA formation with incidence of aortic rupture. High-resolution multi-sequence MRI was performed to characterize the temporal progression of AAA. To allow molecular MRI of collagen, paramagnetic/fluorescent micellar nanoparticles functionalized with a collagen-binding protein (CNA-35) were intravenously administered. In vivo imaging results were corroborated with immunohistochemistry and confocal fluorescence microscopy. Results High-resolution multi-sequence MRI allowed the visualization of the primary fibrotic response in the aortic wall. As the aneurysm progressed, the formation of a secondary channel or dissection was detected. Further analysis revealed a dramatic increase of the aortic diameter. Injection of CNA-35 micelles resulted in a significant higher MR signal enhancement in the aneurysmal wall compared to non-specific micelles. Histological studies demonstrated the presence of collagen in regions of MR signal enhancement and confocal microscopy proved the precise colocalization of CNA-35 micelles with collagen-I. In addition, in a proof of concept experiment, we have shown the potential of CNA-35 micelles to discriminate between stable AAA lesions and aneurysms that were likely to rapidly progress/rupture. Conclusion Multi-sequence MRI allowed longitudinal monitoring of AAA progression while the presence of collagen was visualized by nanoparticle-enhanced MRI. PMID:22133853

  6. Rupture and bleeding secondary to renal infarction in a patient with an abdominal aortic aneurysm.

    PubMed

    Hiraoka, Toshifumi; Mukai, Shogo; Obata, Shogo; Morimoto, Hironobu; Uchida, Hiroaki; Yamane, Yoshitaka

    2014-01-01

    A 57-year-old man had been followed up for severe left ventricular dysfunction after acute myocardial infarction with a left ventricular thrombus. He had been treated with anticoagulant and antiplatelet therapy and was admitted to our hospital because of abdominal pain and shock. He had no prior episode of trauma. The electrocardiogram (ECG) showed no changes compared with the previous ECG. Enhanced abdominal computed tomography (CT) showed a retroperitoneal hematoma around an abdominal aortic aneurysm (AAA) and the right kidney. We suspected rupture of AAA or the right kidney, and we performed AAA replacement with a Y-shaped graft and nephrectomy of the right kidney. Pathological examination revealed hemorrhagic infarction of the lower part of the right kidney, with hemorrhage and rupture at the center of the infarct. In our case, enhanced CT showed extravasation from the lower part of the right kidney. In addition, postoperative echocardiography showed that the left ventricular thrombus had disappeared. We report a case of rupture and bleeding secondary to renal infarction in a patient with an AAA.

  7. Comparative Effectiveness of Endovascular versus Open Repair of Ruptured Abdominal Aortic Aneurysm in the Medicare Population

    PubMed Central

    Edwards, Samuel T.; Schermerhorn, Marc L.; O’Malley, A. James; Bensley, Rodney P.; Hurks, Rob; Cotterill, Philip; Landon, Bruce E.

    2015-01-01

    Objectives Endovascular abdominal aortic aneurysm repair (EVAR) is increasingly used for emergent treatment of ruptured abdominal aortic aneurysm (rAAA). We sought to compare the perioperative and long-term mortality, procedure-related complications and rates of re-intervention of EVAR versus open aortic repair of rAAA in Medicare beneficiaries. Methods We examined perioperative and long-term mortality and complications after EVAR or open aortic repair performed for rAAA in all traditional Medicare beneficiaries discharged from a US hospital from 2001–2008. Patients were propensity score matched on baseline demographics, coexisting conditions, admission source, and hospital volume of rAAA repair and sensitivity analyses were performed to evaluate the impact of bias that might have resulted from unmeasured confounders Results Of 10,998 patients with repaired rAAA, 1126 underwent EVAR and 9872 underwent open repair. Propensity score matching yielded 1099 patient pairs. The average age was 78 years, and 72.4% were male. Perioperative mortality for EVAR and open repair were 33.8% and 47.7% respectively (p<0.001) and this difference persisted for more than four years. EVAR patients had higher rates of AAA-related reinterventions when compared with open repair patients (endovascular reintervention at 36 months 10.9% vs 1.5%, p<0.001), whereas open patients had more laparotomy related complications (incisional hernia repair at 36 months 1.8% vs. 6.2% p<0.001, all surgical complications at 36 months 4.4% vs. 9.1%, p<0.001). Use of EVAR for rAAA has increased from 6% of cases in 2001 to 31% of cases in 2008, while over the same time period overall 30-day mortality for admission for rAAA regardless of treatment has decreased from 55.8% to 50.9%. Conclusions EVAR for rAAA is associated with lower perioperative and long term mortality in Medicare beneficiaries. Increasing adoption of EVAR for rAAA is associated with an overall decrease in mortality of patients hospitalized

  8. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  9. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  10. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  11. 42 CFR 410.19 - Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Ultrasound screening for abdominal aortic aneurysms: Condition for and limitation on coverage. 410.19 Section 410.19 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL...

  12. Application of physician-modified fenestrated stent graft in urgent endovascular repair of abdominal aortic aneurysm with hostile neck anatomy

    PubMed Central

    Zeng, Rong; Ye, Wei; Liu, Changwei; Wang, Xuan; Song, Xiaojun; Ni, Leng; Liu, Bao; Li, Yongjun; Zheng, Yuehong

    2016-01-01

    Abstract Background: This study aimed to evaluate the feasibility and effectiveness of the Gore Excluder aortic stent graft (WL Gore & Associates, Inc., Flagstaff, AZ) using the C3 Delivery System after physician modification of fenestration for the urgent treatment of patients with abdominal aortic aneurysm showing hostile neck anatomy. Case summary: Three urgent cases of abdominal aortic aneurysm with hostile neck anatomy symptom with abdominal pain were reported. The same fenestration method was applied to align the target superior mesenteric artery and bilateral renal arteries with 1 scallop and 2 fenestrations, followed by the reconstruction of the target artery using a bare-metal stent or stent graft. Balloon-assisted positioning and image fusion technology were intraoperatively applied to assist the accurate release of the stent graft body. The follow-up periods for all cases exceeded 6 months, showing smooth circulation in the target arteries with no endoleaks. Conclusion: In the absence of other available treatment methods, it is feasible to use a stent graft with physician-modified fenestration for the urgent endovascular repair of abdominal aortic aneurysm with hostile neck anatomy. However, this procedure's long-term efficacy needs to be further investigated. PMID:27861397

  13. A Case Report on the Successful Treatment of Streptococcus pneumoniae-Induced Infectious Abdominal Aortic Aneurysm Initially Presenting with Meningitis

    PubMed Central

    Kawatani, Yohei; Nakamura, Yoshitsugu; Hayashi, Yujiro; Taneichi, Tetsuyoshi; Ito, Yujiro; Kurobe, Hirotsugu; Suda, Yuji; Hori, Takaki

    2015-01-01

    Infectious abdominal aortic aneurysms often present with abdominal and lower back pain, but prolonged fever may be the only symptom. Infectious abdominal aortic aneurysms initially presenting with meningitis are extremely rare; there are no reports of their successful treatment. Cases with Streptococcus pneumoniae as the causative bacteria are even rarer with a higher mortality rate than those caused by other bacteria. We present the case of a 65-year-old man with lower limb weakness and back pain. Examination revealed fever and neck stiffness. Cerebrospinal fluid showed leukocytosis and low glucose levels. The patient was diagnosed with meningitis and bacteremia caused by Streptococcus pneumoniae and treated with antibiotics. Fever, inflammatory response, and neurologic findings showed improvement. However, abdominal computed tomography revealed an aneurysm not present on admission. Antibiotics were continued, and a rifampicin soaked artificial vascular graft was implanted. Tissue cultures showed no bacteria, and histological findings indicated inflammation with high leukocyte levels. There were no postoperative complications or neurologic abnormalities. Physical examination, blood tests, and computed tomography confirmed there was no relapse over the following 13 months. This is the first reported case of survival of a patient with an infectious abdominal aortic aneurysm initially presenting with meningitis caused by Streptococcus pneumoniae. PMID:26779361

  14. Uncluttered single-image visualization of the abdominal aortic vessel tree: Method and evaluation

    SciTech Connect

    Won, Joong-Ho; Rosenberg, Jarrett; Rubin, Geoffrey D.; Napel, Sandy

    2009-11-15

    Purpose: The authors develop a method to visualize the abdominal aorta and its branches, obtained by CT or MR angiography, in a single 2D stylistic image without overlap among branches. Methods: The abdominal aortic vasculature is modeled as an articulated object whose underlying topology is a rooted tree. The inputs to the algorithm are the 3D centerlines of the abdominal aorta, its branches, and their associated diameter information. The visualization problem is formulated as an optimization problem that finds a spatial configuration of the bounding boxes of the centerlines most similar to the projection of the input into a given viewing direction (e.g., anteroposterior), while not introducing intersections among the boxes. The optimization algorithm minimizes a score function regarding the overlap of the bounding boxes and the deviation from the input. The output of the algorithm is used to produce a stylistic visualization, made of the 2D centerlines modulated by the associated diameter information, on a plane. The authors performed a preliminary evaluation by asking three radiologists to label 366 arterial branches from the 30 visualizations of five cases produced by the method. Each of the five patients was presented in six different variant images, selected from ten variants with the three lowest and three highest scores. For each label, they assigned confidence and distortion ratings (low/medium/high). They studied the association between the quantitative metrics measured from the visualization and the subjective ratings by the radiologists. Results: All resulting visualizations were free from branch overlaps. Labeling accuracies of the three readers were 93.4%, 94.5%, and 95.4%, respectively. For the total of 1098 samples, the distortion ratings were low: 77.39%, medium: 10.48%, and high: 12.12%. The confidence ratings were low: 5.56%, medium: 16.50%, and high: 77.94%. The association study shows that the proposed quantitative metrics can predict a reader

  15. The inflammatory abdominal aortic aneurysm and coronary artery disease. Case report and review.

    PubMed

    Monte, I; Capodanno, D; Licciardi, S; Ferraro, C; Giannone, M T; Grasso, S; Nicolosi, E

    2006-04-01

    Inflammatory abdominal aortic aneurysm (IAAA) is defined as an unusually thickened aneurysmatic wall, encircled by a wide dense perianeurysmal and/or retroperitoneal fibrosis with adjacent tissues adhesion, and is now considered as an extreme shape of the common phlogistic process involved in atherosclerotic plaque formation. Latest studies demonstrated that inflammation plays an important role in coronary disease and in other atherosclerosis manifestations. We introduce the clinical case of a patient with IAAA who developed an acute myocardial infarction 6 months after the surgical procedure on the aorta. Through a literature review about IAAA we stress the clinical usefulness of the inflammatory markers as independent predictors in management of patients with coronary disease and we present the hypothesis, related to the introduced case, of an advanced coronary disease, aggravated or clinically revealed after the cytokine storm related to important localized inflammatory engagements or great vascular surgery treatments.

  16. Genetic Algorithm for Analysis of Abdominal Aortic Aneurysms in Radiology Reports

    SciTech Connect

    Patton, Robert M; Beckerman, Barbara G; Treadwell, Jim N; Potok, Thomas E

    2010-01-01

    An abdominal aortic aneurysm is a problem in which the wall of the artery that supplies blood to the abdomen and lower extremities expands under pressure or balloons outward. Patients must undergo surgery to repair such aneurysm, and there is currently no known indicator of success or failure from this surgery. Our work uses a genetic algorithm to analyze radiology reports from these patients to look for common patterns in the language used as well as common features of both successful and unsuccessful surgieries. The results of the genetic algorithm show that patients with complications or unusual characteristics can be identified from a set of radiology reports without the use of search keywords, clustering, categorization, or ontology. This allows medical researchers to search and identify interesting patient records without the need for explicitly defining what interesting patient records are.

  17. Management of abdominal aortic aneurysms: which risk factors play a role in decision-making?

    PubMed

    Rutherford, Robert B

    2008-09-01

    There are three choices for management of abdominal aortic aneurysms (AAA), ie, endovascular repair (EVAR), open repair (OR), and continuing surveillance (OBS). The treating physician must weigh the risk of no intervention, in terms of ultimate death from rupture, against the more immediate risk associated with either form of repair, considering in the process those risk factors that directly or indirectly relate to outcome. These risk factors include AAA size and the patient's comorbidities, age, gender, and AAA anatomy, as well as the skills and experience of the treating physicians and the health care environment in which the patient is treated. While individualization is clearly required, a generalizable platform for decision-making derived from past trials and other pertinent observational studies is also useful. This article attempts to present pertinent background information and develop it into generally applicable guidelines.

  18. Fused ureters in patient with horseshoe kidney and aortic abdominal aneurysm.

    PubMed

    Obidike, Stephen; Woha, Akeh; Aftab, Fuad

    2014-11-28

    Horseshoe kidney (HSK) is a very common developmental abnormality in the kidney. They are associated with abnormalities like multiple renal arteries, abnormal position of the ureter in the renal pelvis and highly placed ureteropelvic junction. These can result in urological complications. However, the ureters run their separate course and empty individually into the urinary bladder. Surprisingly, anatomical anomalies do occur and can lead to unexpected findings on investigation or surgical treatment. Such anomalies can present diagnostic and management challenges to unsuspecting clinicians. This report deals with one of such anomalies that seem not to have been reported before in the literature. This case is a rare finding of fused ureters over the renal isthmus in a patient with HSK who also has aortic abdominal aneurysm (AAA). Simultaneous occurrences of HSK and AAA have been reported severally in the past, and the authors are paying attention on the ureteral anomaly.

  19. Changes in wall shear stresses in abdominal aortic aneurysms with increasing wall stiffness

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Fernandez, Miguel

    2006-11-01

    During the growth of abdominal aortic aneurysms, local changes occur in the composition and structure of the diseased wall, resulting in its stiffening. A numerical simulation of the fluid structure interactions is performed in idealized models of aneurysms using a finite element method. A full coupling of the equations governing the pulsatile blood flow and the deformation of the compliant wall is undertaken. The effect of the progressive stiffening of the wall is analyzed at various stages in the growth of the aneurysm. Increasing the wall stiffness alters the distribution of wall shear stresses and leads to an increase in their magnitude. The wall compliance is shown to have a more pronounced effect on non-axisymmetric aneurysms, which sustain large displacements. The overall movement of the aneurysm models increases the three-dimensionality of the flow.

  20. [Review of pre- and post-treatment multidetector computed tomography findings in abdominal aortic aneurysms].

    PubMed

    Casula, E; Lonjedo, E; Cerverón, M J; Ruiz, A; Gómez, J

    2014-01-01

    The increase in the frequency of abdominal aortic aneurysms (AAA) and the widely accepted use of endovascular aneurysm repair (EVAR) as a first-line treatment or as an alternative to conventional surgery make it necessary for radiologists to have thorough knowledge of the pre- and post-treatment findings. The high image quality provided by multidetector computed tomography (MDCT) enables CT angiography to play a fundamental role in the study of AAA and in planning treatment. The objective of this article is to review the cases of AAA in which CT angiography was the main imaging technique, so that radiologists will be able to detect the signs related to this disease, to diagnose it, to plan treatment, and to detect complications in the postoperative period.

  1. Discovery of Cathepsin S Inhibitor LY3000328 for the Treatment of Abdominal Aortic Aneurysm

    PubMed Central

    2014-01-01

    Cathepsin S (Cat S) plays an important role in many pathological conditions, including abdominal aortic aneurysm (AAA). Inhibition of Cat S may provide a new treatment for AAA. To date, several classes of Cat S inhibitors have been reported, many of which form covalent interactions with the active site Cys25. Herein, we report the discovery of a novel series of noncovalent inhibitors of Cat S through a medium-throughput focused cassette screen and the optimization of the resulting hits. Structure-based optimization efforts led to Cat S inhibitors such as 5 and 9 with greatly improved potency and drug disposition properties. This series of compounds binds to the S2 and S3 subsites without interacting with the active site Cys25. On the basis of in vitro potency, selectivity, and efficacy in a CaCl2-induced AAA in vivo model, 5 (LY3000328) was selected for clinical development. PMID:25313327

  2. Treatment of Type II Endoleaks After Endovascular Repair of Abdominal Aortic Aneurysms: Transcaval Approach

    SciTech Connect

    Mansueto, Giancarlo Cenzi, Daniela; D'Onofrio, Mirko; Petrella, Enrico; Gumbs, Andrew A.; Mucelli, Roberto Pozzi

    2005-06-15

    The purpose of the note is to describe a new technique for type II endoleak treatment, using an alternative approach through femoral venous access. Three patients who developed type II endoleak after endovascular repair of abdominal aortic aneurysm were treated with direct transcaval puncture and embolization inside the aneurysm sac. The detailed technique is described. All patients were treated without any complications and discharged 48 hours after the treatment. At 1 month follow-up the computed tomograph scan did not show a recurrence of a type II endoleak. The management of patients with type II endoleak is a controversial issue and different techniques have been proposed. We suggest an alternative technique for type II endoleak treatment. The feasibility and the advantages of this approach can offer new possibilities for the diagnosis as well as for the treatment of this complication.

  3. Three-band decomposition analysis in multiscale FSI models of abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Nestola, Maria G. C.; Gizzi, Alessio; Cherubini, Christian; Filippi, Simonetta

    2016-07-01

    Computational modeling plays an important role in biology and medicine to assess the effects of hemodynamic alterations in the onset and development of vascular pathologies. Synthetic analytic indices are of primary importance for a reliable and effective a priori identification of the risk. In this scenario, we propose a multiscale fluid-structure interaction (FSI) modeling approach of hemodynamic flows, extending the recently introduced three-band decomposition (TBD) analysis for moving domains. A quantitative comparison is performed with respect to the most common hemodynamic risk indicators in a systematic manner. We demonstrate the reliability of the TBD methodology also for deformable domains by assuming a hyperelastic formulation of the arterial wall and a Newtonian approximation of the blood flow. Numerical simulations are performed for physiologic and pathologic axially symmetric geometry models with particular attention to abdominal aortic aneurysms (AAAs). Risk assessment, limitations and perspectives are finally discussed.

  4. [Thoraco-abdominal aortic replacement in chronic phase in a patient with temporary paraplegia after Stanford B acute dissection].

    PubMed

    Takahashi, Goro; Hata, Masaki; Tabayashi, Koichi

    2013-07-01

    A 42-year-old man underwent was performed with thoraco-abdominal aneurysm replacement accompaniedy with reconstruction of abdominal branches and intercostal arteries. Eighteen months before, he had suffered from Stanford already been cured with paraplegia on being type B acute aortic dissection combined with paraplegia. When paraplegia had been occurred, cerebrospinal fluid drainage was had been performed promptly, and 4 days later, neurologic deficit was disappeared in 1 day. During the thoraco-abdominal aortic operation, cerebrospinal fluid drainage was performed done again. After the operation, paraplegia did was not occurred and he did not feel somewhat wrong with his legs. He was discharged from hospital on foot by himself. This case showed the efficacy of cerebral spinal fluid drainage for not only both with the prevention but also and treatment of paraplegia.

  5. A rare but potentially lethal case of tuberculous aortic aneurysm presenting with repeated attacks of abdominal pain.

    PubMed

    Hung, Yao-Min; Chang, Yun-Te; Wang, Jyh-Seng; Wang, Paul Yung-Pou; Wann, Shue-Ren

    2015-01-01

    Tuberculous aortic aneurysm is an extremely rare disease with a high mortality rate. The clinical features of this condition are highly variable, ranging from asymptomatic with or without constitutional symptoms, abdominal pain to frank rupture, bleeding and shock. We herein report the case of a 56-year-old man with a large tuberculous mycotic aneurysm in the abdominal aorta with an initial presentation of repeated attacks of abdominal pain lasting for several months. Due to the vague nature of the initial symptoms, tuberculous aortic aneurysms may take several months to diagnose. This case highlights the importance of having a high index of suspicion and providing timely surgery for this rare but potentially lethal disease.

  6. Results of Open and Endovascular Abdominal Aortic Aneurysm Repair According to the E-PASS Score

    PubMed Central

    Menezes, Fábio Hüsemann; Ferrarezi, Bárbara; de Souza, Moisés Amâncio; Cosme, Susyanne Lavor; Molinari, Giovani José Dal Poggetto

    2016-01-01

    Introduction: Endovascular repair (EVAR) of abdominal aortic aneurysm has become the standard of care due to a lower 30-day mortality, a lower morbidity, shorter hospital stay and a quicker recovery. The role of open repair (OR) and to whom this type of operation should be offered is subject to discussion. Objective: To present a single center experience on the repair of abdominal aortic aneurysm, comparing the results of open and endovascular repairs. Methods: Retrospective cross-sectional observational study including 286 patients submitted to OR and 91 patients submitted to EVAR. The mean follow-up for the OR group was 66 months and for the EVAR group was 39 months. Results: The overall mortality was 11.89% for OR and 7.69% for EVAR (P=0.263), EVAR presented a death relative risk of 0.647. It was also found a lower intraoperative bleeding for EVAR (OR=1417.48±1180.42 mL versus EVAR=597.80±488.81 mL, P<0.0002) and a shorter operative time for endovascular repair (OR=4.40±1.08 hours versus EVAR=3.58±1.26 hours, P<0.003). The postoperative complications presented no statistical difference between groups (OR=29.03% versus EVAR=25.27%, P=0.35). Conclusion: EVAR presents a better short term outcome than OR in all classes of physiologic risk. In order to train future vascular surgeons on OR, only young and healthy patients, who carry a very low risk of adverse events, should be selected, aiming at the long term durability of the procedure. PMID:27074271

  7. Induction of histone deacetylases (HDACs) in human abdominal aortic aneurysm: therapeutic potential of HDAC inhibitors

    PubMed Central

    Galán, María; Varona, Saray; Orriols, Mar; Rodríguez, José Antonio; Aguiló, Silvia; Dilmé, Jaume; Camacho, Mercedes; Martínez-González, José; Rodriguez, Cristina

    2016-01-01

    ABSTRACT Clinical management of abdominal aortic aneurysm (AAA) is currently limited to elective surgical repair because an effective pharmacotherapy is still awaited. Inhibition of histone deacetylase (HDAC) activity could be a promising therapeutic option in cardiovascular diseases. We aimed to characterise HDAC expression in human AAA and to evaluate the therapeutic potential of class I and IIa HDAC inhibitors in the AAA model of angiotensin II (Ang II)-infused apolipoprotein-E-deficient (ApoE−/−) mice. Real-time PCR, western blot and immunohistochemistry evidenced an increased expression of HDACs 1, 2 (both class I), 4 and 7 (both class IIa) in abdominal aorta samples from patients undergoing AAA open repair (n=22) compared with those from donors (n=14). Aortic aneurysms from Ang-II-infused ApoE−/− mice exhibited a similar HDAC expression profile. In these animals, treatment with a class I HDAC inhibitor (MS-275) or a class IIa inhibitor (MC-1568) improved survival, reduced the incidence and severity of AAA and limited aneurysmal expansion evaluated by Doppler ultrasonography. These beneficial effects were more potent in MC-1568-treated mice. The disorganisation of elastin and collagen fibres and lymphocyte and macrophage infiltration were effectively reduced by both inhibitors. Additionally, HDAC inhibition attenuated the exacerbated expression of pro-inflammatory markers and the increase in metalloproteinase-2 and -9 activity induced by Ang II in this model. Therefore, our data evidence that HDAC expression is deregulated in human AAA and that class-selective HDAC inhibitors limit aneurysm expansion in an AAA mouse model. New-generation HDAC inhibitors represent a promising therapeutic approach to overcome human aneurysm progression. PMID:26989193

  8. Nifedipine attenuation of abdominal aortic aneurysm in hypertensive and non-hypertensive mice: Mechanisms and implications.

    PubMed

    Miao, Xiao Niu; Siu, Kin Lung; Cai, Hua

    2015-10-01

    Rupture of abdominal aortic aneurysm (AAA) is a lethal event. No oral medicine has been available to prevent or treat AAA. We have recently identified a novel mechanism of eNOS uncoupling by which AAA develops, in angiotensin II (Ang II) infused hyperphenylalaninemia 1 (hph-1) mice. Using this unique model we investigated effects on AAA formation of the L-type calcium channel blocker nifedipine, in view of the unclear relationship between hypertension and AAA, and unclear mechanisms of aneurysm protective effects of some blood pressure lowering drugs. Six-month old hph-1 mice were infused with Ang II (0.7 mg/kg/day) for 2 weeks, and fed nifedipine chow at two different doses (5 and 20 mg/kg/day). While the high dose of nifedipine reduced blood pressure, the lower dose had no effect. Interestingly, the incidence rate of AAA dropped from 71% to 7 and 12.5% for low and high dose nifedipine, respectively. Expansion of abdominal aorta, determined by ultrasound imaging, was abolished by both doses of nifedipine, which recoupled eNOS completely to improve NO bioavailability. Both also abrogated aortic superoxide production. Of note, Ang II activation of NADPH oxidase in vascular smooth muscle cells and endothelial cells, known to uncouple eNOS, was also attenuated by nifedipine. Although low dose was a sub-pressor while the high dose reduced blood pressure via inhibition of calcium channels, both doses were highly effective in preventing AAA by preserving eNOS coupling activity to eliminate sustained oxidative stress from uncoupled eNOS. These data demonstrate that oral treatment of nifedipine is highly effective in preserving eNOS function to attenuate AAA formation. Nifedipine may be used for AAA prevention either at low dose in AAA risk group, or at high dose in patients with co-existing hypertension.

  9. Nifedipine Attenuation of Abdominal Aortic Aneurysm in Hypertensive and non-Hypertensive Mice: Mechanisms and Implications

    PubMed Central

    Miao, Xiao Niu; Siu, Kin Lung; Cai, Hua

    2015-01-01

    Rupture of abdominal aortic aneurysm (AAA) is a lethal event. No oral medicine has been available to prevent or treat AAA. We have recently identified a novel mechanism of eNOS uncoupling by which AAA develops, in Angiotensin II (Ang II) infused hyperphenylalaninemia 1 (hph-1) mice. Using this unique model we investigated effects on AAA formation of the L-type calcium channel blocker nifedipine, in view of the unclear relationship between hypertension and AAA, and unclear mechanisms of aneurysm protective effects of some blood pressure lowering drugs. Six-month old hph-1 mice were infused with Ang II (0.7 mg/kg/day) for 2 weeks, and fed nifedipine chow at two different doses (5 and 20 mg/kg/day). While the high dose of nifedipine reduced blood pressure, the lower dose had no effect. Interestingly, the incidence rate of AAA dropped from 71% to 7 and 12.5% for low and high dose nifedipine, respectively. Expansion of abdominal aorta, determined by ultrasound imaging, was abolished by both doses of nifedipine, which recoupled eNOS completely to improve NO bioavailability. Both also abrogated aortic superoxide production. Of note, Ang II activation of NADPH oxidase in vascular smooth muscle cells and endothelial cells, known to uncouple eNOS, was also attenuated by nifedipine. Although low dose was a sub-pressor while the high dose reduced blood pressure via inhibition of calcium channels, both doses were highly effective in preventing AAA by preserving eNOS coupling activity to eliminate sustained oxidative stress from uncoupled eNOS. These data demonstrate that oral treatment of nifedipine is highly effective in preserving eNOS function to attenuate AAA formation. Nifedipine may be used for AAA prevention either at low dose to AAA risk group, or at high dose to patients with co-existing hypertension. PMID:26254182

  10. Toward a noninvasive subject-specific estimation of abdominal aortic pressure.

    PubMed

    Thore, Carl-Johan; Stålhand, Jonas; Karlsson, Matts

    2008-09-01

    A method for estimation of central arterial pressure based on linear one-dimensional wave propagation theory is presented in this paper. The equations are applied to a distributed model of the arterial tree, truncated by three-element windkessels. To reflect individual differences in the properties of the arterial trees, we pose a minimization problem from which individual parameters are identified. The idea is to take a measured waveform in a peripheral artery and use it as input to the model. The model subsequently predicts the corresponding waveform in another peripheral artery in which a measurement has also been made, and the arterial tree model is then calibrated in such a way that the computed waveform matches its measured counterpart. For the purpose of validation, invasively recorded abdominal aortic, brachial, and femoral pressures in nine healthy subjects are used. The results show that the proposed method estimates the abdominal aortic pressure wave with good accuracy. The root mean square error (RMSE) of the estimated waveforms was 1.61 +/- 0.73 mmHg, whereas the errors in systolic and pulse pressure were 2.32 +/- 1.74 and 3.73 +/- 2.04 mmHg, respectively. These results are compared with another recently proposed method based on a signal processing technique, and it is shown that our method yields a significantly (P < 0.01) lower RMSE. With more extensive validation, the method may eventually be used in clinical practice to provide detailed, almost individual, specific information as a valuable basis for decision making.

  11. Regulatory T cells in human and angiotensin II-induced mouse abdominal aortic aneurysms

    PubMed Central

    Zhou, Yi; Wu, Wenxue; Lindholt, Jes S.; Sukhova, Galina K.; Libby, Peter; Yu, Xueqing; Shi, Guo-Ping

    2015-01-01

    Aims Regulatory T cells (Tregs) protect mice from angiotensin II (Ang-II)-induced abdominal aortic aneurysms (AAA). This study tested whether AAA patients are Treg-insufficient and the Treg molecular mechanisms that control AAA pathogenesis. Methods and results ELISA determined the Foxp3 concentration in blood cell lysates from 485 AAA patients and 204 age- and sex-matched controls. AAA patients exhibited lower blood cell Foxp3 expression than controls (P < 0.0001). Pearson's correlation test demonstrated a significant but negative correlation between Foxp3 and AAA annual expansion rate before (r = –0.147, P = 0.007) and after (r = –0.153, P = 0.006) adjustment for AAA risk factors. AAA in apolipoprotein E-deficient (Apoe–/–) mice that received different doses of Ang-II exhibited a negative correlation of lesion Foxp3+ Treg numbers with AAA size (r = –0.883, P < 0.0001). Adoptive transfer of Tregs from wild-type (WT) and IL10-deficient (Il10–/–) mice increased AAA lesion Treg content, but only WT mice Tregs reduced AAA size, AAA incidence, blood pressure, lesion macrophage and CD4+ and CD8+ T-cell accumulation, and angiogenesis with concurrent increase of lesion collagen content. Both AAA lesion immunostaining and plasma ELISA demonstrated that adoptive transfer of WT Tregs, but not Il10–/– Tregs, reduced the expression of MCP-1. In vitro cell culture and aortic ring assay demonstrated that only Tregs from WT mice, but not those from Il10–/– mice, reduced macrophage MCP-1 secretion, macrophage and vascular cell protease expression and activity, and aortic ring microvessel formation. Conclusion This study supports a protective role of Tregs in human and experimental AAA by releasing IL10 to suppress inflammatory cell chemotaxis, arterial wall remodelling, and angiogenesis. PMID:25824145

  12. An abdominal aortic aneurysm segmentation method: level set with region and statistical information.

    PubMed

    Zhuge, Feng; Rubin, Geoffrey D; Sun, Shaohua; Napel, Sandy

    2006-05-01

    We present a system for segmenting the human aortic aneurysm in CT angiograms (CTA), which, in turn, allows measurements of volume and morphological aspects useful for treatment planning. The system estimates a rough "initial surface," and then refines it using a level set segmentation scheme augmented with two external analyzers: The global region analyzer, which incorporates a priori knowledge of the intensity, volume, and shape of the aorta and other structures, and the local feature analyzer, which uses voxel location, intensity, and texture features to train and drive a support vector machine classifier. Each analyzer outputs a value that corresponds to the likelihood that a given voxel is part of the aneurysm, which is used during level set iteration to control the evolution of the surface. We tested our system using a database of 20 CTA scans of patients with aortic aneurysms. The mean and worst case values of volume overlap, volume error, mean distance error, and maximum distance error relative to human tracing were 95.3% +/- 1.4% (s.d.); worst case = 92.9%, 3.5% +/- 2.5% (s.d.); worst case = 7.0%, 0.6 +/- 0.2 mm (s.d.); worst case = 1.0 mm, and 5.2 +/- 2.3 mm (s.d.); worst case = 9.6 mm, respectively. When implemented on a 2.8 GHz Pentium IV personal computer, the mean time required for segmentation was 7.4 +/- 3.6 min (s.d.). We also performed experiments that suggest that our method is insensitive to parameter changes within 10% of their experimentally determined values. This preliminary study proves feasibility for an accurate, precise, and robust system for segmentation of the abdominal aneurysm from CTA data, and may be of benefit to patients with aortic aneurysms.

  13. Autoradiography screening of potential positron emission tomography tracers for asymptomatic abdominal aortic aneurysms

    PubMed Central

    Estrada, Sergio; Hall, Håkan; Wanhainen, Anders; Björck, Martin; Sörensen, Jens; Antoni, Gunnar

    2014-01-01

    Objective The aetiology and early pathophysiological mechanisms of aortic aneurysm formation are still unknown and challenging to study in vivo. Positron emission tomography (PET) is a potentially valuable instrument for non-invasive in vivo pathophysiological studies. No specific tracer to identify the pathophysiological process of aneurysmal dilatation is yet available, however. The aim of this study was to explore if different PET tracers could be useful to image aneurysmal disease. Methods and results Human aneurysmal aortic tissue, collected during elective resection of abdominal aortic aneurysm (AAA) of asymptomatic patients, was investigated in vitro by means of autoradiography with [68Ga]CRP-binder targeting C-reactive protein, [11C]DAA1106 targeting translocator protein (18 kDa), [11C]D-deprenyl with unknown target receptor, [11C]deuterium-L-deprenyl targeting astrocytes, [18F]fluciclatide targeting integrin αVβ3, [68Ga]IMP461 and bi-specific antibody TF2 052107 targeting carcinoembryonic antigen, [18F]F-metomidate targeting mitochondrial cytochrome P-450 species in the adrenal cortex, and [18F]vorozole targeting aromatase. Of the investigated tracers, only [18F]fluciclatide exhibited specific binding, whereas the other PET tracers failed to show specific uptake in the investigated tissue and are probably not useful for the intended purpose. Conclusion It seems likely that αVβ3 integrin expression in AAA can be visualized with PET and that the αVβ3 selective tracer, [18F]fluciclatide, may be suitable for in vivo molecular imaging of asymptomatic AAA. Additional evaluation of [18F]fluciclatide and αVβ3 integrin expression in AAA will be performed in vitro as well as in vivo. PMID:24555564

  14. An abdominal aortic aneurysm segmentation method: Level set with region and statistical information

    SciTech Connect

    Zhuge Feng; Rubin, Geoffrey D.; Sun Shaohua; Napel, Sandy

    2006-05-15

    We present a system for segmenting the human aortic aneurysm in CT angiograms (CTA), which, in turn, allows measurements of volume and morphological aspects useful for treatment planning. The system estimates a rough 'initial surface', and then refines it using a level set segmentation scheme augmented with two external analyzers: The global region analyzer, which incorporates a priori knowledge of the intensity, volume, and shape of the aorta and other structures, and the local feature analyzer, which uses voxel location, intensity, and texture features to train and drive a support vector machine classifier. Each analyzer outputs a value that corresponds to the likelihood that a given voxel is part of the aneurysm, which is used during level set iteration to control the evolution of the surface. We tested our system using a database of 20 CTA scans of patients with aortic aneurysms. The mean and worst case values of volume overlap, volume error, mean distance error, and maximum distance error relative to human tracing were 95.3%{+-}1.4% (s.d.); worst case=92.9%, 3.5%{+-}2.5% (s.d.); worst case=7.0%, 0.6{+-}0.2 mm (s.d.); worst case=1.0 mm, and 5.2{+-}2.3mm (s.d.); worstcase=9.6 mm, respectively. When implemented on a 2.8 GHz Pentium IV personal computer, the mean time required for segmentation was 7.4{+-}3.6min (s.d.). We also performed experiments that suggest that our method is insensitive to parameter changes within 10% of their experimentally determined values. This preliminary study proves feasibility for an accurate, precise, and robust system for segmentation of the abdominal aneurysm from CTA data, and may be of benefit to patients with aortic aneurysms.

  15. Abdominal Aortic Diameter and Vascular Atherosclerosis: The Multi-Ethnic Study of Atherosclerosis

    PubMed Central

    Laughlin, Gail A.; Allison, Matthew A.; Jensky, Nicole; Aboyans, Victor; Wong, Nathan D.; Detrano, Robert; Criqui, Michael H.

    2011-01-01

    Objectives To gain insight into early mechanisms of aortic widening, we examined associations between the diameter of the abdominal aorta (AD) and cardiovascular disease (CVD) risk factors and biomarkers, as well as measures of subclinical atherosclerosis, in a multi-ethnic population. Design Cross-sectional cohort Methods A total of 1926 participants (mean age 62, 50% women) underwent chest and abdomen scanning by computed tomography, ultrasound of the carotid arteries, and CVD risk factor assessment. AD was measured 5 cm above and at the bifurcation. Results In a model containing traditional CVD risk factors, biomarkers and ethnicity, only age (standardized β=0.97), male sex (β=1.88), body surface area (standardized β=0.92), current smoking (β=0.42), D-dimer levels (β=0.19) and hypertension (β=0.53) were independently and significantly associated with increasing AD (in mm) at the bifurcation; use of cholesterol-lowering medications predicted smaller AD (β=-0.70) (P<.01 for all). These findings were similar for AD 5 cm above the bifurcation with one exception: compared to Caucasian-Americans, Americans of Chinese, African and Hispanic descent had significantly smaller AD 5 cm above the bifurcation (β's= -0.59, -0.49, and -0.52, respectively, all P<.01), whereas AD at the bifurcation did not differ by ethnicity. Physical activity, alcohol consumption, diabetes and levels of IL-6, CRP and homocysteine were not independently associated with AD. Higher aortic and coronary artery calcium burden, but not common carotid artery intima-media thickness, were independently, but modestly (β=0.11 to 0.19), associated with larger AD. Conclusions Incremental widening of the aortic diameter shared some, but not all, risk factors for occlusive vascular disease. PMID:21236707

  16. Oral administration of diferuloylmethane (curcumin) suppresses proinflammatory cytokines and destructive connective tissue remodeling in experimental abdominal aortic aneurysms.

    PubMed

    Parodi, Federico E; Mao, Dongli; Ennis, Terri L; Pagano, Monica B; Thompson, Robert W

    2006-05-01

    Chronic transmural inflammation and proteolytic destruction of medial elastin are key mechanisms in the development of abdominal aortic aneurysms (AAAs). Diferuloylmethane (curcumin) is a major component of the food additive tumeric, which has been shown to have anti-inflammatory properties. To determine if ingestion of curcumin influences aneurysmal degeneration, C57Bl/6 mice underwent transient elastase perfusion of the abdominal aorta to induce the development of AAAs, followed by daily oral gavage with 100 mg/kg curcumin (n = 36) or water alone (n = 31). By 14 days, mice in the control group developed a mean increase in aortic diameter of 162.8 +/- 4.6% along with a dense mononuclear inflammation and destruction of medial elastin. By comparison, the mean increase in aortic diameter in the curcumin-treated group was only 133.2 +/- 5.2% (p < 0.0001). Although aortic wall inflammation was similar between the groups, the structural integrity of medial elastin was significantly greater in curcumin-treated mice. Curcumin-treated mice also exhibited relative decreases in aortic tissue activator protein-1 and nuclear factor kappaB DNA binding activities and significantly lower aortic tissue concentrations of interleukin-1beta (IL-1beta), IL-6, monocyte chemoattractant protein-1, and matrix metalloproteinase-9 (all p < 0.05). These data demonstrate for the first time that oral administration of curcumin can suppress the development of experimental AAAs, along with structural preservation of medial elastin fibers and reduced aortic wall expression of several cytokines, chemokines, and proteinases known to mediate aneurysmal degeneration. The possibility that dietary ingestion of curcumin may have a beneficial effect in degenerative aortic aneurysms warrants further consideration.

  17. Perspectives on stem cell-based elastic matrix regenerative therapies for abdominal aortic aneurysms.

    PubMed

    Bashur, Chris A; Rao, Raj R; Ramamurthi, Anand

    2013-06-01

    Abdominal aortic aneurysms (AAAs) are potentially fatal conditions that are characterized by decreased flexibility of the aortic wall due to proteolytic loss of the structural matrix. This leads to their gradual weakening and ultimate rupture. Drug-based inhibition of proteolytic enzymes may provide a nonsurgical treatment alternative for growing AAAs, although it might at best be sufficient to slow their growth. Regenerative repair of disrupted elastic matrix is required if regression of AAAs to a healthy state is to be achieved. Terminally differentiated adult and diseased vascular cells are poorly capable of affecting such regenerative repair. In this context, stem cells and their smooth muscle cell-like derivatives may represent alternate cell sources for regenerative AAA cell therapies. This article examines the pros and cons of using different autologous stem cell sources for AAA therapy, the requirements they must fulfill to provide therapeutic benefit, and the current progress toward characterizing the cells' ability to synthesize elastin, assemble elastic matrix structures, and influence the regenerative potential of diseased vascular cell types. The article also provides a detailed perspective on the limitations, uncertainties, and challenges that will need to be overcome or circumvented to translate current strategies for stem cell use into clinically viable AAA therapies. These therapies will provide a much needed nonsurgical treatment option for the rapidly growing, high-risk, and vulnerable elderly demographic.

  18. Plasma cytokine levels and risks of abdominal aortic aneurysms: A population-based prospective cohort study

    PubMed Central

    Liao, Mengyang; Liu, Cong-Lin; Lv, Bing-Jie; Zhang, Jin-Ying; Cheng, Longxian; Cheng, Xiang; Lindholt, Jes S.; Rasmussen, Lars M.; Shi, Guo-Ping

    2015-01-01

    Background Abdominal aortic aneurysm (AAA) is characterized by inflammatory cell accumulation in AAA lesions that produce inflammatory cytokines and advance its pathogenesis. Peripheral cytokines may predict the degree or risk of AAA. Methods and Results ELISA determined plasma interleukin-6 (IL6), IL10, IL17A, IFN-γ, and C-reactive protein (CRP) from 476 AAA patients and 200 controls. AAA patients had lower IL6, IFN-γ, IL10, IL17A, and higher CRP than controls. IL10 correlated positively with IFN-γ, IL17A, or IL6, but not CRP in control or AAA populations. IL10 associated negatively with systolic blood pressure, whereas CRP associated positively with diastolic blood pressure and body mass index. CRP was an independent AAA risk factor and correlated positively with aortic diameters before and after adjustments for other risk factors. IFN-γ, IL17A, and CRP correlated positively with cross-sectional AAA area after adjustment. IL10 correlated positively with AAA growth rate before and after adjustment. AAA patients with CRP levels above the median doubled the risk of death. Conclusions Reduced IFN-γ, IL10, and IL17A in AAA patients, positive correlations of IFN-γ and IL17A with cross-sectional AAA area, IL10 with AAA growth rate, and IL10 with IFN-γ and IL17A suggest combined Th1, Th2, and Th17 immune responses in human AAAs. PMID:25856542

  19. Association of Colony Forming Units with Coronary Artery and Abdominal Aortic Calcification

    PubMed Central

    Cheng, Susan; Cohen, Kenneth S.; Shaw, Stanley Y.; Larson, Martin G.; Hwang, Shih-Jen; McCabe, Elizabeth L.; Martin, Roderick P.; Klein, Rachael J.; Hashmi, Basma; Hoffmann, Udo; Fox, Caroline S.; Vasan, Ramachandran S.; O’Donnell, Christopher J.; Wang, Thomas J.

    2010-01-01

    Background Certain bone marrow-derived cell populations, termed endothelial progenitor cells (EPCs), have been reported to possess angiogenic activity. Experimental data suggest that depletion of these angiogenic cell populations may promote atherogenesis, but limited data are available regarding their relation to subclinical atherosclerotic cardiovascular disease in humans. Methods and Results We studied 889 participants of the Framingham Heart Study who were free of clinically apparent cardiovascular disease (mean age, 65 years; 55% women). Participants underwent EPC phenotyping using an early outgrowth colony forming unit (CFU) assay and cell surface markers. Participants also underwent non-contrast multidetector computed tomography to assess the presence of subclinical atherosclerosis, as reflected by burden of coronary artery calcification (CAC) and abdominal aortic calcification (AAC). In this study sample, we examined the association of EPC-related phenotypes with both CAC and AAC. Across decreasing tertiles of CFU, there was a progressive increase in median CAC and AAC scores. In multivariable analyses adjusting for traditional cardiovascular risk factors, each standard deviation increase in CFU was associated with an approximately 16% decrease in CAC (P=0.02) and 17% decrease in AAC (P=0.03). In contrast, neither CD34+/KDR+ nor CD34+ variation were associated with significant differences in coronary or aortic calcification. Conclusion In this large, community-based sample of men and women, lower CFU number was associated with a higher burden of subclinical atherosclerosis in the coronary arteries and aorta. Decreased angiogenic potential could contribute to the development of atherosclerosis in humans. PMID:20823386

  20. Abdominal aortic endograft infection: report of two cases and review of the literature.

    PubMed

    Veraldi, Gian Franco; Genco, Bruno; Minicozzi, Annamaria; Zecchinelli, Marco Paolo; Segattini, Christian; Momo, Rostand Emmanuel; Pacca, Rosario

    2009-01-01

    Endovascular prosthesis infection after exclusion of an abdominal aortic aneurysm is a rare, dramatic event and its diagnosis and treatment are extremely complex. This particular complication has been less well explored in the literature than others such as endoleaks, migration or stent rupture. The incidence of aorto-iliac stent-graft infection is almost 0.7%, while the infection rate in open surgery varies from 0.6% to 3%. Moreover, the infection can be early when it arises within 4 months of the implant or late when it arises after 4 months. Since 1991 only 94 cases of endograft infections have been reported in the world literature, to which our two cases need to be added, making a total of 96 cases. The first of our patients was diagnosed with an early infection that was successfully treated by explanting the infected graft followed by aortic reconstruction with a homograft. Six months after the operation the patient died of cardiac failure. The second case was a late infection which developed 8 years after the first intervention in a patient with chronic renal failure treated with dialytic therapy. After aneurysmectomy and stent-graft removal, a bifurcated dacron silver graft was implanted. The patient died of cardiogenic shock 40 days after surgery. The surgical treatment of this serious complication is associated with high perioperative morbidity and mortality rates and requires very careful planning of the operation.

  1. Endovascular Management of Ruptured Abdominal Aortic Aneurysms: An 8-year Single-Centre Experience

    SciTech Connect

    Gerassimidis, Thomas S.; Karkos, Christos D. Karamanos, Dimitrios G.; Papazoglou, Konstantinos O.; Papadimitriou, Dimitrios N.; Demiropoulos, Filippos P.; Malkotsis, Dimitrios P.; Kamparoudis, Apostolos G.

    2009-03-15

    We aimed to review our experience with the endovascular treatment of ruptured abdominal aortic aneurysm (RAAA). During an 8-year period, 69 patients with a RAAA presented to our department; 67 underwent assessment by computed axial tomography, and 2 died on arrival before any evaluation was possible. A total of 42 patients (63%) were suitable for stent-grafting, and all but 1 (c-arm failure) proceeded to endovascular repair. Of these, 27 underwent surgery with local anaesthesia; 3 did so under general anaesthesia; and a further 11 procedures were commenced with the patient under local anaesthesia and then converted to general anaesthesia. A total of 28 bifurcated and 14 aorto-uni-iliac stent-grafts were implanted. Aortic occlusion balloons were used in 2 (5%) patients. The in-hospital and the 30-day mortality rates were 36% and 41%, respectively. After surgery, 21 complications were encountered in 17 patients. Two patients required reintervention during their hospital stay (1 type I endoleak and 1 limb occlusion). During the follow-up (median 730 days [range 90 to 580 days]), the 1-year and 5-year cumulative survival probabilities were 53% (SE 7.9%) and 50% (SE 8.0%), respectively. Three reinterventions were necessary during follow-up (2 type I endoleaks and 1 graft occlusion). We conclude that endovascular treatment is feasible in the emergency setting, and the early experience is promising. Whether such an approach is superior to open surgery remains to be determined.

  2. Endoleak Assessment Using Computational Fluid Dynamics and Image Processing Methods in Stented Abdominal Aortic Aneurysm Models

    PubMed Central

    Lu, Yueh-Hsun; Mani, Karthick; Panigrahi, Bivas; Hsu, Wen-Tang

    2016-01-01

    Endovascular aortic aneurysm repair (EVAR) is a predominant surgical procedure to reduce the risk of aneurysm rupture in abdominal aortic aneurysm (AAA) patients. Endoleak formation, which eventually requires additional surgical reoperation, is a major EVAR complication. Understanding the etiology and evolution of endoleak from the hemodynamic perspective is crucial to advancing the current posttreatments for AAA patients who underwent EVAR. Therefore, a comprehensive flow assessment was performed to investigate the relationship between endoleak and its surrounding pathological flow fields through computational fluid dynamics and image processing. Six patient-specific models were reconstructed, and the associated hemodynamics in these models was quantified three-dimensionally to calculate wall stress. To provide a high degree of clinical relevance, the mechanical stress distribution calculated from the models was compared with the endoleak positions identified from the computed tomography images of patients through a series of imaging processing methods. An endoleak possibly forms in a location with high local wall stress. An improved stent graft (SG) structure is conceived accordingly by increasing the mechanical strength of the SG at peak wall stress locations. The presented analytical paradigm, as well as numerical analysis using patient-specific models, may be extended to other common human cardiovascular surgeries. PMID:27660648

  3. The Effect of Perioperative Ischemia and Reperfusion on Multiorgan Dysfunction following Abdominal Aortic Aneurysm Repair

    PubMed Central

    Katseni, Konstantina; Kotsis, Thomas; Dafnios, Nikolaos; Arapoglou, Vassilis; Kaparos, Georgios; Logothetis, Emmanuel; Karvouni, Eleni; Katsenis, Konstantinos

    2015-01-01

    Abdominal aortic aneurysms (AAAs) are relatively common and are potentially life-threatening medical problems. The aim of this review is to provide an overview of the effect of I/R injury on multiorgan failure following AAA repair. The PubMed, CINAHL, EMBASE, Medline, Cochrane Review, and Scopus databases were comprehensively searched for articles concerning the pathophysiology of I/R and its systemic effects. Cross-referencing was performed using the bibliographies from the articles obtained. Articles retrieved were restricted to those published in English. One of the most prominent characteristics of AAA open repair is the double physiological phenomenon of ischemia-reperfusion (I/R) that happens either at the time of clamping or following the aortic clamp removal. Ischemia-reperfusion injury causes significant pathophysiological disturbances to distant organs, increasing the possibility for postoperative multiorgan failure. Although tissue injury is mediated by diverse mechanisms, microvascular dysfunction seems to be the final outcome of I/R. PMID:26798637

  4. Automatic vessel extraction and abdominal aortic stent planning in multislice CT

    NASA Astrophysics Data System (ADS)

    Subramanyan, Krishna; Smith, Dava; Varma, Jay; Chandra, Shalabh

    2002-05-01

    The abdominal aorta is the most common site for an aneurysm, which may lead to hemorrhage and death, to develop. The aim of this study was to develop a semi-automated method to de-lineate the vessels and detect the center-line of these vessels to make measurements necessary for stent design from multi-detector computed tomograms. We developed a robust method of tracking the aortic vessel tree with branches from a user selected seed point along the vessel path using scale space approaches, central transformation measures, vessel direction findings, iterative corrections and a priori information in determining the vessel branches. Fifteen patients were scanned with contrast on Mx8000 CT scanner (Philips Medical Systems), with a 3.2 mm thickness, 1.5 mm slice spacing, and a stack of 512x512x320 volume data sets were reconstructed. The algorithm required an initial user input to locate the vessel seen in axial CT slice. Next, the automated image processing took approximately two minutes to compute the centerline and borders of the aortic vessel tree. The results between the manually and automatically generated vessel diameters were compared and statistics were computed. We observed our algorithm was consistent (less than 0.01 S.D) and similar (less than 0.1 S.D) to manual results.

  5. Endovascular Therapy of Ruptured Abdominal Aortic Aneurysm: Mid- and Long-Term Results

    SciTech Connect

    Kubin, Klaus Sodeck, Gottfried H.; Teufelsbauer, H.; Nowatschka, Bernd; Kretschmer, Georg; Lammer, Johannes; Schoder, Maria

    2008-05-15

    As an alternative to open aneurysm repair, emergency endovascular aortic repair (EVAR) has emerged as a promising technique for ruptured abdominal aortic aneurysm (rAAA) within the last decade. The aim of this retrospective study is to present early and late outcomes of patients treated with EVAR for rAAA. Twenty-two patients (5 women, 17 men; mean age, 74 years) underwent EVAR for rAAA between November 2000 and April 2006. Diagnostic multislice computed tomography angiography was performed prior to stent-graft repair to evaluate anatomical characteristics and for follow-up examinations. Periprocedural patient characteristics and technical settings were evaluated. Mortality rates, hospital stay, and early and late complications, within a mean follow-up time of 744 {+-} 480 days, were also assessed. Eight of 22 patients were hemodynamically unstable at admission. Stent-graft insertion was successful in all patients. The total early complication rate was 54%, resulting in a 30-day mortality rate of 23%. The median intensive care unit stay was 2 days (range, 2-48 days), and the median hospital stay was 16 days (range, 9-210 days). During the follow-up period, three patients suffered from stent-graft-related complications. The overall mortality rate in our study group was 36%. EVAR is an acceptable, minimally invasive treatment option in patients with acute rAAA, independent of the patient's general condition. Short- and long-term outcomes are definitely comparable to those with open surgical repair procedures.

  6. A Literature Review of the Numerical Analysis of Abdominal Aortic Aneurysms Treated with Endovascular Stent Grafts

    PubMed Central

    Roy, David; Kauffmann, Claude; Delorme, Sébastien; Lerouge, Sophie; Cloutier, Guy; Soulez, Gilles

    2012-01-01

    The purpose of this paper is to present the basic principles and relevant advances in the computational modeling of abdominal aortic aneurysms and endovascular aneurysm repair, providing the community with up-to-date state of the art in terms of numerical analysis and biomechanics. Frameworks describing the mechanical behavior of the aortic wall already exist. However, intraluminal thrombus nonhomogeneous structure and porosity still need to be well characterized. Also, although the morphology and mechanical properties of calcifications have been investigated, their effects on wall stresses remain controversial. Computational fluid dynamics usually assumes a rigid artery wall, whereas fluid-structure interaction accounts for artery compliance but is still challenging since arteries and blood have similar densities. We discuss alternatives to fluid-structure interaction based on dynamic medical images that address patient-specific hemodynamics and geometries. We describe initial stresses, elastic boundary conditions, and statistical strength for rupture risk assessment. Special emphasis is accorded to workflow development, from the conversion of medical images into finite element models, to the simulation of catheter-aorta interactions and stent-graft deployment. Our purpose is also to elaborate the key ingredients leading to virtual stenting and endovascular repair planning that could improve the procedure and stent-grafts. PMID:22997538

  7. Abdominal aortic stiffness as a marker of atherosclerosis in childhood-onset asthma: a case–control study

    PubMed Central

    Ülger, Zülal; Gülen, Figen; Özyürek, Ruhi Arif

    2015-01-01

    Summary Background Asthma is one of the chronic inflammatory diseases. It is known that chronic inflammation accelerates atherosclerosis. Abdominal aortic stiffness parameters can be used to detect the early development of atherosclerosis. Aim In this study, we aimed to evaluate abdominal aortic stiffness parameters in childhood-onset asthma compared with a control group. Methods In this cross-sectional, case–control study, we evaluated 50 patients with childhood-onset asthma, and 57 healthy children as controls. Patients with a diagnosis of asthma of at least three years’ duration were included in the study. Children with hypertension, hyperlipidaemia, diabetes, a history of smoking contact, or systemic disease were excluded. The study and control groups were evaluated with transthoracic echocardiography, and abdominal aorta diameters were measured. Using the measured data, abdominal aortic stiffness parameters (aortic distensibility: DIS, aortic strain: S, pressure strain elastic modulus: Ep, and pressure strain normalised by diastolic pressure: Ep*) were calculated. Statistical evaluation was done with the Student’s t-test, chisquared test and Pearson’s correlation test. Results The study group consisted of 50 children (24 female, 26 male) with asthma. According to the GINA guidelines, 26 of the patients had mild intermittant asthma, six had mild persistent asthma and 18 had intermediate persistent asthma. None of the patients had severe asthma. In 37 of the asthma patients, spIgE was positive and these patients were accepted as having atopic asthma; 27 of these patients received immunotherapy. We did not detect any differences between the study and control groups in terms of gender, age and body mass index. No differences were evident between the groups with regard to systolic and diastolic blood pressure, heart rate, blood cholesterol levels and respiratory function test parameters. There was no difference between the asthma and control groups in the

  8. Blockade of receptor for advanced glycation end products protects against systolic overload-induced heart failure after transverse aortic constriction in mice.

    PubMed

    Liu, Yu; Yu, Manli; Zhang, Zhigang; Yu, Yunhua; Chen, Qi; Zhang, Wei; Zhao, Xianxian

    2016-11-15

    Heart failure is the consequence of sustained, abnormal neurohormonal and mechanical stress and remains a leading cause of death worldwide. The aim of this work was to identify whether blockade of receptor for advanced glycation end products (RAGE) protected against systolic overload-induced heart failure and investigate the possible underlying mechanism. It was found that RAGE mRNA and protein expression was up-regulated in cardiac tissues from mice subjected to pressure overload by transverse aortic constriction (TAC). Importantly, inhibition of RAGE by treatment with soluble RAGE (sRAGE) or FPS-ZM1 (a high-affinity RAGE-specific inhibitor) for 8 weeks attenuated cardiac remodeling (including cardiac hypertrophy and fibrosis), and dysfunction in mice exposed to TAC. Furthermore, treatment of TAC mice with sRAGE or FPS-ZM1 enhanced phosphorylation of AMPK and reduced phosphorylation of mTOR and protein expression of NFκB p65 in cardiac tissues. In addition, treatment of TAC mice with sRAGE or FPS-ZM1 abated oxidative stress, attenuated endoplasmic reticulum stress, and suppressed inflammation in cardiac tissues. These data demonstrated the benefits of blocking RAGE on the progression of systolic overload-induced heart failure in mice, which was possibly through modulating AMPK/mTOR and NFκB pathways.

  9. Effects of wenxin keli on the action potential and L-type calcium current in rats with transverse aortic constriction-induced heart failure.

    PubMed

    Chen, Yu; Li, Yang; Guo, Lili; Chen, Wen; Zhao, Mingjing; Gao, Yonghong; Wu, Aiming; Lou, Lixia; Wang, Jie; Liu, Xiaoqiu; Xing, Yanwei

    2013-01-01

    Objective. We investigated the effects of WXKL on the action potential (AP) and the L-type calcium current (I Ca-L) in normal and hypertrophied myocytes. Methods. Forty male rats were randomly divided into two groups: the control group and the transverse aortic constriction- (TAC-) induced heart failure group. Cardiac hypertrophy was induced by TAC surgery, whereas the control group underwent a sham operation. Eight weeks after surgery, single cardiac ventricular myocytes were isolated from the hearts of the rats. The APs and I Ca-L were recorded using the whole-cell patch clamp technique. Results. The action potential duration (APD) of the TAC group was prolonged compared with the control group and was markedly shortened by WXKL treatment in a dose-dependent manner. The current densities of the I Ca-L in the TAC group treated with 5 g/L WXKL were significantly decreased compared with the TAC group. We also determined the effect of WXKL on the gating mechanism of the I Ca-L in the TAC group. We found that WXKL decreased the I Ca-L by accelerating the inactivation of the channels and delaying the recovery time from inactivation. Conclusions. The results suggest that WXKL affects the AP and blocked the I Ca-L, which ultimately resulted in the treatment of arrhythmias.

  10. Effects of Wenxin Keli on the Action Potential and L-Type Calcium Current in Rats with Transverse Aortic Constriction-Induced Heart Failure

    PubMed Central

    Chen, Yu; Li, Yang; Guo, Lili; Chen, Wen; Zhao, Mingjing; Gao, Yonghong; Wu, Aiming; Lou, Lixia; Wang, Jie; Liu, Xiaoqiu; Xing, Yanwei

    2013-01-01

    Objective. We investigated the effects of WXKL on the action potential (AP) and the L-type calcium current (ICa-L) in normal and hypertrophied myocytes. Methods. Forty male rats were randomly divided into two groups: the control group and the transverse aortic constriction- (TAC-) induced heart failure group. Cardiac hypertrophy was induced by TAC surgery, whereas the control group underwent a sham operation. Eight weeks after surgery, single cardiac ventricular myocytes were isolated from the hearts of the rats. The APs and ICa-L were recorded using the whole-cell patch clamp technique. Results. The action potential duration (APD) of the TAC group was prolonged compared with the control group and was markedly shortened by WXKL treatment in a dose-dependent manner. The current densities of the ICa-L in the TAC group treated with 5 g/L WXKL were significantly decreased compared with the TAC group. We also determined the effect of WXKL on the gating mechanism of the ICa-L in the TAC group. We found that WXKL decreased the ICa-L by accelerating the inactivation of the channels and delaying the recovery time from inactivation. Conclusions. The results suggest that WXKL affects the AP and blocked the ICa-L, which ultimately resulted in the treatment of arrhythmias. PMID:24319478

  11. Association of Coronary Aortic Calcium with Abdominal Aortic Calcium Detected on Lateral Dual Energy X-Ray Absorptiometry Spine Images

    PubMed Central

    Schousboe, John T.; Claflin, Diane; Barrett-Connor, Elizabeth

    2009-01-01

    The association of abdominal aortic calcium (AAC) on lateral spine bone densitometry with coronary artery calcium (CAC) has not been reported. We studied 33 men and 73 women who had CAC scored with electron beam computed tomography at the 8th visit of the Rancho Bernardo study and lateral spine dual energy x-ray absorptiometry (DXA) images fully evaluable for AAC done at the 9th study visit. The association between CAC level and AAC tertile was assessed by ordinal logistic regression. The odds ratio of having a higher level of CAC score for those in the top tertile of AAC score (24-point scale score ≥ 5) was 6.42 (95% C.I. 2.28 – 18.1) and on an 8-point scale (score ≥ 3) was 3.38 (95% C.I. 1.26 – 9.07), compared to those with AAC scores in the bottom tertiles, adjusted for age, sex, systolic blood pressure, total and high density lipoprotein (HDL) cholesterol, smoking status, and diabetes. A 24-point AAC score of ≥ 5 had a sensitivity of 65% and a specificity of 70% to detect a high CAC score (≥ 400 units). An 8-point AAC score ≥ 3 had a sensitivity of 45% and a specificity of 78%. In conclusion, a high level of AAC on lateral spine DXA is strongly associated with coronary artery disease and may be commonly encountered since bone densitometry is indicated in all women age ≥ 65 and all men age ≥ 70. Its presence should be reported to the patient's physician to identify and manage modifiable risk factors. PMID:19616658

  12. An Animal Model of Abdominal Aortic Aneurysm Created with Peritoneal Patch: Technique and Initial Results

    SciTech Connect

    Maynar, Manuel Hernandez, Javier; Sun Fei; Miguel, Carmen de; Crisostomo, Veronica; Uson, Jesus; Pineda, Luis-Fernando

    2003-04-15

    The purpose of this study was to develop an abdominal aortic aneurysm model that more closely resembles themorphology of human aneurysms with potential for further growth of the sac. An infrarenal abdominal aortic aneurysm (AAA) model was created with a double-layered peritoneal patch in 27 domestic swine. The patch,measuring in average from 6 to 12 cm in length and from 2 to 3 cm in width, was sutured to the edge of an aortotomy. Pre- and postsurgical digital subtraction aortograms (DSA) were obtained to document the appearance and dimensions of the aneurysm. All animals were followed with DSA for up to 5 months. Laparoscopic examination enhanced by the use of laparoscopic ultrasound was also carried out in 2 animals to assess the aneurysm at 30 and 60 days following surgery. Histological examination was performed on 4 animals. All the animals that underwent the surgical creation of the AAA survived the surgical procedure.Postsurgical DSA demonstrated the presence of the AAA in all animals,defined as more than 50% increase in diameter. The aneurysmal mean diameter increased from the baseline of 10.27 {+-} 1.24 to 16.69{+-} 2.29 mm immediately after surgery, to 27.6 {+-} 6.59 mm at 14 days, 32.45 {+-} 8.76 mm at 30 days (p <0.01), and subsequently decreased to 25.98 {+-} 3.75 mm at 60 days. A total of 15 animals died of aneurysmal rupture that occurred more frequently in the long aneurysms ({>=}6 cm in length) than the short aneurysms (<6 cm in length) during the first 2 weeks after surgery(p < 0.05). No rupture occurred beyond 16 days after surgery. Four animals survived and underwent 60-day angiographic follow-up. Laparoscopic follow-up showed strong pulses, a reddish external appearance and undetectable suture lines on the aneurysmal wall. On pathology, the patches were well incorporated into the aortic wall, the luminal wall appeared almost completely endothelialized, and cellular and matrix proliferation were noted in the aneurysmal wall. A reproducible

  13. Pathological Analysis of the Ruptured Vascular Wall of Hypoperfusion-induced Abdominal Aortic Aneurysm Animal Model.

    PubMed

    Kugo, Hirona; Zaima, Nobuhiro; Tanaka, Hiroki; Hashimoto, Keisuke; Miyamoto, Chie; Sawaragi, Ayaka; Urano, Tetsumei; Unno, Naoki; Moriyama, Tatsuya

    2017-04-04

    Abdominal aortic aneurysm (AAA) is a vascular disease that results in the gradual dilation of the abdominal aorta and has a high rupture-related mortality rate. However, the mechanism of AAA rupture remains unknown. In our previous study, we established a novel AAA animal model (hypoperfusion-induced AAA rat model) with spontaneous AAA rupture. Using the hypoperfusion-induced AAA rat model, we demonstrated that the abnormal appearance of adipocytes in the vascular wall is associated with AAA rupture. However, pathological analysis of the rupture area has not been performed because it is particularly difficult to identify the rupture point. In this study, we succeeded in obtaining samples from the rupture point and performed a histological analysis of the ruptured area in the vascular wall in the hypoperfusion-induced AAA rat model. Adipocytes were observed along the AAA-ruptured area of the vascular wall. In the areas around the adipocytes, macrophage infiltration and protein levels of matrix metalloproteinases 2 and 9 were significantly increased and collagen-positive areas were significantly decreased, as compared with areas without adipocytes. The AAA diameter was correlated with the number of adipocytes in the vascular wall of the hypoperfusion-induced AAA rat model. On the other hand, serum triglyceride levels and serum total cholesterol levels were not correlated with the number of adipocytes in the vascular wall. These results suggest that local adipocyte accumulation in the vascular wall, not serum lipids, has an important role in AAA rupture.

  14. Role of MicroRNA-103a Targeting ADAM10 in Abdominal Aortic Aneurysm

    PubMed Central

    Jiao, Tong; Yao, Ye; Zhang, Bo; Sun, Qing-Feng; Li, Jing-Bo; Yuan, Chao; Jing, Bao; Wang, Yun-Peng

    2017-01-01

    MicroRNAs (miRNAs) are deregulated in various vascular ailments including abdominal aortic aneurysm (AAA). MiR-103 is involved in vascular, metabolic, and malignant diseases, but whether it participates in the pathogenesis of AAA remains elusive. ADAM10 plays a vital role in the formation of aneurysm, but whether miRs modulate its activity during AAA formation is totally unknown. In this study, we detected the significantly increased protein expression of ADAM10 in angiotensin II induced murine AAA specimens, while the mRNA expression of ADAM10 was similar between AAA and control, suggesting the posttranscriptional regulation. The ADAM10 specific inhibitor GI254023X dramatically reduced the macrophage infiltration of murine abdominal aorta. Bioinformatic predictions suggest that ADAM10 is the target of miR-103a/107 but the binding site is exclusive. At the cellular level, miR-103a-1 suppressed the protein expression of ADAM10, while antisense miR-103a-1 increased its expression. Particularly, with the progression of murine AAA, the mRNA expression of miR-103a/107 substantially decreased and the protein expression of ADAM10 greatly increased. Together, our data afford the new insight that miR-103a inhibited AAA growth via targeting ADAM10, which might be a promising therapeutic strategy to alleviate AAA. PMID:28357407

  15. Update on Abdominal Aortic Aneurysm Research: From Clinical to Genetic Studies

    PubMed Central

    Kuivaniemi, Helena; Ryer, Evan J.; Elmore, James R.; Hinterseher, Irene; Smelser, Diane T.; Tromp, Gerard

    2014-01-01

    An abdominal aortic aneurysm (AAA) is a dilatation of the abdominal aorta with a diameter of at least 3.0 cm. AAAs are often asymptomatic and are discovered as incidental findings in imaging studies or when the AAA ruptures leading to a medical emergency. AAAs are more common in males than females, in individuals of European ancestry, and in those over 65 years of age. Smoking is the most important environmental risk factor. In addition, a positive family history of AAA increases the person's risk for AAA. Interestingly, diabetes has been shown to be a protective factor for AAA in many large studies. Hallmarks of AAA pathogenesis include inflammation, vascular smooth muscle cell apoptosis, extracellular matrix degradation, and oxidative stress. Autoimmunity may also play a role in AAA development and progression. In this Outlook paper, we summarize our recent studies on AAA including clinical studies related to surgical repair of AAA and genetic risk factor and large-scale gene expression studies. We conclude with a discussion on our research projects using large data sets available through electronic medical records and biobanks. PMID:24834361

  16. Role of MicroRNA-103a Targeting ADAM10 in Abdominal Aortic Aneurysm.

    PubMed

    Jiao, Tong; Yao, Ye; Zhang, Bo; Hao, Da-Cheng; Sun, Qing-Feng; Li, Jing-Bo; Yuan, Chao; Jing, Bao; Wang, Yun-Peng; Wang, Hai-Yang

    2017-01-01

    MicroRNAs (miRNAs) are deregulated in various vascular ailments including abdominal aortic aneurysm (AAA). MiR-103 is involved in vascular, metabolic, and malignant diseases, but whether it participates in the pathogenesis of AAA remains elusive. ADAM10 plays a vital role in the formation of aneurysm, but whether miRs modulate its activity during AAA formation is totally unknown. In this study, we detected the significantly increased protein expression of ADAM10 in angiotensin II induced murine AAA specimens, while the mRNA expression of ADAM10 was similar between AAA and control, suggesting the posttranscriptional regulation. The ADAM10 specific inhibitor GI254023X dramatically reduced the macrophage infiltration of murine abdominal aorta. Bioinformatic predictions suggest that ADAM10 is the target of miR-103a/107 but the binding site is exclusive. At the cellular level, miR-103a-1 suppressed the protein expression of ADAM10, while antisense miR-103a-1 increased its expression. Particularly, with the progression of murine AAA, the mRNA expression of miR-103a/107 substantially decreased and the protein expression of ADAM10 greatly increased. Together, our data afford the new insight that miR-103a inhibited AAA growth via targeting ADAM10, which might be a promising therapeutic strategy to alleviate AAA.

  17. Invariant-based anisotropic constitutive models of the healthy and aneurysmal abdominal aortic wall.

    PubMed

    Basciano, C A; Kleinstreuer, C

    2009-02-01

    The arterial wall is a complex fiber-reinforced composite. Pathological conditions, such as aneurysms, significantly alter the mechanical response of the arterial wall, resulting in a loss of elasticity, enhanced anisotropy, and increased chances of mechanical failure. Invariant-based models of the healthy and aneurysmal abdominal aorta were constructed based on first principles and published experimental data with implementations for several numerical cases, as well as comparisons to current healthy and aneurysmal tissue data. Inherent limitations of a traditional invariant-based methodology are also discussed and compared to the models' ability to accurately reproduce experimental trends. The models capture the nonlinear and anisotropic mechanical responses of the two arterial sections and make reasonable predictions regarding the effects of alterations in healthy and diseased tissue histology. Additionally, the new models exhibit convex and anisotropic monotonically increasing energy contours (suggesting numerical stability) but have potentially the inherent limitations of a covariant theoretical framework. Although the traditional invariant framework exhibits significant covariance, the invariant terms utilized in the new models exhibited limited covariance and are able to accurately reproduce experimental trends. A streamlined implementation is also possible for future numerical investigations of fluid-structure interactions in abdominal aortic aneurysms.

  18. The potential role of DNA methylation in the pathogenesis of abdominal aortic aneurysm.

    PubMed

    Toghill, Bradley J; Saratzis, Athanasios; Harrison, Seamus C; Verissimo, Ana R; Mallon, Eamonn B; Bown, Matthew J

    2015-07-01

    Abdominal aortic aneurysm (AAA) is characterised by the chronic degradation and gradual, irreversible dilation of the abdominal aorta. Smoking, genetics, male sex and increased age are major factors associated with developing AAA. Rupture contributes to around 2% of deaths in all Caucasians over 65, and there is no pharmaco-therapeutic treatment. Methylation is an epigenetic modification to DNA, where a methyl group is added to a cytosine base 5' to a guanine (CpG dinucleotide). Methylation patterns are long term, inherited signatures that can induce changes in gene transcription, and can be affected by both genetic and environmental factors. Methylation changes are involved in hypertension and atherosclerosis, both of which are risk factors of, and often coexist with AAA. Extra-cellular matrix degradation and inflammation, both important pathological hallmarks of AAA, are also promoted by changes in CpG methylation in other diseases. Additionally, the adverse effects of smoking and ageing take place largely through epigenetic manipulation of the genome. Every factor associated with AAA appears to be associated with DNA methylation, yet no direct evidence confirms this. Future work to identify a link between global methylation and AAA, and differentially methylated regions may reveal valuable insight. The identification of a common epigenetic switching process may also signify a promising future for AAA pharmaco-therapeutic strategies. Epigenetic therapies are being designed to target pathogenic CpG methylation changes in other diseases, and it is feasible that these therapies may also be applicable to AAA in the future.

  19. Fluid Characteristics in Abdominal Aortic Aneurysms (AAAs) and Its Correlation to Thrombus Formation

    NASA Astrophysics Data System (ADS)

    Tang, Rubing; Bar-Yoseph, Pinhas Z.; Lasheras, Juan

    2008-11-01

    It has been observed that most large Abdominal Aortic Aneurysms (AAAs) develop an intraluminal thrombus as they progressively enlarge. Previous studies have suggested that the build up of the thrombus may be associated with the altered hemodynamic patterns that arise inside the AAA. We have performed a parametrical computational study of the flow patterns inside enlarging AAA to investigate the possible mechanism controlling the thrombus formation. Pulsatile blood flows were simulated in idealized models of fusiform aneurysms with different dilatation ratios and the effects of shear-activated platelet accumulation and platelet/wall interaction were evaluated based on the calculated flow fields. The platelet activation level (PAL) was determined by computing the integral over time of flow shear stresses exerted over the platelets as they are transported throughout the aneurysm. Our results have shown that the values of PAL in AAAs are in fact smaller than the maximum value obtained in a healthy abdominal aorta. However, we show that the transportation of blood cells towards the wall and the formation of stagnation points on the aneurysm's wall play more significant roles in thrombus formation than PAL.

  20. Evolution of the wall shear stresses during the progressive enlargement of symmetric abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Salsac, A.-V.; Sparks, S. R.; Chomaz, J.-M.; Lasheras, J. C.

    2006-08-01

    The changes in the evolution of the spatial and temporal distribution of the wall shear stresses (WSS) and gradients of wall shear stresses (GWSS) at different stages of the enlargement of an abdominal aortic aneurysm (AAA) are important in understanding the aetiology and progression of this vascular disease since they affect the wall structural integrity, primarily via the changes induced on the shape, functions and metabolism of the endothelial cells. Particle image velocimetry (PIV) measurements were performed in in vitro aneurysm models, while changing their geometric parameters systematically. It has been shown that, even at the very early stages of the disease, i.e. increase in the diameter ≤ 50%, the flow separates from the wall and a large vortex ring, usually followed by internal shear layers, is created. These lead to the generation of WSS that drastically differ in mean and fluctuating components from the healthy vessel. Inside the AAA, the mean WSS becomes negative along most of the aneurysmal wall and the magnitude of the WSS can be as low as 26% of the value in a healthy abdominal aorta.

  1. Flow topology in patient-specific abdominal aortic aneurysms during rest and exercise

    NASA Astrophysics Data System (ADS)

    Arzani, Amirhossein; Shadden, Shawn

    2012-11-01

    Abdominal aortic aneurysm (AAA) is a permanent, localized widening of the abdominal aorta. Flow in AAA is dominated by recirculation, transitional turbulence and low wall shear stress. Image-based CFD has recently enabled high resolution flow data in patient-specific AAA. This study aims to characterize transport in different AAAs, and understand flow topology changes from rest to exercise, which has been a hypothesized therapy due to potential acute changes in flow. Velocity data in 6 patients with different AAA morphology were obtained using image-based CFD under rest and exercise conditions. Finite-time Lyapunov exponent (FTLE) fields were computed from integration of the velocity data to identify dominant Lagrangian coherent structures. The flow topology was compared between rest and exercise conditions. For all patients, the systolic inflow jet resulted in coherent vortex formation. The evolution of this vortex varied greatly between patients and was a major determinant of transport inside the AAA during diastole. During exercise, previously observed stagnant regions were either replaced with undisturbed flow, regions of uniform high mixing, or persisted relatively unchanged. A mix norm measure provided a quantitative assessment of mixing. This work was supported by the National Institutes of Health, grant number 5R21HL108272.

  2. A multimodality vascular imaging phantom of an abdominal aortic aneurysm with a visible thrombus

    SciTech Connect

    Allard, Louise; Chayer, Boris; Qin Zhao; Soulez, Gilles; Roy, David; Cloutier, Guy

    2013-06-15

    Purpose: With the continuous development of new stent grafts and implantation techniques, it has now become technically feasible to treat abdominal aortic aneurysms (AAA) with challenging anatomy using endovascular repair with standard, fenestrated, or branched stent-grafts. In vitro experimentations are very useful to improve stent-graft design and conformability or imaging guidance for stent-graft delivery or follow-up. Vascular replicas also help to better understand the limitation of endovascular approaches in challenging anatomy and possibly improve surgical planning or training by practicing high risk clinical procedures in the laboratory to improve outcomes in the operating room. Most AAA phantoms available have a very basic anatomy, which is not representative of the clinical reality. This paper presents a method of fabrication of a realistic AAA phantom with a visible thrombus, as well as some mechanical properties characterizing such phantom. Methods: A realistic AAA geometry replica of a real patient anatomy taken from a multidetector computed tomography (CT) scan was manufactured. To demonstrate the multimodality imaging capability of this new phantom with a thrombus visible in magnetic resonance (MR) angiography, CT angiography (CTA), digital subtraction angiography (DSA), and ultrasound, image acquisitions with all these modalities were performed by using standard clinical protocols. Potential use of this phantom for stent deployment was also tested. A rheometer allowed defining hyperelastic and viscoelastic properties of phantom materials. Results: MR imaging measurements of SNR and CNR values on T1 and T2-weighted sequences and MR angiography indicated reasonable agreement with published values of AAA thrombus and abdominal components in vivo. X-ray absorption also lay within normal ranges of AAA patients and was representative of findings observed on CTA, fluoroscopy, and DSA. Ultrasound propagation speeds for developed materials were also in

  3. Total laparorobotic repair of abdominal aortic aneurysm with sac exclusion obliteration and aortobifemoral bypass.

    PubMed

    Wu, Timothy; Prema, Jateen; Zagaja, Gregory; Shalhav, Arieh; Bassiouny, Hisham S

    2009-01-01

    A 65-year-old man with coronary artery disease, hypertension, and peripheral vascular disease was found to have an asymptomatic abdominal aortic aneurysm (AAA) of 5.5 cm on surveillance for his peripheral vascular disease. Cardiac stress testing demonstrated no evidence of myocardial ischemia, and he opted to undergo open repair of his aneurysm. Laparorobotic repair of the infrarenal AAA using the da Vinci robotic system was performed with an aortobifemoral bypass. We describe a novel technique for AAA exclusion using a cerclage method, which greatly facilitates repair of infrarenal AAAs using laparorobotic techniques. Laparorobotic repair of infrarenal AAA can be greatly facilitated by AAA sac exclusion and obliteration without the need to ligate all lumbar arteries or to open the aneurysm. This virtually avoids blood loss from the sac and minimizes the possibility for open conversion as a result of poor visualization. Minimally invasive aortic intervention for aneurysmal disease using laparascopic methods has been reported in the literature. Problems associated with this technique include a prolonged learning curve and difficulty completing intracorporeal anastomoses. Robotic surgery provides an advantage over laparoscopic surgery in its ability to provide greater degrees of freedom in a relatively small field of view along with superior high-definition, three-dimensional visualization. To date, there have been no known reports of using robotic surgery in the United States as a sole method for repair of AAA. We report our technique of combining robotic surgery with a novel procedure for sac exclusion and obliteration to successfully repair AAA without the need for opening the aneurysm sac and endoaneurysmorrhaphy.

  4. Adventitial Tertiary Lymphoid Organs as Potential Source of MicroRNA Biomarkers for Abdominal Aortic Aneurysm.

    PubMed

    Spear, Rafaelle; Boytard, Ludovic; Blervaque, Renaud; Chwastyniak, Maggy; Hot, David; Vanhoutte, Jonathan; Staels, Bart; Lemoine, Yves; Lamblin, Nicolas; Pruvot, François-René; Haulon, Stephan; Amouyel, Philippe; Pinet, Florence

    2015-05-18

    Abdominal aortic aneurysm (AAA) is an inflammatory disease associated with marked changes in the cellular composition of the aortic wall. This study aims to identify microRNA (miRNA) expression in aneurysmal inflammatory cells isolated by laser microdissection from human tissue samples. The distribution of inflammatory cells (neutrophils, B and T lymphocytes, mast cells) was evaluated in human AAA biopsies. We observed in half of the samples that adventitial tertiary lymphoid organs (ATLOs) with a thickness from 0.5 to 2 mm were located exclusively in the adventitia. Out of the 850 miRNA that were screened by microarray in isolated ATLOs (n = 2), 164 miRNAs were detected in ATLOs. The three miRNAs (miR-15a-3p, miR-30a-5p and miR-489-3p) with the highest expression levels were chosen and their expression quantified by RT-PCR in isolated ATLOs (n = 4), M1 (n = 2) and M2 macrophages (n = 2) and entire aneurysmal biopsies (n = 3). Except for the miR-30a-5p, a similar modulation was found in ATLOs and the two subtypes of macrophages. The modulated miRNAs were then evaluated in the plasma of AAA patients for their potential as AAA biomarkers. Our data emphasize the potential of miR-15a-3p and miR-30a-5p as biomarkers of AAA but also as triggers of ATLO evolution. Further investigations will be required to evaluate their targets in order to better understand AAA pathophysiology.

  5. EPA Prevents the Development of Abdominal Aortic Aneurysms through Gpr-120/Ffar-4.

    PubMed

    Kamata, Ryo; Bumdelger, Batmunkh; Kokubo, Hiroki; Fujii, Masayuki; Yoshimura, Koichi; Ishida, Takafumi; Ishida, Mari; Yoshizumi, Masao

    2016-01-01

    Abdominal aortic aneurysms (AAAs), which commonly occur among elderly individuals, are accompanied by a risk of rupture with a high mortality rate. Although eicosapentaenoic acid (EPA) has been reported to prevent AAA formation, the mechanism by which EPA works on vascular smooth muscle cells is unknown. This study aimed to investigate the mechanism by which orally-administered EPA prevents the formation of severe AAAs that develop in Osteoprotegerin (Opg) knockout (KO) mice. In the CaCl2-induced AAA model, EPA attenuated the enhanced progression of AAAs in Opg-KO mice, including the increase in aortic diameter with destruction of elastic fibers in the media. Immunohistochemical analyses showed that EPA reduced the phosphorylation of transforming growth factor beta-activated kinase-1/Map3k7 (Tak-1) and c-Jun NH2-terminal kinase (JNK), as well as the expression of Matrix metalloproteinase-9 (Mmp-9) in the media of the aorta. In smooth muscle cell cultures, rh-TRAIL-induced activation of the Tak-1-JNK pathway and increase in Mmp-9 expression were inhibited by EPA. Moreover, GW9508, a specific ligand for G-protein coupled receptor (Gpr)-120/Free fatty acid receptor (Ffar)-4, mimicked the effects of EPA. The effects of EPA were abrogated by knockdown of the Gpr-120/Ffar-4 receptor gene. Our data demonstrate that the Trail-Tak-1-JNK-Mmp-9 pathway is responsible for the enhancement of AAAs in Opg-KO mice, and that EPA inhibits the Tak-1-JNK pathway by activating Gpr-120/Ffar-4, which results in the attenuation of AAA development.

  6. Isotropic 3D Black Blood MRI of Abdominal Aortic Aneurysm Wall and Intraluminal Thrombus

    PubMed Central

    Zhu, Chengcheng; Haraldsson, Henrik; Faraji, Farshid; Owens, Christopher; Gasper, Warren; Ahn, Sinyeob; Liu, Jing; Laub, Gerhard; Hope, Michael D.; Saloner, David

    2015-01-01

    Introduction The aortic wall and intraluminal thrombus (ILT) have been increasingly studied as potential markers of progressive disease with abdominal aortic aneurysms (AAAs). Our goal was to develop a high resolution, 3D black blood MR technique for AAA wall and ILT imaging within a clinically acceptable scan time. Methods Twenty two patients with AAAs (maximal diameter 4.3±1.0cm), along with five healthy volunteers, were imaged at 3T with a 3D T1-weighted fast-spin-echo sequence using variable flip angle trains (SPACE) with a preparation pulse (DANTE) for suppressing blood signal. Volunteers and ten patients were also scanned with SPACE alone for comparison purposes. The signal to noise ratio (SNR) and the aortic wall/ILT to lumen contrast to noise ratio (CNR) were measured. Qualitative image scores (1–4 scale) assessing the inner lumen and outer wall boundaries of AAA were performed by two blinded reviewers. In patients with ILT, the ratio of ILT signal intensity (ILTSI) over psoas muscle SI (MuscleSI) was calculated, and the signal heterogeneity of ILT was quantified as standard deviation (SD) over the mean. Results All subjects were imaged successfully with an average scan time of 7.8±0.7 minutes. The DANTE preparation pulse for blood suppression substantially reduced flow artifacts in SPACE with lower lumen SNR (8.8 vs. 21.4, p<0.001) and improved the wall/ILT to lumen CNR (9.9 vs. 6.3, p<0.001) in patients. Qualitative assessment showed improved visualization of lumen boundaries (73% higher scores on average, p=0.01) and comparable visualization of outer wall boundary (p>0.05). ILT was present in ten patients, with relatively high signal and a wide SD (average ILTSI/MuscleSI 1.42±0.48 (range 0.75–2.11) ) and with SD/mean of 27.7%±6.6% (range 19.6% – 39.4%). Conclusion High resolution, 3D black blood MRI of AAAs can be achieved in a clinical accepted scan time with reduction of flow artifacts using the DANTE preparation pulse. Signal characteristics

  7. A New Animal Model for Investigation of Mechanical Unloading in Hypertrophic and Failing Hearts: Combination of Transverse Aortic Constriction and Heterotopic Heart Transplantation

    PubMed Central

    Stenzig, Justus; Biermann, Daniel; Jelinek, Marisa; Reichenspurner, Hermann; Eschenhagen, Thomas; Ehmke, Heimo; Schwoerer, Alexander P.

    2016-01-01

    Objectives Previous small animal models for simulation of mechanical unloading are solely performed in healthy or infarcted hearts, not representing the pathophysiology of hypertrophic and dilated hearts emerging in heart failure patients. In this article, we present a new and economic small animal model to investigate mechanical unloading in hypertrophic and failing hearts: the combination of transverse aortic constriction (TAC) and heterotopic heart transplantation (hHTx) in rats. Methods To induce cardiac hypertrophy and failure in rat hearts, three-week old rats underwent TAC procedure. Three and six weeks after TAC, hHTx with hypertrophic and failing hearts in Lewis rats was performed to induce mechanical unloading. After 14 days of mechanical unloading animals were euthanatized and grafts were explanted for further investigations. Results 50 TAC procedures were performed with a survival of 92% (46/50). When compared to healthy rats left ventricular surface decreased to 5.8±1.0 mm² (vs. 9.6± 2.4 mm²) (p = 0.001) after three weeks with a fractional shortening (FS) of 23.7± 4.3% vs. 28.2± 1.5% (p = 0.01). Six weeks later, systolic function decreased to 17.1± 3.2% vs. 28.2± 1.5% (p = 0.0001) and left ventricular inner surface increased to 19.9±1.1 mm² (p = 0.0001). Intraoperative graft survival during hHTx was 80% with 46 performed procedures (37/46). All transplanted organs survived two weeks of mechanical unloading. Discussion Combination of TAC and hHTx in rats offers an economic and reproducible small animal model enabling serial examination of mechanical unloading in a truly hypertrophic and failing heart, representing the typical pressure overloaded and dilated LV, occurring in patients with moderate to severe heart failure. PMID:26841021

  8. Role of serotonin 5-HT2A receptors in the development of cardiac hypertrophy in response to aortic constriction in mice.

    PubMed

    Lairez, O; Cognet, T; Schaak, S; Calise, D; Guilbeau-Frugier, C; Parini, A; Mialet-Perez, J

    2013-06-01

    Serotonin, in addition to its fundamental role as a neurotransmitter, plays a critical role in the cardiovascular system, where it is thought to be involved in the development of cardiac hypertrophy and failure. Indeed, we recently found that mice with deletion of monoamine oxidase A had enhanced levels of blood and cardiac 5-HT, which contributed to exacerbation of hypertrophy in a model of experimental pressure overload. 5-HT2A receptors are expressed in the heart and mediate a hypertrophic response to 5-HT in cardiac cells. However, their role in cardiac remodeling in vivo and the signaling pathways associated are not well understood. In the present study, we evaluated the effect of a selective 5-HT2A receptor antagonist, M100907, on the development of cardiac hypertrophy induced by transverse aortic constriction (TAC). Cardiac 5-HT2A receptor expression was transiently increased after TAC, and was recapitulated in cardiomyocytes, as observed with 5-HT2A in situ labeling by immunohistochemistry. Selective blockade of 5-HT2A receptors prevented the development of cardiac hypertrophy, as measured by echocardiography, cardiomyocyte area and heart weight-to-body weight ratio. Interestingly, activation of calmodulin kinase (CamKII), which is a core mechanism in cardiac hypertrophy, was reduced in cardiac samples from M100907-treated TAC mice compared to vehicle-treated mice. In addition, phosphorylation of histone deacetylase 4 (HDAC4), a downstream partner of CamKII was significantly diminished in M100907-treated TAC mice. Thus, our results show that selective blockade of 5-HT2A receptors has beneficial effect in the development of cardiac hypertrophy through inhibition of the CamKII/HDAC4 pathway.

  9. Non-Invasive Pulse Wave Analysis in a Thrombus-Free Abdominal Aortic Aneurysm after Implantation of a Nitinol Aortic Endograft

    PubMed Central

    Georgakarakos, Efstratios; Argyriou, Christos; Georgiadis, George S.; Lazarides, Miltos K.

    2016-01-01

    Endovascular aneurysm repair has been associated with changes in arterial stiffness, as estimated by pulse wave velocity (PWV). This marker is influenced by the medical status of the patient, the elastic characteristics of the aneurysm wall, and the presence of intraluminal thrombus. Therefore, in order to delineate the influence of the endograft implantation in the early post-operative period, we conducted non-invasively pulse wave analysis in a male patient with an abdominal aortic aneurysm containing no intraluminal thrombus, unremarkable past medical history, and absence of peripheral arterial disease. The estimated parameters were the systolic and diastolic pressure calculated at the aortic level (central pressures), PWV, augmentation pressure (AP) and augmentation index (AI), pressure wave reflection magnitude (RM), and peripheral resistance. Central systolic and diastolic pressure decreased post-operatively. PWV showed subtle changes from 11.6 to 10.6 and 10.9 m/s at 1-week and 1-month, respectively. Accordingly, the AI decreased from 28 to 14% and continued to drop to 25%. The AP decreased gradually from 15 to 6 and 4 mmHg. The wave RM dropped from 68 to 52% at 1-month. Finally, the peripheral resistance dropped from 1.41 to 0.99 and 0.85 dyn × s × cm−5. Our example shows that the implantation of an aortic endograft can modify the pressure wave reflection over the aortic bifurcation without causing significant alterations in PWV. PMID:26793712

  10. CFD and PTV steady flow investigation in an anatomically accurate abdominal aortic aneurysm.

    PubMed

    Boutsianis, Evangelos; Guala, Michele; Olgac, Ufuk; Wildermuth, Simon; Hoyer, Klaus; Ventikos, Yiannis; Poulikakos, Dimos

    2009-01-01

    There is considerable interest in computational and experimental flow investigations within abdominal aortic aneurysms (AAAs). This task stipulates advanced grid generation techniques and cross-validation because of the anatomical complexity. The purpose of this study is to examine the feasibility of velocity measurements by particle tracking velocimetry (PTV) in realistic AAA models. Computed tomography and rapid prototyping were combined to digitize and construct a silicone replica of a patient-specific AAA. Three-dimensional velocity measurements were acquired using PTV under steady averaged resting boundary conditions. Computational fluid dynamics (CFD) simulations were subsequently carried out with identical boundary conditions. The computational grid was created by splitting the luminal volume into manifold and nonmanifold subsections. They were filled with tetrahedral and hexahedral elements, respectively. Grid independency was tested on three successively refined meshes. Velocity differences of about 1% in all three directions existed mainly within the AAA sack. Pressure revealed similar variations, with the sparser mesh predicting larger values. PTV velocity measurements were taken along the abdominal aorta and showed good agreement with the numerical data. The results within the aneurysm neck and sack showed average velocity variations of about 5% of the mean inlet velocity. The corresponding average differences increased for all velocity components downstream the iliac bifurcation to as much as 15%. The two domains differed slightly due to flow-induced forces acting on the silicone model. Velocity quantification through narrow branches was problematic due to decreased signal to noise ratio at the larger local velocities. Computational wall pressure and shear fields are also presented. The agreement between CFD simulations and the PTV experimental data was confirmed by three-dimensional velocity comparisons at several locations within the investigated AAA

  11. Histology and Biaxial Mechanical Behavior of Abdominal Aortic Aneurysm Tissue Samples.

    PubMed

    Pancheri, Francesco Q; Peattie, Robert A; Reddy, Nithin D; Ahamed, Touhid; Lin, Wenjian; Ouellette, Timothy D; Iafrati, Mark D; Luis Dorfmann, A

    2017-03-01

    Abdominal aortic aneurysms (AAAs) represent permanent, localized dilations of the abdominal aorta that can be life-threatening if progressing to rupture. Evaluation of risk of rupture depends on understanding the mechanical behavior of patient AAA walls. In this project, a series of patient AAA wall tissue samples have been evaluated through a combined anamnestic, mechanical, and histopathologic approach. Mechanical properties of the samples have been characterized using a novel, strain-controlled, planar biaxial testing protocol emulating the in vivo deformation of the aorta. Histologically, the tissue ultrastructure was highly disrupted. All samples showed pronounced mechanical stiffening with stretch and were notably anisotropic, with greater stiffness in the circumferential than the axial direction. However, there were significant intrapatient variations in wall stiffness and stress. In biaxial tests in which the longitudinal stretch was held constant at 1.1 as the circumferential stretch was extended to 1.1, the maximum average circumferential stress was 330 ± 70 kPa, while the maximum average axial stress was 190 ± 30 kPa. A constitutive model considering the wall as anisotropic with two preferred directions fit the measured data well. No statistically significant differences in tissue mechanical properties were found based on patient gender, age, maximum bulge diameter, height, weight, body mass index, or smoking history. Although a larger patient cohort is merited to confirm these conclusions, the project provides new insight into the relationships between patient natural history, histopathology, and mechanical behavior that may be useful in the development of accurate methods for rupture risk evaluation.

  12. Evaluation of texture for classification of abdominal aortic aneurysm after endovascular repair.

    PubMed

    García, Guillermo; Maiora, Josu; Tapia, Arantxa; De Blas, Mariano

    2012-06-01

    The use of the endovascular prostheses in abdominal aortic aneurysm has proven to be an effective technique to reduce the pressure and rupture risk of aneurysm. Nevertheless, in a long-term perspective, complications such as leaks inside the aneurysm sac (endoleaks) could appear causing a pressure elevation and increasing the danger of rupture consequently. At present, computed tomographic angiography (CTA) is the most common examination for medical surveillance. However, endoleak complications cannot always be detected by visual inspection on CTA scans. The investigation on new techniques to detect endoleaks and analyse their effects on treatment evolution is of great importance for endovascular aneurysm repair (EVAR) technique. The purpose of this work was to evaluate the capability of texture features obtained from the aneurysmatic thrombus CT images to discriminate different types of evolutions caused by endoleaks. The regions of interest (ROIs) from patients with different post-EVAR evolution were extracted by experienced radiologists. Three techniques were applied to each ROI to obtain texture parameters, namely the grey level co-occurrence matrix (GLCM), the grey level run length matrix (GLRLM) and the grey level difference method (GLDM). The results showed that GLCM, GLRLM and GLDM features presented a good discrimination ability to differentiate between favourable or unfavourable evolutions. GLCM was the most efficient in terms of classification accuracy (93.41% ± 0.024) followed by GLRLM (90.17% ± 0.077) and finally by GLDM (81.98% ± 0.045). According to the results, we can consider texture analysis as complementary information to classified abdominal aneurysm evolution after EVAR.

  13. Robust and fast abdominal aortic aneurysm centerline detection for rupture risk prediction

    NASA Astrophysics Data System (ADS)

    Zhang, Hong; Finol, Ender A.

    2011-03-01

    This work describes a robust and fast semi-automatic approach for Abdominal Aortic Aneurysm (AAA) centerline detection. AAA is a vascular disease accompanied by progressive enlargement of the abdominal aorta, which leads to rupture if left untreated, an event that accounts for the 13th leading cause of death in the U.S. The lumen centerline can be used to provide the initial starting points for thrombus segmentation. Different from other methods, which are mostly based on region growing and suffer from problems of leakage and heavy computational burden, we propose a novel method based on online classification. An online version of the adaboost classifier based on steerable features is applied to AAA MRI data sets with a rectangular box enclosing the lumen in the first slice. The classifier is updated during the tracking process by using the testing result of the previous image as the new training data. Unlike traditional offline versions, the online classifier can adjust parameters automatically when a leakage occurs. With the help of integral images on the computation of haar-like features, the method can achieve nearly real time processing (about 2 seconds per image on a standard workstation). Ten ruptured and ten unruptured AAA data sets were processed and the tortuosity of the 20 centerlines was calculated. The correlation coefficient of the tortuosity was calculated to illustrate the significance of the prediction with the proposed method. The mean relative accuracy is 95.68% with a standard deviation of 0.89% when compared to a manual segmentation procedure. The correlation coefficient is 0.394.

  14. Human Adipose-Derived Stem Cells Suppress Elastase-Induced Murine Abdominal Aortic Inflammation and Aneurysm Expansion Through Paracrine Factors.

    PubMed

    Xie, Jie; Jones, Thomas J; Feng, Dongni; Cook, Todd G; Jester, Andrea A; Yi, Ru; Jawed, Yameena T; Babbey, Clifford; March, Keith L; Murphy, Michael P

    2017-02-16

    Abdominal aortic aneurysm (AAA) is a potentially lethal disease associated with immune activation-induced aortic degradation. We hypothesized that xenotransplantation of human adipose-derived stem cells (hADSCs) would reduce aortic inflammation and attenuate expansion in a murine AAA model. Modulatory effects of ADSCs on immune cell subtypes associated with AAA progression were investigated using human peripheral blood mononuclear cells (hPBMNCs) cocultured with ADSCs. Murine AAA was induced through elastase application to the abdominal aorta in C57BL/6 mice. ADSCs were administered intravenously, and aortic changes were determined by ultrasonography and videomicrometry. Circulating monocytes, aortic neutrophils, CD28- T cells, FoxP3+ regulatory T cells (Tregs), and CD206+ M2 macrophages were assessed at multiple terminal time points. In vitro, ADSCs induced M2 macrophage and Treg phenotypes while inhibiting neutrophil transmigration and lymphocyte activation without cellular contact. Intravenous ADSC delivery reduced aneurysmal expansion starting from day 4 [from baseline: 54.8% (saline) vs. 16.9% (ADSCs), n = 10 at baseline, n = 4 at day 4, p < 0.001], and the therapeutic effect persists through day 14 (from baseline: 64.1% saline vs. 24.6% ADSCs, n = 4, p < 0.01). ADSC administration increased aortic Tregs by 20-fold (n = 5, p < 0.01), while decreasing CD4+CD28- (-28%), CD8+CD28- T cells (-61%), and Ly6G/C+ neutrophils (-43%, n = 5, p < 0.05). Circulating CD115+CXCR1-LY6C+-activated monocytes decreased in the ADSC-treated group by day 7 (-60%, n = 10, p < 0.05), paralleled by an increase in aortic CD206+ M2 macrophages by 2.4-fold (n = 5, p < 0.05). Intravenously injected ADSCs transiently engrafted in the lung on day 1 without aortic engraftment at any time point. In conclusion, ADSCs exhibit pleiotropic immunomodulatory effects in vitro as well as in vivo during the development of AAA. The temporal evolution

  15. Fruit Intake and Abdominal Aortic Calcification in Elderly Women: A Prospective Cohort Study.

    PubMed

    Bondonno, Nicola P; Lewis, Joshua R; Prince, Richard L; Lim, Wai H; Wong, Germaine; Schousboe, John T; Woodman, Richard J; Kiel, Douglas P; Bondonno, Catherine P; Ward, Natalie C; Croft, Kevin D; Hodgson, Jonathan M

    2016-03-10

    Cardiovascular disease (CVD) is the leading cause of death worldwide. There is a consistent inverse relationship between fruit intake with CVD events and mortality in cross-sectional and prospective observational studies, but the relationship of fruit intake with measurements of atherosclerosis in humans is less clear. Nutritional effects on abdominal aortic calcification (AAC), a marker for subclinical intimal and medial atherosclerotic vascular disease, have not been studied previously. The aim of this study was to examine the cross-sectional relationship of total and individual fruit (apple, pear, orange and other citrus, and banana) intake with AAC, scored between 0 and 24. The current study assessed baseline data for a cohort of 1052 women over 70 years of age who completed both a food frequency questionnaire assessing fruit intake, and underwent AAC measurement using dual energy X-ray absorptiometry. AAC scores were significantly negatively correlated with total fruit and apple intakes (p < 0.05), but not with pear, orange or banana intakes (p > 0.25). In multivariable-adjusted logistic regression, each standard deviation (SD; 50 g/day) increase in apple intake was associated with a 24% lower odds of having severe AAC (AAC score >5) (odd ratio OR): 0.76 (0.62, 0.93), p = 0.009). Total and other individual fruit intake were not associated with increased odds of having severe AAC. Apple but not total or other fruit intake is independently negatively associated with AAC in older women.

  16. Sac Angiography and Glue Embolization in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysm

    SciTech Connect

    Koike, Yuya Nishimura, Jun-ichi Hase, Soichiro Yamasaki, Motoshige

    2015-04-15

    PurposeThe purpose of this study was to demonstrate a sac angiography technique and evaluate the feasibility of N-butyl cyanoacrylate (NBCA) embolization of the ruptured abdominal aortic aneurysm (AAA) sac in emergency endovascular aneurysm repair (EVAR) in hemodynamically unstable patients.MethodsA retrospective case series of three patients in whom sac angiography was performed during emergency EVAR for ruptured AAA was reviewed. After stent graft deployment, angiography within the sac of aneurysm (sac angiography) was performed by manually injecting 10 ml of contrast material through a catheter to identify the presence and site of active bleeding. In two patients, sac angiography revealed active extravasation of the contrast material, and NBCA embolization with a coaxial catheter system was performed to achieve prompt sealing.ResultsSac angiography was successful in all three patients. In the two patients who underwent NBCA embolization for aneurysm sac bleeding, follow-up computed tomography (CT) images demonstrated the accumulation of NBCA consistent with the bleeding site in preprocedural CT images.ConclusionsEVAR is associated with a potential risk of ongoing bleeding from type II or IV endoleaks into the disrupted aneurysm sac in patients with severe coagulopathy. Therefore, sac angiography and NBCA embolization during emergency EVAR may represent a possible technical improvement in the treatment of ruptured AAA in hemodynamically unstable patients.

  17. Effect of exercise on patient specific abdominal aortic aneurysm flow topology and mixing.

    PubMed

    Arzani, Amirhossein; Les, Andrea S; Dalman, Ronald L; Shadden, Shawn C

    2014-02-01

    Computational fluid dynamics modeling was used to investigate changes in blood transport topology between rest and exercise conditions in five patient-specific abdominal aortic aneurysm models. MRI was used to provide the vascular anatomy and necessary boundary conditions for simulating blood velocity and pressure fields inside each model. Finite-time Lyapunov exponent fields and associated Lagrangian coherent structures were computed from blood velocity data and were used to compare features of the transport topology between rest and exercise both mechanistically and qualitatively. A mix-norm and mix-variance measure based on fresh blood distribution throughout the aneurysm over time were implemented to quantitatively compare mixing between rest and exercise. Exercise conditions resulted in higher and more uniform mixing and reduced the overall residence time in all aneurysms. Separated regions of recirculating flow were commonly observed in rest, and these regions were either reduced or removed by attached and unidirectional flow during exercise, or replaced with regional chaotic and transiently turbulent mixing, or persisted and even extended during exercise. The main factor that dictated the change in flow topology from rest to exercise was the behavior of the jet of blood penetrating into the aneurysm during systole.

  18. Flow of a blood analogue fluid in a compliant abdominal aortic aneurysm model: experimental modelling.

    PubMed

    Deplano, Valérie; Knapp, Yannick; Bailly, Lucie; Bertrand, Eric

    2014-04-11

    The aim of this work is to develop a unique in vitro set-up in order to analyse the influence of the shear thinning fluid-properties on the flow dynamics within the bulge of an abdominal aortic aneurysm (AAA). From an experimental point of view, the goals are to elaborate an analogue shear thinning fluid mimicking the macroscopic blood behaviour, to characterise its rheology at low shear rates and to propose an experimental device able to manage such an analogue fluid without altering its feature while reproducing physiological flow rate and pressure, through compliant AAA. Once these experimental prerequisites achieved, the results obtained in the present work show that the flow dynamics is highly dependent on the fluid rheology. The main results point out that the propagation of the vortex ring, generated in the AAA bulge, is slower for shear thinning fluids inducing a smaller travelled distance by the vortex ring so that it never impacts the anterior wall in the distal region, in opposition to Newtonian fluids. Moreover, scalar shear rate values are globally lower for shear thinning fluids inducing higher maximum stress values than those for the Newtonian fluids. Consequently, this work highlights that a Newtonian fluid model is finally inadequate to obtain a reliable prediction of the flow dynamics within AAA.

  19. Therapeutic potential of tetracycline derivatives to suppress the growth of abdominal aortic aneurysms.

    PubMed

    Thompson, R W; Liao, S; Curci, J A

    1998-11-01

    Abdominal aortic aneurysms (AAA) represent a potentially lethal disorder associated with aging and atherosclerosis. Although current management of AAA is predicted on early detection and elective surgical repair, routine screening for AAA is infrequent, because most AAA are too small to warrant repair when first detected and because there are no therapeutic approaches proven to suppress aneurysm expansion. Basic research on this problem suggests that chronic inflammation and increased local production of elastin-degrading proteinases play prominent roles in the process of aneurysmal degeneration. Members of the matrix metalloproteinases (MMP) family appear to be the most prominent elastases produced in human AAA, suggesting that unique therapeutic targets might exist for aneurysm disease. Studies using a representative animal model for AAA support this view, providing a means for further development of pharmacological approaches to suppress aneurysm expansion. Indeed, recent work indicates that tetracycline derivatives have the potential to interrupt the progressive connective tissue destruction that occurs in AAA, by virtue of their non-antimicrobial properties as MMP inhibitors, and they do so at clinically achievable dose schedules. These findings support the view that MMPs are potentially important pharmacotherapeutic targets in AAA and, moreover, that tetracyclines might be useful in suppressing aneurysm expansion in vivo. Because tetracycline derivatives offer a number of distinct advantages as MMP inhibitors for patients with small AAA, prospective clinical trials of this novel therapeutic strategy can be anticipated in the near future.

  20. Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index.

    PubMed

    Polzer, Stanislav; Gasser, T Christian

    2015-12-06

    A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach.

  1. Quantitative HDL Proteomics Identifies Peroxiredoxin-6 as a Biomarker of Human Abdominal Aortic Aneurysm

    PubMed Central

    Burillo, Elena; Jorge, Inmaculada; Martínez-López, Diego; Camafeita, Emilio; Blanco-Colio, Luis Miguel; Trevisan-Herraz, Marco; Ezkurdia, Iakes; Egido, Jesús; Michel, Jean-Baptiste; Meilhac, Olivier; Vázquez, Jesús; Martin-Ventura, Jose Luis

    2016-01-01

    High-density lipoproteins (HDLs) are complex protein and lipid assemblies whose composition is known to change in diverse pathological situations. Analysis of the HDL proteome can thus provide insight into the main mechanisms underlying abdominal aortic aneurysm (AAA) and potentially detect novel systemic biomarkers. We performed a multiplexed quantitative proteomics analysis of HDLs isolated from plasma of AAA patients (N = 14) and control study participants (N = 7). Validation was performed by western-blot (HDL), immunohistochemistry (tissue), and ELISA (plasma). HDL from AAA patients showed elevated expression of peroxiredoxin-6 (PRDX6), HLA class I histocompatibility antigen (HLA-I), retinol-binding protein 4, and paraoxonase/arylesterase 1 (PON1), whereas α-2 macroglobulin and C4b-binding protein were decreased. The main pathways associated with HDL alterations in AAA were oxidative stress and immune-inflammatory responses. In AAA tissue, PRDX6 colocalized with neutrophils, vascular smooth muscle cells, and lipid oxidation. Moreover, plasma PRDX6 was higher in AAA (N = 47) than in controls (N = 27), reflecting increased systemic oxidative stress. Finally, a positive correlation was recorded between PRDX6 and AAA diameter. The analysis of the HDL proteome demonstrates that redox imbalance is a major mechanism in AAA, identifying the antioxidant PRDX6 as a novel systemic biomarker of AAA. PMID:27934969

  2. Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index

    PubMed Central

    Polzer, Stanislav; Gasser, T. Christian

    2015-01-01

    A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach. PMID:26631334

  3. A simulation framework for estimating wall stress distribution of abdominal aortic aneurysm.

    PubMed

    Qin, Jing; Zhang, Jing; Chui, Chee-Kong; Huang, Wei-Min; Yang, Tao; Pang, Wai-Man; Sudhakar, Venkatesh; Chang, Stephen

    2011-01-01

    Abdominal aortic aneurysm (AAA) rupture is believed to occur when the mechanical stress acting on the wall exceeds the strength of the wall tissue. In endovascular aneurysm repair, a stent-graft in a catheter is released at the aneurysm site to form a new blood vessel and protect the weakened AAA wall from the pulsatile pressure and, hence, possible rupture. In this paper, we propose a framework to estimate the wall stress distribution of non-stented/stented AAA based on fluid-structure interaction, which is utilized in a surgical simulation system (IRAS). The 3D geometric model of AAA is reconstructed from computed tomography angiographic (CTA) images. Based on our experiments, a combined logarithm and polynomial strain energy equation is applied to model the elastic properties of arterial wall. The blood flow is modeled as laminar, incompressible, and non-Newtonian flow by applying Navier-Stokes equation. The obtained pressure of blood flow is applied as load on the AAA meshes with and without stent-graft and the wall stress distribution is calculated by fluid-structure interaction (FSI) solver equipped in ANSYS. Experiments demonstrate that our analytical results are consistent with clinical observations.

  4. Endovascular Aneurysm Sealing for the Treatment of Ruptured Abdominal Aortic Aneurysms

    PubMed Central

    Brownrigg, Jack R. W.; Karthikesalingam, Alan; Patterson, Benjamin O.; Holt, Peter J. E.; Hinchliffe, Robert J.; Morgan, Robert A.; Loftus, Ian M.; Thompson, Matthew M.

    2015-01-01

    Purpose: To assess the feasibility and report preliminary results of ruptured abdominal aortic aneurysm (rAAA) repair with endovascular aneurysm sealing (EVAS), a novel therapeutic alternative whose feasibility has not been established in rAAAs due to the unknown effects of the rupture site on the ability to achieve sealing. Case Report: Between December 2013 and April 2014, 5 patients (median age 71 years, range 57–90; 3 men) with rAAAs were treated with the Nellix EVAS system at a single institution. Median aneurysm diameter was 70 mm (range 67–91). Aneurysm morphology in 4 of the 5 patients was noncompliant with instructions for use (IFU) for both EVAS and standard stent-grafts; the remaining patient was outside the IFU for standard stent-grafts but treated with EVAS under standard IFU for the Nellix system. Median Hardman index was 2 (range 0–3). Two patients died of multiorgan failure after re-laparotomy and intraoperative cardiac arrest, respectively. Among survivors, all devices were patent with no signs of endoleak or failed aneurysm sac sealing at 6 months (median follow-up 9.2 months). Conclusion: EVAS for the management of infrarenal rAAAs appears feasible. The use of EVAS in emergency repairs may broaden the selection criteria of the current endovascular strategy to include patients with more complex aneurysm morphology. PMID:25904491

  5. Deformable Surface Model for the Evaluation of Abdominal Aortic Aneurysms Treated with an Endovascular Sealing System.

    PubMed

    Casciaro, Mariano E; El-Batti, Salma; Chironi, Gilles; Simon, Alain; Mousseaux, Elie; Armentano, Ricardo L; Alsac, Jean-Marc; Craiem, Damian

    2016-05-01

    Rupture of abdominal aortic aneurysms (AAA) is responsible for 1-3% of all deaths among the elderly population in developed countries. A novel endograft proposes an endovascular aneurysm sealing (EVAS) system that isolates the aneurysm wall from blood flow using a polymer-filled endobag that surrounds two balloon-expandable stents. The volume of injected polymer is determined by monitoring the endobag pressure but the final AAA expansion remains unknown. We conceived and developed a fully deformable surface model for the comparison of pre-operative sac lumen size and final endobag size (measured using a follow-up scan) with the volume of injected polymer. Computed tomography images were acquired for eight patients. Aneurysms were manually and automatically segmented twice by the same observer. The injected polymer volume resulted 9% higher than the aneurysm pre-operative lumen size (p < 0.05), and 11% lower than the final follow-up endobag volume (p < 0.01). The automated method required minimal user interaction; it was fast and used a single set of parameters for all subjects. Intra-observer and manual vs. automated variability of measured volumes were 0.35 ± 2.11 and 0.07 ± 3.04 mL, respectively. Deformable surface models were used to quantify AAA size and showed that EVAS system devices tended to expand the sac lumen size.

  6. Chronic Kidney Disease Is Positively and Diabetes Mellitus Is Negatively Associated with Abdominal Aortic Aneurysm

    PubMed Central

    Uchida, Haruhito A.; Kakio, Yuki; Umebayashi, Ryoko; Okuyama, Yuka; Fujii, Yasuhiro; Ozawa, Susumu; Yoshida, Masashi; Oshima, Yu; Sano, Shunji; Wada, Jun

    2016-01-01

    Background and Aims Chronic kidney disease (CKD) and diabetes mellitus (DM) are considered as risk factors for cardiovascular diseases. The purpose of this study was to clarify the relationship of CKD and DM with the presence of abdominal aortic aneurysm (AAA). Methods We enrolled 261 patients with AAA (AAA+) and age-and-sex matched 261 patients without AAA (AAA-) at two hospitals between 2008 and 2014, and examined the association between the risk factors and the presence of AAA. Furthermore, in order to investigate the prevalence of AAA in each group, we enrolled 1126 patients with CKD and 400 patients with DM. Results The presence of CKD in patients with AAA+ was significantly higher than that in patients with AAA- (AAA+; 65%, AAA-; 52%, P = 0.004). The presence of DM in patients with AAA+ was significantly lower than that in patients with AAA- (AAA+; 17%, AAA-; 35%, P < 0.001). A multivariate logistic regression analysis demonstrated that hypertension, ischemic heart disease and CKD were independent determinants, whereas, DM was a negatively independent determinant, for the presence of AAA. The prevalence of AAA in patients with CKD 65 years old and above was 5.1%, whereas, that in patients with DM 65 years old and above was only 0.6%. Conclusion CKD is a positively associated with the presence of AAA. In contrast, DM is a negatively associated with the presence of AAA in Japanese population. PMID:27764090

  7. Fruit Intake and Abdominal Aortic Calcification in Elderly Women: A Prospective Cohort Study

    PubMed Central

    Bondonno, Nicola P.; Lewis, Joshua R.; Prince, Richard L.; Lim, Wai H.; Wong, Germaine; Schousboe, John T.; Woodman, Richard J.; Kiel, Douglas P.; Bondonno, Catherine P.; Ward, Natalie C.; Croft, Kevin D.; Hodgson, Jonathan M.

    2016-01-01

    Cardiovascular disease (CVD) is the leading cause of death worldwide. There is a consistent inverse relationship between fruit intake with CVD events and mortality in cross-sectional and prospective observational studies, but the relationship of fruit intake with measurements of atherosclerosis in humans is less clear. Nutritional effects on abdominal aortic calcification (AAC), a marker for subclinical intimal and medial atherosclerotic vascular disease, have not been studied previously. The aim of this study was to examine the cross-sectional relationship of total and individual fruit (apple, pear, orange and other citrus, and banana) intake with AAC, scored between 0 and 24. The current study assessed baseline data for a cohort of 1052 women over 70 years of age who completed both a food frequency questionnaire assessing fruit intake, and underwent AAC measurement using dual energy X-ray absorptiometry. AAC scores were significantly negatively correlated with total fruit and apple intakes (p < 0.05), but not with pear, orange or banana intakes (p > 0.25). In multivariable-adjusted logistic regression, each standard deviation (SD; 50 g/day) increase in apple intake was associated with a 24% lower odds of having severe AAC (AAC score >5) (odd ratio OR): 0.76 (0.62, 0.93), p = 0.009). Total and other individual fruit intake were not associated with increased odds of having severe AAC. Apple but not total or other fruit intake is independently negatively associated with AAC in older women. PMID:26978394

  8. Translational Relevance and Recent Advances of Animal Models of Abdominal Aortic Aneurysm.

    PubMed

    Sénémaud, Jean; Caligiuri, Giuseppina; Etienne, Harry; Delbosc, Sandrine; Michel, Jean-Baptiste; Coscas, Raphaël

    2017-03-01

    Human abdominal aortic aneurysm (AAA) pathophysiology is not yet completely understood. In conductance arteries, the insoluble extracellular matrix, synthesized by vascular smooth muscle cells, assumes the function of withstanding the intraluminal arterial blood pressure. Progressive loss of this function through extracellular matrix proteolysis is a main feature of AAAs. As most patients are now treated via endovascular approaches, surgical AAA specimens have become rare. Animal models provide valuable complementary insights into AAA pathophysiology. Current experimental AAA models involve induction of intraluminal dilation (nondissecting AAAs) or a contained intramural rupture (dissecting models). Although the ideal model should reproduce the histological characteristics and natural history of the human disease, none of the currently available animal models perfectly do so. Experimental models try to represent the main pathophysiological determinants of AAAs: genetic or acquired defects in extracellular matrix, loss of vascular smooth muscle cells, and innate or adaptive immune response. Nevertheless, most models are characterized by aneurysmal stabilization and healing after a few weeks because of cessation of the initial stimulus. Recent studies have focused on ways to optimize existing models to allow continuous aneurysmal growth. This review aims to discuss the relevance and recent advances of current animal AAA models.

  9. The Relationship Between Pulsatile Flow Impingement and Intraluminal Thrombus Deposition in Abdominal Aortic Aneurysms.

    PubMed

    Lozowy, Richard J; Kuhn, David C S; Ducas, Annie A; Boyd, April J

    2017-03-01

    Direct numerical simulations were performed on four patient-specific abdominal aortic aneurysm (AAA) geometries and the resulting pulsatile blood flow dynamics were compared to aneurysm shape and correlated with intraluminal thrombus (ILT) deposition. For three of the cases, turbulent vortex structures impinged/sheared along the anterior wall and along the posterior wall a zone of recirculating blood formed. Within the impingement region the AAA wall was devoid of ILT and remote to this region there was an accumulation of ILT. The high wall shear stress (WSS) caused by the impact of vortexes is thought to prevent the attachment of ILT. WSS from impingement is comparable to peak-systolic WSS in a normal-sized aorta and therefore may not damage the wall. Expansion occurred to a greater extent in the direction of jet impingement and the wall-normal force from the continuous impact of vortexes may contribute to expansion. It was shown that the impingement region has low oscillatory shear index (OSI) and recirculation zones can have either low or high OSI. No correlation could be identified between OSI and ILT deposition since different flow dynamics can have similar OSI values.

  10. A Review of Computational Methods to Predict the Risk of Rupture of Abdominal Aortic Aneurysms.

    PubMed

    Canchi, Tejas; Kumar, S D; Ng, E Y K; Narayanan, Sriram

    2015-01-01

    Computational methods have played an important role in health care in recent years, as determining parameters that affect a certain medical condition is not possible in experimental conditions in many cases. Computational fluid dynamics (CFD) methods have been used to accurately determine the nature of blood flow in the cardiovascular and nervous systems and air flow in the respiratory system, thereby giving the surgeon a diagnostic tool to plan treatment accordingly. Machine learning or data mining (MLD) methods are currently used to develop models that learn from retrospective data to make a prediction regarding factors affecting the progression of a disease. These models have also been successful in incorporating factors such as patient history and occupation. MLD models can be used as a predictive tool to determine rupture potential in patients with abdominal aortic aneurysms (AAA) along with CFD-based prediction of parameters like wall shear stress and pressure distributions. A combination of these computer methods can be pivotal in bridging the gap between translational and outcomes research in medicine. This paper reviews the use of computational methods in the diagnosis and treatment of AAA.

  11. Fluid-Structure Interaction in Abdominal Aortic Aneurysm: Effect of Modeling Techniques.

    PubMed

    Lin, Shengmao; Han, Xinwei; Bi, Yonghua; Ju, Siyeong; Gu, Linxia

    2017-01-01

    In this work, the impact of modeling techniques on predicting the mechanical behaviors of abdominal aortic aneurysm (AAA) is systematically investigated. The fluid-structure interaction (FSI) model for simultaneously capturing the transient interaction between blood flow dynamics and wall mechanics was compared with its simplified techniques, that is, computational fluid dynamics (CFD) or computational solid stress (CSS) model. Results demonstrated that CFD exhibited relatively smaller vortexes and tends to overestimate the fluid wall shear stress, compared to FSI. On the contrary, the minimal differences in wall stresses and deformation were observed between FSI and CSS models. Furthermore, it was found that the accuracy of CSS prediction depends on the applied pressure profile for the aneurysm sac. A large pressure drop across AAA usually led to the underestimation of wall stresses and thus the AAA rupture. Moreover, the assumed isotropic AAA wall properties, compared to the anisotropic one, will aggravate the difference between the simplified models with the FSI approach. The present work demonstrated the importance of modeling techniques on predicting the blood flow dynamics and wall mechanics of the AAA, which could guide the selection of appropriate modeling technique for significant clinical implications.

  12. Role of preoperative radionuclide ejection fraction in direct abdominal aortic aneurysm repair

    SciTech Connect

    Kazmers, A.; Cerqueira, M.D.; Zierler, R.E.

    1988-08-01

    Preoperative radionuclide ventriculography was performed in 60 patients to assess whether such testing could define those at increased risk after direct abdominal aortic aneurysm (AAA) repair. None of the patients had prophylactic coronary artery reconstruction to reduce the risk of AAA repair despite angina in 27% and previous myocardial infarction (MI) in 42%. The mean ejection fraction (EF) was 52% +/- 15% (range 14% to 78%). Low EF (normal greater than 50%) was present in 40%, whereas ventricular wall motion abnormalities were present in 39% of patients. The overall perioperative (30-day) mortality rate was 5%. MI occurred in 7% within 30 postoperative days; none was fatal. Life-table analysis revealed that overall survival after AAA repair was significantly lower in patients with an EF of 50% or less (p less than 0.025, Mantel-Cox) during a follow-up of 20.1 +/- 11.9 months. Overall survival differences were even more striking for those with an EF of 35% or less (p = 0.003, Mantel-Cox). There was a marked difference in the cumulative mortality rate during follow-up, being 50% in those patients with an EF of 35% or less (n = 10) compared with 14% in those with an EF greater than 35% (n = 50, p = 0.036, Fisher exact test). There was no statistical difference in the incidence of perioperative MI or perioperative death for those with an EF of 35% or less vs EF greater than 35%. 50 references.

  13. Pulsatile non-Newtonian haemodynamics in a 3D bifurcating abdominal aortic aneurysm model.

    PubMed

    Ma, J; Turan, A

    2011-08-01

    Numerical prediction of non-Newtonian blood flow in a 3D abdominal aortic aneurysm bifurcating model is carried out. The non-Newtonian Carreau model is used to characterise the shear thinning behaviour of the human blood. A physical inlet velocity waveform incorporating a radial velocity distribution reasonably representative of a practical case configuration is employed. Case studies subject to both equal and unequal outlet pressures at iliac bifurcations are presented to display convincingly the downstream pressure influences on the flow behaviour within the aneurysm. Simulations indicate that the non-Newtonian aspects of the blood cannot at all be neglected or given a cursory treatment. The wall shear stress (WSS) is found to change significantly at both the proximal and distal ends of the aneurysm. At the peak systole, the WSS is peak around the bifurcation point, whereas the WSS becomes zero in the bifurcation point. Differential downstream pressure fields display significant effects regarding the flow evolution in the iliac arteries, whereas little or no effects are observed directly on the flow details in the aneurysm.

  14. Type II Endoleak After Endovascular Repair of Abdominal Aortic Aneurysm: Effectiveness of Embolization

    SciTech Connect

    Nevala, Terhi; Biancari, Fausto; Manninen, Hannu; Aho, Pekka-Sakari; Matsi, Pekka; Maekinen, Kimmo; Roth, Wolf-Dieter; Yloenen, Kari; Lepaentalo, Mauri; Peraelae, Jukka

    2010-04-15

    The purpose of this study was to report our experience in treating type II endoleaks after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms. Two hundred eighteen patients underwent EVAR with a Zenith stent-graft from January 2000 to December 2005. During a follow-up period of 4.5 {+-} 2.3 years, solely type II endoleak was detected in 47 patients (22%), and 14 of them underwent secondary interventions to correct this condition. Ten patients had transarterial embolization, and four patients had translumbar/transabdominal embolization. The embolization materials used were coils, thrombin, gelatin, Onyx (ethylene-vinyl alcohol copolymer), and glue. Disappearance of the endoleak without enlargement of the aneurysm sac after the first secondary intervention was achieved in only five of these patients (5/13). One patient without surveillance imaging was excluded from analyses of clinical success. After additional interventions in four patients and the spontaneous disappearance of type II endoleak in two patients, overall clinical success was achieved in eight patients (8/12). One patient did not have surveillance imaging after the second secondary intervention. Clinical success after the first secondary intervention was achieved in two patients (2/9) in the transarterial embolization group and three patients (3/4) in the translumbar embolization group. The results of secondary interventions for type II endoleak are unsatisfactory. Although the small number of patients included in this study prevents reliable comparisons between groups, the results seem to favor direct translumbar embolization in comparison to transarterial embolization.

  15. Determining the influence of calcification on the failure properties of abdominal aortic aneurysm (AAA) tissue.

    PubMed

    O'Leary, Siobhan A; Mulvihill, John J; Barrett, Hilary E; Kavanagh, Eamon G; Walsh, Michael T; McGloughlin, Tim M; Doyle, Barry J

    2015-02-01

    Varying degrees of calcification are present in most abdominal aortic aneurysms (AAAs). However, their impact on AAA failure properties and AAA rupture risk is unclear. The aim of this work is evaluate and compare the failure properties of partially calcified and predominantly fibrous AAA tissue and investigate the potential reasons for failure. Uniaxial mechanical testing was performed on AAA samples harvested from 31 patients undergoing open surgical repair. Individual tensile samples were divided into two groups: fibrous (n=31) and partially calcified (n=38). The presence of calcification was confirmed by fourier transform infrared spectroscopy (FTIR). A total of 69 mechanical tests were performed and the failure stretch (λf), failure stress (σf) and failure tension (Tf) were recorded for each test. Following mechanical testing, the failure sites of a subset of both tissue types were examined using scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDS) to investigate the potential reasons for failure. It has been shown that the failure properties of partially calcified tissue are significantly reduced compared to fibrous tissue and SEM and EDS results suggest that the junction between a calcification deposit and the fibrous matrix is highly susceptible to failure. This study implicates the presence of calcification as a key player in AAA rupture risk and provides further motivation for the development of non-invasive methods of measuring calcification.

  16. Quantitative HDL Proteomics Identifies Peroxiredoxin-6 as a Biomarker of Human Abdominal Aortic Aneurysm.

    PubMed

    Burillo, Elena; Jorge, Inmaculada; Martínez-López, Diego; Camafeita, Emilio; Blanco-Colio, Luis Miguel; Trevisan-Herraz, Marco; Ezkurdia, Iakes; Egido, Jesús; Michel, Jean-Baptiste; Meilhac, Olivier; Vázquez, Jesús; Martin-Ventura, Jose Luis

    2016-12-09

    High-density lipoproteins (HDLs) are complex protein and lipid assemblies whose composition is known to change in diverse pathological situations. Analysis of the HDL proteome can thus provide insight into the main mechanisms underlying abdominal aortic aneurysm (AAA) and potentially detect novel systemic biomarkers. We performed a multiplexed quantitative proteomics analysis of HDLs isolated from plasma of AAA patients (N = 14) and control study participants (N = 7). Validation was performed by western-blot (HDL), immunohistochemistry (tissue), and ELISA (plasma). HDL from AAA patients showed elevated expression of peroxiredoxin-6 (PRDX6), HLA class I histocompatibility antigen (HLA-I), retinol-binding protein 4, and paraoxonase/arylesterase 1 (PON1), whereas α-2 macroglobulin and C4b-binding protein were decreased. The main pathways associated with HDL alterations in AAA were oxidative stress and immune-inflammatory responses. In AAA tissue, PRDX6 colocalized with neutrophils, vascular smooth muscle cells, and lipid oxidation. Moreover, plasma PRDX6 was higher in AAA (N = 47) than in controls (N = 27), reflecting increased systemic oxidative stress. Finally, a positive correlation was recorded between PRDX6 and AAA diameter. The analysis of the HDL proteome demonstrates that redox imbalance is a major mechanism in AAA, identifying the antioxidant PRDX6 as a novel systemic biomarker of AAA.

  17. Percutaneous Treatment of Sac Rupture in Abdominal Aortic Aneurysms Previously Excluded with Endovascular Repair (EVAR)

    SciTech Connect

    Lagana, Domenico Mangini, Monica Fontana, Federico; Nicotera, Paolo; Carrafiello, Gianpaolo; Fugazzola, Carlo

    2009-01-15

    The purpose of this study was to assess the feasibility and effectiveness of percutaneous endovascular repair of ruptured abdominal aortic aneurysms (AAAs) previously treated by EVAR. In the last year, two male patients with AAAs, treated 8 and 23 months ago with bifurcated stent-graft, were observed because of lumbar pain and hemorragic shock. Multidetector computed tomography (MDCT) showed a retroperitoneal hematoma; in both cases a type III endoleak was detected, in one case associated with a type II endoleak from the iliolumbar artery. The procedures were performed in the theater, in emergency. Type II endoleak was treated with transcatheter superselective glue injection; type III endoleaks were excluded by a stent-graft extension. The procedures were successful in both patients, with immediate hemodynamic stabilization. MDCT after the procedure showed complete exclusion of the aneurysms. In conclusion, endovascular treatment is a safe and feasible option for the treatment of ruptured AAAs previously treated by EVAR; this approach allows avoidance of surgical conversion, which is technical very challenging, with a high morbidity and mortality rate.

  18. Local influence of calcifications on the wall mechanics of abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    de Putter, Sander; van de Vosse, Frans N.; Breeuwer, Marcel; Gerritsen, Frans A.

    2006-03-01

    Finite element wall stress simulations on patient-specific models of abdominal aortic aneurysm (AAA) may provide a better rupture risk predictor than the currently used maximum transverse diameter. Calcifications in the wall of AAA lead to a higher maximum wall stress and thus may lead to an elevated rupture risk. The reported material properties for calcifications and the material properties actually used for simulations show great variation. Previous studies have focused on simplified modelling of the calcification shapes within a realistic aneurysm shape. In this study we use an accurate representation of the calcification geometry and a simplified model for the AAA. The objective of this approach is to investigate the influence of the calcification geometry, the material properties and the modelling approach for the computed peak wall stress. For four realistic calcification shapes from standard clinical CT images of AAA, we performed simulations with three distinct modelling approaches, at five distinct elasticity settings. The results show how peak wall stress is sensitive to the material properties of the calcifications. For relatively elastic calcifications, the results from the different modelling approaches agree. Also, for relatively elastic calcifications the computed wall stress in the tissue surrounding the calcifications shows to be insensitive to the exact calcification geometry. For stiffer calcifications the different modelling approaches and the different geometries lead to significantly different results. We conclude that an important challenge for future research is accurately estimating the material properties and the rupture potential of the AAA wall including calcifications.

  19. 3D visualization of strain in abdominal aortic aneurysms based on navigated ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Brekken, Reidar; Kaspersen, Jon Harald; Tangen, Geir Arne; Dahl, Torbjørn; Hernes, Toril A. N.; Myhre, Hans Olav

    2007-03-01

    The criterion for recommending treatment of an abdominal aortic aneurysm is that the diameter exceeds 50-55 mm or shows a rapid increase. Our hypothesis is that a more accurate prediction of aneurysm rupture is obtained by estimating arterial wall strain from patient specific measurements. Measuring strain in specific parts of the aneurysm reveals differences in load or tissue properties. We have previously presented a method for in vivo estimation of circumferential strain by ultrasound. In the present work, a position sensor attached to the ultrasound probe was used for combining several 2D ultrasound sectors into a 3D model. The ultrasound was registered to a computed-tomography scan (CT), and the strain values were mapped onto a model segmented from these CT data. This gave an intuitive coupling between anatomy and strain, which may benefit both data acquisition and the interpretation of strain. In addition to potentially provide information relevant for assessing the rupture risk of the aneurysm in itself, this model could be used for validating simulations of fluid-structure interactions. Further, the measurements could be integrated with the simulations in order to increase the amount of patient specific information, thus producing a more reliable and accurate model of the biomechanics of the individual aneurysm. This approach makes it possible to extract several parameters potentially relevant for predicting rupture risk, and may therefore extend the basis for clinical decision making.

  20. Adaptive Flow Simulation of Turbulence in Subject-Specific Abdominal Aortic Aneurysm on Massively Parallel Computers

    NASA Astrophysics Data System (ADS)

    Sahni, Onkar; Jansen, Kenneth; Shephard, Mark; Taylor, Charles

    2007-11-01

    Flow within the healthy human vascular system is typically laminar but diseased conditions can alter the geometry sufficiently to produce transitional/turbulent flows in regions focal (and immediately downstream) of the diseased section. The mean unsteadiness (pulsatile or respiratory cycle) further complicates the situation making traditional turbulence simulation techniques (e.g., Reynolds-averaged Navier-Stokes simulations (RANSS)) suspect. At the other extreme, direct numerical simulation (DNS) while fully appropriate can lead to large computational expense, particularly when the simulations must be done quickly since they are intended to affect the outcome of a medical treatment (e.g., virtual surgical planning). To produce simulations in a clinically relevant time frame requires; 1) adaptive meshing technique that closely matches the desired local mesh resolution in all three directions to the highly anisotropic physical length scales in the flow, 2) efficient solution algorithms, and 3) excellent scaling on massively parallel computers. In this presentation we will demonstrate results for a subject-specific simulation of an abdominal aortic aneurysm using stabilized finite element method on anisotropically adapted meshes consisting of O(10^8) elements over O(10^4) processors.

  1. 3D analysis of vortical structures in an abdominal aortic aneurysm by stereoscopic PIV

    NASA Astrophysics Data System (ADS)

    Deplano, Valérie; Guivier-Curien, Carine; Bertrand, Eric

    2016-11-01

    The present work presents an experimental in vitro three-dimensional analysis of the flow dynamics in an abdominal aortic aneurysm (AAA) through stereoscopic particle image velocimetry (SPIV) measurements. The experimental set-up mimics the pathophysiological context involving a shear thinning blood analogue fluid, compliant AAA and aorto-iliac bifurcation walls and controlled inlet and outlet flow rate and pressure waveforms as well as working fluid temperature. SPIV was carefully calibrated and conducted to assess the three velocity components in the AAA volume. For the first time in the literature, the 3D vortex ring genesis, propagation, and vanishing in the AAA bulge are experimentally described and quantified. In comparison with classical 2-component PIV measurements (2C PIV), the third component of the velocity vector was shown to be of importance in such a geometry, especially, during the deceleration phase of the flow rate. The 3D velocity magnitude reached up more than 20 % of the 2D one showing that 2C PIV are definitively not accurate enough to provide a complete description of flow behaviour in an AAA. In addition to potential clinical implications of a full 3D vortex ring description in AAA evolution, the 3D in vitro experimental quantification of the flow dynamics carried out in the present study offers an interesting tool for the validation of fluid-structure interaction numerical studies dealing with AAA.

  2. Model-based segmentation of abdominal aortic aneurysms in CTA images

    NASA Astrophysics Data System (ADS)

    de Bruijne, Marleen; van Ginneken, Bram; Niessen, Wiro J.; Loog, Marco; Viergever, Max A.

    2003-05-01

    Segmentation of thrombus in abdominal aortic aneurysms is complicated by regions of low boundary contrast and by the presence of many neighboring structures in close proximity to the aneurysm wall. We present an automated method that is similar to the well known Active Shape Models (ASM), combining a three-dimensional shape model with a one-dimensional boundary appearance model. Our contribution is twofold: we developed a non-parametric appearance modeling scheme that effectively deals with a highly varying background, and we propose a way of generalizing models of curvilinear structures from small training sets. In contrast with the conventional ASM approach, the new appearance model trains on both true and false examples of boundary profiles. The probability that a given image profile belongs to the boundary is obtained using k nearest neighbor (kNN) probability density estimation. The performance of this scheme is compared to that of original ASMs, which minimize the Mahalanobis distance to the average true profile in the training set. The generalizability of the shape model is improved by modeling the objects axis deformation independent of its cross-sectional deformation. A leave-one-out experiment was performed on 23 datasets. Segmentation using the kNN appearance model significantly outperformed the original ASM scheme; average volume errors were 5.9% and 46% respectively.

  3. Inhibitory Effect of Statins on Inflammation-Related Pathways in Human Abdominal Aortic Aneurysm Tissue

    PubMed Central

    Yoshimura, Koichi; Nagasawa, Ayako; Kudo, Junichi; Onoda, Masahiko; Morikage, Noriyasu; Furutani, Akira; Aoki, Hiroki; Hamano, Kimikazu

    2015-01-01

    HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitors (statins) have been suggested to attenuate abdominal aortic aneurysm (AAA) growth. However, the effects of statins in human AAA tissues are not fully elucidated. The aim of this study was to investigate the direct effects of statins on proinflammatory molecules in human AAA walls in ex vivo culture. Simvastatin strongly inhibited the activation of nuclear factor (NF)-κB induced by tumor necrosis factor (TNF)-α in human AAA walls, but showed little effect on c-jun N-terminal kinase (JNK) activation. Simvastatin, as well as pitavastatin significantly reduced the secretion of matrix metalloproteinase (MMP)-9, monocyte chemoattractant protein (MCP)-2 and epithelial neutrophil-activating peptide (CXCL5) under both basal and TNF-α-stimulated conditions. Similar to statins, the Rac1 inhibitor NSC23766 significantly inhibited the activation of NF-κB, accompanied by a decreased secretion of MMP-9, MCP-2 and CXCL5. Moreover, the effect of simvastatin and the JNK inhibitor SP600125 was additive in inhibiting the secretion of MMP-9, MCP-2 and CXCL5. These findings indicate that statins preferentially inhibit the Rac1/NF-κB pathway to suppress MMP-9 and chemokine secretion in human AAA, suggesting a mechanism for the potential effect of statins in attenuating AAA progression. PMID:25993292

  4. Meta-Analysis of Abdominal Aortic Aneurysm in Patients With Coronary Artery Disease.

    PubMed

    Elkalioubie, Ahmed; Haulon, Stephan; Duhamel, Alain; Rosa, Mickael; Rauch, Antoine; Staels, Bart; Susen, Sophie; Van Belle, Eric; Dupont, Annabelle

    2015-11-01

    The high coronary artery disease (CAD) prevalence in patients with abdominal aortic aneurysm (AAA) is well known. However, the inverse relation has been little explored. We present, based on a systematic review and meta-analysis of the published evidence, a critical appraisal of the issue of AAA prevalence and also AAA predictive risk factors in patients with CAD, comparing it with AAA prevalence in subjects without CAD. A total of 22 studies involving 13,388 patients with CAD met the inclusion criteria. Overall, AAA prevalence in patients with CAD was 8.4% (95% confidence interval [CI] 6.9 to 10.3), significantly higher than in subjects without CAD (odds ratio [OR] 2.42, 95% CI 2.08 to 2.81). Pooled analysis revealed that smoking, arterial hypertension, and concomitant carotid artery stenosis were significantly associated with AAA in patients with CAD (OR 1.72, 95% CI 1.14 to 2.61; OR 1.57, 95% CI 1.06 to 2.35; OR 2.14, 95% CI 1.20 to 3.79, respectively). In patients with CAD, AAA prevalence tended to be higher with concomitant peripheral artery disease (OR 2.66, 95% CI 0.82 to 8.61, p = 0.08). In conclusion, AAA prevalence was significantly higher in patients with CAD versus subjects without CAD.

  5. Frequency of abdominal aortic aneurysm in patients undergoing coronary artery bypass grafting.

    PubMed

    Dupont, Annabelle; Elkalioubie, Ahmed; Juthier, Francis; Tagzirt, Madjid; Vincentelli, André; Le Tourneau, Thierry; Haulon, Stéphan; Deklunder, Ghislaine; Breyne, Joke; Susen, Sophie; Marechaux, Sylvestre; Pinet, Florence; Jude, Brigitte

    2010-06-01

    The aims of this study were to clarify the prevalence and the risk factors for unsuspected abdominal aortic aneurysm (AAA) in patients who underwent coronary artery bypass grafting for severe coronary artery disease and to identify the most at risk patients for AAA. Among 217 patients (189 men, mean age 64 +/- 11 years), asymptomatic AAAs, as prospectively identified by echocardiography, were found in 15 patients (6.9%). All patients with AAAs were men and smokers or past smokers. Factors significantly associated by univariate analysis with asymptomatic AAA presence were smoking (p = 0.003), symptomatic peripheral artery disease (p = 0.006), significant carotid artery stenosis (p = 0.007), and larger femoral and popliteal diameters (p = 0.008 and p = 0.0012, respectively). The other classic demographic, clinical, and biologic features were equally distributed among patients. In conclusion, in patients who underwent coronary artery bypass grafting who were men and aged <75 years with smoking histories, the prevalence of AAA was as high as 24% when they had concomitant peripheral arterial disease and/or carotid artery stenosis (vs 4.4% in the absence of either condition, p = 0.007), justifying consideration of AAA screening in this subgroup of in-hospital patients.

  6. Abdominal Aortic Hemodynamics in Intermittent Claudication Patients at Rest and During Dynamic Pedaling Exercise

    PubMed Central

    Cheng, Christopher P.; Taylor, Charles A.; Dalman, Ronald L.

    2015-01-01

    Introduction Lower extremity exercise has been shown to eliminate adverse hemodynamics conditions, such as low and oscillating blood flow and wall shear stress, in the abdominal aortas of healthy young and older adults. Methods We use cine phase-contrast magnetic resonance imaging and a custom MRI-compatible exercise cycle to quantify hemodynamic changes due to pedaling exercise in patients diagnosed with intermittent claudication. Results and Conclusions With only an average heart increase of 35±18% and exercise workload of 36±16 Watts, the patients experienced approximately 3- and 6-fold increases in blood flow, and 4- and 16-fold increases in wall shear stress at the supraceliac and infrarenal aortic locations, respectively. Also, all oscillations in flow and shear stress at rest were eliminated with exercise. Claudication patients experience 3 to 4-fold lower oscillations in flow and shear stress at rest as compared to healthy age-matched controls, likely due to reduced distal arterial compliance as a result of distal atherosclerosis. The magnitude of flow and shear oscillatory indices may be good indicators of distal arterial compliance and health, and may provide predictive power for the efficacy of focal interventions. PMID:26315797

  7. Probabilistic noninvasive prediction of wall properties of abdominal aortic aneurysms using Bayesian regression.

    PubMed

    Biehler, Jonas; Kehl, Sebastian; Gee, Michael W; Schmies, Fadwa; Pelisek, Jaroslav; Maier, Andreas; Reeps, Christian; Eckstein, Hans-Henning; Wall, Wolfgang A

    2017-02-01

    Multiple patient-specific parameters, such as wall thickness, wall strength, and constitutive properties, are required for the computational assessment of abdominal aortic aneurysm (AAA) rupture risk. Unfortunately, many of these quantities are not easily accessible and could only be determined by invasive procedures, rendering a computational rupture risk assessment obsolete. This study investigates two different approaches to predict these quantities using regression models in combination with a multitude of noninvasively accessible, explanatory variables. We have gathered a large dataset comprising tensile tests performed with AAA specimens and supplementary patient information based on blood analysis, the patients medical history, and geometric features of the AAAs. Using this unique database, we harness the capability of state-of-the-art Bayesian regression techniques to infer probabilistic models for multiple quantities of interest. After a brief presentation of our experimental results, we show that we can effectively reduce the predictive uncertainty in the assessment of several patient-specific parameters, most importantly in thickness and failure strength of the AAA wall. Thereby, the more elaborate Bayesian regression approach based on Gaussian processes consistently outperforms standard linear regression. Moreover, our study contains a comparison to a previously proposed model for the wall strength.

  8. The putative role of autophagy in the pathogenesis of abdominal aortic aneurysms.

    PubMed

    Ramadan, Azza; Al-Omran, Mohammed; Verma, Subodh

    2017-02-01

    Abdominal aortic aneurysms (AAA) are a significant cause of worldwide mortality and morbidity. While the histopathological characteristics of AAA are well documented, the cellular and molecular mechanisms involved in the pathogenesis of AAA are not entirely understood. Autophagy is a highly conserved basal cellular process in eukaryotic cells that involves the turnover of organelles and proteins. It is also activated as an adaptive response to stressful conditions to promote cell survival. While autophagy typically promotes pro-survival processes, it can sometimes lead to cellular demise. Preclinical studies have revealed autophagy to be a protective mechanism in certain vascular diseases with several autophagy-related genes reported to be markedly upregulated in human aneurysmal tissue. The role autophagy plays in the pathogenesis of AAA, however, remains poorly defined. In this review, we discuss the putative role of autophagy in AAA by reviewing several in vitro and in vivo studies that address the functional significance of autophagy in cells that are involved in the pathophysiology of AAA, amongst which are macrophages, smooth muscle and endothelial cells.

  9. Trace elements in the wall of abdominal aortic aneurysms with and without coexisting iliac artery aneurysms.

    PubMed

    Ziaja, Damian; Chudek, Jerzy; Sznapka, Mariola; Kita, Andrzej; Biolik, Grzegorz; Sieroń-Stołtny, Karolina; Pawlicki, Krzysztof; Domalik, Jolanta; Ziaja, Krzysztof

    2015-06-01

    Iliac artery aneurysms (IAA) and abdominal aortic aneurysms (AAA) frequently coexist. It remains unknown whether the content of trace elements in AAA walls depends on the coexistence of IAAs. The aim of this study was to compare the content of selected trace elements in AAA walls depending on the coexistence of IAAs. The content of trace elements was assessed in samples of AAA walls harvested intraoperatively in 19 consecutive patients. In the studied group, coexisting IAAs were diagnosed in 11 out of the 19 patients with AAA. The coexistence of IAAs was associated with a slightly lower content of nickel (0.28 (0.15-0.40) vs. 0.32 (0-0.85) mg/g; p = 0.09) and a significantly higher content of cadmium (0.71 (0.26-1.17) vs. 0.25 (0.20-0.31) mg/g; p = 0.04) in AAA walls. The levels of the remaining studied elements, copper, zinc, manganese, magnesium and calcium, were comparable. The elevated levels of cadmium in the walls of AAA coexisting with IAAs may suggest an impact of the accumulation of this trace element on the greater damage of the iliac artery wall.

  10. Association of osteocalcin and abdominal aortic calcification in older women: the study of osteoporotic fractures.

    PubMed

    Parker, Benjamin D; Bauer, Douglas C; Ensrud, Kristine E; Ix, Joachim H

    2010-03-01

    Osteocalcin (OC) is produced by osteoblasts and vascular smooth muscle cells. In animal models, serum OC levels are strongly correlated with vascular calcium content, however, the association of OC with vascular calcification in humans is uncertain. The Study of Osteoporotic Fractures (SOF) enrolled community-living women, age > or =65 years. The present study included a subsample of 363 randomly selected SOF participants. Serum total OC was measured by ELISA, and abdominal aortic calcification (AAC) was evaluated on lateral lumbar radiographs. We examined the cross-sectional association between serum OC and AAC. The mean serum OC level was 24 +/- 11 ng/ml and AAC was present in 188 subjects (52%). We observed no association of OC and AAC in either unadjusted or adjusted analyses. For example, each standard deviation higher OC level was associated with an odds ratio (OR) for AAC prevalence (AAC score >0) near unity (OR = 1.06; 95% CI, 0.82-1.36) in models adjusted for CVD risk factors. Further adjustment for intact parathyroid hormone, bone-specific alkaline phosphatase, 25-hydroxyvitamin D, and hip and spine bone mineral density did not materially change the results (OR = 1.22; 95% CI, 0.86-1.75). Similarly, higher OC levels were not associated with severity of AAC (P = 0.87). In conclusion, among community-living older women, serum OC is not associated with AAC. These findings suggest that serum OC levels may more closely reflect bone formation than vascular calcification in humans.

  11. Fluid-Structure Interaction in Abdominal Aortic Aneurysm: Effect of Modeling Techniques

    PubMed Central

    Lin, Shengmao; Han, Xinwei; Bi, Yonghua; Ju, Siyeong

    2017-01-01

    In this work, the impact of modeling techniques on predicting the mechanical behaviors of abdominal aortic aneurysm (AAA) is systematically investigated. The fluid-structure interaction (FSI) model for simultaneously capturing the transient interaction between blood flow dynamics and wall mechanics was compared with its simplified techniques, that is, computational fluid dynamics (CFD) or computational solid stress (CSS) model. Results demonstrated that CFD exhibited relatively smaller vortexes and tends to overestimate the fluid wall shear stress, compared to FSI. On the contrary, the minimal differences in wall stresses and deformation were observed between FSI and CSS models. Furthermore, it was found that the accuracy of CSS prediction depends on the applied pressure profile for the aneurysm sac. A large pressure drop across AAA usually led to the underestimation of wall stresses and thus the AAA rupture. Moreover, the assumed isotropic AAA wall properties, compared to the anisotropic one, will aggravate the difference between the simplified models with the FSI approach. The present work demonstrated the importance of modeling techniques on predicting the blood flow dynamics and wall mechanics of the AAA, which could guide the selection of appropriate modeling technique for significant clinical implications. PMID:28321413

  12. Fluid-structure interaction in abdominal aortic aneurysms: Structural and geometrical considerations

    NASA Astrophysics Data System (ADS)

    Mesri, Yaser; Niazmand, Hamid; Deyranlou, Amin; Sadeghi, Mahmood Reza

    2015-08-01

    Rupture of the abdominal aortic aneurysm (AAA) is the result of the relatively complex interaction of blood hemodynamics and material behavior of arterial walls. In the present study, the cumulative effects of physiological parameters such as the directional growth, arterial wall properties (isotropy and anisotropy), iliac bifurcation and arterial wall thickness on prediction of wall stress in fully coupled fluid-structure interaction (FSI) analysis of five idealized AAA models have been investigated. In particular, the numerical model considers the heterogeneity of arterial wall and the iliac bifurcation, which allows the study of the geometric asymmetry due to the growth of the aneurysm into different directions. Results demonstrate that the blood pulsatile nature is responsible for emerging a time-dependent recirculation zone inside the aneurysm, which directly affects the stress distribution in aneurismal wall. Therefore, aneurysm deviation from the arterial axis, especially, in the lateral direction increases the wall stress in a relatively nonlinear fashion. Among the models analyzed in this investigation, the anisotropic material model that considers the wall thickness variations, greatly affects the wall stress values, while the stress distributions are less affected as compared to the uniform wall thickness models. In this regard, it is confirmed that wall stress predictions are more influenced by the appropriate structural model than the geometrical considerations such as the level of asymmetry and its curvature, growth direction and its extent.

  13. Resolved Abdominal Aortic Aneurysms Following Stent Graft Treatment: A Report of Five Cases

    SciTech Connect

    Rimon, Uri; Garniek, Alexander; Golan, Gil; Bensaid, Paul; Galili, Yair; Schneiderman, Jacob; Morag, Benyamina

    2004-03-15

    Complete aneurysm resolution is the hallmark of successful endoluminal stent-graft treatment. We describe 5 patients in whom an abdominal aortic aneurysm (AAA) disappeared completely at mid-term follow-up after endovascular stent-graft placement. We reviewed 45 patients (43 men and 2 women) who underwent AAA repair using an endovascular technique, from April 1997 to December 2001. Mean AAA diameter was 58.3 mm. On 48-month follow-up, 12 aneurysms had not changed in size, 4 had grown, 16 had shrunk, and 5 had resolved completely. We describe these 5 patients in detail. The 5 patients were all men, mean age 68 years; their mean aneurysmal sac diameter was 54 mm. The only common finding in all of them was patency of lumbar and inferior mesenteric arteries at pre-procedure evaluation as well as at follow-up. Mean time to complete resolution was 18 months. No major complications were encountered. AAA may resolve completely after endovascular stent-graft implantation. Patent side branches may perhaps contribute to AAA disappearance by antegrade flow. A larger patient population should be reviewed, however, before any statistical conclusion can be drawn.

  14. The impact of endovascular repair of ruptured abdominal aortic aneurysm on the gastrointestinal and renal function.

    PubMed

    Makar, R R; Badger, S A; O'Donnell, M E; Soong, C V; Lau, L L; Young, I S; Hannon, R J; Lee, B

    2014-01-01

    Introduction. Systemic effects of ruptured abdominal aortic aneurysm (rAAA) may be altered by the mode of surgery. This study aimed to determine systemic effects of endovascular aneurysm repair (EVAR) compared to open repair (OR). Patients and Methods. Consecutive patients with rAAA were repaired by OR or EVAR according to computerised tomographic (CT) findings. Renal function was monitored by estimated glomerular filtration rate (eGFR), serum urea and creatinine, and urinary albumin creatinine ratio (ACR). Hepatic function was assessed postoperatively for 5 days. Intestinal function was determined by the paracetamol absorption test. Intestinal permeability was assessed by urinary lactulose/mannitol ratio. Results. 30 rAAA patients were included. Fourteen had eEVAR and sixteen eOR. Serum urea were higher in eOR, while creatinine was similar between groups. Hepatic function showed no intergroup difference. Paracetamol absorption was increased in eEVAR group at day 3 compared to day 1 (P = 0.03), with no similar result in eOR (P = 0.24). Peak lactulose/mannitol ratio was higher in eOR (P = 0.03), with higher urinary L/M ratio in eOR at day 3 (P = 0.02). Clinical intestinal function returned quicker in eEVAR (P = 0.02). Conclusion. EVAR attenuated the organ dysfunction compared to open repair. However, a larger comparative trial would be required to validate this. The clinical trial is registered with reference number EUDRACT: 2013-003373-12.

  15. Effect of Bortezomib on Angiotensin Ⅱ-induced Abdominal Aortic Aneurysm in ApoE(-/-) Mice.

    PubMed

    Li, Fangda; Li, Huihua; Tian, Cui; Nie, Hao; Zheng, Yuehong

    2017-02-20

    Objective To investigate the role of proteasome inhibitor bortezomib (BTZ) in inflammatory response in abdominal aortic aneurysm (AAA) formation induced by angiotensin Ⅱ (Ang Ⅱ). Methods Ang Ⅱ-induced ApoE(-/-) mice AAA models were established. Forty male ApoE(-/-) mice (8-10-week-old) were randomly and equally divided into four groups:Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group.HE staining,immunohistochemical staining,and flow cytometry were used to analyze the inflammatory response. Real-time quantitative polymerase chain reaction (qPCR) was used to analyze the mRNA expression of intercellular cell adhesion molecule-1 (ICAM-1). Western blotting was used to analyze the activation of nuclear factor κB signaling (NF-κB). Results The mean maximum suprarenal aortic diameter (Dmax) of Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group were (1.00±0.01),(0.99±0.01),(1.50±0.13),and (1.20±0.04)mm,respectively (F=8.959,P=0.000). The Dmax of Ang Ⅱ group was significantly larger than those of Sham group (P=0.000) and Ang Ⅱ+BTZ group (P=0.015). The incidence of AAA in Ang Ⅱ group,Ang Ⅱ+BTZ group,and Sham group were 60%,17%,and 0,respectively. HE staining revealed that the abdominal aortic wall thickening was more severe in Ang Ⅱ group than in Sham group and Ang Ⅱ+BTZ group,similar with the infiltration of inflammatory cells. Immunohistochemical staining demonstrated that the CD3(+)T lymphocyte count was significantly higher in Ang Ⅱ group than in Sham group (107.9±15.9 vs. 0,P=0.000) and Ang Ⅱ+BTZ group (107.9±15.9 vs. 0.8±0.5,P=0.000). Flow cytometry also demonstrated that the proportion of the CD3(+)T lymphocytes of the Ang Ⅱ group [(13.50±0.69)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(10.40±0.78)%] at week 1 (t=3.009,P=0.040),and the proportion of the CD3(+)T lymphocytes of the Ang Ⅱ group [(22.70±0.93)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(15.10±0.97)%] at week 4 (t=5

  16. On growth measurements of abdominal aortic aneurysms using maximally inscribed spheres

    PubMed Central

    Gharahi, H.; Zambrano, B. A.; Lim, C.; Choi, J.; Lee, W.; Baek, S.

    2015-01-01

    The maximum diameter, total volume of the abdominal aorta, and its growth rate are usually regarded as key factors for making a decision on the therapeutic operation time for an abdominal aortic aneurysm (AAA) patient. There is, however, a debate on what is the best standard method to measure the diameter. Currently, two dominant methods for measuring the maximum diameter are used. One is measured on the planes perpendicular to the aneurism's central line (orthogonal diameter) and the other one is measured on the axial planes (axial diameter). In this paper, another method called ‘inscribed-spherical diameter’ is proposed to measure the diameter. The main idea is to find the diameter of the largest sphere that fits within the aorta. An algorithm is employed to establish a centerline for the AAA geometries obtained from a set of longitudinal scans obtained from South Korea. This centerline, besides being the base of the inscribed spherical method, is used for the determination of orthogonal and axial diameter. The growth rate parameters are calculated in different diameters and the total volume and the correlations between them are studied. Furthermore, an exponential growth pattern is sought for the maximum diameters over time to examine a nonlinear growth pattern of AAA expansion both globally and locally. The results present the similarities and discrepancies of these three methods. We report the shortcomings and the advantages of each method and its performance in the quantification of expansion rates. While the orthogonal diameter measurement has an ability of capturing a realistic diameter, it fluctuated. On the other hand, the inscribed sphere diameter method tends to underestimate the diameter measurement but the growth rate can be bounded in a narrow region for aiding prediction capability. Moreover, expansion rate parameters derived from this measurement exhibit good correlation with each other and with growth rate of volume. In conclusion, although

  17. From tissue iron retention to low systemic haemoglobin levels, new pathophysiological biomarkers of human abdominal aortic aneurysm.

    PubMed

    Martinez-Pinna, R; Lindholt, J S; Madrigal-Matute, J; Blanco-Colio, L M; Esteban-Salan, M; Torres-Fonseca, M M; Lefebvre, T; Delbosc, S; Laustsen, J; Driss, F; Vega de Ceniga, M; Gouya, L; Weiss, G; Egido, J; Meilhac, O; Michel, J-B; Martin-Ventura, J

    2014-07-03

    Iron deposits are observed in tissue of abdominal aortic aneurysm (AAA) patients, although the underlying mechanisms are not completely elucidated. Therefore we explored circulating markers of iron metabolism in AAA patients, and tested if they could serve as biomarkers of AAA. Increased red blood cell (RBC)-borne iron retention and transferrin, transferrin receptor and ferritin expression was observed in AAA tissue compared to control aorta (immunohistochemistry and western blot). In contrast, decreased circulating iron, transferrin, mean corpuscular haemoglobin concentration (MCHC) and haemoglobin concentration, along with circulating RBC count, were observed in AAA patients (aortic diameter >3 cm, n=114) compared to controls (aortic diameter <3 cm, n=88) (ELISA), whereas hepcidin concentrations were increased in AAA subjects (MS/MS assay). Moreover, iron, transferrin and haemoglobin levels were negatively, and hepcidin positively, correlated with aortic diameter in AAA patients. The association of low haemoglobin with AAA presence or aortic diameter was independent of specific risk factors. Moreover, MCHC negatively correlated with thrombus area in another cohort of AAA patients (aortic diameter 3-5 cm, n=357). We found that anaemia was significantly more prevalent in AAA patients (aortic diameter >5 cm, n=8,912) compared to those in patients with atherosclerotic aorto-iliac occlusive disease (n=17,737) [adjusted odds ratio=1.77 (95% confidence interval: 1.61;1.93)]. Finally, the mortality risk among AAA patients with anaemia was increased by almost 30% [adjusted hazard ratio: 1.29 (95% confidence interval: 1.16;1.44)] as compared to AAA subjects without anaemia. In conclusion, local iron retention and altered iron recycling associated to high hepcidin and low transferrin systemic concentrations could lead to reduced circulating haemoglobin levels in AAA patients. Low haemoglobin levels are independently associated to AAA presence and clinical outcome.

  18. Infection of endovascular abdominal aortic aneurysm stent graft after urosepsis: case report and review of the literature.

    PubMed

    Veger, H T C; Hedeman Joosten, P Ph; Thoma, S R; Visser, M J T

    2013-02-01

    Infection of endovascular abdominal aneurysm stent grafts is an uncommon but known complication. Inoculation with bacteria of the endovascular abdominal aneurysm stent graft during the actual implantation, in the periprocedural hospitalization or later due to an aortoenteric fistula, has been described in the literature. We report a case of endovascular abdominal aortic aneurysm stent graft infection occurring 40 months after implantation in a patient doing well up to an episode of urosepsis. In conclusion, we postulate that poor intraluminal healing of stent grafts, as observed in several explant studies, may result in a higher susceptibility to episodes of bacteremia than prosthetic vascular grafts inserted during open repair. We therefore consider the administration of prophylactic antibiotics in patients with endovascular stent grafts during periods with a likelihood of bacteremia.

  19. Long-term effect of cinacalcet hydrochloride on abdominal aortic calcification in patients on hemodialysis with secondary hyperparathyroidism

    PubMed Central

    Nakayama, Kazunori; Nakao, Kazushi; Takatori, Yuji; Inoue, Junko; Kojo, Shoichirou; Akagi, Shigeru; Fukushima, Masaki; Wada, Jun; Makino, Hirofumi

    2014-01-01

    Background Secondary hyperparathyroidism (SHPT) is one of the common complications in dialysis patients, and is associated with increased risk of vascular calcification. The effects of cinacalcet hydrochloride treatment on bone and mineral metabolism have been previously reported, but the benefit of cinacalcet on vascular calcification remains uncertain. The aim of this study was to evaluate the impact of cinacalcet on abdominal aortic calcification in dialysis patients. Subjects and methods Patients were on maintenance hemodialysis with insufficiently controlled SHPT (intact parathyroid hormone [PTH] >180 pg/mL) by conventional therapies. All subjects were initially administered 25 mg cinacalcet daily, with concomitant use of calcitriol analogs. Abdominal aortic calcification was annually evaluated by calculating aortic calcification area index (ACAI) using multidetector computed tomography (MDCT), from 12 months before to 36 months after the initiation of cinacalcet therapy. Results Twenty-three patients were analyzed in this study. The mean age was 59.0±8.7 years, 34.8% were women, and the mean dialysis duration was 163.0±76.0 months. After administration of cinacalcet, serum levels of intact PTH, phosphorus, and calcium significantly decreased, and mean Ca × P values significantly decreased from 67.4±7.9 mg2/dL2 to 52±7.7 mg2/dL2. Although the ACAI value did not decrease during the observation period, the increase in ACAI between 24 months and 36 months after cinacalcet administration was significantly suppressed. Conclusion Long-term administration of cinacalcet was associated with reduced progression of abdominal aortic calcification, and achieving appropriate calcium and phosphorus levels may reduce the rates of cardiovascular events and mortality in patients on hemodialysis. PMID:24379691

  20. Comparison of the strain field of abdominal aortic aneurysm measured by magnetic resonance imaging and stereovision: a feasibility study for prediction of the risk of rupture of aortic abdominal aneurysm.

    PubMed

    Wang, Yufei; Joannic, David; Delassus, Patrick; Lalande, Alain; Juillion, Patrick; Fontaine, Jean-François

    2015-04-13

    The prediction of the risk of rupture of abdominal aortic aneurysm (AAA) is a complex problem. Currently the criteria to predict rupture of abdominal aortic aneurysms are aneurysm diameter and growth rates. It is generally believed that study of the wall strain distribution could be helpful to find a better decision criterion for surgery of aortic aneurysms before their rupture. The wall strain distribution depends on many biological and biomechanical factors such as elastic properties of the aorta, turbulent blood flow, anatomy of the aorta, presence of thrombus or not and so on. Recently, numerical simulations to estimate rupture-potential have received many attentions. However, none of the medical imaging tools for screening and monitoring of AAAs were studied in terms of mechanical behavior and experimentally to demonstrate their capability to measure relevant variables. The aim of this study was to develop a metrological approach for deployment testing of the ability of techniques for measuring local in-vitro deformations based on comparison of stereovision and MRI. In this paper, we present the implementation approach and results of the study based on cylindrical phantoms with or without AAA representing, respectively, healthy and unhealthy artery. Through this study, an experimental device was developed for the behavior study of AAA during a cardiac cycle. The results show that the stereovision techniques used in laboratory is well suited and is qualitatively and quantitatively equivalent with MRI measurements.

  1. Prevalence and Trends of the Abdominal Aortic Aneurysms Epidemic in General Population - A Meta-Analysis

    PubMed Central

    Li, Xi; Zhao, Ge; Zhang, Jian; Duan, Zhiquan; Xin, Shijie

    2013-01-01

    Objective To conduct a meta-analysis assessing the prevalence and trends of the abdominal aortic aneurysms (AAA) epidemic in general population. Method Studies that reported prevalence rates of AAA from the general population were identified through MEDLINE, EMBASE, Web of Science, and reference lists for the period between 1988 and 2013. Studies were included if they reported prevalence rates of AAA in general population from the community. In stratified analyses possible sources of bias, including areas difference, age, gender and diameter of aneurysms were examined. Publication bias was assessed with Egger's test method. Results 56 studies were identified. The overall pooled prevalence of AAA was 4.8% (4.3%, 5.3%). Stratified analyses showed the following results, areas difference: America 2.2% (2.2%, 2.2%), Europe 2.5% (2.4%, 2.5%), Australia 6.7% (6.5%, 7.0%), Asia 0.5% (0.3%, 0.7%); gender difference: male 6.0% (5.3%, 6.7%), female 1.6% (1.2%, 1.9%); age difference: 55–64years 1.3% (1.2%, 1.5%), 65–74 years 2.8% (2.7%, 2.9%), 75–84 years1.2%(1.1%, 1.3%), ≥85years0.6% (0.4%, 0.7%); aortic diameters difference: 30–39 mm, 3.3% (2.8%, 3.9%), 40–49 mm,0.7% (0.4%,1.0%), ≥50 mm, 0.4% (0.3%, 0.5%). The prevalence of AAA has decreased in Europe from 1988 to 2013. Hypertension, smoking, coronary artery disease, dyslipidemia, respiratory disease, cerebrovascular disease, claudication and renal insufficiency were risk factors for AAA in Europe. Conclusion AAA is common in general population. The prevalence of AAA is higher in Australia than America and Europe. The pooled prevalence in western countries is higher than the Asia. Future research requires a larger database on the epidemiology of AAA in general population. PMID:24312543

  2. Analysis of multiple genetic polymorphisms in aggressive- and slow-growing abdominal aortic aneurysms

    PubMed Central

    Duellman, Tyler; Warren, Christopher L.; Matsumura, Jon; Yang, Jay

    2014-01-01

    Introduction The natural history of abdominal aortic aneurysm (AAA) suggests that some remain slow in growth rate while many develop a more accelerated growth rate reaching a threshold for intervention. We hypothesized that different mechanisms are responsible for AAA that remain slow-growth and never become actionable versus the aggressive-AAA that require intervention may be reflected by distinct associations with genetic polymorphisms. Methods 168 control and 141 AAA subjects all with ultrasound or CT imaging studies covering about 5 years were identified and the AAA growth rate determined from the serial imaging data. Genetic polymorphisms all previously reported as showing significant correlation with AAA: angiotensin 1 receptor (AT1R) (rs5186), interleukin-10 (IL-10) (rs1800896), methyl-tetrahydrofolate reductase (MTHFR) (rs1801133), low density lipoprotein receptor-related protein 1 (LRP1) (rs1466535), angiotensin converting enzyme (ACE) (rs1799752) and several MMP9 SNPs with functional effects on the expression or function were determined by analysis of the genomic DNA. Results AAA subjects were classified as slow-growth rate- (<3.25 mm /yr; n=81) vs. aggressive-AAA (growth rate >3.25 mm /yr, those presenting with a rupture, or those with maximal aortic diameter >5.5 cm (male) or >5.0 cm (female); n=60) and discriminating confounds between the groups identified by logistic regression. Analyses identified MMP9 p-2502 SNP (P=0.029, OR=0.54 (0.31-0.94)) as a significant confound discriminating between control- vs. slow-growth AAA, MMP-9 D165N (P=0.035) and LRP1 (P=0.034) between control vs. aggressive-AAA, and MTHFR (P=0.048, OR=2.99 (1.01-8.86)), MMP9 p-2502 (P=0.037, OR=2.19 (1.05-4.58), and LRP1 (P=0.046, OR= 4.96 (1.03-23.9)) as the statistically significant confounds distinguishing slow- vs. aggressive-AAA. Conclusion Logistic regression identified different genetic confounds for the slow-growth rate-and aggressive-AAA indicating a potential for different

  3. SEX AND VASCULAR BIOMECHANICS: A HYPOTHESIS FOR THE MECHANISM UNDERLYING DIFFERENCES IN THE PREVALENCE OF ABDOMINAL AORTIC ANEURYSMS IN MEN AND WOMEN.

    PubMed

    Taylor, W Robert; Iffrig, Elizabeth; Veneziani, Alessandro; Oshinski, John N; Smolensky, Alexander

    2016-01-01

    The prevalence of abdominal aortic aneurysms differs greatly between men and women across the spectrum of ages. The reason for this discrepancy is not clear and likely involves several factors including the impact of sex hormones. We hypothesize that the unique spatial localization of abdominal aortic aneurysms is dictated in part by local hemodynamic forces on the vascular wall. Specifically, we propose that oscillatory shear stress is a specific signal to the endothelium that initiates the events ultimately leading to abdominal aortic aneurysm formation. We are proposing that sex-dependent differences in oscillatory shear stress in the infra-renal aorta may explain the observed differences between men and women. Initial observations suggest that, indeed, men and women have different degrees of oscillatory blood flow in the infra-renal abdominal aorta. The challenge is to extend these observations to show a causal relationship between oscillatory flow and aneurysm formation.

  4. Abdominal aortic calcification is not superior over other vascular calcification in predicting mortality in hemodialysis patients: a retrospective observational study

    PubMed Central

    2013-01-01

    Background KDIGO (Kidney Disease: Improving Global Outcomes) guidelines recommend that a lateral abdominal radiograph should be performed to assess vascular calcification (VC) in dialysis patients. However, abdominal aortic calcification is a prevalent finding, and it remains unclear whether other anatomical areas of VC can predict mortality more accurately. Methods A total of 217 maintenance hemodialysis patients were enrolled at the Sichuan Provincial People’s Hospital between July 2010 and March 2011. Radiographs of the abdomen, pelvis and hands were evaluated by a radiologist to evaluate the presence of VC. The correlation between different areas of VC and all-cause or cardiovascular mortality was analyzed using univariate and multivariate models. Results The prevalence of VC was 70.0% (152 patients), and most had abdominal aortic calcification (90.1%). During 26 ± 7 months of follow-up, 37 patients died. The VC score was independently associated with patient mortality. VC observed on abdominal radiographs (abdominal aortic calcification) was associated with all-cause mortality in models adjusted for cardiovascular risk factors (HR, 4.69; 95%CI, 1.60-13.69) and dialysis factors (HR, 3.38; 95%CI, 1.18-9.69). VC in the pelvis or hands was associated with all-cause mortality in the model adjusted for dialysis factors. When three combinations of VC in different radiographs were included in models, the presence of abdominal VC was only significantly associated with all-cause mortality in the integrated model. VC in the abdomen and pelvis was associated with all-cause mortality in the model adjusted for cardiovascular factors and the integrated model, but neither was significantly associated with cardiovascular mortality. VC in all radiographs was significantly associated with a more than 6-fold risk of all-cause mortality and a more than 5-fold risk of cardiovascular mortality compared to patients without VC. Conclusions VC in different arteries as shown on

  5. Zinc Prevents Abdominal Aortic Aneurysm Formation by Induction of A20-Mediated Suppression of NF-κB Pathway

    PubMed Central

    Bai, Shu-Ling; Hou, Wei-Jian; Li, Xiang; Tong, Hao

    2016-01-01

    Chronic inflammation and degradation of elastin are the main processes in the development of abdominal aortic aneurysm (AAA). Recent studies show that zinc has an anti-inflammatory effect. Based on these, zinc may render effective therapy for the treatment of the AAA. Currently, we want to investigate the effects of zinc on AAA progression and its related molecular mechanism. Rat AAA models were induced by periaortic application of CaCl2. AAA rats were treated by daily intraperitoneal injection of ZnSO4 or vehicle alone. The aorta segments were collected at 4 weeks after surgery. The primary rat aortic vascular smooth muscle cells (VSMCs) were stimulated with TNF-α alone or with ZnSO4 for 3 weeks. The results showed that zinc supplementation significantly suppressed the CaCl2-induced expansion of the abdominal aortic diameter, as well as a preservation of medial elastin fibers in the aortas. Zinc supplementation also obviously attenuated infiltration of the macrophages and lymphocytes in the aortas. In addition, zinc reduced MMP-2 and MMP-9 production in the aortas. Most importantly, zinc treatment significantly induced A20 expression, along with inhibition of the NF-κB canonical signaling pathway in vitro in VSMCs and in vivo in rat AAA. This study demonstrated, for the first time, that zinc supplementation could prevent the development of rat experimental AAA by induction of A20-mediated inhibition of the NF-κB canonical signaling pathway. PMID:26918963

  6. Zinc Prevents Abdominal Aortic Aneurysm Formation by Induction of A20-Mediated Suppression of NF-κB Pathway.

    PubMed

    Yan, Ya-Wei; Fan, Jun; Bai, Shu-Ling; Hou, Wei-Jian; Li, Xiang; Tong, Hao

    2016-01-01

    Chronic inflammation and degradation of elastin are the main processes in the development of abdominal aortic aneurysm (AAA). Recent studies show that zinc has an anti-inflammatory effect. Based on these, zinc may render effective therapy for the treatment of the AAA. Currently, we want to investigate the effects of zinc on AAA progression and its related molecular mechanism. Rat AAA models were induced by periaortic application of CaCl2. AAA rats were treated by daily intraperitoneal injection of ZnSO4 or vehicle alone. The aorta segments were collected at 4 weeks after surgery. The primary rat aortic vascular smooth muscle cells (VSMCs) were stimulated with TNF-α alone or with ZnSO4 for 3 weeks. The results showed that zinc supplementation significantly suppressed the CaCl2-induced expansion of the abdominal aortic diameter, as well as a preservation of medial elastin fibers in the aortas. Zinc supplementation also obviously attenuated infiltration of the macrophages and lymphocytes in the aortas. In addition, zinc reduced MMP-2 and MMP-9 production in the aortas. Most importantly, zinc treatment significantly induced A20 expression, along with inhibition of the NF-κB canonical signaling pathway in vitro in VSMCs and in vivo in rat AAA. This study demonstrated, for the first time, that zinc supplementation could prevent the development of rat experimental AAA by induction of A20-mediated inhibition of the NF-κB canonical signaling pathway.

  7. Comparative study of abdominal and thoracic aortic aneurysms: their pathogenesis and a gingival fibroblasts-based ex vivo treatment.

    PubMed

    Cherifi, Hafida; Gogly, Bruno; Loison-Robert, Ludwig-Stanislas; Couty, Ludovic; Ferré, François Côme; Nassif, Ali; Lafont, Antoine; Fournier, Benjamin Pj

    2015-01-01

    Aortic aneurysms (AAs) consist of slow proteolysis and loss of both collagen and elastin matrix in the aorta wall, leading to wall dilation, weakening and rupture in well-advanced lesions. This can occur in both abdominal aorta (Abdominal Aortic Aneurysm: AAA) and thoracic aorta (Thoracic Aortic Aneurysm: TAA). To date, no non-surgical therapy has been proposed to slow or stop AA progression. Previously published preclinical studies from our team using an aneurysm rabbit model showed a promising concept for treatment of AAs with gingival fibroblast (GFs) which are readily available cells. In this study, we investigated the possible tissue repair of human AAAs and TAAs using ex vivo models co-cultured with GFs. Histological analysis showed that TAA and AAA are two distinct pathologies. Both lesions presented destruction of the aorta wall, highly evidenced in AAA samples. The results have confirmed the presence of the bacterial Porphyromonas gingivalis (Pg) protein in all AAA samples, but not in TAA samples, indicating the possible role of an infectious factor in the developing and progression of AAA lesions compared to TAA. The co-culture of GFs with AA lesions shows increased expression of TIMP-1, the inhibitor of the aneurysm severity marker MMP-9. Our study indicates that GFs might ameliorate aorta wall reestablishment in both AA types by their regenerative and immunomodulatory capacities. It also demonstrates the possible infectious cause of AAA compared with TAA that may explain their different behavior.

  8. Perfusion computed tomography imaging of abdominal aortic aneurysms may be of value for patient specific rupture risk estimation.

    PubMed

    Kontopodis, Nikolaos; Galanakis, Nikolaos; Tsetis, Dimitrios; Ioannou, Christos V

    2017-04-01

    Abdominal aortic aneurysm (AAA) continues to pose a significant cause of unexpected mortality in the developed countries with its incidence constantly rising. The indication of elective surgical repair is currently based on the maximum diameter and growth rate criteria which represent an oversimplification of the Law of Laplace stating that the stress exerted in a cylinder or sphere is proportional to its radius. These criteria fail to capture the complex pathophysiology of the aneurismal disease thus often leading to therapeutic inaccuracies (treating large AAAs with a very low actual rupture risk while observing smaller ones with a much greater risk). Aneurysmal disease is mainly a degenerative process leading to loss of structural integrity of the diseased aortic wall which cannot withhold the stresses due to systemic pressurization. Moreover aortic wall degeneration has been shown to be a localized phenomenon and rupture depends on the pointwise comparison of strength and stress rather than a global aortic wall weakening. Ex-vivo mechanical studies have related vessel wall hypoxia to loss of structural endurance and reduced wall strength. Therefore a module to capture in vivo variation of aortic wall blood supply and oxygenation would be of value for the evaluation of AAA rupture risk. Perfusion computed tomography (PCT) imaging represents a novel technique which has been already used to estimate tissue vascularity in several clinical conditions but not aneurismal disease. We hypothesize that PCT could be used as an adjunct tool during AAA diagnostics in order to evaluate aortic wall oxygenation in vivo, therefore providing a possible means to identify weak spots making the lesion amenable to rupture.

  9. TGF-β Neutralization Enhances AngII-Induced Aortic Rupture and Aneurysm in Both Thoracic and Abdominal Regions

    PubMed Central

    Howatt, Deborah A.; Balakrishnan, Anju; Moorleghen, Jessica J.; Cassis, Lisa A.; Daugherty, Alan

    2016-01-01

    AngII and TGF-β interact in development of thoracic and abdominal aortic diseases, although there are many facets of this interaction that have not been clearly defined. The aim of the present study was to determine the effects of TGF-β neutralization on AngII induced-aortic pathologies. Male C57BL/6J mice were administered with either a rabbit or mouse TGF-β neutralizing antibody and then infused with AngII. The rabbit TGF-β antibody modestly reduced serum TGF-β concentrations, with no significant enhancements to AngII-induced aneurysm or rupture. Administration of this rabbit TGF-β antibody in mice led to high serum titers against rabbit IgG that may have attenuated the neutralization. In contrast, a mouse TGF-β antibody (1D11) significantly increased rupture in both the ascending and suprarenal aortic regions, but only at doses that markedly decreased serum TGF-β concentrations. High doses of 1D11 antibody significantly increased AngII-induced ascending and suprarenal aortic dilatation. To determine whether TGF-β neutralization had effects in mice previously infused with AngII, the 1D11 antibody was injected into mice that had been infused with AngII for 28 days and were observed during continued infusion for a further 28 days. Despite near ablations of serum TGF-β concentrations, the mouse TGF-β antibody had no effect on aortic rupture or dimensions in either ascending or suprarenal region. These data provide further evidence that AngII-induced aortic rupture is enhanced greatly by TGF-β neutralization when initiated before pathogenesis. PMID:27104863

  10. Fluid-structure interaction in abdominal aortic aneurysms: effects of asymmetry and wall thickness

    PubMed Central

    Scotti, Christine M; Shkolnik, Alexander D; Muluk, Satish C; Finol, Ender A

    2005-01-01

    Background Abdominal aortic aneurysm (AAA) is a prevalent disease which is of significant concern because of the morbidity associated with the continuing expansion of the abdominal aorta and its ultimate rupture. The transient interaction between blood flow and the wall contributes to wall stress which, if it exceeds the failure strength of the dilated arterial wall, will lead to aneurysm rupture. Utilizing a computational approach, the biomechanical environment of virtual AAAs can be evaluated to study the affects of asymmetry and wall thickness on this stress, two parameters that contribute to increased risk of aneurysm rupture. Methods Ten virtual aneurysm models were created with five different asymmetry parameters ranging from β = 0.2 to 1.0 and either a uniform or variable wall thickness to study the flow and wall dynamics by means of fully coupled fluid-structure interaction (FSI) analyses. The AAA wall was designed to have a (i) uniform 1.5 mm thickness or (ii) variable thickness ranging from 0.5 – 1.5 mm extruded normally from the boundary surface of the lumen. These models were meshed with linear hexahedral elements, imported into a commercial finite element code and analyzed under transient flow conditions. The method proposed was then compared with traditional computational solid stress techniques on the basis of peak wall stress predictions and cost of computational effort. Results The results provide quantitative predictions of flow patterns and wall mechanics as well as the effects of aneurysm asymmetry and wall thickness heterogeneity on the estimation of peak wall stress. These parameters affect the magnitude and distribution of Von Mises stresses; varying wall thickness increases the maximum Von Mises stress by 4 times its uniform thickness counterpart. A pre-peak systole retrograde flow was observed in the AAA sac for all models, which is due to the elastic energy stored in the compliant arterial wall and the expansion force of the artery

  11. Exendin-4 therapy still offered an additional benefit on reducing transverse aortic constriction-induced cardiac hypertrophy-caused myocardial damage in DPP-4 deficient rats

    PubMed Central

    Lu, Hung-I; Chung, Sheng-Ying; Chen, Yi-Ling; Huang, Tein-Hung; Zhen, Yen-Yi; Liu, Chu-Feng; Chang, Meng-Wei; Chen, Yung-Lung; Sheu, Jiunn-Jye; Chua, Sarah; Yip, Hon-Kan; Lee, Fan-Yen

    2016-01-01

    Inhibition of dipeptidyl peptidase-IV (DPP-4) enzyme activity has been revealed to protect myocardium from ischemia-reperfusion through enhancing the endogenous glucagon-like peptide-1 (GLP-1) level. However, whether exogenous supply of exendin-4, an analogue of GLP-1, would still offer benefit for protecting myocardial damage from trans-aortic constriction (TAC)-induced hypertrophic cardiomyopathy in preexistence of DPP-4 deficiency (DPP-4D) remained unclear. Male-adult (DPP-4D) rats (n = 32) were randomized into group 1 [sham control (SC)], group 2 (DPP-4D + TAC), group 3 [DPP-4D + TAC + exendin-4 10 µg/day], and group 4 [DPP-4D + TAC + exendin-4 10 µg + exendin-9-39 10 µg/day]. The rats were sacrificed by day 60 after last echocardiographic examination. By day 60 after TAC, left ventricular ejection fraction (LVEF) (%) was highest in group 1 and lowest in group 2, and significantly lower in group 4 than that in group 3 (all p < 0.001). The protein expressions of oxidative stress (oxidized protein, NOX-1, NOX-2), inflammatory (MMP-9, TNF-α, NF-κB), apoptotic (Bax, cleaved caspase 3 and PARP), fibrotic (TGF-β, Smad3), heart failure (BNP, β-MHC), DNA damaged (γ-H2AX) and ischemic stress (p-P38, p-Akt, p53, ATM) biomarkers showed an opposite pattern of LVEF among the four groups (all p < 0.03). Fibrotic area (by Masson’s trichrome, Sirius red), and cellular expressions of DNA-damaged markers (Ki-67+, γ-H2AX+, CD90+/53BP1+) displayed an identical pattern, whereas cellular expressions of angiogenesis (CD31+, α-SMA+) and sarcomere length exhibited an opposite pattern compared to that of oxidative stress among the four groups (all p < 0.001). Take altogether, Exendin-4 effectively suppressed TAC-induced pathological cardiac hypertrophy in DPP-4D rat. PMID:27158369

  12. Associations of Diabetes and Obesity with Risk of Abdominal Aortic Aneurysm in Men

    PubMed Central

    Djousse, Luc; Song, Yiqing; Akinkuolie, Akintunde O.; Matsumoto, Chisa; Manson, JoAnn E.; Gaziano, J. Michael; Sesso, Howard D.

    2017-01-01

    Background. The associations of diabetes and obesity with the risk of abdominal aortic aneurysm (AAA) are inconclusive in previous studies. Subjects/Methods. We conducted prospective analysis in the Physicians' Health Study. Among 25,554 male physicians aged ≥ 50 years who reported no AAA at baseline, 471 reported a newly diagnosed AAA during a mean of 10.4 years' follow-up. Results. Compared with men who had baseline body mass index (BMI) < 25 kg/m2, the multivariable hazard ratio (HR [95% CI]) of newly diagnosed AAA was 1.30 [1.06–1.59] for BMI 25–<30 kg/m2 and 1.69 [1.24–2.30] for BMI ≥ 30 kg/m2. The risk of diagnosed AAA was significantly higher by 6% with each unit increase in baseline BMI. This association was consistent regardless of the other known AAA risk factors and preexisting vascular diseases. Overall, baseline history of diabetes tended to be associated with a lower risk of diagnosed AAA (HR = 0.79 [0.57–1.11]); this association appeared to vary by follow-up time (HR = 1.56 and 0.63 during ≤ and >2 years' follow-up, resp.). Conclusion. In a large cohort of middle-aged and older men, obesity was associated with a higher risk, while history of diabetes tended to associate with a lower risk of diagnosed AAA, particularly over longer follow-up. PMID:28326193

  13. Computational Growth and Remodeling of Abdominal Aortic Aneurysms Constrained by the Spine

    PubMed Central

    Farsad, Mehdi; Zeinali-Davarani, Shahrokh; Choi, Jongeun; Baek, Seungik

    2015-01-01

    Abdominal aortic aneurysms (AAAs) evolve over time, and the vertebral column, which acts as an external barrier, affects their biomechanical properties. Mechanical interaction between AAAs and the spine is believed to alter the geometry, wall stress distribution, and blood flow, although the degree of this interaction may depend on AAAs specific configurations. In this study, we use a growth and remodeling (G&R) model, which is able to trace alterations of the geometry, thus allowing us to computationally investigate the effect of the spine for progression of the AAA. Medical image-based geometry of an aorta is constructed along with the spine surface, which is incorporated into the computational model as a cloud of points. The G&R simulation is initiated by local elastin degradation with different spatial distributions. The AAA–spine interaction is accounted for using a penalty method when the AAA surface meets the spine surface. The simulation results show that, while the radial growth of the AAA wall is prevented on the posterior side due to the spine acting as a constraint, the AAA expands faster on the anterior side, leading to higher curvature and asymmetry in the AAA configuration compared to the simulation excluding the spine. Accordingly, the AAA wall stress increases on the lateral, posterolateral, and the shoulder regions of the anterior side due to the AAA–spine contact. In addition, more collagen is deposited on the regions with a maximum diameter. We show that an image-based computational G&R model not only enhances the prediction of the geometry, wall stress, and strength distributions of AAAs but also provides a framework to account for the interactions between an enlarging AAA and the spine for a better rupture potential assessment and management of AAA patients. PMID:26158885

  14. Exercise adherence in the elderly: Experience with abdominal aortic aneurysm simple treatment and prevention.

    PubMed

    McElrath, Mary; Myers, Jonathan; Chan, Khin; Fonda, Holly

    2017-03-01

    Poor adherence to health-related behaviors can have serious health consequences. Cardiac rehabilitation has been documented to have physiological and psychosocial benefits; however, optimizing adherence to exercise in patients with cardiovascular disease is a particular challenge. We recently completed a large, 6-year randomized trial of exercise training in elderly patients with abdominal aortic aneurysm (AAA) disease (50-85 years), which provided an opportunity to describe adherence strategies in this unique group of elderly individuals. Patients were randomized to exercise therapy or usual care. Using a case-management approach, a combination of center and home-based training was used during which patients trained for up to 3 years. We observed that overall, 84% of subjects in the exercise group completed ≥1 year in the study, achieving a mean energy expenditure of 1,999 ± 1,030 kcals per week. Subjects in the exercise group were more likely to drop out of the study as compared with usual care, though none of the reasons for dropping out were associated with exercise participation (eg, exercise-related injury). Reasons for withdrawal included orthopedic problems, lost physician coverage, time constraints, and AAA repair. Although the groups were matched for AAA size at baseline, there was a trend for more AAA repairs among usual care subjects versus those in the exercise group (12 [17.6%] vs 5 [6.9%], P = 0.09). The case-managed approach to optimizing adherence used was reasonably successful in achieving a training response (ie, improvement in exercise capacity) in elderly patients with AAA, a group for whom little is previously known regarding the effects of rehabilitation.

  15. Quantification of the migration and deformation of abdominal aortic aneurysm stent grafts

    NASA Astrophysics Data System (ADS)

    Mattes, Julian; Steingruber, Iris; Netzer, Michael; Fritscher, Karl; Kopf, Helmut; Jaschke, Werner; Schubert, Rainer

    2006-03-01

    The endovascular repair of an abdominal aortic aneurysm is a minimal invasive therapy which has been established during the past 15 years. A stent-graft is placed inside the aorta in order to cover the weakened regions of its wall. During a time interval of one or more years the stent-graft can migrate and deform with the risk of the occlusion of one of its limbs or of the rupture of the aneurysm. In this work we developed several strategies to quantify the migration and deformation in order to assess the risk coming with these movements and especially to characterize appearing complications by them. We calculated the rigid movement of the stent-graft and the aorta relative to the spinal canal. For this purpose, firstly, we rigidly registered the spinal canals, extracted for the different points in time, in order to establish a fixed reference system. All objects have been segmented first and surface points have been determined before applying a rigid and non-rigid point set registration algorithm. The change in the residual error after registration of the stent-graft with an increasing number of degrees of freedom indicates the amount of change in the stent-graft's morphology. We investigated a sample of 9. Two cases could be clearly distinguished by the quantified parameters: a high global migration and a strong reduction of the residual error after non-rigid registration. In both cases, strong complications have been detected by the examination of clinical experts but only by means of the images acquired one year later.

  16. Reporting individual surgeon outcomes does not lead to risk aversion in abdominal aortic aneurysm surgery.

    PubMed

    Saratzis, A; Thatcher, A; Bath, M F; Sidloff, D A; Bown, M J; Shakespeare, J; Sayers, R D; Imray, C

    2017-02-01

    INTRODUCTION Reporting surgeons' outcomes has recently been introduced in the UK. This has the potential to result in surgeons becoming risk averse. The aim of this study was to investigate whether reporting outcomes for abdominal aortic aneurysm (AAA) surgery impacts on the number and risk profile (level of fitness) of patients offered elective treatment. METHODS Publically available National Vascular Registry data were used to compare the number of AAAs treated in those centres across the UK that reported outcomes for the periods 2008-2012, 2009-2013 and 2010-2014. Furthermore, the number and characteristics of patients referred for consideration of elective AAA repair at a single tertiary unit were analysed yearly between 2010 and 2014. Clinic, casualty and theatre event codes were searched to obtain all AAAs treated. The results of cardiopulmonary exercise testing (CPET) were assessed. RESULTS For the 85 centres that reported outcomes in all three five-year periods, the median number of AAAs treated per unit increased between the periods 2008-2012 and 2010-2014 from 192 to 214 per year (p=0.006). In the single centre cohort study, the proportion of patients offered elective AAA repair increased from 74% in 2009-2010 to 81% in 2013-2014, with a maximum of 84% in 2012-2013. The age, aneurysm size and CPET results (anaerobic threshold levels) for those eventually offered elective treatment did not differ significantly between 2010 and 2014. CONCLUSIONS The results do not support the assumption that reporting individual surgeon outcomes is associated with a risk averse strategy regarding patient selection in aneurysm surgery at present.

  17. Association of abdominal aortic calcium with coronary artery calcium and obstructive coronary artery disease: a pilot study.

    PubMed

    Zweig, Bryan M; Sheth, Meetkumar; Simpson, Steve; Al-Mallah, Mouaz H

    2012-02-01

    This study sought to determine the association of abdominal aortic calcium (AAC) with coronary artery calcium (CAC) and obstructive coronary artery disease (CAD). We included 58 patients (mean age 54.4 years, 40% males) without known CAD who underwent a non-contrast abdominal computed tomography (CT) scan and 64-slice coronary computed tomography angiography (CCTA) within 2 years. A total AAC score using Agatston method was calculated in the abdominal aorta from the takeoff of the celiac artery to the aortic bifurcation. A total of 43/58 patients had AAC. Patients with AAC were older with no differences in other baseline characteristics. None of the patients with a zero AAC score had obstructive CAD. Thus, an AAC score of zero had a 100% negative predictive value (NPV) and 23% positive predictive value (PPV) for the detection of obstructive CAD and an 80% NPV and 79% PPV for detection of any coronary plaque. Using multivariate linear regression, AAC score was an independent predictor of CAC score after adjusting for age (P < 0.001). In our analysis, AAC score correlates with CAC score and has a high NPV to rule out CAD. The absence of AAC may help exclude obstructive coronary disease and improve the selection of patients that may benefit from further risk stratification.

  18. [Use of an iliac branched endoprostheis in endovascular treatment for an abdominal aortic aneurysm combined with aneurysms of both common iliac arteries].

    PubMed

    Imaev, T E; Kuchin, I V; Lepilin, P M; Kolegaev, A S; Medvedeva, I S; Komlev, A E; Akchurin, R S

    An abdominal aortic aneurysm appears to be combined with aneurysmatic lesions of the common iliac arteries in 30-40% of cases. Like abdominal aortic aneurysms, aneurysms of the common iliac arteries rarely manifest themselves clinically. The lethality rate in case of rupture is comparable to that for rupture of an abdominal aortic aneurysm. During endoprosthetic repair of abdominal aortic aneurysms combined with aneurysms of the common iliac arteries, in order to prevent endoleaks and to improve the distal zone of fixation of endografts surgeons often resort to embolization of internal iliac arteries, which may lead to ischaemic postoperative complications. One of the methods of preserving pelvic blood flow is the use of an iliac branched endograft. A series of studies evaluating long-term outcomes demonstrated that this method proved to be both safe and effective, and with the suitable anatomy is a method of choice in high surgical risk patients. The present article deals with a clinical case report concerning bilateral endoprosthetic repair of the common iliac arteries, combined with endoprosthetic repair of an abdominal aortic aneurysm, with the description of technical peculiarities of implanting an iliac branched graft.

  19. Hemodynamic responses to acute aortic coarctation in conscious sinoaortic denervated rats.

    PubMed

    Fazan Júnior, R; Machado, B H; Salgado, H C

    1997-10-01

    The hemodynamic responses to acute (45 min) partial aortic constriction were studied in conscious intact (N = 7) or sinoaortic denervated (SAD) adult male Wistar rats (280-350 g, N = 7) implanted with carotid and femoral arterial catheters, a pneumatic cuff around the abdominal aorta and a pulsed Doppler flow probe to measure changes in aortic resistance. In addition, the hypertensive response and the reflex bradycardia elicited by total (N = 8) vs partial (N = 7) aortic constriction (monitored by maintenance of the pressure distal to the cuff at 50 mmHg) were compared in two other groups of intact rats. Intact rats presented a smaller hypertensive response (26 to 40% above basal level) to partial aortic constriction than SAD rats (38 to 58%). The calculated change in aortic resistance imposed by constriction of the aorta increased progressively only in intact rats, but was significantly smaller (193 to 306%) than that observed (501 to 591%) in SAD rats. Intact rats showed a significant bradycardia (23 to 26% change in basal heart rate) throughout coarctation, whereas the SAD rats did not (1 to 3%). Partial or total occlusion of the aorta induced similar hypertensive responses (37-38% vs 24-30% for total constriction) as well as reflex bradycardia (-15 to -17% vs -22 to -33%) despite a greater gradient in pressure (97-98 vs 129-140 mmHg) caused by total constriction. The present data indicate that the integrity of the baroreflex in intact rats can cause the hypertensive response to level off at a lower value than in SAD rats despite a progressive increase in aortic resistance. In addition, they also indicate that the degree of partial aortic constriction by maintenance of the pressure distal to the cuff at 50 mmHg already elicits a maximal stimulation of the arterial baroreflex.

  20. Increased Expression of Lamin A/C Correlate with Regions of High Wall Stress in Abdominal Aortic Aneurysms

    PubMed Central

    Malkawi, Amir; Pirianov, Grisha; Torsney, Evelyn; Chetter, Ian; Sakalihasan, Natzi; Loftus, Ian M.; Nordon, Ian; Huggins, Christopher; Charolidi, Nicoletta; Thompson, Matt; Xu, Xie Yun; Cockerill, Gillian W.

    2015-01-01

    Background Since aortic diameter is the most ­significant risk factor for rupture, we sought to identify stress-dependent changes in gene expression to illuminate novel molecular processes in aneurysm rupture. Materials and Methods We constructed finite element maps of abdominal computerized tomography scans (CTs) of seven abdominal aortic aneurysm (AAA) patients to map wall stress. Paired biopsies from high- and low-stress areas were collected at surgery using vascular landmarks as coordinates. Differential gene expression was evaluated by Illumina Array analysis, using the whole genome DNA-mediated, annealing, selection, extension, and ligation (DASL) gene chip (n = 3 paired samples). Results The sole significant candidate from this analysis, Lamin A/C, was validated at the protein level, using western blotting. Lamin A/C expression in the inferior mesenteric vein (IMV) of AAA patients was compared to a control group and in aortic smooth muscle cells in culture in response to physiological pulsatile stretch. ­Areas of high wall stress (n = 7) correlate to those ­regions which have the thinnest walls [778 µm (585–1120 µm)] in comparison to areas of lowest wall stress [1620 µm (962–2919 µm)]. Induced expression of Lamin A/C ­correlated with areas of high wall stress from AAAs but was not significantly induced in the IMV from AAA patients compared to controls (n = 16). Stress-induced expression of Lamin A/C was mimicked by exposing aortic smooth muscle cells to prolonged pulsatile stretch. Conclusion Lamin A/C protein is specifically increased in areas of high wall stress in AAA from patients, but is not increased on other vascular beds of aneurysm patients, suggesting that its elevation may be a compensatory response to the pathobiology leading to aneurysms. PMID:27175366

  1. Non-visualized aorta in abdominal aortic aneurysm screening: Screening outcomes and the influence of subject and programme characteristics.

    PubMed

    Bennett, Damien; Stewart, Diane; Kearns, Deirdre; Mairs, Adrian; Ellis, Peter

    2017-01-01

    Objectives To compare abdominal aortic aneurysm screening outcomes of men with non-visualized aorta at original scan with subsequent scans and to determine predictors of non-visualized aorta. Methods In the Northern Ireland Abdominal Aortic Aneurysm screening programme, outcomes (discharge, annual surveillance, three-monthly surveillance, or vascular referral) and patient and programme characteristics (age, deprivation quintile, family history, technician experience, and screening location) for men with non-visualized aorta were investigated at original scan, and first and second rescans. Results Non-visualized aorta proportions were 2.9, 11.4, and 4.7% at original, first, and second rescan, respectively. There were no differences in screening outcomes between scanning stages (98.4, 97.6, and 97.4% <3 cm). There were 42 men (0.13%) with aortas ≥5.5 cm at original scan, but none at first and second rescan. A significantly greater proportion with non-visualized aorta were from more deprived (5.0%) than less deprived areas (1.7%). Deprivation quintile and staff role were significant independent non-visualized aorta predictors at original scan, and staff role at first rescan. Men from less deprived areas were three times as likely to have aortas visualized than those from more deprived areas (OR = 3.0, CI = 2.4-3.8) at original scan. A man scanned by screening technician compared with lead sonographer was 51% less likely to have aorta visualized at original scan and 94% less likely at first rescan. Conclusions The risk of abdominal aortic aneurysm in men with non-visualized aorta on first or subsequent rescans is no more than for those with visualized aorta on original scanning. Men from deprived areas are much more likely to have non-visualized aorta at original scan.

  2. Successful use of talc sclerodesis to control a persistent high-output groin seroma following endovascular abdominal aortic aneurysm repair.

    PubMed

    Metcalfe, David; Sinha, Sidhartha; Sadek, Norah; Ho, Andrew L; Karthikesalingam, Alan; Jones, Keith G; Hinchliffe, Robert J; Thompson, Matt M; Black, Stephen A

    2013-08-01

    Groin wound lymphatic complications after vascular procedures are accompanied by increased risk of infection, prolonged hospital stay, and greater patient morbidity. High-output groin seromas can be difficult to manage and refractory to established interventions. Although subcutaneous talc has been used to prevent seroma accumulation in other high-risk surgical fields, such as after axillary lymph node dissection, it has not been described in the context of vascular surgery. This article presents the first reported case of a persistent high-output groin seroma after endovascular abdominal aortic aneurysm repair managed successfully with intraoperative application of sterile talc.

  3. Progression of perianeurysmal inflammation after endovascular aneurysm repair for inflammatory abdominal aortic and bilateral common iliac artery aneurysms.

    PubMed

    Igari, Kimihiro; Kudo, Toshifumi; Uchiyama, Hidetoshi; Toyofuku, Takahiro; Inoue, Yoshinori

    2015-02-01

    The use of endovascular aneurysm repair (EVAR) to treat inflammatory abdominal aortic aneurysms (IAAAs) has been reported, and this procedure appears to be preferable to open surgical repair because of intraoperative difficulties related to inflammation. We herein report a case of IAAA and bilateral inflammatory common iliac artery aneurysms that was successfully treated with bifurcated stent grafting. The perianeurysmal inflammation worsened postoperatively, requiring the placement of a ureteric stent. EVAR is feasible in cases of inflammatory aneurysms; however, the potential for an inflammatory response should be taken into account when considering the application of EVAR in patients with IAAA.

  4. Successful surgical treatment of primary aorto-duodenal fistula associated with inflammatory abdominal aortic aneurysm: A case report.

    PubMed

    Ikeda, K; Abe, T; Itou, M; Tamiya, Y; Tanaka, T; Kazui, T

    1999-06-01

    We report a rare case of a 50-year-old woman with intermittent gastrointestinal (GI) bleeding and diagnosed as having primary aortoenteric fistula (PAEF) with inflammatory abdominal aortic aneurysm (IAAA). She was transferred to our institution with suspected PAEF as assessed by duodenoscopy and CT scan. As the patient was in shock due to massive GI-bleeding two days after admission, we performed an emergency laparotomy. The fistula was closed and the aneurysm replaced by a Woven Dacron Graft with an inter-positioning omental flap. A high index of suspicion is the most important diagnostic aid to prevent overlooking this often fatal disease.

  5. Chimney-Graft as a Bail-Out Procedure for Endovascular Treatment of an Inflammatory Juxtarenal Abdominal Aortic Aneurysm.

    PubMed

    Fratesi, Francesca; Handa, Ashok; Uberoi, Raman; Sideso, Ediri

    2015-01-01

    Inflammatory and juxtarenal Abdominal Aortic Aneurysm (j-iAAA) represents a technical challenge for open repair (OR) due to the peculiar anatomy, extensive perianeurysmal fibrosis, and dense adhesion to the surrounding tissues. A 68-year-old man with an 11 cm asymptomatic j-iAAA was successfully treated with elective EVAR and chimney-graft (ch-EVAR) without postprocedural complications. Target vessel patency and normal renal function are present at 24-month follow-up. The treatment of j-iAAA can be technically challenging. ch-EVAR is a feasible and safe bail-out method for elective j-iAAA with challenging anatomy.

  6. Endoluminal Treatment of Ruptured Abdominal Aortic Aneurysm with Small Intestinal Submucosa Sandwich Endografts: A Pilot Study in Sheep

    SciTech Connect

    Yamada, Katsuyuki; Pavcnik, Dusan; Uchida, Barry T.; Timmermans, Hans A.; Corless, Christopher L.; Yin, Qiang; Yamakado, Koichiro; Wha Park, Joong; Roesch, Josef; Keller, Frederick S.; Sato, Morio; Yamada, Ryusaku

    2001-03-15

    Purpose: To evaluate efficacy of small intestinal submucosa (SIS) Sandwich endografts for the treatment of acute rupture of abdominal aortic aneurysms (AAA) and to explore the short-term reaction of the aorta to this material.Methods: In eight adult sheep, an infrarenal AAA was created transluminally by dilation of a short Palmaz stent. In six sheep, the aneurysm was then ruptured by overdilation of the stent with a large angioplasty balloon. Two sheep with AAAs that were not ruptured served as controls. A SIS Sandwich endograft, consisting of a Z stent frame with 5 bodies and covered inside and out with SIS, was used to exclude the ruptured and non-ruptured AAAs. Follow-up aortography was done immediately after the procedure and before sacrifice at 4, 8, or 12 weeks. Autopsy and histologic studies followed.Results: Endograft placement was successful in all eight sheep. Both ruptured and non-ruptured AAAs were successfully excluded. Three animals with AAA rupture developed hind leg paralysis due to compromise of the arterial supply to the lower spinal cord and were sacrificed 1 day after the procedure. In five animals, three with rupture and two controls, follow-up aortograms revealed no aortic stenoses and no perigraft leaks. Gross and histologic studies revealed incorporation of the endografts into the aortic wall with replacement of SIS by dense neointima that was completely endothelialized in areas where the endograft was in direct contact with the aortic wall. In central portions of the endograft, in contact with the thrombosed aneurysm, endothelialization was incomplete even at 12 weeks.Conclusion: The SIS Sandwich endografts effectively excluded simple AAAs and ruptured AAAs. They were rapidly incorporated into the aortic wall. A detailed long-term study is warranted.

  7. Transperitoneal repair of a juxtarenal abdominal aortic aneurysm and co-existent horseshoe kidney with division of the renal isthmus

    PubMed Central

    Hajibandeh, Shahin; Hajibandeh, Shahab; Johnpulle, Michelle; Perricone, Vittorio

    2015-01-01

    The co-existence of abdominal aortic aneurysm (AAA) and horseshoe kidney (HSK) is rare. We report a 67-year-old man with an expanding juxtarenal AAA associated with a HSK. The aneurysm had a severely angulated neck and contained a significant amount of mural thrombus. The isthmus of HSK closely lied over the aneurysm, making its exposure extremely difficult. The aneurysm was successfully repaired using transperitoneal approach with division of the renal isthmus and without any need for the renal artery reconstruction. Despite the potential complications, particularly renal insufficiency, associated with division of the renal isthmus and suprarenal cross-clamping of the abdominal aorta, in our case, post-operative period was uneventful and the patient's recovery was satisfactory. PMID:26511935

  8. Endovascular Surgery for Inflammatory Abdominal Aortic Aneurysm with Contrast Allergy—Usefulness of Carbon Dioxide Angiography and Intravascular Ultrasound: A Case Report

    PubMed Central

    Morito, Haruna; Hoshina, Katsuyuki; Hosaka, Akihiro; Okamoto, Hiroyuki; Shigematsu, Kunihiro; Miyata,, Tetsuro

    2012-01-01

    We report a patient with inflammatory abdominal aortic aneurysm who underwent endovascular aneurysm repair, despite his having an allergy to iodinated contrast medium and anatomy unsuitable for the procedure. Intravascular ultrasound-guided and CO2-assisted aortic stent graft placement was performed, and the procedures resulted in the successful exclusion of the aneurysm with regression of the mantle sign and resolution of hydronephrosis. PMID:23555498

  9. Long-term renin-angiotensin blocking therapy in hypertensive patients with normal aorta may attenuate the formation of abdominal aortic aneurysms.

    PubMed

    Silverberg, Daniel; Younis, Anan; Savion, Naphtali; Harari, Gil; Yakubovitch, Dmitry; Sheick Yousif, Basheer; Halak, Moshe; Grossman, Ehud; Schneiderman, Jacob

    2014-08-01

    Renin-angiotensin system (RAS) has been implicated in the pathogenesis of abdominal aortic aneurysm (AAA). Angiotensin II type 1 receptor blocker (ARB), when given with angiotensin II prevents AAA formation in mice, but found ineffective in attenuating the progression of preexisting AAA. This study was designed to evaluate the effect of chronic RAS blockers on abdominal aortic diameter in hypertensive patients without known aortic aneurysm. Consecutive hypertensive outpatients (n = 122) were stratified according to antihypertensive therapy they received for 12 months or more, consisting of ARB (n = 45), angiotensin converting enzyme inhibitor (ACE-I; n = 45), or nonARB/nonACE-I (control therapy; n = 32). Abdominal ultrasonography was performed to measure maximal subrenal aortic diameter. Eighty-four patients were reexamined by ultrasonography 8 months later. The correlation between the different antihypertensive therapies and aortic diameter was examined. Aortic diameters were significantly smaller in ARB than in control patients in the baseline and follow-up measurements (P = .004; P = .0004, respectively). Risk factor adjusted covariance analysis showed significant differences between ARB or ACE-I treated groups and controls (P = .006 or P = .046, respectively). Ultrasound that was performed 8 months later showed smaller increases in mean aortic diameters of the ARB and ACE-I groups than in controls. Both ARB and ACE-I therapy attenuated expansion of nonaneurysmal abdominal aorta in humans. These results indicate that RAS blockade given before advancement of aortic medial remodeling may slow down the development of AAA.

  10. Numerical study of purely viscous non-Newtonian flow in an abdominal aortic aneurysm.

    PubMed

    Marrero, Victor L; Tichy, John A; Sahni, Onkar; Jansen, Kenneth E

    2014-10-01

    It is well known that blood has non-Newtonian properties, but it is generally accepted that blood behaves as a Newtonian fluid at shear rates above 100 s-1. However, in transient conditions, there are times and locations where the shear rate is well below 100 s-1, and it is reasonable to infer that non-Newtonian effects could become important. In this study, purely viscous non-Newtonian (generalized Newtonian) properties of blood are incorporated into the simulation-based framework for cardiovascular surgery planning developed by Taylor et al. (1999, "Predictive Medicine: Computational Techniques in Therapeutic Decision Making," Comput. Aided Surg., 4, pp. 231-247; 1998, "Finite Element Modeling of Blood Flow in Arteries," Comput. Methods Appl. Mech. Eng., 158, pp. 155-196). Equations describing blood flow are solved in a patient-based abdominal aortic aneurysm model under steady and physiological flow conditions. Direct numerical simulation (DNS) is used, and the complex flow is found to be constantly transitioning between laminar and turbulent in both the spatial and temporal sense. It is found for the case simulated that using the non-Newtonian viscosity modifies the solution in subtle ways that yield a mesh-independent solution with fewer degrees of freedom than the Newtonian counterpart. It appears that in regions of separated flow, the lower shear rate produces higher viscosity with the non-Newtonian model, which reduces the associated resolution needs. When considering the real case of pulsatile flow, high shear layers lead to greater unsteadiness in the Newtonian case relative to the non-Newtonian case. This, in turn, results in a tendency for the non-Newtonian model to need fewer computational resources even though it has to perform additional calculations for the viscosity. It is also shown that both viscosity models predict comparable wall shear stress distribution. This work suggests that the use of a non-Newtonian viscosity models may be attractive

  11. Evaluation of the harmonic scalpel in open surgery for abdominal aortic aneurysm.

    PubMed

    Wu, Zeyu; Chen, Zhe; Peng, Lin

    2012-03-01

    The harmonic scalpel is a hemostatic device primarily designed for use in laparoscopic surgery. During the last few years, many surgeons have begun to use the harmonic scalpel in open surgery. Several papers have cited the benefits of the device compared with conventional knot-tying techniques; however, no evidence showing the advantages of using the harmonic scalpel in complicated abdominal aortic aneurysm (AAA) surgery has been presented. The aim of the present study is to determine the value of the harmonic scalpel in open operation for AAA. A total of 153 patients who underwent open surgery for AAA at the Department of Vascular Surgery of Guangdong General Hospital, China between January 2001 and December 2010, were retrospectively analyzed. Open surgery performed with the harmonic scalpel on 105 patients was compared with open operation using conventional knot-tying techniques on 48 patients. The operative time, intraoperative blood loss, total postoperative drainage fluid volumes, hospital stay, and postoperative complications between the two groups were compared. The harmonic scalpel group was associated with a shorter operation time (113.2 ± 23.6 min vs. 232.1 ± 39.2 min, P < 0.01) and lower intraoperative blood loss (126.1 ± 96.6 ml vs. 592.1 ± 207.2 ml, P < 0.01). Postoperative drainage fluid volumes were greater in the conventional surgery group than in the harmonic scalpel group (702.1 ± 192.8 ml vs. 198.5 ± 97.4 ml, P < 0.01). The hospital stay was shorter for the harmonic scalpel group than for the conventional surgery group (10.7 ± 3.3 d vs. 16.5 ± 4.7 d, P < 0.05). No differences between the postoperative complications or hospital mortality of the two groups were found. The harmonic scalpel is a safe and minimally invasive tool in open surgery for AAA and is associated with shorter operative time, shorter hospital stay, and lower intraoperative blood loss and postoperative drainage fluid volumes compared with conventional knot

  12. Causes of late mortality after endovascular and open surgical repair of infrarenal abdominal aortic aneurysms

    PubMed Central

    Goodney, Philip P.; Tavris, Dale; Lucas, F. Lee; Gross, Thomas; Fisher, Elliott S.; Finlayson, Samuel R. G.

    2017-01-01

    Introduction Several reports suggest unexpectedly high rates of late abdominal aortic aneurysm (AAA) rupture occur after endovascular AAA repair (EVAR). However, a population-based study examining causes of late death after EVAR vs open surgical repair has not been performed. Methods We performed a retrospective cohort study of patients undergoing infrarenal AAA repair using information from the Medicare inpatient hospital discharge records (MedPAR files), physician claim files (Part B files, 20% sample), and Medicare Denominator Files for the years 2001 to 2004. Using the Social Security Death Index, we identified all “late” deaths, defined as deaths occurring >30 days and after hospital discharge. We used the National Death Index to identify cause of death information; in particular, those deaths that were likely caused by late rupture. We compared causes of late death and survival between EVAR and open repair using Wilcoxon log-rank and rank-sum tests. Results Between 2001 and 2004, 13,971 patients underwent AAA repair (6119 EVAR, 7852 open repair). After a mean follow-up of 1.6 years in the EVAR cohort and 1.9 years in the open cohort, mortality rates were similar across repair type (15.4% EVAR, 15.9% open repair), with an adjusted odds ratio for death after open repair of 0.98 (95% confidence interval, 0.90–1.07). Of the 2194 documented deaths, 523 occurred before discharge or ≤30 days, and 1671 occurred >30 days and after hospital discharge. Cause of death information for the 1671 late deaths was available from the National Death Index for 1515 (91%). The 15 most common codes for causes of late death were dominated by cardiac disease (atherosclerotic heart disease, acute myocardial infarction) and pulmonary disease (lung cancer, respiratory failure). Causes of late death with specific mention of aneurysm were identified in 37 patients (2.4% of all deaths), but this event was not more common in EVAR or open repair (15 [0.3%] in the EVAR group, 22 [0

  13. Changes in Abdominal Aortic Aneurysm Rupture and Short Term Mortality 1995–2008

    PubMed Central

    Schermerhorn, Marc L.; Bensley, Rodney P.; Giles, Kristina A.; Hurks, Rob; O’Malley, A. James; Cotterill, Philip; Chaikof, Elliot; Landon, Bruce E.

    2012-01-01

    Objective To examine the modern epidemiology of abdominal aortic aneurysm (AAA) rupture and short-term AAA-related mortality after the introduction of endovascular aneurysm repair (EVAR). Background Prior epidemiologic studies have demonstrated stable rates of AAA repair, repair mortality, and AAA rupture. Recently, EVAR has been introduced as a less invasive treatment method and its use has expanded to over 75% of elective AAA repairs. Methods We identified Medicare beneficiaries undergoing AAA repair and those hospitalized with a ruptured AAA during the period 1995–2008 and calculated standardized annual rates of AAA-related deaths due to either elective repair or rupture. Results 338,278 patients underwent intact AAA repair over the study period. There were 69,653 patients with AAA rupture of whom 47,524 underwent repair. Intact repair rates increased substantially in those over age 80 (57.7 to 92.3 per 100,000, P<0.001), but decreased in those aged 65–74 (81.8 to 68.9, P<0.001). A decline in ruptures with and without repair was seen in all age groups. By 2008, 77% of all intact repairs and 31% of all rupture repairs were performed with EVAR (P<0.001). Operative mortality declined over the study period for both intact (4.9% to 2.4%, P<0.001) and ruptured (44.1% to 36.3%, P<0.001) AAA repair. Short-term AAA-related deaths decreased by more than half (26.1 to 12.1 per 100,000, P<0.001) with the greatest decline occurring in those over age 80 (53.7 to 27.3, P<0.001). Conclusions A recent decline in AAA rupture and short-term AAA-related mortality is demonstrated and likely related in part to the introduction and expansion of EVAR. This is due to decreased deaths from ruptures (with and without repair) and decreased mortality with intact repairs, particularly in patients over age 80. PMID:22964737

  14. Resident and fellow experiences after the introduction of endovascular aneurysm repair for abdominal aortic aneurysm

    PubMed Central

    Sachs, Teviah; Schermerhorn, Marc; Pomposelli, Frank; Cotterill, Philip; O’Malley, James; Landon, Bruce

    2015-01-01

    Objectives This study assessed trends in open and endovascular repair (EVAR) of intact and ruptured abdominal aortic aneurysm (AAA) in the Medicare population and evaluated recent trends in AAA repair at vascular fellowship training programs. Methods We identified all Medicare beneficiaries with a diagnosis of AAA who underwent repair or had a primary diagnosis of rupture (1995–2008). Cohorts were compared by type of repair (open vs EVAR) and presentation (intact vs ruptured AAA). Demographics of age, sex, and race were evaluated. We used unique hospital identifier codes to compare trends and 30-day mortality between hospitals that participate in vascular surgery fellowship training and those that do not. American Council on Graduate Medical Education data, only available for the years 1999 to 2008, were further used to better understand the changes in number of EVAR and open repairs of AAA performed each year for vascular fellows and general surgery residents, over time. Results We identified 449,122 patients (76% men), with 376,355 intact AAAs (84%) and 72,767 ruptured AAAs (16%). Mean age was 75.1 years. Use of EVAR for intact AAA rose to from 35% in 2001 to 63% in 2005 and comprised 78% of repairs by 2008. During the same period, the number of ruptured AAAs decreased by 40% overall, with nonoperative ruptured AAAs decreasing by 29% and EVAR increasing to 31% of rupture repairs. Hospitals training vascular fellows were quicker to adopt EVAR (2-year lag time) for intact AAA and had higher rates of EVAR for ruptured AAA (41.1% vs 29.2%; P = .001) than did hospitals without fellows. Mortality rates for open repairs of intact (4.0% vs 5.0%; P = .01) and ruptured AAA (34.1% vs 41.0%; P = .031) were lower at fellowship hospitals. The average number of open AAA repairs performed by vascular fellows dropped 50% (44.1 to 21.6/year) from 1999 to 2008. Conclusions Contrary to the expectation of a plateau, use of EVAR for intact AAA continues to rise at fellowship and

  15. Lower Extremity Microembolism in Open vs. Endovascular Abdominal Aortic Aneurysm Repair

    PubMed Central

    Toursavadkohi, Shahab; Kakkos, Stavros K.; Rubinfeld, Ilan; Shepard, Alexander

    2016-01-01

    Although previous studies have documented the occurrence of microembolization during abdominal aortic aneurysm (AAA) repair by both open and endovascular approaches, no study has compared the downstream effects of these two repair techniques on lower extremity hemodynamics. In this prospective cohort study, 20 patients were treated with endovascular aneurysm repair (EVAR) (11 Zenith, 8 Excluder, and 1 Medtronic) and 18 patients with open repair (OR) (16 bifurcated grafts, 2 tube grafts). Pre- and postoperative ankle-brachial indices (ABIs) and toe-brachial indices (TBIs) were measured preoperatively and on postoperative day (POD) 1 and 5. Demographics and preoperative ABIs/TBIs were identical in EVAR (0.97/0.63) and OR (0.96/0.63) patients (p = 0.21). There was a significant decrease in ABIs/TBIs following both EVAR (0.83/0.52, p = 0.01) and OR (0.73/0.39, p = 0.003) on POD #1, although this decrease was greater following OR than EVAR (p = 0.002). This difference largely resolved by POD #5 (p = 0.41). In the OR group, TBIs in the limb in which flow was restored first was significantly reduced compared to the contralateral limb (0.50 vs. 0.61, p = 0.03). In the EVAR group, there was also a difference in TBIs between the main body insertion side and the contralateral side (0.50 vs. 0.59, p = 0.02). Deterioration of lower extremity perfusion pressures occurs commonly after AAA repair regardless of repair technique. Toe perfusion is worse in the limb opened first during OR and on the main body insertion side following EVAR, suggesting that microembolization plays a major role in this deterioration. The derangement following OR is more profound than after EVAR on POD #1, but recovers rapidly. This finding suggests that microembolizarion may be worse with OR or alternatively that other factors associated with OR (e.g., the hemodynamic response to surgery with redistribution of flow to vital organs peri-operatively) may play a role. PMID

  16. Development, Implementation, and Evaluation of a Structured Reporting Web Tool for Abdominal Aortic Aneurysms

    PubMed Central

    Karim, Sulafa; Fegeler, Christian; Boeckler, Dittmar; H Schwartz, Lawrence; Kauczor, Hans-Ulrich

    2013-01-01

    Background The majority of radiological reports are lacking a standard structure. Even within a specialized area of radiology, each report has its individual structure with regards to details and order, often containing too much of non-relevant information the referring physician is not interested in. For gathering relevant clinical key parameters in an efficient way or to support long-term therapy monitoring, structured reporting might be advantageous. Objective Despite of new technologies in medical information systems, medical reporting is still not dynamic. To improve the quality of communication in radiology reports, a new structured reporting system was developed for abdominal aortic aneurysms (AAA), intended to enhance professional communication by providing the pertinent clinical information in a predefined standard. Methods Actual state analysis was performed within the departments of radiology and vascular surgery by developing a Technology Acceptance Model. The SWOT (strengths, weaknesses, opportunities, and threats) analysis focused on optimization of the radiology reporting of patients with AAA. Definition of clinical parameters was achieved by interviewing experienced clinicians in radiology and vascular surgery. For evaluation, a focus group (4 radiologists) looked at the reports of 16 patients. The usability and reliability of the method was validated in a real-world test environment in the field of radiology. Results A Web-based application for radiological “structured reporting” (SR) was successfully standardized for AAA. Its organization comprises three main categories: characteristics of pathology and adjacent anatomy, measurements, and additional findings. Using different graphical widgets (eg, drop-down menus) in each category facilitate predefined data entries. Measurement parameters shown in a diagram can be defined for clinical monitoring and be adducted for quick adjudications. Figures for optional use to guide and standardize the

  17. Variations in Abdominal Aortic Aneurysm Care: A Report From the International Consortium of Vascular Registries

    PubMed Central

    Sedrakyan, Art; Mao, Jialin; Venermo, Maarit; Faizer, Rumi; Debus, Sebastian; Behrendt, Christian-Alexander; Scali, Salvatore; Altreuther, Martin; Schermerhorn, Marc; Beiles, Barry; Szeberin, Zoltan; Eldrup, Nikolaj; Danielsson, Gudmundur; Thomson, Ian; Wigger, Pius; Björck, Martin; Cronenwett, Jack L.; Mani, Kevin

    2016-01-01

    Background: This project by the ICVR (International Consortium of Vascular Registries), a collaboration of 11 vascular surgical quality registries, was designed to evaluate international variation in the contemporary management of abdominal aortic aneurysm (AAA) with relation to recommended treatment guidelines from the Society for Vascular Surgery and the European Society for Vascular Surgery. Methods: Registry data for open and endovascular AAA repair (EVAR) during 2010 to 2013 were collected from 11 countries. Variations in patient selection and treatment were compared across countries and across centers within countries. Results: Among 51 153 patients, 86% were treated for intact AAA (iAAA) and 14% for ruptured AAA. Women constituted 18% of the entire cohort (range, 12% in Switzerland–21% in the United States; P<0.01). Intact AAAs were repaired at diameters smaller than recommended by guidelines in 31% of men (<5.5 cm; range, 6% in Iceland–41% in Germany; P<0.01) and 12% of women with iAAA (<5 cm; range, 0% in Iceland–16% in the United States; P<0.01). Overall, use of EVAR for iAAA varied from 28% in Hungary to 79% in the United States (P<0.01) and for ruptured AAA from 5% in Denmark to 52% in the United States (P<0.01). In addition to the between-country variations, significant variations were present between centers in each country in terms of EVAR use and rate of small AAA repair. Countries that more frequently treated small AAAs tended to use EVAR more frequently (trend: correlation coefficient, 0.51; P=0.14). Octogenarians made up 23% of all patients, ranging from 12% in Hungary to 29% in Australia (P<0.01). In countries with a fee-for-service reimbursement system (Australia, Germany, Switzerland, and the United States), the proportions of small AAA (33%) and octogenarians undergoing iAAA repair (25%) were higher compared with countries with a population-based reimbursement model (small AAA repair, 16%; octogenarians, 18%; P<0.01). In general

  18. Inflammatory abdominal aortic aneurysm: close relationship to IgG4-related periaortitis.

    PubMed

    Kasashima, Satomi; Zen, Yoh; Kawashima, Atsuhiro; Konishi, Keiko; Sasaki, Hisao; Endo, Masamitsu; Matsumoto, Yasushi; Kawakami, Kengo; Kasashima, Fuminori; Moriya, Makio; Kimura, Keiichi; Ohtake, Hiroshi; Nakanuma, Yasuni

    2008-02-01

    Inflammatory abdominal aortic aneurysm (AAA) is a member of a family of disorders referred to as "chronic periaortitis" together with retroperitoneal fibrosis. Retroperitoneal fibrosis is included in IgG4-related disease, which is characterized by numerous infiltrating IgG4-positive plasma cells and high serum IgG4 concentrations. However, the relationship between IgG4-related disease and inflammatory AAA has not been documented. In this study, we examined the clinicopathologic characteristics of inflammatory (10 cases) and atherosclerotic (22 cases) AAAs, based on the hypothesis that inflammatory AAA might be related to IgG4-related disease. Cases of inflammatory AAA could be classified into 2 groups based on immunostaining of IgG4. Four patients showed diffuse infiltration of abundant IgG4-positive plasma cells (IgG4-related cases), whereas the remaining 6 cases of inflammatory AAA and all cases of atherosclerotic AAA had only a few IgG4-positive plasma cells (non-IgG4-related cases). IgG4-related inflammatory AAA was pathologically characterized by the frequent infiltration of eosinophils, lymph follicle formation, perineural inflammatory extension, and inconspicuous infiltration of neutrophils compared with non-IgG4-related inflammatory AAA. Obliterative phlebitis, which is venous occlusion with inflammatory cell infiltration, is observed in all IgG4-related cases. In addition, serum IgG4 concentrations were significantly higher in IgG4-related inflammatory AAA (109 to 559 mg/dL, normal range: 4 to 110 mg/dL) than non-IgG4-related inflammatory AAA (32 to 59 mg/dL) and all atherosclerotic AAA (12 to 83 mg/dL). In conclusion, inflammatory AAAs might be classified into 2 groups: IgG4-related or nonrelated. The former might be one of the IgG4-related diseases, and could be included in IgG4-related periaortitis together with retroperitoneal fibrosis.

  19. A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta

    PubMed Central

    Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

    2016-01-01

    Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery. PMID:27029949

  20. Cardiopulmonary exercise testing in the pre-operative assessment of patients for repair of abdominal aortic aneurysm.

    PubMed

    Nugent, A M; Riley, M; Megarry, J; O'Reilly, M J; MacMahon, J; Lowry, R

    1998-01-01

    We have investigated the value of cardiopulmonary exercise testing in the pre-operative assessment to patients for abdominal aortic aneurysm repair. Thirty-six patients were entered into the study. All had a pre-operative clinical assessment and investigations including chest radiograph, electrocardiograph, spirometry and echocardiogram with measurement of left ventricular ejection fraction. Each patient performed a symptom limited treadmill exercise test using a STEEP protocol with on-line measurement of respiratory gas exchange. Patients were followed up for 12 months post-operatively by review of casenotes. Thirty out of 36 patients had surgical repair of abdominal aortic aneurysm. There was 1 death in the perioperative period and 2 deaths in the following 12 months. Seven other patients suffered post-operative complications. There were no significant differences in left ventricular ejection fraction, spirometry and peak achieved oxygen consumption (PVO2) between those patients who died or who had post-operative complications and those who had not. However, PVO2 < 20 ml/min/kg was found in 70 per cent of patients who had complications compared with 50 per cent of those who had not. Also 4 patients considered medically unfit for surgery all had PVO2 < 20 ml/min/kg. Cardiopulmonary exercise testing with measurement of PVO2 may be helpful in identifying patients more at risk of post-operative complications but should not be used in isolation without through clinical assessment.

  1. A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta.

    PubMed

    Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

    2016-03-31

    Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery.

  2. A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta

    NASA Astrophysics Data System (ADS)

    Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

    2016-03-01

    Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery.

  3. Fourier Transform Infrared Spectroscopic Imaging-Derived Collagen Content and Maturity Correlates with Stress in the Aortic Wall of Abdominal Aortic Aneurysm Patients.

    PubMed

    Cheheltani, Rabee; Pichamuthu, Joseph E; Rao, Jayashree; Weinbaum, Justin S; Kiani, Mohammad F; Vorp, David A; Pleshko, Nancy

    2017-03-01

    Abdominal aortic aneurysm (AAA) is a degenerative disease of the aorta characterized by severe disruption of the structural integrity of the aortic wall and its major molecular constituents. From the early stages of disease, elastin in the aorta becomes highly degraded and is replaced by collagen. Questions persist as to the contribution of collagen content, quality and maturity to the potential for rupture. Here, using our recently developed Fourier transform infrared imaging spectroscopy (FT-IRIS) method, we quantified collagen content and maturity in the wall of AAA tissues in pairs of specimens with different wall stresses. CT scans of AAAs from 12 patients were used to create finite element models to estimate stress in different regions of tissue. Each patient underwent elective repair of the AAA, and two segments of the AAA tissues from anatomic regions more proximal or distal with different wall stresses were evaluated by histology and FT-IRIS after excision. For each patient, collagen content was generally greater in the tissue location with lower wall stress, which corresponded to the more distal anatomic regions. The wall stress/collagen ratio was greater in the higher stress region compared to the lower stress region (1.01 ± 1.09 vs. 0.55 ± 0.084, p = 0.02). The higher stress region also corresponded to the location with reduced intraluminal thrombus thickness. Further, collagen maturity tended to decrease with increased collagen content (p = 0.068, R = 0.38). Together, these results suggest that an increase in less mature collagen content in AAA patients does not effectively compensate for the loss of elastin in the aortic wall, and results in a reduced capability to endure wall stresses.

  4. The ω-3 Polyunsaturated Fatty Acid, Eicosapentaenoic Acid, Attenuates Abdominal Aortic Aneurysm Development via Suppression of Tissue Remodeling

    PubMed Central

    Wang, Jack H.; Eguchi, Kosei; Matsumoto, Sahohime; Fujiu, Katsuhito; Komuro, Issei; Nagai, Ryozo; Manabe, Ichiro

    2014-01-01

    Abdominal aortic aneurysm (AAA) is a prevalent vascular disease that can progressively enlarge and rupture with a high rate of mortality. Inflammation and active remodeling of the aortic wall have been suggested to be critical in its pathogenesis. Meanwhile, ω-3 polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) are known to reduce cardiovascular events, but its role in AAA management remains unclear. Here, we show that EPA can attenuate murine CaCl2-induced AAA formation. Aortas from BALB/c mice fed an EPA-diet appeared less inflamed, were significantly smaller in diameter compared to those from control-diet-fed mice, and had relative preservation of aortic elastic lamina. Interestingly, CT imaging also revealed markedly reduced calcification of the aortas after EPA treatment. Mechanistically, MMP2, MMP9, and TNFSF11 levels in the aortas were reduced after EPA treatment. Consistent with this finding, RAW264.7 macrophages treated with EPA showed attenuated Mmp9 levels after TNF-α simulation. These results demonstrate a novel role of EPA in attenuating AAA formation via the suppression of critical remodeling pathways in the pathogenesis of AAAs, and raise the possibility of using EPA for AAA prevention in the clinical setting. PMID:24798452

  5. Quantification of hemodynamics in abdominal aortic aneurysms during rest and exercise using magnetic resonance imaging and computational fluid dynamics.

    PubMed

    Les, Andrea S; Shadden, Shawn C; Figueroa, C Alberto; Park, Jinha M; Tedesco, Maureen M; Herfkens, Robert J; Dalman, Ronald L; Taylor, Charles A

    2010-04-01

    Abdominal aortic aneurysms (AAAs) affect 5-7% of older Americans. We hypothesize that exercise may slow AAA growth by decreasing inflammatory burden, peripheral resistance, and adverse hemodynamic conditions such as low, oscillatory shear stress. In this study, we use magnetic resonance imaging and computational fluid dynamics to describe hemodynamics in eight AAAs during rest and exercise using patient-specific geometric models, flow waveforms, and pressures as well as appropriately resolved finite-element meshes. We report mean wall shear stress (MWSS) and oscillatory shear index (OSI) at four aortic locations (supraceliac, infrarenal, mid-aneurysm, and suprabifurcation) and turbulent kinetic energy over the entire computational domain on meshes containing more than an order of magnitude more elements than previously reported results (mean: 9.0-million elements; SD: 2.3 M; range: 5.7-12.0 M). MWSS was lowest in the aneurysm during rest 2.5 dyn/cm(2) (SD: 2.1; range: 0.9-6.5), and MWSS increased and OSI decreased at all four locations during exercise. Mild turbulence existed at rest, while moderate aneurysmal turbulence was present during exercise. During both rest and exercise, aortic turbulence was virtually zero superior to the AAA for seven out of eight patients. We postulate that the increased MWSS, decreased OSI, and moderate turbulence present during exercise may attenuate AAA growth.

  6. POST-TRAUMATIC APICAL LEFT VENTRICULAR ANEURYSM IN A PATIENT WITH LEFT VENTRICULAR APICAL-ABDOMINAL AORTIC CONDUIT: CASE PRESENTATION

    PubMed Central

    Ugorji, Clement C.; Cooley, Denton A.; Norman, John C.

    1979-01-01

    A patient with a small aortic annulus had an apico-aortic conduit implanted for aortic stenosis approximately three years before being admitted to our institution. Four months after sustaining a steering wheel injury to the chest, he developed chest pain and palpitations. X-ray films and left ventriculograms revealed a large apical aneurysm of unknown duration. At surgery, it was noted that the proximal portion of the conduit had been sewn directly to the myocardium without the use of a rigid or soft apical outlet prosthesis incorporating a sewing ring. The aneurysm was resected along with a small proximal segment of the conduit graft. A polished Pyrolite® rigid inlet tube with a sewing ring and graft extension was inserted into the residual left ventricular apex, and continuity was reestablished with the abdominal segment of the conduit. It is postulated that the aneurysm was caused by either the direct anastomosis of the fabric graft to the apical myocardium at the original operation (with subsequent disruption and aneurysm formation prior to the steering wheel injury), or was the result of fixation of the heart at the diaphragm by the conduit, with increased vulnerability to deceleration injury at the direct left ventricular apex myocardium-fabric graft site. Images PMID:15216296

  7. [Ischemia of the large intestine after simultaneous kidney transplantation and aortic replacement with a fresh graft in an abdominal aortic aneurysm].

    PubMed

    Matia, I; Adamec, M; Fronĕk, J; Tosenovský, P; Janousek, L; Baláz, P; Langer, D; Lipár, K; Lácha, J

    2004-03-01

    Fresh arterial grafts obtained during multi-organ excisions widen a spectrum of treatment possibilities for obliterating arterial disorders of low extremities or for the abdominal aortic aneurysm in patients waiting for organ transplantation. Between the year 1998 and the end of the year 2002, our work-team performed parallel reconstructions of the abdominal aorta using fresh grafts and cadaverous kidney transplantations in a group of five patients. The simultaneous surgical treatment of the both disorders during a single hospitalization as well as a considerable decrease of the artificial blood vessel prosthesis infection risk during chronic imunosuppression, represent the biggest advantage of this method. On the other hand, the risk of possible surgical complications is increased in these patients. During the operation and postoperation period, our four patients suffered from no serious complications. In case of one patient, ischemic colitis occurred which required surgical revision and subtotal colectomy. In this article, the authors describe the postoperation course of the patient condition with the above complication, which required a close cooperation of surgeons, anesthesiologists and nephrologists, in full detail.

  8. Mechanical Strain Induced Expression of Matrix Metalloproteinase-9 via Stretch-Activated Channels in Rat Abdominal Aortic Dissection

    PubMed Central

    Qiu, ZhiHuang; Chen, LiangWan; Cao, Hua; Chen, Qiang; Peng, Hua

    2017-01-01

    Background The aim of the study was to investigate the expression of matrix metalloproteinase-9 (MMP-9) in rat abdominal aortic dissection (AD) induced by mechanical strain, so as to offer a better understanding of the possible mechanisms of AD. Material/Methods Experimental AD in rats was achieved by the injection of porcine pancreatic elastase. At days 0, 1, 3, 5, 7, 14, 21, and 30 after the establishment of AD model, serum MMP-9 levels were measured by enzyme-linked immunosorbent assay (ELISA). Four groups of vascular rings were stretched in vitro with a mechanical strength of 0 g, 1 g, 3 g, or 5 g for 30 min. Another four groups were pretreated with GdCl3, streptomycin, SN50, and SN50M, followed by stretching with 3 g for 30 min. The messenger RNA and the protein of MMP-9 were analyzed by real-time RT-PCR and Western blotting, and NF-κB p65 was detected by ELISA. Results After the establishment of rat abdominal AD model, the serum MMP-9 levels of AD groups increased significantly. The results showed increased expression of MMP-9 in rat AD vessels stretched with mechanical strength of 1 g, 3 g, and 5 g, but this effect was mostly blocked by Gd Cl3 and streptomycin. The NF-κB activity in aortic rings was activated by stretching with a mechanical strength of 3 g and was blocked by SN50, but not by SN50M. Conclusions The expression of MMP-9 in serum was increased significantly after rat abdominal AD formation. Mechanical strain induced MMP-9 expression in AD vessels, which was mediated through the activation of the stretch-activated channel-induced NF-κB pathway. PMID:28286334

  9. A case of immunoglobulin G4-related constrictive pericarditis

    PubMed Central

    Luo, Wen-Qi; Fang, Fang; Zhen, Wen-Jun; Ouyang, Xiao-Kang; Wang, Huai-Bin; Wang, Zi

    2016-01-01

    A 47-year-old man was admitted with a complaint of upper abdominal distension and shortness of breath. The constrictive pericarditis was diagnosed based on the transthoracic echocardiogram (TTE) and chest CT scan. Pathology revealed it is immunoglobulin (Ig) G4-related constrictive pericarditis. Likely, this is the first case of IgG4-related constrictive pericarditis reported in China. PMID:26904579

  10. Measuring of Abdominal Aortic Aneurysm with Three-Dimensional Computed Tomography Reconstruction before Endovascular Aortic Aneurysm Repair

    PubMed Central

    Chung, Yoona; Joh, Jin Hyun; Park, Ho-Chul

    2017-01-01

    Purpose Conventional computed tomography (CT) is the gold standard method for case planning for endovascular aortic aneurysm repair (EVAR). However, aortography with a marking catheter is needed for measuring the actual length of an aneurysm. With advances in imaging technology, a 3-dimensional (3D) workstation can obviate the need for the aortography. The objective of this study was to determine whether a 3D workstation could obviate the need for aortography for EVAR. Materials and Methods One vascular surgeon and 1 interventional radiologist retrospectively assessed axial CT scans and reformatted the 3D CT scans by using the iNtuition workstation (TeraRecon Inc., San Mateo, CA, USA) for 25 patients who underwent EVAR. Four measurements of diameter and length were obtained from each modality. The actual length of an aneurysm for the proper graft was decided by 2 observers by reviewing the aortography with a marking catheter. Results The measurements from the 2 modalities were reproducible with intraobserver correlation coefficients of 0.89 to 1.0 for conventional CT and 0.98 to 1.0 for 3D workstation. Interobserver correlation coefficients were 0.29 to 0.95 for conventional CT and 0.85 to 0.99 for the 3D workstation. The length of the aneurysm for proper main graft coincided in 18 and 14 patients according to the conventional CT scan and in 21 and 18 patients according to the 3D workstation, respectively. Conclusion The interobserver agreement in planning EVAR was significantly better with the iNtuition 3D workstation. But aortography with a marking catheter may still be needed for selecting the proper graft. PMID:28377909

  11. Feasibility of Angioplasty and Stenting for Abdominal Aortic Lesions Adjacent to Previously Stented Visceral Artery Lesions in Patients with Takayasu Arteritis

    SciTech Connect

    Joseph, George George, Paul V.; Pati, Purendra Kumar; Chandy, Sunil Thomas

    2007-04-15

    Two young female patients with Takayasu arteritis presented with symptomatic long-segment abdominal aortic stenosis in the vicinity of previously deployed celiac and renal artery stents that projected markedly into the narrowed aortic lumen. Crushing or distortion of the visceral artery stents during aortic angioplasty was avoided by performing simultaneous or alternating balloon dilatations in the aorta and in the visceral artery stents. Consequently, the visceral artery stents remained patent and shortened longitudinally, allowing unhindered deployment of Wallstents in the adjacent aorta and abolition of a pressure gradient across the aortic lesions. Access to side branches covered by the Wallstent was obtained without difficulty, enabling the performance of balloon dilatation in multiple side branches and ostial stent deployment in a renal artery. These techniques could increase the scope of endovascular therapy in the treatment of patients with Takayasu arteritis.

  12. Chimney-Graft as a Bail-Out Procedure for Endovascular Treatment of an Inflammatory Juxtarenal Abdominal Aortic Aneurysm

    PubMed Central

    Fratesi, Francesca; Handa, Ashok; Uberoi, Raman; Sideso, Ediri

    2015-01-01

    Inflammatory and juxtarenal Abdominal Aortic Aneurysm (j-iAAA) represents a technical challenge for open repair (OR) due to the peculiar anatomy, extensive perianeurysmal fibrosis, and dense adhesion to the surrounding tissues. A 68-year-old man with an 11 cm asymptomatic j-iAAA was successfully treated with elective EVAR and chimney-graft (ch-EVAR) without postprocedural complications. Target vessel patency and normal renal function are present at 24-month follow-up. The treatment of j-iAAA can be technically challenging. ch-EVAR is a feasible and safe bail-out method for elective j-iAAA with challenging anatomy. PMID:26064770

  13. Scientific second-order 'nudging' or lobbying by interest groups: the battle over abdominal aortic aneurysm screening programmes.

    PubMed

    Ploug, Thomas; Holm, Søren; Brodersen, John

    2014-11-01

    The idea that it is acceptable to 'nudge' people to opt for the 'healthy choice' is gaining currency in health care policy circles. This article investigates whether researchers evaluating Abdominal Aortic Aneurysm Screening Programmes (AAASP) attempt to influence decision makers in ways that are similar to popular 'nudging' techniques. Comparing two papers on the health economics of AAASP both published in the BMJ within the last 3 years, it is shown that the values chosen for the health economics modelling are not representative of the literature and consistently favour the conclusions of the articles. It is argued (1) that this and other features of these articles may be justified within a Libertarian Paternalist framework as 'nudging' like ways of influencing decision makers, but also (2) that these ways of influencing decision makers raise significant ethical issues in the context of democratic decision making.

  14. Effects of the flexibility of the arterial wall on the wall shear stresses and wall tension in Abdominal Aortic Aneurysms.

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Fernandez, Miguel; Chomaz, Jean-Marc

    2005-11-01

    As an abdominal aortic aneurysm develops, large changes occur in the composition and structure of the arterial wall, which result in its stiffening. So far, most studies, whether experimental or numerical, have been conducted assuming the walls to be rigid. A numerical simulation of the fluid structure interactions is performed in different models of aneurysms in order to analyze the effects that the wall compliance might have on the flow topology. Both symmetric and non-symmetric models of aneurysms are considered, all idealistic in shape. The wall mechanical properties are varied in order to simulate the progressive stiffening of the walls. The spatial and temporal distributions of wall tension are calculated for the different values of the wall elasticity and compared to the results for the rigid walls. In the case of rigid walls, the calculation of the wall shear stresses and pressure compare very well with experimental results.

  15. Seventeen Years’ Experience of Late Open Surgical Conversion after Failed Endovascular Abdominal Aortic Aneurysm Repair with 13 Variant Devices

    SciTech Connect

    Wu, Ziheng; Xu, Liang; Qu, Lefeng; Raithel, Dieter

    2015-02-15

    PurposeTo investigate the causes and results of late open surgical conversion (LOSC) after failed abdominal aortic aneurysm repair (EVAR) and to summarize our 17 years’ experience with 13 various endografts.MethodsRetrospective data from August 1994 to January 2011 were analyzed at our center. The various devices’ implant time, the types of devices, the rates and causes of LOSC, and the procedures and results of LOSC were analyzed and evaluated.ResultsA total of 1729 endovascular aneurysm repairs were performed in our single center (Nuremberg South Hospital) with 13 various devices within 17 years. The median follow-up period was 51 months (range 9–119 months). Among them, 77 patients with infrarenal abdominal aortic aneurysms received LOSC. The LOSC rate was 4.5 % (77 of 1729). The LOSC rates were significantly different before and after January 2002 (p < 0.001). The reasons of LOSC were mainly large type I endoleaks (n = 51) that were hard to repair by endovascular techniques. For the LOSC procedure, 71 cases were elective and 6 were emergent. The perioperative mortality was 5.2 % (4 of 77): 1 was elective (due to septic shock) and 3 were urgent (due to hemorrhagic shock).ConclusionLarge type I endoleaks were the main reasons for LOSC. The improvement of devices and operators’ experience may decrease the LOSC rate. Urgent LOSC resulted in a high mortality rate, while selective LOSC was relatively safe with significantly lower mortality rate. Early intervention, full preparation, and timely LOSC are important for patients who require LOSC.

  16. Andrographolide Ameliorates Abdominal Aortic Aneurysm Progression by Inhibiting Inflammatory Cell Infiltration through Downregulation of Cytokine and Integrin Expression

    PubMed Central

    Ren, Jun; Liu, Zhenjie; Wang, Qiwei; Giles, Jasmine; Greenberg, Jason; Sheibani, Nader; Kent, K. Craig

    2016-01-01

    Abdominal aortic aneurysm (AAA), characterized by exuberant inflammation and tissue deterioration, is a common aortic disease associated with a high mortality rate. There is currently no established pharmacological therapy to treat this progressive disease. Andrographolide (Andro), a major bioactive component of the herbaceous plant Andrographis paniculata, has been found to exhibit potent anti-inflammatory properties by inhibiting nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activity in several disease models. In this study, we investigated the ability of Andro to suppress inflammation associated with aneurysms, and whether it may be used to block the progression of AAA. Whereas diseased aortae continued to expand in the solvent-treated group, daily administration of Andro to mice with small aneurysms significantly attenuated aneurysm growth, as measured by the diminished expansion of aortic diameter (165.68 ± 15.85% vs. 90.62 ± 22.91%, P < 0.05). Immunohistochemistry analyses revealed that Andro decreased infiltration of monocytes/macrophages and T cells. Mechanistically, Andro inhibited arterial NF-κB activation and reduced the production of proinflammatory cytokines [CCL2, CXCL10, tumor necrosis factor α, and interferon-γ] in the treated aortae. Furthermore, Andro suppressed α4 integrin expression and attenuated the ability of monocytes/macrophages to adhere to activated endothelial cells. These results indicate that Andro suppresses progression of AAA, likely through inhibition of inflammatory cell infiltration via downregulation of NF-κB–mediated cytokine production and α4 integrin expression. Thus, Andro may offer a pharmacological therapy to slow disease progression in patients with small aneurysms. PMID:26483397

  17. Andrographolide Ameliorates Abdominal Aortic Aneurysm Progression by Inhibiting Inflammatory Cell Infiltration through Downregulation of Cytokine and Integrin Expression.

    PubMed

    Ren, Jun; Liu, Zhenjie; Wang, Qiwei; Giles, Jasmine; Greenberg, Jason; Sheibani, Nader; Kent, K Craig; Liu, Bo

    2016-01-01

    Abdominal aortic aneurysm (AAA), characterized by exuberant inflammation and tissue deterioration, is a common aortic disease associated with a high mortality rate. There is currently no established pharmacological therapy to treat this progressive disease. Andrographolide (Andro), a major bioactive component of the herbaceous plant Andrographis paniculata, has been found to exhibit potent anti-inflammatory properties by inhibiting nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activity in several disease models. In this study, we investigated the ability of Andro to suppress inflammation associated with aneurysms, and whether it may be used to block the progression of AAA. Whereas diseased aortae continued to expand in the solvent-treated group, daily administration of Andro to mice with small aneurysms significantly attenuated aneurysm growth, as measured by the diminished expansion of aortic diameter (165.68 ± 15.85% vs. 90.62 ± 22.91%, P < 0.05). Immunohistochemistry analyses revealed that Andro decreased infiltration of monocytes/macrophages and T cells. Mechanistically, Andro inhibited arterial NF-κB activation and reduced the production of proinflammatory cytokines [CCL2, CXCL10, tumor necrosis factor α, and interferon-γ] in the treated aortae. Furthermore, Andro suppressed α4 integrin expression and attenuated the ability of monocytes/macrophages to adhere to activated endothelial cells. These results indicate that Andro suppresses progression of AAA, likely through inhibition of inflammatory cell infiltration via downregulation of NF-κB-mediated cytokine production and α4 integrin expression. Thus, Andro may offer a pharmacological therapy to slow disease progression in patients with small aneurysms.

  18. Massive retroperitoneal tubercular abscess mimicking a leaking abdominal aortic aneurysm: a case report

    PubMed Central

    Singh, Pankaj K; Azam, Amir; Singh, Vinay K; Tomar, Juhi; Mishra, Alka; Singh, Kuldeep K; Gupta, Sanjeev

    2008-01-01

    In spite of being a common diagnosis in the patients of Asian origin, atypical presentations of tuberculosis may pose diagnostic challenges. We report a huge prevertebral abscess in a 30-year-old female, mimicking a leaking aortic aneurysm. The patient was managed successfully by emergency decompression and stabilization. The issues related to poor patient compliance to chemotherapy and management of atypical presentations of spinal tuberculosis are discussed here. PMID:18854051

  19. APICAL LEFT VENTRICULAR-ABDOMINAL AORTIC COMPOSITE CONDUITS FOR LEFT VENTRICULAR OUTFLOW OBSTRUCTIONS

    PubMed Central

    Cooley, Denton A.; Norman, John C.

    1978-01-01

    Certain problems related to the left ventricular outflow tract are not amenable to conventional surgical methods, but may be solved with the creation of a double outlet left ventricle by using a composite rigid pyrolite left ventricular apex outlet prosthesis and a fabric valve-containing conduit. Low porosity woven Dacron tube grafts are used for the conduit. Twenty-three patients who have undergone apico-aortic bypass with this conduit are reported here, with gratifying results in eighteen. PMID:15216062

  20. Inhibition of the mTOR pathway in abdominal aortic aneurysm: implication of smooth muscle cell contractile phenotype, inflammation and aneurysm expansion.

    PubMed

    Li, Guangxin; Qin, Lingfeng; Wang, Lei; Li, Xuan; Caulk, Alexander W; Zhang, Jian; Chen, Pei-Yu; Xin, Shijie

    2017-02-17

    The development of effective pharmacological treatment of abdominal aortic aneurysm (AAA) potentially offers great benefit to patients with pre-aneurysmal aortic dilation by slowing the expansion of aneurysms and reducing the need for surgery. To date, therapeutic targets for slowing aortic dilation have had low efficacy. Thus, in this study, we aim to elucidate possible mechanisms driving aneurysm progression in order to identify potential targets for pharmacological intervention. We demonstrate that mTOR signaling is over activated in aortic smooth muscle cells (SMCs) which contributes to murine AAA. Rapamycin, a typical mTOR pathway inhibitor, dramatically limits the expansion of the abdominal aorta following intraluminal elastase perfusion. Furthermore, reduction of aortic diameter is achieved by inhibition of the mTOR pathway, which preserves and/or restores the contractile phenotype of SMCs and downregulates macrophage infiltration, MMPs expression, and inflammatory cytokine production. Taken together, these results highlight the important role of the mTOR cascade in aneurysm progression and the potential application of rapamycin as a therapeutic candidate for AAA.

  1. [Anesthetic management of a patient with aortocaval fistula caused by rupture of a huge abdominal aortic aneurysm into the inferior vena cava].

    PubMed

    Tanaka, Motonari; Kawashima, Akira; Kuremoto, Yoshito; Tanada, Kazuko

    2013-12-01

    Aortocaval fistula is a rare complication of ruptured abdominal aortic aneurysm. We report anesthetic management of a patient with aortocaval fistula caused by rupture of a huge abdominal aortic aneurysm into the inferior vena cava. A 51-year-old man who had complained of low back pain and general fatigue was referred to our hospital because of his liver damage. Aortocaval fistula due to rupture of a huge abdominal aortic aneurysm was diagnosed from physical examination, enhanced computed tomography and color Doppler ultrasonography. Anesthesia was induced with propofol and rocuronium, and was maintained with sevoflurane and remifentanil. After induction of anesthesia, the central venous pressure and cardiac index showed remarkably high values because of arteriovenous shunt. When the aneurysm was incised after the clamping of the abdominal aorta, massive venous bleeding occurred from the fistula and caused severe hypotension. Blood pressure recovered by digital compression of the bleeding point and the use of an autotransfusion device. After the repair of the aortocaval fistula, the hemodynamics became stable. The patient had a high output but a good cardiac function in preoperative examination. Therefore anesthesia was managed successfully without worsening high-output heart failure.

  2. Aortic Aneurysm

    MedlinePlus

    ... these occur in the part of the aorta running through the chest Abdominal aortic aneurysms (AAA) - these occur in the part of the aorta running through the abdomen Most aneurysms are found during ...

  3. Evaluation of the CritiView in pig model of abdominal aortic occlusion and graded hemorrhage

    NASA Astrophysics Data System (ADS)

    Mayevsky, A.; Preisman, S.; Willenz, P. E.; Castel, D.; Perel, A.; Givony, D.; Dekel, N.; Oren, L.; Pewzner, E.

    2009-02-01

    We hypothesize that in the presence of reduced oxygen delivery and extraction, blood flow will be redistributed in order to protect the most vital organs (e.g., brain and heart) by increasing their regional blood flow, while O2 delivery to the less vital organs (e.g., GI tract or urethral wall) will diminish. Evaluation of mitochondrial function in vivo could be done by monitoring the oxidation reduction state of the respiratory chain. Thus, the NADH redox state of less vital organs could serve as an indicator of overall O2 imbalance as well as an endpoint of resuscitation. We have therefore tested, in a pig model, a new medical device providing real time data on NADH redox state and tissue blood flow- TBF This device contains a modified three way Foley catheter with a fiber optic probe which connects the measurement unit to the tested tissue. Female pigs underwent graded hemorrhage (GH) or Aortic clamping (AC). The main effects of GH started when blood volume decreased by 30%. At 40% blood loss, minimal levels of TBF were correlated to the maximal NADH levels. The values of the 2 parameters returned to baseline after retransfusion of the shed blood. Aortic clamping led to significant decrease in TBF while NADH levels increased. After aortic declamping the parameters recovered to normal values. Due to the short length of the urethra in female pigs and the instable contact between the probe and the tissue, inconsistency of the responses was observed. Our preliminary results show that the CritiView may be a useful tool for the detection of body O2 imbalance.

  4. A Giant Superior Mesenteric Artery Aneurysm Mimicking an Abdominal Aortic Aneurysm

    PubMed Central

    Hogendoorn, Wouter; Schlösser, Felix J.V.; Sumpio, Bauer E.

    2013-01-01

    Superior mesenteric artery aneurysms are a rare clinical finding but can present with a wide range of symptoms. They are associated with a high risk of rupture, as well as high morbidity and mortality. We present a case of a 38-year-old female who presented with acute abdominal pain and a pulsatile palpable mass in the right epigastric region without other signs or symptoms. PMID:26798672

  5. Increased Expression and Activation of Absent in Melanoma 2 Inflammasome Components in Lymphocytic Infiltrates of Abdominal Aortic Aneurysms

    PubMed Central

    Dihlmann, Susanne; Erhart, Philipp; Mehrabi, Arianeb; Nickkholgh, Arash; Lasitschka, Felix; Böckler, Dittmar; Hakimi, Maani

    2014-01-01

    Chronic vascular inflammation is a key hallmark in the pathogenesis of abdominal aortic aneurysm (AAA). Recent investigations have suggested that the inflammasome, a cytosolic multiprotein complex that recognizes pathogen-associated molecular patterns, plays a role in atherosclerosis. However, its role in AAA inflammation has not yet been investigated. This pilot study analyzed inflammasome activation and its intramural localization in 24 biopsy samples from 11 patients with asymptomatic AAA versus 12 aortic samples from apparently healthy controls. Using a histological inflammation scale, we identified grade 2/3 inflammatory changes with lymphoid aggregates/tertiary lymphoid organs in 21 out of 24 AAA samples, whereas only 7 of the 12 control samples exhibited local grade 1 inflammatory changes. Strong expression levels of “apoptosis-associated speck-like protein with a caspase recruitment domain” (ASC), caspase-1, caspase-5 and “absent in melanoma 2” (AIM2) were detected by immunohistochemistry in both sporadic infiltrating lymphoid cells and lymphoid aggregates located in the outer media and adventitia of AAA samples. In contrast, inflammasome-positive cells were restricted to cholesterol plaque–associated areas and to single infiltrating cells in control aortas. Analysis of gene expression using real-time polymerase chain reaction (PCR) revealed significantly increased median mRNA levels of the inflammasome core components PYCARD (ASC), CASP1 (Caspase-1) and IL1B (IL-1β) in AAA tissue compared with normal aorta. Moreover, significantly increased median amounts of AIM2 protein and mature caspase-5 (p20) were found in samples associated with high rupture risk compared with paired low rupture risk samples of the same AAA patient. We conclude from our data that AAA-associated lymphoid cells are capable of inflammasome signaling, suggesting that inflammasome activation is involved in the chronic inflammatory process driving AAA progression. PMID:24618883

  6. Development of a Novel Rabbit Model of Abdominal Aortic Aneurysm via a Combination of Periaortic Calcium Chloride and Elastase Incubation

    PubMed Central

    Xu, Ke; Zhang, Zhen; Qi, Xun; Xia, Yonghui; Ren, Ling

    2013-01-01

    Background The purpose of this study was to introduce a novel, simple and effective technique for creating a reliable rabbit model of abdominal aortic aneurysm (AAA) via a combination of periaortic calcium chloride (CaCl2) and elastase incubation. Methods Forty-eight New Zealand white rabbits were divided into four groups. The AAA model was developed via a 20-minute periaortic incubation of CaCl2 (0.5 mol/L) and elastase (1 Unit/µL) in a 1.5-cm aortic segment (Group CE). A single incubation of CaCl2 (Group C) or elastase (Group E) and a sham operation group (Sham Group) were used for the controls. Diameter was measured by serial digital subtraction angiography imaging on days 5, 15 and 30. Animals were sacrificed on day 5 and day 30 for histopathological and immunohistochemical studies. Results All animals in Group CE developed aneurysm, with an average dilation ratio of 65.3%±8.9% on day 5, 86.5%±28.7% on day 15 and 203.6%±39.1% on day 30. No aneurysm was found in Group C, and only one aneurysm was seen on day 5 in Group E. Group CE exhibited less intima-media thickness, endothelial recovery, elastin and smooth muscle cell (SMC) content, but stronger expression of matrix metalloproteinase-2, matrix metalloproteinase-9 and RAM11 compared to the controls. Conclusions The novel rabbit model of AAA created by using a combination of periaortic CaCl2 and elastase incubation is simple and effective to perform and is valuable for elucidating AAA mechanisms and therapeutic interventions in experimental studies. PMID:23844207

  7. Relationship between abdominal aortic and coronary artery calcification as detected by computed tomography in chronic kidney disease patients.

    PubMed

    Takayama, Yohei; Yasuda, Yoshinari; Suzuki, Susumu; Shibata, Yohei; Tatami, Yosuke; Shibata, Kanako; Niwa, Misao; Sawai, Akihiro; Morimoto, Ryota; Kato, Sawako; Ishii, Hideki; Maruyama, Shoichi; Murohara, Toyoaki

    2016-07-01

    The purpose of this study was to investigate the relationship between abdominal aortic calcification (AAC) and coronary artery calcification (CAC) in chronic kidney disease (CKD) patients. We evaluated 126 asymptomatic CKD patients (mean estimated glomerular filtration rate: 36.1 ± 14.1 mL/min/1.73 m(2), mean age 70.3 ± 10.1 years). A non-contrast computed tomography scan was used to determine the abdominal aortic calcification index (ACI) and CAC score, and this relationship was investigated. Among the subjects, AAC was present in 109 patients (86.5 %) as defined by ACI >0 and median ACI was 11.7 %. ACI increased in accordance with advances in CAC score grades (3.0, 5.2, 17.2, and 32.8 % for CAC score 0, 1-100, 101-400, and 401 or more, respectively, p < 0.001). Even after multivariate adjustment, ACI was independently associated with severe CAC score as defined by CAC score >400 [odds ratio 1.08, 95 % confidence interval (CI) 1.04-1.12, p < 0.001]. Receiver-operating curve analysis showed that the ACI optimal cut-off value predicting severe CAC score was 16.5 % (area under the curve = 0.79, 95 % CI 0.69-0.90, p < 0.001). The C statics for predicting CAC score was significantly increased by adding ACI values to the model including other risk factors (0.853 versus 0.737, p = 0.023). In conclusion, the ACI value of 16.5 % allows us to predict the presence of severe CAC in CKD patients, and that the addition of ACI to the model with traditional risk factors significantly improves the predictive ability of severe CAC score. These data reinforce the utility of ACI as a screening tool in clinical practice.

  8. Polychlorinated biphenyl 77 augments angiotensin II-induced atherosclerosis and abdominal aortic aneurysms in male apolipoprotein E deficient mice

    SciTech Connect

    Arsenescu, Violeta; Arsenescu, Razvan; Parulkar, Madhura; Karounos, Michael; Zhang, Xuan; Baker, Nicki; Cassis, Lisa A.

    2011-11-15

    Infusion of angiotensin II (AngII) to hyperlipidemic mice augments atherosclerosis and causes formation of abdominal aortic aneurysms (AAAs). Each of these AngII-induced vascular pathologies exhibit pronounced inflammation. Previous studies demonstrated that coplanar polychlorinated biphenyls (PCBs) promote inflammation in endothelial cells and adipocytes, two cell types implicated in AngII-induced vascular pathologies. The purpose of this study was to test the hypothesis that administration of PCB77 to male apolipoprotein E (ApoE) -/- mice promotes AngII-induced atherosclerosis and AAA formation. Male ApoE-/- mice were administered vehicle or PCB77 (49 mg/kg, i.p.) during week 1 and 4 (2 divided doses/week) of AngII infusion. Body weights and total serum cholesterol concentrations were not influenced by administration of PCB77. Systolic blood pressure was increased in AngII-infused mice administered PCB77 compared to vehicle (156 {+-} 6 vs 137 {+-} 5 mmHg, respectively). The percentage of aortic arch covered by atherosclerotic lesions was increased in AngII-infused mice administered PCB77 compared to vehicle (2.0 {+-} 0.4 vs 0.9 {+-} 0.1%, respectively). Lumen diameters of abdominal aortas determined by in vivo ultrasound and external diameters of excised suprarenal aortas were increased in AngII-infused mice administered PCB77 compared to vehicle. In addition, AAA incidence increased from 47 to 85% in AngII-infused mice administered PCB77. Adipose tissue in close proximity to AAAs from mice administered PCB77 exhibited increased mRNA abundance of proinflammatory cytokines and elevated expression of components of the renin-angiotensin system (angiotensinogen, angiotensin type 1a receptor (AT1aR)). These results demonstrate that PCB77 augments AngII-induced atherosclerosis and AAA formation. -- Highlights: Black-Right-Pointing-Pointer Polychlorinated biphenyl 77 (PCB77) promotes AngII-induced hypertension. Black-Right-Pointing-Pointer PCB77 augments Ang

  9. Analysis of positional candidate genes in the AAA1 susceptibility locus for abdominal aortic aneurysms on chromosome 19

    PubMed Central

    2011-01-01

    Background Abdominal aortic aneurysm (AAA) is a complex disorder with multiple genetic risk factors. Using affected relative pair linkage analysis, we previously identified an AAA susceptibility locus on chromosome 19q13. This locus has been designated as the AAA1 susceptibility locus in the Online Mendelian Inheritance in Man (OMIM) database. Methods Nine candidate genes were selected from the AAA1 locus based on their function, as well as mRNA expression levels in the aorta. A sample of 394 cases and 419 controls was genotyped for 41 SNPs located in or around the selected nine candidate genes using the Illumina GoldenGate platform. Single marker and haplotype analyses were performed. Three genes (CEBPG, PEPD and CD22) were selected for DNA sequencing based on the association study results, and exonic regions were analyzed. Immunohistochemical staining of aortic tissue sections from AAA and control individuals was carried out for the CD22 and PEPD proteins with specific antibodies. Results Several SNPs were nominally associated with AAA (p < 0.05). The SNPs with most significant p-values were located near the CCAAT enhancer binding protein (CEBPG), peptidase D (PEPD), and CD22. Haplotype analysis found a nominally associated 5-SNP haplotype in the CEBPG/PEPD locus, as well as a nominally associated 2-SNP haplotype in the CD22 locus. DNA sequencing of the coding regions revealed no variation in CEBPG. Seven sequence variants were identified in PEPD, including three not present in the NCBI SNP (dbSNP) database. Sequencing of all 14 exons of CD22 identified 20 sequence variants, five of which were in the coding region and six were in the 3'-untranslated region. Five variants were not present in dbSNP. Immunohistochemical staining for CD22 revealed protein expression in lymphocytes present in the aneurysmal aortic wall only and no detectable expression in control aorta. PEPD protein was expressed in fibroblasts and myofibroblasts in the media-adventitia border in both

  10. High Structural Stress and Presence of Intraluminal Thrombus Predict Abdominal Aortic Aneurysm 18F-FDG Uptake

    PubMed Central

    Huang, Yuan; Elkhawad, Maysoon; Tarkin, Jason M.; Joshi, Nikhil; Boyle, Jonathan R.; Buscombe, John R.; Fryer, Timothy D.; Zhang, Yongxue; Park, Ah Yeon; Wilkinson, Ian B.; Newby, David E.; Gillard, Jonathan H.

    2016-01-01

    Background— Abdominal aortic aneurysm (AAA) wall inflammation and mechanical structural stress may influence AAA expansion and lead to rupture. We hypothesized a positive correlation between structural stress and fluorine-18-labeled 2-deoxy-2-fluoro-d-glucose (18F-FDG) positron emission tomography–defined inflammation. We also explored the influence of computed tomography–derived aneurysm morphology and composition, including intraluminal thrombus, on both variables. Methods and Results— Twenty-one patients (19 males) with AAAs below surgical threshold (AAA size was 4.10±0.54 cm) underwent 18F-FDG positron emission tomography and contrast-enhanced computed tomography imaging. Structural stresses were calculated using finite element analysis. The relationship between maximum aneurysm 18F-FDG standardized uptake value within aortic wall and wall structural stress, patient clinical characteristics, aneurysm morphology, and compositions was explored using a hierarchical linear mixed-effects model. On univariate analysis, local aneurysm diameter, thrombus burden, extent of calcification, and structural stress were all associated with 18F-FDG uptake (P<0.05). AAA structural stress correlated with 18F-FDG maximum standardized uptake value (slope estimate, 0.552; P<0.0001). Multivariate linear mixed-effects analysis revealed an important interaction between structural stress and intraluminal thrombus in relation to maximum standardized uptake value (fixed effect coefficient, 1.68 [SE, 0.10]; P<0.0001). Compared with other factors, structural stress was the best predictor of inflammation (receiver-operating characteristic curve area under the curve =0.59), with higher accuracy seen in regions with high thrombus burden (area under the curve =0.80). Regions with both high thrombus burden and high structural stress had higher 18F-FDG maximum standardized uptake value compared with regions with high thrombus burdens but low stress (median [interquartile range], 1.93 [1

  11. Contrast-Enhanced Ultrasound in Detection and Follow-Up of an Infrarenal Abdominal Aortic Aneurysm with Aorto-Caval Fistula and Endovascular Treatment

    SciTech Connect

    Clevert, D.-A. Stickel, M.; Flach, P.; Strautz, T.; Horng, A.; Jauch, K. W.; Reiser, M.

    2007-06-15

    An aorto-caval fistula is a rare complication of a symptomatic or ruptured infrarenal aortic aneurysm having a frequency of 3-6%. Patients typically present with clinical signs of diffuse abdominal pain associated with increasing venous congestion and tachycardia, rapid cardiopulmonary decompensation with acute dyspnea, and an audible machinerylike bruit. Perioperative mortality is high, ranging from 20% to 60%. We report a case of an endovascular aortic repair in a patient with a symptomatic infrarenal aortic aneurysm and an aorto-caval fistula. Contrast-enhanced ultrasound seems to be a promising new diagnostic option for the diagnosis and preoperative treatment planning for patients with abdominal aortic aneurysms with rupture into the inferior vena cava. It is in addition to computed tomography angiography. It might allow a more rapid and noninvasive diagnosis, especially for patients in intensive care because of its bedside availability. Because the examination is dynamic, additional information about blood flow between the aorta and inferior cava vein can be evaluated.

  12. Automatic pose initialization for accurate 2D/3D registration applied to abdominal aortic aneurysm endovascular repair

    NASA Astrophysics Data System (ADS)

    Miao, Shun; Lucas, Joseph; Liao, Rui

    2012-02-01

    Minimally invasive abdominal aortic aneurysm (AAA) stenting can be greatly facilitated by overlaying the preoperative 3-D model of the abdominal aorta onto the intra-operative 2-D X-ray images. Accurate 2-D/3-D registration in 3-D space makes the 2-D/3-D overlay robust to the change of C-Arm angulations. By far, the 2-D/3-D registration methods based on simulated X-ray projection images using multiple image planes have been shown to be able to provide satisfactory 3-D registration accuracy. However, one drawback of the intensity-based 2-D/3-D registration methods is that the similarity measure is usually highly non-convex and hence the optimizer can easily be trapped into local minima. User interaction therefore is often needed in the initialization of the position of the 3-D model in order to get a successful 2-D/3-D registration. In this paper, a novel 3-D pose initialization technique is proposed, as an extension of our previously proposed bi-plane 2-D/3-D registration method for AAA intervention [4]. The proposed method detects vessel bifurcation points and spine centerline in both 2-D and 3-D images, and utilizes landmark information to bring the 3-D volume into a 15mm capture range. The proposed landmark detection method was validated on real dataset, and is shown to be able to provide a good initialization for 2-D/3-D registration in [4], thus making the workflow fully automatic.

  13. Semiautomatic vessel wall detection and quantification of wall thickness in computed tomography images of human abdominal aortic aneurysms

    SciTech Connect

    Shum, Judy; DiMartino, Elena S.; Goldhammer, Adam; Goldman, Daniel H.; Acker, Leah C.; Patel, Gopal; Ng, Julie H.; Martufi, Giampaolo; Finol, Ender A.

    2010-02-15

    Purpose: Quantitative measurements of wall thickness in human abdominal aortic aneurysms (AAAs) may lead to more accurate methods for the evaluation of their biomechanical environment. Methods: The authors describe an algorithm for estimating wall thickness in AAAs based on intensity histograms and neural networks involving segmentation of contrast enhanced abdominal computed tomography images. The algorithm was applied to ten ruptured and ten unruptured AAA image data sets. Two vascular surgeons manually segmented the lumen, inner wall, and outer wall of each data set and a reference standard was defined as the average of their segmentations. Reproducibility was determined by comparing the reference standard to lumen contours generated automatically by the algorithm and a commercially available software package. Repeatability was assessed by comparing the lumen, outer wall, and inner wall contours, as well as wall thickness, made by the two surgeons using the algorithm. Results: There was high correspondence between automatic and manual measurements for the lumen area (r=0.978 and r=0.996 for ruptured and unruptured aneurysms, respectively) and between vascular surgeons (r=0.987 and r=0.992 for ruptured and unruptured aneurysms, respectively). The authors' automatic algorithm showed better results when compared to the reference with an average lumen error of 3.69%, which is less than half the error between the commercially available application Simpleware and the reference (7.53%). Wall thickness measurements also showed good agreement between vascular surgeons with average coefficients of variation of 10.59% (ruptured aneurysms) and 13.02% (unruptured aneurysms). Ruptured aneurysms exhibit significantly thicker walls (1.78{+-}0.39 mm) than unruptured ones (1.48{+-}0.22 mm), p=0.044. Conclusions: While further refinement is needed to fully automate the outer wall segmentation algorithm, these preliminary results demonstrate the method's adequate reproducibility

  14. Chimney stent technique for treatment of severe abdominal aortic atherosclerotic stenosis.

    PubMed

    Ritter, Jens C; Ghosh, Jonathan; Butterfield, John S; McCollum, Charles N; Ashleigh, Raymond

    2011-03-01

    Application of the "chimney" stent technique is described in a case of complex multilevel atherosclerotic disease involving the juxtarenal aorta. A patient with significant comorbidities was unsuitable for major open reconstructive surgery. He was treated with a combined procedure consisting of chimney stent placement in the juxtarenal aorta, iliac "kissing" stent placement, and right-sided common femoral artery (CFA) replacement. This case shows that the chimney stent technique can be a feasible alternative to leaving a safety wire in the renal arteries and observation during primary angioplasty in complex atherosclerotic lesions of the abdominal aorta.

  15. Does Lower Limb Exercise Worsen Renal Artery Hemodynamics in Patients with Abdominal Aortic Aneurysm?

    PubMed Central

    Zhang, Nan; Xu, Zaipin; Deng, Xiaoyan; Liu, Ming; Liu, Xiao

    2015-01-01

    Renal artery stenosis (RAS) and renal complications emerge in some patients after endovascular aneurysm repair (EVAR) to treat abdominal aorta aneurysm (AAA). The mechanisms for the causes of these problems are not clear. We hypothesized that for EVAR patients, lower limb exercise could negatively influence the physiology of the renal artery and the renal function, by decreasing the blood flow velocity and changing the hemodynamics in the renal arteries. To evaluate this hypothesis, pre- and post-operative models of the abdominal aorta were reconstructed based on CT images. The hemodynamic environment was numerically simulated under rest and lower limb exercise conditions. The results revealed that in the renal arteries, lower limb exercise decreased the wall shear stress (WSS), increased the oscillatory shear index (OSI) and increased the relative residence time (RRT). EVAR further enhanced these effects. Because these parameters are related to artery stenosis and atherosclerosis, this preliminary study concluded that lower limb exercise may increase the potential risk of inducing renal artery stenosis and renal complications for AAA patients. This finding could help elucidate the mechanism of renal artery stenosis and renal complications after EVAR and warn us to reconsider the management and nursing care of AAA patients. PMID:25946196

  16. An integrated fluid-chemical model toward modeling the formation of intra-luminal thrombus in abdominal aortic aneurysms.

    PubMed

    Biasetti, Jacopo; Spazzini, Pier Giorgio; Swedenborg, Jesper; Gasser, T Christian

    2012-01-01

    Abdominal Aortic Aneurysms (AAAs) are frequently characterized by the presence of an Intra-Luminal Thrombus (ILT) known to influence their evolution biochemically and biomechanically. The ILT progression mechanism is still unclear and little is known regarding the impact of the chemical species transported by blood flow on this mechanism. Chemical agonists and antagonists of platelets activation, aggregation, and adhesion and the proteins involved in the coagulation cascade (CC) may play an important role in ILT development. Starting from this assumption, the evolution of chemical species involved in the CC, their relation to coherent vortical structures (VSs) and their possible effect on ILT evolution have been studied. To this end a fluid-chemical model that simulates the CC through a series of convection-diffusion-reaction (CDR) equations has been developed. The model involves plasma-phase and surface-bound enzymes and zymogens, and includes both plasma-phase and membrane-phase reactions. Blood is modeled as a non-Newtonian incompressible fluid. VSs convect thrombin in the domain and lead to the high concentration observed in the distal portion of the AAA. This finding is in line with the clinical observations showing that the thickest ILT is usually seen in the distal AAA region. The proposed model, due to its ability to couple the fluid and chemical domains, provides an integrated mechanochemical picture that potentially could help unveil mechanisms of ILT formation and development.

  17. A reduced-order model for wall shear stress in abdominal aortic aneurysms by proper orthogonal decomposition.

    PubMed

    Chang, Gary Han; Schirmer, Clemens M; Modarres-Sadeghi, Yahya

    2017-03-21

    In this paper, we introduce a method to construct a Reduced-Order Model (ROM) to study the physiological flow and the Wall Shear Stress (WSS) conditions in Abdominal Aortic Aneurysms (AAA). We start the process by running a training case using Computational Fluid Dynamics (CFD) simulations with time-varying flow parameters, such that these parameters cover the range of parameters that we would like to consider in our ROM. We use the inflow angle as the variable parameter in the current study. Then we use the snapshot Proper Orthogonal Decomposition (POD) to construct the reduced-order bases, which are subsequently enhanced using a QR-factorization technique to satisfy the relevant fluid boundary conditions. The resulting ROM enables us to study the flow pattern and the WSS distribution over a range of system parameters computationally very efficiently. We have used this method to show how the WSS varies significantly for an AAA with a simplified geometry, over a range of inflow angles usually considered mild in clinical terms. We have validated the ROM results with CFD results. This approach enables comprehensive analysis of the model system across a range of inflow angles and frequencies without the need to re-compute the simulation for small changes.

  18. Melatonin attenuates angiotensin II-induced abdominal aortic aneurysm through the down-regulation of matrix metalloproteinases.

    PubMed

    Kong, Jing; Zhang, Ya; Liu, Shanshan; Li, Hongxuan; Liu, Shangming; Wang, Jingjing; Qin, Xiaoteng; Jiang, Xiuxin; Yang, Jianmin; Zhang, Cheng; Zhang, Wencheng

    2017-02-04

    Abdominal aortic aneurysm (AAA) affects more than 5% of the population in developed countries and the pharmacotherapies for AAA are limited. Here, we explored whether melatonin regulates the development of AAA. In smooth muscle cells, melatonin treatment decreases angiotensin II-induced matrix metalloproteinase 2 (MMP2) and MMP9 expression. Human antigen R (HuR) could bind with the adenylateuridylate-rich elements of MMP2 and MMP9 mRNAs 3' untranslated region, resulting in the increased stability of MMP2 and MMP9 mRNAs. HuR is required for angiotensin II-induced MMP2 and MMP9 expression. Moreover, melatonin suppresses angiotensin II-induced HuR expression through inhibiting NF-κB signaling, leading to decreased MMP2 and MMP9 levels. Finally, melatonin attenuates the development of AAA in ApoE-/- mice infused with angiotensin II in vivo. These data support a role of HuR in the development of AAA and possible therapeutic roles for melatonin and/or HuR inhibition in AAA.

  19. In vivo assessment of cardiac metabolism and function in the abdominal aortic banding model of compensated cardiac hypertrophy

    PubMed Central

    Seymour, Anne-Marie L.; Giles, Lucia; Ball, Vicky; Miller, Jack J.; Clarke, Kieran; Carr, Carolyn A.; Tyler, Damian J.

    2015-01-01

    Aims Left ventricular hypertrophy is an adaptive response of the heart to chronic mechanical overload and can lead to functional deterioration and heart failure. Changes in cardiac energy metabolism are considered as key to the hypertrophic remodelling process. The concurrence of obesity and hypertrophy has been associated with contractile dysfunction, and this work therefore aimed to investigate the in vivo structural, functional, and metabolic remodelling that occurs in the hypertrophied heart in the setting of a high-fat, high-sucrose, Western diet (WD). Methods and results Following induction of cardiac hypertrophy through abdominal aortic banding, male Sprague Dawley rats were exposed to either a standard diet or a WD (containing 45% fat and 16% sucrose) for up to 14 weeks. Cardiac structural and functional characteristics were determined by CINE MRI, and in vivo metabolism was investigated using hyperpolarized 13C-labelled pyruvate. Cardiac hypertrophy was observed at all time points, irrespective of dietary manipulation, with no evidence of cardiac dysfunction. Pyruvate dehydrogenase flux was unchanged in the hypertrophied animals at any time point, but increased incorporation of the 13C label into lactate was observed by 9 weeks and maintained at 14 weeks, indicative of enhanced glycolysis. Conclusion Hypertrophied hearts revealed little evidence of a switch towards increased glucose oxidation but rather an uncoupling of glycolytic metabolism from glucose oxidation. This was maintained under conditions of dietary stress provided by a WD but, at this compensated phase of hypertrophy, did not result in any contractile dysfunction. PMID:25750189

  20. Surgical treatment of inflammatory abdominal aortic aneurysms: a long-term follow-up of 19 patients.

    PubMed

    Railo, Mikael; Isoluoma, Martti; Keto, Pekka; Salo, Jarmo A

    2005-05-01

    The prevalence of inflammatory abdominal aortic aneurysms (IAAA) in autopsy material ranges between 2.5 and 10% of all aneurysms. Clinical findings, the distinction between inflammatory and degenerative aneurysms, and epidemiological data are uncertain, and only a few long-term follow-up studies of patients after surgical treatment of IAAAs exist. In this study, 19 patients underwent either emergency or elective surgery for IAAA during the 10-year period between 1983 and 1993 at Helsinki University Central Hospital. Demographics, symptoms, and operative and follow-up data were collected retrospectively with emphasis on the long-term outcome of IAAA. Causes of late death were available from hospital records and the central statistical office of Finland. For survival analysis we compared ruptured versus nonruptured and emergency versus elective cases of IAAAs. Mean follow-up for the 18 surviving patients (1 hospital death) was 7.4 years. One patient (5%) died of a long-term complication of the aneurysmal disease. There was no statistically significant difference in survival rates for emergency versus elective surgery cases or ruptured versus nonruptured aneurysms. The most common cause of late death was myocardial infarction. The hospital stay mortality (5%) and morbidity (31%), and the survival rate of 26% at 5 years for ruptured and 65% and 43% for nonruptured IAAAs at 5 years and 10 years, respectively, are comparable to normal AAA survival rates. These findings show that surgery is recommended, especially as ruptures also occur in this subgroup of aneurysms.

  1. GT microsatellite repeats in the heme oxygenase-1 gene promoter associated with abdominal aortic aneurysm in Croatian patients.

    PubMed

    Gregorek, Andrea Crkvenac; Gornik, Kristina Crkvenac; Polancec, Darija Stupin; Dabelic, Sanja

    2013-06-01

    Abdominal aortic aneurysm (AAA) is a complex genetic disorder caused by the interplay of genetic and environmental risk factors. The number of (GT)(n) repeats in the heme oxygenase-1 (HO-1) gene promoter modulates transcription of this enzyme, which might have anti-inflammatory, antioxidant, antiapoptotic, and antiproliferative effect. The distribution of alleles and genotypes in Croatian individuals genotyped for the (GT)(n) HO-1 polymorphism was similar to that in other European populations. Frequency of the short (S) alleles (GT < 25) was higher in AAA patients (41.9%) than in non-AAA individuals (28.2%, p = 0.0026) because there were more SL heterozygotes among the AAA patients. The SL genotype appeared to increase the risk for AAA, but the increase was not statistically significant after adjustment for age, sex, smoking, hypertension, and hyperlipidemia (OR = 1.53, 95% CI 0.90-3.09, p = 0.062). These findings contradict those of the only other study performed so far on the association of (GT)(n) HO-1 polymorphism and AAA.

  2. The management of massive ultrafiltration distending the aneurysm sac after abdominal aortic aneurysm repair with a polytetrafluoroethylene aortobiiliac graft.

    PubMed

    Williams, G M

    1998-09-01

    Collections of serous fluid surrounding prosthetic grafts can be caused by infection or transudation of serum, and making the distinction is often troublesome. Bergamini and his colleagues developed a dog model of low-grade prosthetic graft contamination with Staphylococcus epidermatis. All animals developed evidence of graft infection, and 13 of 18 dogs developed a fluid-filled perigraft cyst. Signs of systemic infection, however, were present in only 1 animal, and the Staphylococcus epidermatis study strain was isolated from the tissue surrounding the graft in only 1 dog. The authors had to disrupt the biofilm to achieve positive cultures in 14 of 18 animals. This animal model seemed to conform to clinical experience and placed great emphasis on the role of indolent infections in the pathogenesis of perigraft fluid collection. It is equally clear that perigraft fluid collections may result from transudation of fluid through the prosthetic surfaces, which act similar to a dialysis membrane under certain circumstances. Noninfectious seromas are characterized generally by the accumulation of clear serous fluid with a protein and glucose content of serum and the lack of acute inflammatory cells when the sediment is examined. The need to distinguish between these 2 forms of fluid accumulation became important in the treatment of a 62-year-old man who was seen 2 1/2 years after the repair of an abdominal aortic aneurysm with an aortobiiliac stretch polytetrafluoroethylene (PTFE) prosthesis. There was no evidence of infection, and there was a 12 cm cystic mass surrounding a patent PTFE prosthesis.

  3. Measurement of pulsatile haemodynamic forces in a model of a bifurcated stent graft for abdominal aortic aneurysm repair.

    PubMed

    Zhou, S N; How, T V; Black, R A; Vallabhaneni, S R; McWilliams, R; Brennan, J A

    2008-05-01

    The longitudinal haemodynamic force (LF) acting on a bifurcated stent graft for abdominal aortic aneurysm repair has been estimated previously using a simple one-dimensional analytical model based on the momentum equation which assumes steady flow of an inviscid fluid. Using an instrumented stent-graft model an experimental technique was developed to measure the LF under pulsatile flow conditions. The physical stent-graft model, with main trunk diameter of 30mm and limb diameters of 12 mm, was fabricated from aluminium. Strain gauges were bonded on to the main trunk to determine the longitudinal strain which is related to the LF. After calibration, the model was placed in a pulsatile flow system with 40 per cent aqueous glycerol solution as the circulating fluid. The LF was determined using a Wheatstone bridge signal-conditioning circuit. The signals were averaged over 590 cardiac cycles and saved to a personal computer for subsequent processing. The LF was strongly dependent on the pressure but less so on the flowrate. The measured forces were higher than those predicted by the simplified mathematical model by about 6-18 per cent during the cardiac cycle. The excess measured forces are due to the viscous drag and the effect of pulsatile flow. The peak measured LF in this model of 30 mm diameter may exceed the fixation force of some current clinical endovascular stent grafts.

  4. Binding Sites for Ets Family of Transcription Factors Dominate the Promoter Regions of Differentially Expressed Genes in Abdominal Aortic Aneurysms

    PubMed Central

    Nischan, Jennifer; Gatalica, Zoran; Curtis, Mindee; Lenk, Guy M.; Tromp, Gerard; Kuivaniemi, Helena

    2011-01-01

    Background Previously, we identified 3,274 distinct differentially expressed genes in abdominal aortic aneurysm (AAA) tissue compared to non-aneurysmal controls. As transcriptional control is responsible for these expression changes, we sought to find common transcriptional elements in the promoter regions of the differentially expressed genes. Methods and Results We analyzed the up- and downregulated gene sets with Whole Genome rVISTA to determine the transcription factor binding sites (TFBSs) overrepresented in the 5 kb promoter regions of the 3,274 genes. The downregulated gene set yielded 144 TFBSs that were overrepresented in the subset when compared to the entire genome. In contrast, the upregulated gene set yielded only 13 distinct overrepresented TFBSs. Interestingly, as classified by TRANSFAC®, 8 of the 13 transcription factors (TFs) binding to these regions belong to the ETS family. Additionally, NFKB and its subunits p50 and p65 showed enrichment. Immunohistochemical analyses in 10 of the TFs from the upregulated analysis showed 9 to be present in AAA tissue. Based on Gene Ontology analysis of biological process categories of the upregulated target genes of enriched TFs, 10 TFs had enrichment in immune system process among their target genes. Conclusions Our genome-wide analysis provides further evidence of ETS and NFKB involvement in AAA. Additionally, our results provide novel insight for future studies aiming to dissect the pathogenesis of AAA and have uncovered potential therapeutic targets for AAA prevention. PMID:20031636

  5. Joint modelling of longitudinal and time-to-event data with application to predicting abdominal aortic aneurysm growth and rupture.

    PubMed

    Sweeting, Michael J; Thompson, Simon G

    2011-09-01

    Shared random effects joint models are becoming increasingly popular for investigating the relationship between longitudinal and time-to-event data. Although appealing, such complex models are computationally intensive, and quick, approximate methods may provide a reasonable alternative. In this paper, we first compare the shared random effects model with two approximate approaches: a naïve proportional hazards model with time-dependent covariate and a two-stage joint model, which uses plug-in estimates of the fitted values from a longitudinal analysis as covariates in a survival model. We show that the approximate approaches should be avoided since they can severely underestimate any association between the current underlying longitudinal value and the event hazard. We present classical and Bayesian implementations of the shared random effects model and highlight the advantages of the latter for making predictions. We then apply the models described to a study of abdominal aortic aneurysms (AAA) to investigate the association between AAA diameter and the hazard of AAA rupture. Out-of-sample predictions of future AAA growth and hazard of rupture are derived from Bayesian posterior predictive distributions, which are easily calculated within an MCMC framework. Finally, using a multivariate survival sub-model we show that underlying diameter rather than the rate of growth is the most important predictor of AAA rupture.

  6. Detection and visualization of endoleaks in CT data for monitoring of thoracic and abdominal aortic aneurysm stents

    NASA Astrophysics Data System (ADS)

    Lu, J.; Egger, J.; Wimmer, A.; Großkopf, S.; Freisleben, B.

    2008-03-01

    In this paper we present an efficient algorithm for the segmentation of the inner and outer boundary of thoratic and abdominal aortic aneurysms (TAA & AAA) in computed tomography angiography (CTA) acquisitions. The aneurysm segmentation includes two steps: first, the inner boundary is segmented based on a grey level model with two thresholds; then, an adapted active contour model approach is applied to the more complicated outer boundary segmentation, with its initialization based on the available inner boundary segmentation. An opacity image, which aims at enhancing important features while reducing spurious structures, is calculated from the CTA images and employed to guide the deformation of the model. In addition, the active contour model is extended by a constraint force that prevents intersections of the inner and outer boundary and keeps the outer boundary at a distance, given by the thrombus thickness, to the inner boundary. Based upon the segmentation results, we can measure the aneurysm size at each centerline point on the centerline orthogonal multiplanar reformatting (MPR) plane. Furthermore, a 3D TAA or AAA model is reconstructed from the set of segmented contours, and the presence of endoleaks is detected and highlighted. The implemented method has been evaluated on nine clinical CTA data sets with variations in anatomy and location of the pathology and has shown promising results.

  7. Patient-specific models of wall stress in abdominal aortic aneurysm: a comparison between MR and CT

    NASA Astrophysics Data System (ADS)

    de Putter, Sander; Breeuwer, Marcel; van de Vosse, Frans N.; Kose, Ursula; Gerritsen, Frans A.

    2006-03-01

    Finite element method based patient-specific wall stress in abdominal aortic aneurysm (AAA) may provide a more accurate rupture risk predictor than the currently used maximum transverse diameter. In this study, we have investigated the sensitivity of the wall stress in AAA with respect to geometrical variations. We have acquired MR and CT images for four patients with AAA. Three individual users have delineated the AAA vessel wall contours on the image slices. These contours were used to generate synthetic feature images for a deformable model based segmentation method. We investigated the reproducibility and the influence of the user variability on the wall stress. For sufficiently smooth models of the AAA wall, the peak wall stress is reproducible for three out of the four AAA geometries. The 0.99 percentiles of the wall stress show excellent reproducibility for all four AAAs. The variations induced by user variability are larger than the errors caused by the segmentation variability. The influence of the user variability appears to be similar for MR and CT. We conclude that the peak wall stress in AAA is sensitive to small geometrical variations. To increase reproducibility it appears to be best not to allow too much geometrical detail in the simulations. This could be achieved either by using a sufficiently smooth geometry representation or by using a more robust statistical parameter derived from the wall stress distribution.

  8. Non-Newtonian Study of Blood Flow in an Abdominal Aortic Aneurysm with a Stabilized Finite Element Method

    NASA Astrophysics Data System (ADS)

    Marrero, Victor; Sahni, Onkar; Jansen, Kenneth; Tichy, John; Taylor, Charles

    2008-11-01

    In recent years the methods of computational fluid dynamics (CFD) have been applied to the human cardiovascular system to better understand the relationship between arterial blood flow and the disease process, for example in an abdominal aortic aneurysm (AAA). Obviously, the technical challenges associated with such modeling are formidable. Among the many problems to be addressed, in this paper we add yet another complication -- the known non-Newtonian nature of blood. In this preliminary study, we used a patient-based AAA model with rigid walls. The pulsatile nature of the flow and the RCR outflow boundary condition are considered. We use the Carreau-Yasuda model to describe the non-Newtonian viscosity variation. Preliminary results for 200K, 2M, and 8M elements mesh are presented for the Newtonian and non-Newtonian cases. The broad fundamental issue we wish to eventually resolve is whether or not non-Newtonian effects in blood flow are sufficiently strong in unhealthy vessels that they must be addressed in meaningful simulations. Interesting differences during the flow cycle shed light on the problem, but further research is needed.

  9. Design and development of a decision aid to enhance shared decision making by patients with an asymptomatic abdominal aortic aneurysm

    PubMed Central

    Ubbink, Dirk T; Knops, Anouk M; Molenaar, Sjaak; Goossens, Astrid

    2008-01-01

    Objective To design, develop, and evaluate an evidence-based decision aid (DA) for patients with an asymptomatic abdominal aortic aneurysm (AAA) to inform them about the pros and cons of their treatment options (ie, surgery or watchful observation) and to help them make a shared decision. Methods A multidisciplinary team defined criteria for the desired DA as to design, medical content and functionality, particularly for elderly users. Development was according to the international standard (IPDAS). Fifteen patients with an AAA, who were either treated or not yet treated, evaluated the tool. Results A DA was developed to offer information about the disease, the risks and benefits of surgical treatment and watchful observation, and the individual possibilities and threats based on the patient’s aneurysm diameter and risk profile. The DA was improved and judged favorably by physicians and patients. Conclusion This evidence-based DA for AAA patients, developed according to IPDAS criteria, is likely to be a simple, user-friendly tool to offer patients evidence-based information about the pros and cons of treatment options for AAA, to improve patients’ understanding of the disease and treatment options, and may support decision making based on individual values. PMID:19920978

  10. Automatic identification and validation of planar collagen organization in the aorta wall with application to abdominal aortic aneurysm.

    PubMed

    Polzer, Stanislav; Gasser, T Christian; Forsell, Caroline; Druckmüllerova, Hana; Tichy, Michal; Staffa, Robert; Vlachovsky, Robert; Bursa, Jiri

    2013-12-01

    Arterial physiology relies on a delicate three-dimensional (3D) organization of cells and extracellular matrix, which is remarkably altered by vascular diseases like abdominal aortic aneurysms (AAA). The ability to explore the micro-histology of the aorta wall is important in the study of vascular pathologies and in the development of vascular constitutive models, i.e., mathematical descriptions of biomechanical properties of the wall. The present study reports and validates a fast image processing sequence capable of quantifying collagen fiber organization from histological stains. Powering and re-normalizing the histogram of the classical fast Fourier transformation (FFT) is a key step in the proposed analysis sequence. This modification introduces a powering parameter w, which was calibrated to best fit the reference data obtained using classical FFT and polarized light microscopy (PLM) of stained histological slices of AAA wall samples. The values of w = 3 and 7 give the best correlation (Pearson's correlation coefficient larger than 0.7, R 2 about 0.7) with the classical FFT approach and PLM measurements. A fast and operator independent method to identify collagen organization in the arterial wall was developed and validated. This overcomes severe limitations of currently applied methods like PLM to identify collagen organization in the arterial wall.

  11. Abdominal aortic aneurysm imaging with 3-D ultrasound: 3-D-based maximum diameter measurement and volume quantification.

    PubMed

    Long, A; Rouet, L; Debreuve, A; Ardon, R; Barbe, C; Becquemin, J P; Allaire, E

    2013-08-01

    The clinical reliability of 3-D ultrasound imaging (3-DUS) in quantification of abdominal aortic aneurysm (AAA) was evaluated. B-mode and 3-DUS images of AAAs were acquired for 42 patients. AAAs were segmented. A 3-D-based maximum diameter (Max3-D) and partial volume (Vol30) were defined and quantified. Comparisons between 2-D (Max2-D) and 3-D diameters and between orthogonal acquisitions were performed. Intra- and inter-observer reproducibility was evaluated. Intra- and inter-observer coefficients of repeatability (CRs) were less than 5.18 mm for Max3-D. Intra-observer and inter-observer CRs were respectively less than 6.16 and 8.71 mL for Vol30. The mean of normalized errors of Vol30 was around 7%. Correlation between Max2-D and Max3-D was 0.988 (p < 0.0001). Max3-D and Vol30 were not influenced by a probe rotation of 90°. Use of 3-DUS to quantify AAA is a new approach in clinical practice. The present study proposed and evaluated dedicated parameters. Their reproducibility makes the technique clinically reliable.

  12. Can Surgeons Assess CT Suitability for Endovascular Repair (EVAR) in Ruptured Abdominal Aortic Aneurysm? Implications for a Ruptured EVAR Trial

    SciTech Connect

    Rayt, Harjeet Lambert, Kelly; Bown, Matthew; Fishwick, Guy; Morgan, Robert; McCarthy, Mark; London, Nick; Sayers, Robert

    2008-09-15

    The purpose of this study was to determine whether surgeons without formal radiological training are able to assess suitability of patients with ruptured abdominal aortic aneurysms (AAA) for EVAR. The CT scans of 20 patients with AAA were reviewed under timed conditions by six vascular surgeons. Twenty minutes was allocated per scan. They were asked to determine if each aneurysm would be treatable by EVAR in the emergency setting and, if so, to measure for device selection. The results were then compared with those of a vascular radiologist. Six surgeons agreed on the suitability of endovascular repair in 45% of cases (95% CI, 23.1-68.5%; 9/20 scans; {kappa} = 0.41 [p = 0.01]) and concurred with the radiologist in eight of these. Individually, agreement ranged from 13 to 16 of the 20 scans, 65-80% between surgeons. The kappa value for agreement between all the surgeons and the radiologist was 0.47 (p = 0.01, moderate agreement). For the individual surgeons, this ranged from 0.3 to 0.6 (p = 0.01). In conclusion, while overall agreement was moderate between the surgeons and the radiologist, it is clear that if surgeons are to assess patients for ruptured EVAR in the future, focused training of surgical trainees is required.

  13. A Systematic Review of Protocols for the Three-Dimensional Morphologic Assessment of Abdominal Aortic Aneurysms Using Computed Tomographic Angiography

    SciTech Connect

    Ghatwary, Tamer M. H.; Patterson, Benjamin O.; Karthikesalingam, Alan; Hinchliffe, Robert J.; Loftus, Ian M.; Morgan, Robert; Thompson, Matt M.; Holt, Peter J. E.

    2013-02-15

    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.

  14. Duplex ultrasound and computed tomography angiography in the follow-up of endovascular abdominal aortic aneurysm repair: a comparative study*

    PubMed Central

    Cantador, Alex Aparecido; Siqueira, Daniel Emílio Dalledone; Jacobsen, Octavio Barcellos; Baracat, Jamal; Pereira, Ines Minniti Rodrigues; Menezes, Fábio Hüsemann; Guillaumon, Ana Terezinha

    2016-01-01

    Objective To compare duplex ultrasound and computed tomography (CT) angiography in terms of their performance in detecting endoleaks, as well as in determining the diameter of the aneurysm sac, in the postoperative follow-up of endovascular abdominal aortic aneurysm repair. Materials and Methods This was a prospective study involving 30 patients who had undergone endovascular repair of infrarenal aortoiliac aneurysms. Duplex ultrasound and CT angiography were performed simultaneously by independent radiologists. Measurements of the aneurysm sac diameter were assessed, and the presence or absence of endoleaks was determined. Results The average diameter of the aneurysm sac, as determined by duplex ultrasound and CT angiography was 6.09 ± 1.95 and 6.27 ± 2.16 cm, respectively. Pearson's correlation coefficient showing a statistically significant correlation (R = 0.88; p < 0.01). Comparing the duplex ultrasound and CT angiography results regarding the detection of endoleaks, we found that the former had a negative predictive value of 92.59% and a specificity of 96.15%. Conclusion Our results show that there is little variation between the two methods evaluated, and that the choice between the two would have no significant effect on clinical management. Duplex ultrasound could replace CT angiography in the postoperative follow-up of endovascular aneurysm repair of the infrarenal aorta, because it is a low-cost procedure without the potential clinical complications related to the use of iodinated contrast and exposure to radiation. PMID:27777476

  15. Systemic Pulsatile Pressure in Type II Endoleaks After Stent Grafting of Experimental Abdominal Aortic Aneurysms

    SciTech Connect

    Pitton, Michael Bernhard Schmenger, Patrick; Dueber, Christoph; Neufang, Achim; Thelen, Manfred

    2003-06-15

    Purpose: To investigate pressure and maximum rate of rise of systolic pressure (peak dP/dt) in completely excluded aneurysms and endoleaks to determine the hemodynamic impact of endoleaks. Methods: In mongrel dogs (n =36) experimental aneurysms were created by insertion of a patch (portion of rectus abdomen is muscle sheath) into the infrarenalaorta. In group I (n 18), all aortic branches of the aneurysm were ligated and all aneurysms were completely excluded by stent grafts. Group II (n = 18) consisted of aneurysms with patent aortic side branches that represented sources of endoleaks.One week (n = 12), six weeks (n = 12),and six months (n = 12) after stent grafting,hemodynamic measurements were obtained in thrombosed aneurysms and proved endoleaks. Systemic blood pressure and intraaneurysmal pressure were simultaneously measured and the respective peak dP/dt were computed. Results: At the six-month follow-up, the systolic-pressure ratio (intraaneurysmatic pressure: systemic pressure)was significantly increased in endoleaks compared to non-perfused areas(0.879 {+-} 0.042 versus 0.438 {+-} 0.176, p <0.01, group II) or completely excluded aneurysms (0.385 {+-}0.221, group I). Peak dP/dt ratio (intraaneurysmal peak dP/dt: systemic peak dP/dt) was 0.922 {+-} 0.154 in endoleaks, compared to 0.084 {+-} 0.080 in non-perfused areas (group II, p <0.01), and was 0.146 {+-} 0.121 in completely excluded aneurysms (group I). The diastolic-pressure ratio was also increased inendoleaks compared to non-perfused areas (0.929 {+-} 0.088 versus 0.655 {+-} 0.231, p < 0.01, group II) or completely excluded aneurysms (0.641 {+-} 0.278, group I). In excluded aneurysms, pressure exposure declined as the length of the follow-up period increased. Conclusion: Type II endoleaks transmit pulsatile pressure of near systemic level and indicate insufficient treatment result. In contrast, complete endovascular exclusion of aneurysms results in significantly reduced pressure exposure.

  16. The effects of aneurysm repair using an aortic prosthesis on the electrical parameters of the muscular layer of the abdominal aorta.

    PubMed

    Hauzer, W; Czerski, A; Zawadzki, W; Gnus, J; Ratajczak, K; Nowak, M; Janeczek, M; Witkiewicz, W; Niespielak, P

    2014-12-01

    The study was carried out on 10 swine of 20-30 kg body weight. Five animals were assigned to each of 2 groups. An aneurysm of the abdominal aorta was created experimentally in animals from the first and second study group. After 4 weeks, animals from the second group were subject to aneurysm repair using an aortic prosthesis. During the experiment, we measured the myoelectric activity of the muscular layer of the abdominal aorta and aneurysmal lesion with the ultrasonographic technique. Measurements of the aorta and aneurysmal lesion and histopathological analyses were carried out post-mortem. We found a statistically significant decrease in the myoelectric activity of the aorta on the aorta-straight prosthesis interface and a significant decrease in the thickness of the muscular layer of the aorta on the aorta-prosthesis interface. No similar changes were found for experimentally induced aneurysms of the abdominal aorta. A straight prosthesis graft may not be the perfect option in the treatment of abdominal aortic aneurysm, as it contributes to the remodelling of the tissue on the prosthesis-aorta interface. This may result in the relapse of an aneurysm and post-operative complications.

  17. Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

    NASA Astrophysics Data System (ADS)

    Łukasiewicz, Adam; Garkowski, Adam; Rutka, Katarzyna; Janica, Jacek; Łebkowska, Urszula

    2016-09-01

    It is hypothesized that the degree of vascularization of the thrombus may have a significant impact on the rupture of aortic aneurysms. The presence of neovascularization of the vessel wall and mural thrombus has been confirmed only in histopathological studies. However, no non-invasive imaging technique of qualitative assessment of thrombus and neovascularization has been implemented so far. Contrast-enhanced ultrasound (CEUS) has been proposed as a feasible and minimally invasive technique for in vivo visualization of neovascularization in the evaluation of tumors and atherosclerotic plaques. The aim of this study was the evaluation of mural thrombus and AAAs wall with CEUS. CEUS was performed in a group of seventeen patients with AAAs. The mural thrombus enhancement was recognized in 12 cases, yet no significant correlation between the degree of contrast enhancement and AAAs diameter, thrombus width, and thrombus echogenicity was found. We observed a rise in AAAs thrombus heterogeneity with the increase in the aneurysm diameter (r = 0.62, p = 0.017). In conclusion CEUS can visualize small channels within AAAs thrombus, which could be a result of an ongoing angiogenesis. There is a need for further research to find out whether the degree of vascularization of the thrombus may have a significant impact on the rupture of aneurysms.

  18. Abdominal aortic occlusion and vascular compromise secondary to acute gastric dilatation in a patient with bulimia.

    PubMed

    Elsharif, M; Doulias, T; Aljundi, W; Balchandra, S

    2014-11-01

    Acute gastric dilation is a rare but recognised complication in patients with bulimia and anorexia following binge episodes owing to decreased bowel motility. We present a rare case of acute gastric dilation secondary to bulimia in an otherwise healthy 18-year-old female patient that resulted in compression and complete occlusion of the abdominal aorta, leading to acute mesenteric and bilateral lower limb ischaemia. This resolved immediately following a laparotomy and gastric decompression. Management of these patients is very challenging owing to the lack of a successful precedent. To our knowledge, such a catastrophic complication has only ever been reported once in the literature and the outcome was fatal. Our case is of additional importance as it offers a successful management strategy for these patients.

  19. MRI using ultrasmall superparamagnetic particles of iron oxide in patients under surveillance for abdominal aortic aneurysms to predict rupture or surgical repair: MRI for abdominal aortic aneurysms to predict rupture or surgery—the MA3RS study

    PubMed Central

    McBride, Olivia M B; Berry, Colin; Burns, Paul; Chalmers, Roderick T A; Doyle, Barry; Forsythe, Rachael; Garden, O James; Goodman, Kirsteen; Graham, Catriona; Hoskins, Peter; Holdsworth, Richard; MacGillivray, Thomas J; McKillop, Graham; Murray, Gordon; Oatey, Katherine; Robson, Jennifer M J; Roditi, Giles; Semple, Scott; Stuart, Wesley; van Beek, Edwin J R; Vesey, Alex; Newby, David E

    2015-01-01

    Introduction Population screening for abdominal aortic aneurysms (AAA) halves the associated mortality and has led to the establishment of national screening programmes. Prediction of aneurysm growth and rupture is challenging and currently relies on serial diameter measurements with ultrasound. Recently, a novel MRI-based technique using ultrasmall superparamagnetic particles of iron oxide (USPIO) has demonstrated considerable promise as a method of identifying aneurysm inflammation and expansion. Methods and analysis The MA3RS study is a prospective observational multicentre cohort study of 350 patients with AAA in three centres across Scotland. All participants will undergo MRI with USPIO and aneurysm expansion will be measured over 2 years with CT in addition to standard clinical ultrasound surveillance. The relationship between mural USPIO uptake and subsequent clinical outcomes, including expansion, rupture and repair, will be evaluated and used to determine whether the technique augments standard risk prediction markers. To ensure adequate sensitivity to answer the primary question, we need to observe 130 events (composite of rupture or repair) with an estimated event rate of 41% over 2 years of follow-up. The MA3RS study is currently recruiting and expects to report in 2017. Discussion This is the first study to evaluate the use of USPIO-enhanced MRI to provide additional information to aid risk prediction models in patients with AAA. If successful, this study will lay the foundation for a large randomised controlled trial targeted at applying this technique to determine clinical management. Trial registration number Current Controlled Trials: ISRCTN76413758. PMID:25932334

  20. Inhibition of endoplasmic reticulum stress signaling pathway: A new mechanism of statins to suppress the development of abdominal aortic aneurysm

    PubMed Central

    Li, Yuanyuan; Lu, Gangsheng; Sun, Dating; Zuo, Houjuan; Wang, Dao Wen; Yan, Jiangtao

    2017-01-01

    Background Abdominal aortic aneurysm (AAA) is a potentially lethal disease with extremely poor survival rates once the aneurysm ruptures. Statins may exert beneficial effects on the progression of AAA. However, the underlying mechanism is still not known. The purpose of the present study is to investigate whether statin could inhibit AAA formation by inhibiting the endoplasmic reticulum (ER) stress signal pathway. Methods A clinically relevant AAA model was induced in Apolipoprotein E-deficient (ApoE−/−) mice, which were infused with angiotensin II (Ang II) for 28 days. These mice were randomly divided into following 4 groups: saline infusion alone; Ang II infusion alone; Ang II infusion plus Atorvastatin (20mg/kg/d); and Ang II infusion plus Atorvastatin (30mg/kg/d). Besides, another AAA model was induced in C57 mice with extraluminal CaCl2, which were divided into 3 groups: sham group, CaCl2-induced AAA group, and CaCl2-induced AAA plus atorvastatin (20mg/kg/d) group. Then, aortic tissue was excised for further examinations, respectively. In vitro studies, Ang II with or without simvastatin treatment were applied to the vascular smooth muscle cells (VSMCS) and Raw 264.7 cells. The ER stress signal pathway, apoptosis and inflammatory response were evaluated by in vivo and in vitro assays. Results We found that higher dose of atorvastatin can effectively suppress the development and progression of AAA induced by Ang II or CaCl2. Mechanistically, the activation of ER stress and inflammatory response were found involved in Ang II-induced AAA formation. The atorvastatin infusion significantly reduced ER stress signaling proteins, the number of apoptotic cells, and the activation of Caspase12 and Bax in the Ang II-induced ApoE−/− mice, compared with mice treated by Ang II alone. Furthermore, proinflammatory cytokines such as IL-6, IL-8, IL-1β were all remarkably inhibited after atorvastatin treatment. In vitro, the inhibitory effect of simvastatin on the ER

  1. Medium-Term Outcomes Following Endovascular Repair of Infrarenal Abdominal Aortic Aneurysms with an Unfavourable Proximal Neck

    SciTech Connect

    Saha, Prakash Hughes, John Patel, Ashish S. Donati, Tommaso Sallam, Morad Patel, Sanjay D. Bell, Rachel E.; Katsanos, Konstantinos; Modarai, Bijan Zayed, Hany A.

    2015-08-15

    PurposeThe purpose of this study was to evaluate medium-term outcomes following endovascular repair of abdominal aortic aneurysms (EVAR) with unfavourable neck anatomy using stent grafts with a 36 mm or larger proximal diameter.Materials and MethodsA retrospective review of 27 patients who underwent elective EVAR between 2006 and 2008 using a stent graft with a 36 mm or larger proximal diameter was carried out. All patients had computed tomography angiography (CTA) for procedure planning, and detailed assessment of the aneurysm neck was performed using a three-dimensional CTA workstation. Patients were followed up with CTA at 3 and 12 months and annual duplex thereafter.ResultsThe median aneurysm diameter was 7 cm, and the median aneurysm neck diameter was 31 mm. Cook Zenith stent grafts were used in all patients, with a proximal diameter of 36 mm (n = 25) and 40 mm (n = 2). Primary and assisted primary technical success rates were 74 and 93 %, respectively. The follow-up period ranged from 62 to 84 months, with a median of 72 months. 15 patients died during follow-up. Two patients died from aortic rupture, and the remaining patients died from cardiac disease (n = 4), chest sepsis (n = 6), cancer (n = 2) and renal failure (n = 1). Complications included type I endoleak (n = 5), limb occlusion (n = 2), limb stenosis (n = 2), limb kinking (n = 1), dissection of an artery (n = 1), occlusion of a femorofemoral cross-over graft (n = 1) and poor attachment of a distal limb (n = 1).ConclusionsEVAR using stent grafts in the presence of an unfavourable neck has a high risk of complications. Medium-term survival in this group is low but mainly due to patient co-morbidities.

  2. Lesson learned from early and long-term results of 327 cases of coexisting surgical abdominal diseases and aortic aneurysms treated in open and endovascular surgery.

    PubMed

    Bonardelli, Stefano; Cervi, Edoardo; Nodari, Franco; Guadrini, Cristina; Zanotti, Camilla; Giulini, Stefano Maria

    2012-06-01

    Patients with abdominal aortic aneurysm (AAA) frequently have other abdominal pathologies of surgical interest (other diseases, OD). Out of 1,375 elective open aortic replacements for AAA, 315 cases with OD were subdivided in Group 1 (82 patients with "clean wound" OD) and Group 2 (233 patients with "clean-contaminated wound" OD). The results of the sub-groups in which OD was treated at the same time as AAA were analysed (1a, 66 cases and 2a, 86 cases) and compared with OD not treated at the same time as AAA (1b, 16 cases and 2b, 147 cases). EVAR was done in 12 patients with a infrarenal AAA and concomitant abdominal disease. In this group post-operative complications occurred in two patients (endoleaks) and no sign of endograft infection was developed. Mean follow-up was 36 months. Mortality was 0% in Group 1a, 1b, 2b and 5.8% in Group 2a. In Group 1a there were one haemoperitoneum, one ischaemic colitis and one graft infection. In Group 1b there were 4 nefrectomies for renal carcinoma and three emergency hernia repairs within 18 months from AAA operation. In Group 2a the follow-up was uneventful. In Group 2b there was no acute complication of OD and 57.2% of patients were subsequently operated for OD. In the EVAR group the 30-day and late mortality rates were 0 and 25%, respectively and all deaths were cancer-related. Contemporary correction of OD in open surgery for AAA should be performed in clean wound cases, while clean-contaminated operations can be done only in selected cases. EVAR is a valid alternative technique to open vascular surgery for the concomitant treatment of aortic aneurysms and abdominal pathologies.

  3. Experimental unsteady flow study in a patient-specific abdominal aortic aneurysm model

    NASA Astrophysics Data System (ADS)

    Stamatopoulos, Ch.; Mathioulakis, D. S.; Papaharilaou, Y.; Katsamouris, A.

    2011-06-01

    The velocity field in a patient-specific abdominal aneurysm model including the aorto-iliac bifurcation was measured by 2D PIV. Phase-averaged velocities obtained in 14 planes reveal details of the flow evolution during a cycle. The aneurysm expanding asymmetrically toward the anterior side of the aorta causes the generation of a vortex at its entrance, covering the entire aneurysm bulge progressively before flow peak. The fluid entering the aneurysm impinges on the left side of its distal end, following the axis of the upstream aorta segment, causing an increased flow rate in the left (compared to the right) common iliac artery. High shear stresses appear at the aneurysm inlet and outlet as well as along the posterior wall, varying proportionally to the flow rate. At the same regions, elevated flow disturbances are observed, being intensified at flow peak and during the deceleration phase. Low shear stresses are present in the recirculation region, being two orders of magnitude smaller than the previous ones. At flow peak and during the deceleration phase, a clockwise swirling motion (viewed from the inlet) is present in the aneurysm due to the out of plane curvature of the aorta.

  4. Metabolomics with LC-QTOF-MS Permits the Prediction of Disease Stage in Aortic Abdominal Aneurysm Based on Plasma Metabolic Fingerprint

    PubMed Central

    Ciborowski, Michal; Teul, Joanna; Martin-Ventura, Jose Luis; Egido, Jesús; Barbas, Coral

    2012-01-01

    Abdominal aortic aneurysm (AAA) is a permanent and localized aortic dilation, defined as aortic diameter ≥3 cm. It is an asymptomatic but potentially fatal condition because progressive enlargement of the abdominal aorta is spontaneously evolving towards rupture. Biomarkers may help to explain pathological processes of AAA expansion, and allow us to find novel therapeutic strategies or to determine the efficiency of current therapies. Metabolomics seems to be a good approach to find biomarkers of AAA. In this study, plasma samples of patients with large AAA, small AAA, and controls were fingerprinted with LC-QTOF-MS. Statistical analysis was used to compare metabolic fingerprints and select metabolites that showed a significant change. Results presented here reveal that LC-QTOF-MS based fingerprinting of plasma from AAA patients is a very good technique to distinguish small AAA, large AAA, and controls. With the use of validated PLS-DA models it was possible to classify patients according to the disease stage and predict properly the stage of additional AAA patients. Identified metabolites indicate a role for sphingolipids, lysophospholipids, cholesterol metabolites, and acylcarnitines in the development and progression of AAA. Moreover, guanidinosuccinic acid, which mimics nitric oxide in terms of its vasodilatory action, was found as a strong marker of large AAA. PMID:22384120

  5. Cell-Activation by Shear Stresses in Abdominal Aortic Aneurysms (AAA)

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Sparks, Steven; Chomaz, Jean-Marc; Lasheras, Juan C.

    2003-11-01

    Increasing experimental evidence indicates that low and oscillatory shear stresses promote proliferative, thrombotic, adhesive and inflammatory-mediated degenerative conditions throughout the wall of the aorta. These degenerative conditions have been shown to be involved in the pathogenesis of AAAs, a permanent, localized dilatation of the abdominal aorta. The purpose of this study is to measure both the magnitude and the duration of the shear stresses acting on both the arterial walls and on the blood cells inside AAAs, and to characterize their changes as the AAA enlarges. We conducted a parametric in-vitro study of the pulsatile blood flow in elastic models of AAAs while systematically varying the blood flow parameters, and the geometry of the aneurysm's bulging. The instantaneous flow characteristic inside the AAA was measured using DPIV at a sampling rate of 15 Hertz. A "cell-activation parameter" defined as the integral of the product of the magnitude of the shear stress and the time during which the stress acts was computed along each of the blood cell pathlines. The Lagrangian tracking of the blood cells shows that a large majority of them are subjected first to very high level of shear-induced "cell-activation" while later on they are entrained in regions of stasis where their residence time can increase up to several cardiac cycles. This cell-activation followed by the entrainment in low shear regions creates the optimal cell-adhesive and inflammatory-mediated degenerative conditions that are postulated to play an important role in the etiology and progressive enlargement of AAAs.

  6. Inhibition of Receptor-Interacting Protein Kinase 1 with Necrostatin–1s ameliorates disease progression in elastase-induced mouse abdominal aortic aneurysm model

    PubMed Central

    Wang, Qiwei; Zhou, Ting; Liu, Zhenjie; Ren, Jun; Phan, Noel; Gupta, Kartik; Stewart, Danielle M.; Morgan, Stephanie; Assa, Carmel; Kent, K. Craig; Liu, Bo

    2017-01-01

    Abdominal aortic aneurysm (AAA) is a common aortic disease with a progressive nature. There is no approved pharmacological treatment to effectively slow aneurysm growth or prevent rupture. Necroptosis is a form of programmed necrosis that is regulated by receptor-interacting protein kinases (RIPs). We have recently demonstrated that the lack of RIP3 in mice prevented aneurysm formation. The goal of the current study is to test whether perturbing necroptosis affects progression of existing aneurysm using the RIP1 inhibitors Necrostatin-1 (Nec-1) and an optimized form of Nec-1, 7-Cl-O-Nec-1 (Nec-1s). Seven days after aneurysm induction by elastase perfusion, mice were randomly administered DMSO, Nec-1 (3.2 mg/kg/day) and Nec-1s (1.6 mg/kg/day) via intraperitoneal injection. Upon sacrifice on day 14 postaneurysm induction, the aortic expansion in the Nec-1s group (64.12 ± 4.80%) was significantly smaller than that of the DMSO group (172.80 ± 13.68%) (P < 0.05). The mean aortic diameter of Nec-1 treated mice appeared to be smaller (121.60 ± 10.40%) than the DMSO group, though the difference was not statistically significant (P = 0.1). Histologically, the aortic structure of Nec-1s-treated mice appeared normal, with continuous and organized elastin laminae and abundant αActin-expressing SMCs. Moreover, Nect-1s treatment diminished macrophage infiltration and MMP9 accumulation and increased aortic levels of tropoelastin and lysyl oxidase. Together, our data suggest that pharmacological inhibition of necroptosis with Nec-1s stabilizes pre-existing aneurysms by diminishing inflammation and promoting connective tissue repair. PMID:28186202

  7. Inhibition of Receptor-Interacting Protein Kinase 1 with Necrostatin-1s ameliorates disease progression in elastase-induced mouse abdominal aortic aneurysm model.

    PubMed

    Wang, Qiwei; Zhou, Ting; Liu, Zhenjie; Ren, Jun; Phan, Noel; Gupta, Kartik; Stewart, Danielle M; Morgan, Stephanie; Assa, Carmel; Kent, K Craig; Liu, Bo

    2017-02-10

    Abdominal aortic aneurysm (AAA) is a common aortic disease with a progressive nature. There is no approved pharmacological treatment to effectively slow aneurysm growth or prevent rupture. Necroptosis is a form of programmed necrosis that is regulated by receptor-interacting protein kinases (RIPs). We have recently demonstrated that the lack of RIP3 in mice prevented aneurysm formation. The goal of the current study is to test whether perturbing necroptosis affects progression of existing aneurysm using the RIP1 inhibitors Necrostatin-1 (Nec-1) and an optimized form of Nec-1, 7-Cl-O-Nec-1 (Nec-1s). Seven days after aneurysm induction by elastase perfusion, mice were randomly administered DMSO, Nec-1 (3.2 mg/kg/day) and Nec-1s (1.6 mg/kg/day) via intraperitoneal injection. Upon sacrifice on day 14 postaneurysm induction, the aortic expansion in the Nec-1s group (64.12 ± 4.80%) was significantly smaller than that of the DMSO group (172.80 ± 13.68%) (P < 0.05). The mean aortic diameter of Nec-1 treated mice appeared to be smaller (121.60 ± 10.40%) than the DMSO group, though the difference was not statistically significant (P = 0.1). Histologically, the aortic structure of Nec-1s-treated mice appeared normal, with continuous and organized elastin laminae and abundant αActin-expressing SMCs. Moreover, Nect-1s treatment diminished macrophage infiltration and MMP9 accumulation and increased aortic levels of tropoelastin and lysyl oxidase. Together, our data suggest that pharmacological inhibition of necroptosis with Nec-1s stabilizes pre-existing aneurysms by diminishing inflammation and promoting connective tissue repair.

  8. Periods of low atmospheric pressure are associated with high abdominal aortic aneurysm rupture rates in Northern Ireland.

    PubMed Central

    Harkin, D. W.; O'Donnell, M.; Butler, J.; Blair, P. H.; Hood, J. M.; Barros D'Sa, A. A. B.

    2005-01-01

    Seasonal and circadian variation in the incidence of ruptured abdominal aortic aneurysm (RAAA) has been reported. We explored the role of atmospheric pressure changes on rupture incidence and its relationship to cardiovascular risk factors. During a three year-period, 1st April 1998 and 31st March 2001, data was prospectively acquired on 144 Ruptured Abdominal Aortic Aneurysm (RAAA) presenting to the Regional Vascular Surgery Unit at the Royal Victoria Hospital, Belfast, Northern Ireland. For each patient the chronology of acute onset of symptoms and presentation to the regional vascular unit was recorded, along with details of standard cardiovascular risk factors. During the same period meteorological data including atmospheric pressure and air temperature were recorded daily at the regional meteorological research unit, Armagh. We then analyzed the monthly mean values for daily rupture incidence in relation to the monthly values for atmospheric pressure, pressure change and temperature. Furthermore atmospheric pressure on the day of rupture, and day preceding rupture, were also analyzed in relation to days without rupture presentation and between individual ruptures for various cardiovascular risk factors. Data demonstrated a significant monthly variation in aneurysm rupture frequency, (p<0.03, ANOVA). There was also a significant monthly variation in mean barometric atmospheric pressure, (p<0.0001, ANOVA), months with high rupture frequency also exhibiting low average pressures in the months of April (0.24 +/- 0.04 ruptures per day and 1007.78 +/- 1.23 mB) and September (0.16 +/- 0.04 ruptures per day and 1007.12 +/- 1.14 mB), respectively. The average barometric pressures were found to be significantly lower on those days when ruptures occurred (n=1127) compared to days when ruptures did not occur (n=969 days), (1009.98 +/- 1.11 versus 1012.09 +/- 0.41, p<0.05). Full data on risk factors was available on 103 of the 144 rupture patients and was further analyzed

  9. Identification of key genes associated with the human abdominal aortic aneurysm based on the gene expression profile

    PubMed Central

    CHEN, XUDONG; ZHENG, CHENGFEI; HE, YUNJUN; TIAN, LU; LI, JIANHUI; LI, DONGLIN; JIN, WEI; LI, MING; ZHENG, SHUSEN

    2015-01-01

    The present study was aimed at screening the key genes associated with abdominal aortic aneurysm (AAA) in the neck, and to investigate the molecular mechanism underlying the development of AAA. The gene expression profile, GSE47472, including 14 AAA neck samples and eight donor controls, was downloaded from the Gene Expression Omnibus database. The total AAA samples were grouped into two types to avoid bias. Differentially expressed genes (DEGs) were screened in patients with AAA and subsequently compared with donor controls using linear models for microarray data, or the Limma package in R, followed by gene ontology enrichment analysis. Furthermore, a protein-protein interaction (PPI) network based on the DEGs was constructed to detect highly connected regions using a Cytoscape plugin. In total, 388 DEGs in the AAA samples were identified. These DEGs were predominantly associated with limb development, including embryonic limb development and appendage development. Nuclear receptor co-repressor 1 (NCOR1), histone 4 (H4), E2F transcription factor 4 (E2F4) and hepatocyte nuclear factor 4α (HNF4A) were the four transcription factors associated with AAA. Furthermore, HNF4A indirectly interacted with the other three transcription factors. Additionally, six clusters were selected from the PPI network. The DEG screening process and the construction of an interaction network enabled an understanding of the mechanism of AAA to be gleaned. HNF4A may exert an important role in AAA development through its interactions with the three other transcription factors (E2F4, NCOR1 and H4), and the mechanism of this coordinated regulation of the transcription factors in AAA may provide a suitable target for the development of therapeutic intervention strategies. PMID:26498477

  10. Genetic variants associated with type 2 diabetes and adiposity and risk of intracranial and abdominal aortic aneurysms.

    PubMed

    van 't Hof, Femke Ng; Vaucher, Julien; Holmes, Michael V; de Wilde, Arno; Baas, Annette F; Blankensteijn, Jan D; Hofman, Albert; Kiemeney, Lambertus Alm; Rivadeneira, Fernando; Uitterlinden, André G; Vermeulen, Sita H; Rinkel, Gabriël Je; de Bakker, Paul Iw; Ruigrok, Ynte M

    2017-04-05

    Epidemiological studies show that type 2 diabetes (T2D) is inversely associated with intracranial aneurysms (IA) and abdominal aortic aneurysms (AAA). Although adiposity has not been considered a risk factor for IA, there have been inconsistent reports relating adiposity to AAA risk. We assessed whether these observations have a genetic, causal basis. To this end, we extracted genotypes of validated single-nucleotide polymorphisms associated with T2D (n=65), body mass index (BMI) (n=97) and waist-hip ratio adjusted for BMI (WHRadjBMI) (n=47) from genotype data collected in 717 IA cases and 1988 controls, and in 818 AAA cases and 3004 controls, all of Dutch descent. For each of these three traits, we computed genetic risk scores (GRS) for each individual in these case-control data sets by summing the number of risk alleles weighted by their published effect size, and tested whether these GRS were associated with risk of aneurysm. We divided the cohorts into GRS quartiles, and compared IA and AAA risk in the highest with the lowest GRS quartile using logistic regression. We found no evidence for association in IA or AAA risk between top and bottom quartiles for the genetic risk scores for T2D, BMI and WHRadjBMI. However, additional Mendelian randomization analyses suggested a trend to potentially causal associations between BMI and WHRadjBMI and risk of AAA. Overall, our results do not support epidemiological observations relating T2D to aneurysm risk, but may indicate a potential role of adiposity in AAA that requires further investigation.European Journal of Human Genetics advance online publication, 5 April 2017; doi:10.1038/ejhg.2017.48.

  11. Meteorology in ruptured abdominal aortic aneurysm: an institutional study and a meta-analysis of published studies reporting atmospheric pressure.

    PubMed

    Takagi, H; Watanabe, T; Mizuno, Y; Kawai, N; Umemoto, T

    2014-12-01

    The aim of this paper was to determine whether weather factors including atmospheric pressure are associated with the occurrence of ruptured abdominal aortic aneurysm (RAAA). We investigated our institutional experiences of RAAA in more than 150 patients during 8 years. Further, we performed a meta-analysis of published studies reporting the influence of atmospheric pressure on RAAA. We retrospectively evaluated 152 patients who underwent surgery for RAAA (including ruptured iliac arterial aneurysm) at our institute between 1 January 2006 and 31 December 2013. Daily regional meteorological data (in the nearest weather station located 3.5 km from the hospital) were obtained online from Japan Meteorological Agency. To identify comparative studies of mean atmospheric pressure on the day with RAAA versus that on the day without RAAA, MEDLINE and EMBASE were searched through January 2014 using Web-based search engines (PubMed and OVID). Mean sea level atmospheric pressure, delta mean atmospheric pressure (difference between mean sea level atmospheric pressure on the day and that on the previous day), and sunshine duration on the day with RAAA were significantly lower than those on the day without RAAA: 1012.43±7.44 versus 1013.71±6.49 hPa, P=0.039, -1.18±5.15 versus 0.05±5.62 hPa, P=0.005; and 4.76±3.76 versus 5.47±3.88 h, P=0.026; respectively. A pooled analysis of 8 studies (including our institutional study) demonstrated that mean atmospheric pressure on the day with RAAA was significantly lower than that on the day without RAAA: standardized mean difference, -0.09; 95% confidence interval, -0.14 to -0.04; P=0.0009. Atmospheric pressure on the day with RAAA appears lower than that on the day without RAAA. Atmospheric pressure may be associated with the occurrence of RAAA.

  12. The quasi-static failure properties of the abdominal aortic aneurysm wall estimated by a mixed experimental-numerical approach.

    PubMed

    Forsell, Caroline; Swedenborg, Jesper; Roy, Joy; Gasser, T Christian

    2013-07-01

    Assessing the risk for abdominal aortic aneurysm (AAA) rupture is critical in the management of aneurysm patients and an individual assessment is possible with the biomechanical rupture risk assessment. Such an assessment could potentially be improved by a constitutive AAA wall model that accounts for irreversible damage-related deformations. Because of that the present study estimated the elastic and inelastic properties of the AAA wall through a mixed experimental-numerical approach. Specifically, finite element (FE) models of bone-shaped tensile specimens were used to merge data from failure testing of the AAA wall with their measured collagen orientation distribution. A histo-mechanical constitutive model for collagen fibers was employed, where plastic fibril sliding determined not only remaining deformations but also weakening of the fiber. The developed FE models were able to replicate the experimentally recorded load-displacement property of all 16 AAA wall specimens that were investigated in the study. Tensile testing in longitudinal direction of the AAA defined a Cauchy strength of 569(SD 411) kPa that was reached at a stretch of 1.436(SD 0.118). The stiffness and strength of specimens decreased with the wall thickness and were elevated (p = 0.018; p = 0.030) in patients with chronic obstructive pulmonary disease (COPD). Smoking affected the tissue parameters that were related to the irreversible deformation response, and no correlation with gender and age was found. The observed effects on the biomechanical properties of the AAA wall could have long-term consequences for the management of aneurysm patients, i.e., specifically they might influence future AAA rupture risk assessments. However, in order to design appropriate clinical validation studies our findings should firstly be verified in a larger patient cohort.

  13. Risk Factors for Survival following Open Surgical Repair of Ruptured Abdominal Aortic Aneurysms: A 13-Year Experience

    PubMed Central

    Ozen, Anil; Hanedan, Muhammet Onur; Songur, Çetin Murat; Boysan, Emre; Unal, Ertekin Utku; Mola, Serkan; Erkengel, Halil Ibrahim; Kubat, Emre; Iscan, Zafer; Tutun, Ufuk; Sarıtas, Ahmet; Birincioglu, Cemal Levent

    2015-01-01

    Background: Surgical treatment of a ruptured abdominal aorta aneurysm (RAAA) continues to present a significant challenge to surgeons. There are some patient factors such as age and gender that cannot be changed, and comorbid conditions can be optimized but not eliminated. The purpose of this study was to identify the risk factors affecting high mortality after the surgical repair of an RAAA. Methods: Data on 121 patients who underwent surgical repair for RAAAs between January 1997 and June 2011 in our institution were collected retrospectively. All the patients had been diagnosed by computed tomography (CT) scans, and intraoperative extra-luminal blood was visualized intraoperatively. Variables studied comprised demographic data; preoperative, operative, and postoperative data; and the causes of mortality. Multivariate regression analysis was used to determine the predictors of mortality. Results: One hundred eight (89.2%) patients were male and 13 (10.7%) were female at an average age of 68.9 ± 10.5 years. Totally, 121 patients underwent surgery for RAAAs. Fifty-four patients had aortic tube grafts, 32 aortobiiliac grafts, 20 aortobifemoral grafts, 1 aortoiliac graft, and 1 aortofemoral graft for the replacement of the RAAAs. Seven patients had only surgical exploration. Operative mortality was 41.3% (50 patients). The factors associated with mortality were preoperative shock, free blood, positive inotropic agent, hematocrit value, and need for blood and plasma. In the multivariate analysis, preoperative shock and positive inotropic agents were found to be significant as the predictors of death (OR: 19.8, 95%CI: 3.2-122.8 and OR: 8.6, 95% CI: 2.9-26.3, respectively). Conclusion: This study revealed that the preoperative clinical findings affected the mortality associated with RAAAs. PMID:26697083

  14. FSI Simulations of Pulse Wave Propagation in Human Abdominal Aortic Aneurysm: The Effects of Sac Geometry and Stiffness

    PubMed Central

    Li, Han; Lin, Kexin; Shahmirzadi, Danial

    2016-01-01

    This study aims to quantify the effects of geometry and stiffness of aneurysms on the pulse wave velocity (PWV) and propagation in fluid–solid interaction (FSI) simulations of arterial pulsatile flow. Spatiotemporal maps of both the wall displacement and fluid velocity were generated in order to obtain the pulse wave propagation through fluid and solid media, and to examine the interactions between the two waves. The results indicate that the presence of abdominal aortic aneurysm (AAA) sac and variations in the sac modulus affect the propagation of the pulse waves both qualitatively (eg, patterns of change of forward and reflective waves) and quantitatively (eg, decreasing of PWV within the sac and its increase beyond the sac as the sac stiffness increases). The sac region is particularly identified on the spatiotemporal maps with a region of disruption in the wave propagation with multiple short-traveling forward/reflected waves, which is caused by the change in boundary conditions within the saccular region. The change in sac stiffness, however, is more pronounced on the wall displacement spatiotemporal maps compared to those of fluid velocity. We conclude that the existence of the sac can be identified based on the solid and fluid pulse waves, while the sac properties can also be estimated. This study demonstrates the initial findings in numerical simulations of FSI dynamics during arterial pulsations that can be used as reference for experimental and in vivo studies. Future studies are needed to demonstrate the feasibility of the method in identifying very mild sacs, which cannot be detected from medical imaging, where the material property degradation exists under early disease initiation. PMID:27478394

  15. Prevalence of abdominal aortic calcifications in older living renal donors and its effect on graft function and histology.

    PubMed

    Wu, En-Haw; Wojciechowski, David; Chandran, Sindhu; Yeh, Benjamin M; Park, Meyeon; Westphalen, Antonio; Wang, Zhen J

    2015-10-01

    We assessed the prevalence of abdominal aortic calcification (AAC) in older living kidney donors and its effect on recipient eGFR and graft histology. A total of 292 consecutive living pairs with donor age ≥50 from 2003 to 2013 were identified (mean age 56; range 50-78; F/M: 1.8). Donor AAC was determined by prenephrectomy unenhanced CT. Recipient eGFR and spot urine protein: creatinine ratios (UPCRs) were recorded. A total of 180 recipients had 6-month protocol biopsies. AAC was present in 40.7% of donors, and they were older (58.6 versus 54.7 years old, P < 0.0001) and more likely to be male (77.6% vs. 37.3%, P = 0.004). There was no significant difference in eGFR or spot UPCR up to 36 months in recipients of allografts from donors with versus without AAC. At 6-month biopsy, there was a higher percentage of allografts with vascular fibrous intimal thickening and arteriolar hyaline thickening from donors with versus without AAC (vascular fibrous intimal thickening: 38.8% vs. 7.1% and arteriolar hyaline thickening: 35.8% vs. 7.1%; P < 0.001 for both). The presence of donor AAC predicts the presence of vascular disease [vascular fibrous intimal thickening (OR: 7.2; CI:2.9-17.9) and arteriolar hyaline thickening (OR:5.7; CI:2.3-14.1)] in allografts at 6 months. Donor AAC is predictive of renal vascular disease and may help to improve the screening of potential donors and inform post-transplant management.

  16. A numerical implementation to predict residual strains from the homogeneous stress hypothesis with application to abdominal aortic aneurysms.

    PubMed

    Polzer, Stanislav; Bursa, Jiri; Gasser, T Christian; Staffa, Robert; Vlachovsky, Robert

    2013-07-01

    Wall stress analysis of abdominal aortic aneurysm (AAA) is a promising method of identifying AAAs at high risk of rupture. However, neglecting residual strains (RS) in the load-free configuration of patient-specific finite element analysis models is a sever limitation that strongly affects the computed wall stresses. Although several methods for including RS have been proposed, they cannot be directly applied to patient-specific AAA simulations. RS in the AAA wall are predicted through volumetric tissue growth that aims at satisfying the homogeneous stress hypothesis at mean arterial pressure load. Tissue growth is interpolated linearly across the wall thickness and aneurysm tissues are described by isotropic constitutive formulations. The total deformation is multiplicatively split into elastic and growth contributions, and a staggered schema is used to solve the field variables. The algorithm is validated qualitatively at a cylindrical artery model and then applied to patient-specific AAAs (n = 5). The induced RS state is fully three-dimensional and in qualitative agreement with experimental observations, i.e., wall strips that were excised from the load-free wall showed stress-releasing-deformations that are typically seen in laboratory experiments. Compared to RS-free simulations, the proposed algorithm reduced the von Mises stress gradient across the wall by a tenfold. Accounting for RS leads to homogenized wall stresses, which apart from reducing the peak wall stress (PWS) also shifted its location in some cases. The present study demonstrated that the homogeneous stress hypothesis can be effectively used to predict RS in the load-free configuration of the vascular wall. The proposed algorithm leads to a fast and robust prediction of RS, which is fully capable for a patient-specific AAA rupture risk assessment. Neglecting RS leads to non-realistic wall stress values that severely overestimate the PWS.

  17. Caveolin-1 is critical for abdominal aortic aneurysm formation induced by angiotensin II and inhibition of lysyl oxidase

    PubMed Central

    Takayanagi, Takehiko; Crawford, Kevin J.; Kobayashi, Tomonori; Obama, Takashi; Tsuji, Toshiyuki; Elliott, Katherine J.; Hashimoto, Tomoki; Rizzo, Victor; Eguchi, Satoru

    2014-01-01

    Although angiotensin II (Ang II) and its receptor AT1 have been implicated in abdominal aortic aneurysm (AAA) formation, the proximal signaling events primarily responsible for AAA formation remain uncertain. Caveolae are cholesterol-rich membrane microdomains that serve as a signaling platform to facilitate the temporal and spatial localization of signal transduction events including those stimulated by Ang II. Caveolin-1 (Cav1) enriched caveolae in vascular smooth muscle cells mediate ADAM17-dependent epidermal growth factor receptor (EGFR) transactivation, which is linked to vascular remodeling induced by Ang II. Here, we have tested our hypothesis that Cav1 plays a critical role for development of AAA at least in part via its specific alteration of Ang II signaling within caveolae. Cav1−/− mice and the control wild-type mice were co-infused with Ang II and β-aminopropionitrile to induce AAA. We found that Cav1−/− mice with the co-infusion did not develop AAA compared to control mice in spite of hypertension. We found an increased expression of ADAM17 and enhanced phosphorylation of EGFR in AAA. These events were markedly attenuated in Cav1−/− aortae with the co-infusion. Furthermore, Cav1−/− mice aortae with the co-infusion showed less endoplasmic reticulum stress, oxidative stress and inflammatory responses compared to aortae from control mice. Cav1 silencing in cultured vascular smooth muscle cells prevented Ang II-induced ADAM17 induction and activation. In conclusion, Cav1 appears to play a critical role in the formation of AAA and associated endoplasmic reticulum/oxidative stress presumably through the regulation of caveolae compartmentalized signals induced by Ang II. PMID:24329494

  18. Prior Distributions of Material Parameters for Bayesian Calibration of Growth and Remodeling Computational Model of Abdominal Aortic Wall.

    PubMed

    Seyedsalehi, Sajjad; Zhang, Liangliang; Choi, Jongeun; Baek, Seungik

    2015-10-01

    For the accurate prediction of the vascular disease progression, there is a crucial need for developing a systematic tool aimed toward patient-specific modeling. Considering the interpatient variations, a prior distribution of model parameters has a strong influence on computational results for arterial mechanics. One crucial step toward patient-specific computational modeling is to identify parameters of prior distributions that reflect existing knowledge. In this paper, we present a new systematic method to estimate the prior distribution for the parameters of a constrained mixture model using previous biaxial tests of healthy abdominal aortas (AAs). We investigate the correlation between the estimated parameters for each constituent and the patient's age and gender; however, the results indicate that the parameters are correlated with age only. The parameters are classified into two groups: Group-I in which the parameters ce, ck1, ck2, cm2,Ghc, and ϕe are correlated with age, and Group-II in which the parameters cm1, Ghm, G1e, G2e, and α are not correlated with age. For the parameters in Group-I, we used regression associated with age via linear or inverse relations, in which their prior distributions provide conditional distributions with confidence intervals. For Group-II, the parameter estimated values were subjected to multiple transformations and chosen if the transformed data had a better fit to the normal distribution than the original. This information improves the prior distribution of a subject-specific model by specifying parameters that are correlated with age and their transformed distributions. Therefore, this study is a necessary first step in our group's approach toward a Bayesian calibration of an aortic model. The results from this study will be used as the prior information necessary for the initialization of Bayesian calibration of a computational model for future applications.

  19. Comparative effect of propofol versus sevoflurane on renal ischemia/reperfusion injury after elective open abdominal aortic aneurysm repair

    PubMed Central

    Ammar, AS; Mahmoud, KM

    2016-01-01

    Background: Renal injury is a common cause of morbidity and mortality after elective abdominal aortic aneurysm (AAA) repair. Propofol has been reported to protect several organs from ischemia/reperfusion (I/R) induced injury. We performed a randomized clinical trial to compare propofol and sevoflurane for their effects on renal I/R injury in patients undergoing elective AAA repair. Materials and Methods: Fifty patients scheduled for elective AAA repair were randomized to receive propofol anesthesia in group I or sevoflurane anesthesia in group II. Urinary specific kidney proteins (N-acetyl-beta-glucosamidase, alpha-1-microglobulin, glutathione transferase [GST]-pi, GST-alpha) were measured within 5 min of starting anesthesia as a base line (T0), at the end of surgery (T1), 8 h after surgery (T2), 16 h after surgery (T3), and 24 h postoperatively (T4). Serum pro-inflammatory cytokines (tumor necrosis factor-α and interleukin 1-β) were measured at the same time points. In addition, serum creatinine and cystatin C were measured before starting surgery as a baseline and at days 1, 3, and 6 after surgery. Results: Postoperative urinary concentrations of all measured kidney specific proteins and serum pro-inflammatory cytokines were significantly lower in the propofol group. In addition, the serum creatinine and cystatin C were significantly lower in the propofol group compared with the sevoflurane group. Conclusion: Propofol significantly reduced renal injury after elective open AAA repair and this could have clinical implications in situations of expected renal I/R injury. PMID:27375385

  20. Population-Based Study of Incidence of Acute Abdominal Aortic Aneurysms With Projected Impact of Screening Strategy

    PubMed Central

    Howard, Dominic P J; Banerjee, Amitava; Fairhead, Jack F; Handa, Ashok; Silver, Louise E; Rothwell, Peter M

    2015-01-01

    Background Current abdominal aortic aneurysm (AAA) screening in men age 65 might have limited impact on overall AAA death rates if incidence is moving to older ages. Up-to-date population-based studies of age-specific incidence, risk factors, and outcome of acute AAA are needed to inform screening policy. Methods and Results In a prospective, population-based study (Oxfordshire, UK, 2002–2014), the incidence and outcome of acute AAA events were determined. Based on population projections and current incidence trends, the impact of screening strategies in the UK was estimated. Over the 12-year period, 103 incident acute AAA events occurred in the study population of 92 728. Incidence/100 000/year was 55 in men ages 65 to 74 years, but increased to 112 at 75 to 85 and 298 at ≥85, with 66.0% of all events occurring at age ≥75 years. Incidence at ages 65 to 74 was highest in male smokers (274), with 96.4% of events in men <75 years occurring in ever-smokers. Extrapolating rates to the UK population, using trial evidence of screening efficacy, the current UK screening program would prevent 5.6% of aneurysm-related deaths (315 200 scans/year: 1426/death prevented, 121/year-of-life saved). Screening only male smokers age 65 and then all men at age 75 would prevent 21.1% of deaths (247 900 scans/year; 297/death prevented, 34/year-of-life saved). By 2030, 91.0% of deaths will occur at age ≥75, 61.6% at ≥85, and 28.6% in women. Conclusions Given that two thirds of acute AAA occurred at ≥75 years of age, screening older age groups should be considered. Screening nonsmokers at age 65 is likely to have very little impact on AAA event rates. PMID:26289347

  1. An hybrid CPU-GPU framework for quantitative follow-up of abdominal aortic aneurysm volume by CT angiography

    NASA Astrophysics Data System (ADS)

    Kauffmann, Claude; Tang, An; Therasse, Eric; Soulez, Gilles

    2010-03-01

    We developed a hybrid CPU-GPU framework enabling semi-automated segmentation of abdominal aortic aneurysm (AAA) on Computed Tomography Angiography (CTA) examinations. AAA maximal diameter (D-max) and volume measurements and their progression between 2 examinations can be generated by this software improving patient followup. In order to improve the workflow efficiency some segmentation tasks were implemented and executed on the graphics processing unit (GPU). A GPU based algorithm is used to automatically segment the lumen of the aneurysm within short computing time. In a second step, the user interacted with the software to validate the boundaries of the intra-luminal thrombus (ILT) on GPU-based curved image reformation. Automatic computation of D-max and volume were performed on the 3D AAA model. Clinical validation was conducted on 34 patients having 2 consecutive MDCT examinations within a minimum interval of 6 months. The AAA segmentation was performed twice by a experienced radiologist (reference standard) and once by 3 unsupervised technologists on all 68 MDCT. The ICC for intra-observer reproducibility was 0.992 (>=0.987) for D-max and 0.998 (>=0.994) for volume measurement. The ICC for inter-observer reproducibility was 0.985 (0.977-0.90) for D-max and 0.998 (0.996- 0.999) for volume measurement. Semi-automated AAA segmentation for volume follow-up was more than twice as sensitive than D-max follow-up, while providing an equivalent reproducibility.

  2. Clonal expansion of T cells in abdominal aortic aneurysm: a role for doxycycline as drug of choice?

    PubMed

    Kroon, Albert M; Taanman, Jan-Willem

    2015-05-18

    Most reported studies with animal models of abdominal aortic aneurysm (AAA) and several studies with patients have suggested that doxycycline favourably modifies AAA; however, a recent large long-term clinical trial found that doxycycline did not limit aneurysm growth. Thus, there is currently no convincing evidence that doxycycline reduces AAA expansion. Here, we critically review the available experimental and clinical information about the effects of doxycycline when used as a pharmacological treatment for AAA. The view that AAA can be considered an autoimmune disease and the observation that AAA tissue shows clonal expansion of T cells is placed in the light of the well-known inhibition of mitochondrial protein synthesis by doxycycline. In T cell leukaemia animal models, this inhibitory effect of the antibiotic has been shown to impede T cell proliferation, resulting in complete tumour eradication. We suggest that the available evidence of doxycycline action on AAA is erroneously ascribed to its inhibition of matrix metalloproteinases (MMPs) by competitive binding of the zinc ion co-factor. Although competitive binding may explain the inhibition of proteolytic activity, it does not explain the observed decreases of MMP mRNA levels. We propose that the observed effects of doxycycline are secondary to inhibition of mitochondrial protein synthesis. Provided that serum doxycycline levels are kept at adequate levels, the inhibition will result in a proliferation arrest, especially of clonally expanding T cells. This, in turn, leads to the decrease of proinflammatory cytokines that are normally generated by these cells. The drastic change in cell type composition may explain the changes in MMP mRNA and protein levels in the tissue samples.

  3. Endovascular Repair of Abdominal Aortic Aneurysms: Analysis of Aneurysm Volumetric Changes at Mid-Term Follow-Up

    SciTech Connect

    Bargellini, Irene Cioni, Roberto; Petruzzi, Pasquale; Pratali, Alessandro; Napoli, Vinicio; Vignali, Claudio; Ferrari, Mauro; Bartolozzi, Carlo

    2005-05-15

    Purpose. To evaluate the volumetric changes in abdominal aortic aneurysms (AAA) after endovascular AAA repair (EVAR) in 24 months of follow-up. Methods. We evaluated the volume modifications in 63 consecutive patients after EVAR. All patients underwent strict duplex ultrasound and computed tomography angiography (CTA) follow-up; when complications were suspected, digital subtraction angiography was also performed. CTA datasets at 1, 6, 12, and 24 months were post-processed through semiautomatic segmentation, to isolate the aneurysmal sac and calculate its volume. Maximum transverse diameters (Dmax) were also obtained in the true axial plane, Presence and type of endoleak (EL) were recorded. A statistical analysis was performed to assess the degree of volume change, correlation with diameter modifications, and significance of the volume increase with respect to ELs. Results. Mean reconstruction time was 7 min. Mean volume reduction rates were 6.5%, 8%, and 9.6% at 6, 12, and 24 months follow-up, respectively. Mean Dmax reduction rates were 4.2%, 6.7%, and 12%; correlation with volumes was poor (r = 0.73-0.81). ELs were found in 19 patients and were more frequent (p = 0.04) in patients with higher preprocedural Dmax, The accuracies of volume changes in predicting ELs ranged between 74.6% and 84.1% and were higher than those of Dmax modifications. The strongest independent predictor of EL was a volume change at 6 months {<=}0.3% (p = 0.005), although 6 of 19 (32%) patients with EL showed no significant AAA enlargement, whereas in 6 of 44 (14%) patients without EL the aneurysm enlarged. Conclusion. The lack of volume decrease in the aneurysm of at least 0.3% at 6 months follow-up indicates the need for closer surveillance, and has a higher predictive accuracy for an endoleak than Dmax.

  4. Association of non-synonymous variants in WIPF3 and LIPA genes with abdominal aortic aneurysm: an autopsy study

    PubMed Central

    Maeda, Yuko; Sato, Noriko; Naka-Mieno, Makiko; Mori, Seijiro; Arai, Tomio; Tanaka, Masashi; Muramatsu, Masaaki; Sawabe, Motoji

    2016-01-01

    Background Abdominal aortic aneurysm (AAA) is a multifactorial disease with strong genetic components. Various genetic loci have been associated with clinical AAA, but few studies have investigated pathological AAA, an intermediate phenotype of the disease. Methods We examined 2263 consecutive autopsies of older Japanese subjects from a study on geriatric diseases in Japanese individuals (The JG-SNP study). The presence of AAA was determined with a pathological diagnosis during autopsy. Single nucleotide variants (SNVs) associated with AAA were determined with an Illumina HumanExome Beadchip array. Logistic regression analyses were performed to determine genetic associations. Age, gender, and other risk factors of AAA were analyzed as covariates. Results 118 subjects with AAA and 2145 subjects without AAA were analyzed in a case-control setting. No variants reached significance after applying the Bonferroni correction (P < 2.05×10−6). The strongest associations were found with rs3750092 (p.E321G, OR: 0.36, 95% CI: 0.24–0.56, P = 6.09 × 10−6), a variant in the WAS/WASL interacting protein family 3 (WIPF3), and with rs1051338 (p.T16P, OR: 2.50, 95% CI: 1.70–3.66, P = 2.79 × 10−6) and rs2246942 (intronic, OR: 2.32, 95% CI: 1.58–3.41, P = 1.61 × 10−5), variants in the lysosomal acid lipase A (LIPA). LIPA is essential for macrophage cholesterol metabolism. Immunohistological analyses of WIPF3 protein in AAA samples from three subjects revealed that WIPF3 was expressed in macrophages of atheromatous plaques. Conclusions This study suggests that WIPF3 and LIPA, both of which are expressed in the macrophages are involved in pathological AAA. These results should be regarded as hypothesis-generating; thus, replication study is warranted. PMID:28321238

  5. Free-breathing black-blood CINE fast-spin echo imaging for measuring abdominal aortic wall distensibility: A feasibility study.

    PubMed

    Lin, Jyh-Miin; Patterson, Andrew; Chao, Tzu-Cheng; Zhu, Chengcheng; Chang, Hing-Chiu; Mendes, Jason; Chung, Hsiao-Wen; Gillard, Jonathan; Graves, Martin

    2017-03-22

    The paper reports a free-breathing black-blood CINE fast-spin echo (FSE) technique for measuring abdominal aortic wall motion. The free-breathing CINE FSE includes the following MR techniques: 1) variable-density sampling with fast iterative reconstruction; 2) inner-volume imaging; and 3) a blood-suppression preparation pulse. The proposed technique was evaluated in eight healthy subjects. The inner-volume imaging significantly reduced the intraluminal artifacts of respiratory motion (p = 0.015). The quantitative measurements were a diameter of 16.3 ± 2.8 mm and wall distensibility of 2.0 ± 0.4 mm (12.5 ± 3.4%) and 0.7 ± 0.3 mm (4.1 ± 1.0%) for the anterior and posterior walls, respectively. The cyclic cross-sectional distensibility was 35 ± 15% greater in the systolic phase than in the diastolic phase. In conclusion, we developed a feasible CINE FSE method to measure the motion of the abdominal aortic wall, which will enable clinical scientists to study the elasticity of the abdominal aorta.

  6. Significant changes in combined consistent biomarkers and computed tomography angiography revealed during an interval of 6months before abdominal aortic aneurysm rupture.

    PubMed

    Szumilowicz, Pawel; Wiernicki, Ireneusz; Kazimierczak, Arkadiusz; Golubinska-Szemitko, Elzbieta; Zurkowska, Joanna; Kasprzak, Piotr

    2017-02-28

    The most commonly used predictor of rupture of abdominal aortic aneurysm (AAA) is the diameter, but this does not correlate well with the risk of rupture. Therefore, in order to make further improvements in clinical decisions regarding AAA patients, the development of additional predictive tools other than aneurysm size alone is needed. We herein report a case of a 72-year-old man with AAA that underwent rupture transformation during six months. We review the morphological features changes detected by computed tomography and also observe several alters circulating biomarkers at the same time. In the study presented essentially an association of those combined parameters with the risk of AAA impending rupture.

  7. Synchronous infection of the aorta and the testis: emphysematous epididymo-orchitis, abdominal aortic mycotic aneurysm, and testicular artery pseudoaneurysm diagnosed by use of MDCT.

    PubMed

    Hegde, Rahul G; Balani, Ankit; Merchant, Suleman A; Joshi, Anagha R

    2014-07-01

    We report clinical details and imaging findings for a case of emphysematous epididymo-orchitis with co-existing mycotic abdominal aortic aneurysm and a testicular artery pseudoaneurysm in a diabetic 65-year-old male. We report imaging findings from ultrasonography (USG) and contrast-enhanced multidetector computed tomography (MDCT). Use of MDCT to identify, confirm, and define the extent of the disease, and its utility in understanding the pathogenesis of this rare condition are highlighted. For such lethal infections, early diagnosis and intervention can be lifesaving; imaging can be of crucial importance in this.

  8. High serum thrombospondin-1 concentration is associated with slower abdominal aortic aneurysm growth and deficiency promotes angiotensin-II induced aneurysm in mice.