abdominal aortic aneurysm Dotaz Zobrazit nápovědu
We present comprehensive biomechanical analyses of abdominal aortic aneurysms (AAA) for 43 patients. We compare stress magnitudes and stress distributions within arterial walls of abdominal aortic aneurysms (AAA) obtained using two simulation and modelling methods: (a) Fully automated and computationally very efficient linear method embedded in the software platform Biomechanics based Prediction of Aneurysm Rupture Risk (BioPARR), freely available from https://bioparr.mech.uwa.edu.au/; (b) More complex and much more computationally demanding Non-Linear Iterative Stress Analysis (Non-LISA) that uses a non-linear inverse iterative approach and strongly non-linear material model. Both methods predicted localised high stress zones with over 90% of AAA model volume fraction subjected to stress below 20% of the 99th percentile maximum principal stress. However, for the non-linear iterative method, the peak maximum principal stress (and 99th percentile maximum principal stress) was higher and the stress magnitude in the low stress area lower than for the automated linear method embedded in BioPARR. Differences between the stress distributions obtained using the two methods tended to be particularly pronounced in the areas where the AAA curvature was large. Performance of the selected characteristic features of the stress fields (we used 99th percentile maximum principal stress) obtained using BioPARR and Non-LISA in distinguishing between the AAAs that would rupture and remain intact was for practical purposes the same for both methods.
- Klíčová slova
- abdominal aortic aneurysm, finite element method, patient-specific modelling, rupture, stress,
- MeSH
- analýza metodou konečných prvků MeSH
- aneurysma břišní aorty * MeSH
- aorta abdominalis MeSH
- biomechanika MeSH
- lidé MeSH
- mechanický stres MeSH
- modely kardiovaskulární MeSH
- ruptura aorty * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
INTRODUCTION: Biomechanical rupture risk assessment of abdominal aortic aneurysm (AAA) requires information about failure properties of aneurysmal tissue. There are large differences between reported values. Among others, studies vary in using either axially or circumferentially oriented samples. This study investigates the effect of sample orientation on failure properties. METHODS: Aneurysmal tissues from 45 patients (11 females) were harvested during open AAA repair, cut into uniaxial samples (90) and tested mechanically within 3 h. If possible, the samples were cut in both axial (49 samples) and circumferential (41 samples) directions. Wall thickness, First Piola-Kirchhoff strength Pult and ultimate tension Tult were recorded. Influence of sample orientation and other clinical parameters were investigated using non parametric tests. RESULTS: Medians of Pult (values 1100 kPa for circumferential vs. 715 kPa for axial direction, p < 10-4) and Tult (17.4 N/cm in circumferential vs. 11.2 N/cm in axial direction, p < 10-4) were significantly higher in circumferential direction. For paired data, the median of difference was 411 kPa (p < 10-3) in Pult and 7.4 N/cm (p < 10-4) in Tult in favor of circumferential direction. CONCLUSIONS: In this first study of anisotropy in AAA wall failure properties using paired comparisons, the strength in circumferential orientation was found to be higher than in axial orientation.
- Klíčová slova
- Abdominal aortic aneurysm, Failure properties, Mechanical testing, Sample orientation,
- MeSH
- aneurysma břišní aorty * MeSH
- anizotropie MeSH
- biomechanika MeSH
- hodnocení rizik MeSH
- lidé MeSH
- mechanický stres MeSH
- ruptura aorty * MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The objectives of this study were to evaluate patients with aortic abdominal aneurysm (AAA) with regard to immunoglobulin (Ig)G4-related disease (IgG4-RD). IgG4-RD represents a recently defined condition comprised of a collection of disorders characterized by IgG4 hypergammaglobulinemia, the presence of IgG4-positive plasma cells in organs affected with fibrotic or sclerotizing changes and typical histopathological features. It was identified as a possible cause of vasculitis in large vessels. Studies have been published on a possible association between inflammatory aortic or cardiovascular disease and IgG4-RD. We examined 114 patients with AAA requiring surgery in order to identify findings which are characteristic of IgG4-RD. Aneurysm samples from seven patients showed histopathological features consistent with IgG4-RD and the presence of IgG4+ plasma cells. Only two of these seven patients showed elevated IgG4 serum levels higher 1·35 g/l. In five of the patients, the concentration of serum IgG4 was lower than 1·20 g/l, with the number of IgG4+ plasma cells being higher than 50/high-power field. These findings were consistent with AAA being a heterogeneous group of inflammatory diseases with different pathogenesis.
- Klíčová slova
- IgG4, IgG4-related disease, aortic abdominal aneurysm, diagnostic value, histopathology,
- MeSH
- aneurysma břišní aorty krev imunologie patologie MeSH
- aorta imunologie metabolismus patologie MeSH
- hypergamaglobulinemie krev imunologie patologie MeSH
- IgG4 asociovaná nemoc krev imunologie patologie MeSH
- imunoglobulin G krev imunologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- plazmatické buňky imunologie metabolismus patologie MeSH
- retrospektivní studie MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky MeSH
- práce podpořená grantem MeSH
- Názvy látek
- imunoglobulin G MeSH
PURPOSE: The purpose of this study was to evaluate the main factors of the 30-day mortality rate in patients operated on for rupture of abdominal aortic aneurysm (RAAA). PATIENTS AND METHOD: Univariate and multivariate analysis of various factors associated with RAAA was performed in the group of 182 patients operated on for RAAA between 1/1/1992 to 1/9/2005. RESULTS: The 30-day mortality rate was 33.5%. The main mortality factors were: misdiagnosis, cardiopulmocerebral resuscitation (CPCR) on admission, configuration of RAAA(p<0.001), number of blood transfusions, hypotension on admission (p<0.0001) and duration of operation, type of reconstruction and hypertension in history (p<0.01). Important factors (p<0.05) of postoperative mortality included also low haemoglobin level on admission, abdominal aortic aneurysm (AAA) diameter and ischaemic heart disease in history. The probability of patient's death is the highest (p<0.003), if factors like CPCR, number of blood transfusions and aneurysm diameter are combined (multivariate analysis, stepwise method). CONCLUSION: The early detection and surgical or endovascular elective treatment of AAA, regular dispensarization of patients with small AAA, especially hypertonics, correct diagnosis of RAAA without time delay, are the best tools for patients survival. The patient's survival increases with trained prehospital resuscitation system and experienced team of vascular surgeons and anestesiologists in centres (Tab. 3, Ref. 20).
BACKGROUND/AIM: As the population ages, there are increasing findings of coincidental diseases such as abdominal aortic aneurysm (AAA) and intra-abdominal, retroperitoneal malignancy. The aim of this study was to propose an optimal treatment procedure for these patients. PATIENTS AND METHODS: Over a twenty-year-period, surgery was performed on a total of 1,098 patients with AAA and 32 (2.9%) patients with AAA and intra-abdominal, retroperitoneal malignancy: 18 renal, 6 colorectal carcinomas, 3 carcinomas of the small intestine, 3 primary liver tumours, 1 stomach carcinoma and 1 teratoma. The median age of patients was 72.5 years, there were 20 men (62.5%) and 12 women (37.5%). A one-stage procedure was performed on 19 patients (59.4%), and a two-stage procedure on 13 (40.6%) patients. RESULTS: The average time of hospitalization was 12.4±6.9 days (median=11.0 days) for one-stage procedure, for a two-stage procedure 21.3±9.3 days (median=20.0 days), p=0.0045. Seven patients (21.9%) died within 30 days after the operation. All the deaths were in the group of one-stage procedures (p=0.0252). The 1-, 3- and 5-year overall survival for patients following one-stage and twostage procedures was 61.0/56.3/51.5% and 89.0/79.9/53.0% respectively (p=0.1199). CONCLUSION: Symptomatic disease must be resolved first. Two-stage procedures are the method of choice and offer better short-term results compared to one-stage procedures.
- Klíčová slova
- Abdominal aortic aneurysm, intra-abdominal, long-term results, retroperitoneal malignancy, surgical procedures,
- MeSH
- aneurysma břišní aorty * komplikace epidemiologie chirurgie MeSH
- karcinom z renálních buněk * MeSH
- lidé MeSH
- nádory ledvin * MeSH
- nádory žaludku * MeSH
- retroperitoneální nádory * chirurgie MeSH
- senioři MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Abdominal aortic aneurysm (AAA) is a relatively frequent and serious condition in vascular surgery. The diagnostic and indication process and its treatment are driven by the guidelines which dictate an intervention when the maximum AAA diameter is more than 55 mm. Nevertheless, this approach is not fully sufficient in all AAA cases and thus we have been seeking to develop a modern diagnostic tool using computer modeling and vascular wall stress analysis. METHODS: The project has been ongoing in cooperation with engineers from VUT Brno (Brno University of Technology) and VŠB Ostrava (Technical University of Ostrava) for ten years. The design of the analytical tool was created during the first, experimental period of the project; this tool is able to assess vascular wall stress from regular CT scans using the finite element method. This primary model was gradually altered and its precision was increased considerably in the course of the years using data from mechanical and histological tests of AAA wall specimens harvested during open repairs. Additionally, other patient specific data are included in the analysis such as blood pressure, gender and material characteristics. RESULTS: The effectiveness of the method was evaluated in a pseudo-prospective study, showing clear superiority of the vascular wall stress analysis over the maximum diameter approach. The method was used in clinical practice for the first time during restrictions due to the COVID-19 pandemic; based on the analysis we were able to assess which AAA cases can be postponed and which had a high risk of rupture and an intervention was required despite the restrictions. The method achieved 100% sensitivity, and its specificity was also much better compared to the maximum diameter approach. CONCLUSION: The vascular wall stress analysis of AAA seems to be much more precise than the classic indication approach based only on the maximum diameter, and it can be used to determine the therapy based on patient specific parameters.
- Klíčová slova
- COVID-19 pandemic, abdominal aortic aneurysm, finite element method, indication process, vascular wall stress,
- MeSH
- aneurysma břišní aorty * diagnostické zobrazování chirurgie MeSH
- aorta abdominalis MeSH
- COVID-19 * MeSH
- lidé MeSH
- mechanický stres MeSH
- pandemie MeSH
- prospektivní studie MeSH
- ruptura aorty * patologie MeSH
- testování na COVID-19 MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
AIMS: There is increased prevalence of inguinal hernia (ΙΗ) in patients with abdominal aortic aneurysm (AAA). As there is limited data on AAA in patients with ΙΗ our objective was to examine the prevalence of AAA in such patients. METHODS: We prospectively examined 185 consecutive patients for AAA who presented to our department for surgical repair of an ΙΗ. All patients were referred for ultrasound of the abdominal aorta. An AAA was considered to be present when the distal diameter of the abdominal aorta was over 3 cm. Patients with no AAA were followed annually with an abdominal ultrasound for 5 years. RESULTS: Out of the 185 patients (179 males, 6 females) aged from 35-81 (mean 58.6 years), AAA initially appeared in 28 patients with a mean age 61.2 years old. The range of the aortic distal diameter was between 3.4 and 8.1 cm with a mean diameter of 4.8 cm in patients with AAA. The prevalence of the ΑΑΑ was increased in smokers, with hypertension and with bilateral and direct hernia. At the end of the 5 years follow-up, 16 more patients had developed an AAA of mean diameter 3.2 cm (3-4.1 cm), increasing the prevalence of AAA to 27.7%. CONCLUSION: There is an increased prevalence of AAA in patients with ΙΗ, especially in smokers, with hypertension and with bilateral and/or direct hernia. Hence, periodic ultrasonound may play an important role in screening and early diagnosis of AAA in these patients.
- Klíčová slova
- abdominal aortic aneurysm, aorta, inguinal hernia, screening, ultrasound,
- MeSH
- aneurysma břišní aorty komplikace diagnostické zobrazování MeSH
- dospělí MeSH
- inguinální hernie komplikace chirurgie MeSH
- lidé středního věku MeSH
- lidé MeSH
- operace kýly statistika a číselné údaje MeSH
- prevalence MeSH
- prospektivní studie MeSH
- rizikové faktory MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ultrasonografie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Řecko epidemiologie MeSH
BACKGROUND AND OBJECTIVE: Estimating patient specific annual risk of rupture of abdominal aortic aneurysm (AAA) is currently based only on population. More accurate knowledge based on patient specific data would allow surgical treatment of only those AAAs with significant risk of rupture. This would be beneficial for both patients and health care system. METHODS: A methodology for estimating annual risk of rupture (EARR) of abdominal aortic aneurysms (AAA) that utilizes Bayesian statistics, mechanics and patient-specific blood pressure monitoring data is proposed. EARR estimation takes into consideration, peak wall stress in AAA computed by patient-specific finite element modeling, the probability distributions of wall thickness, wall strength, systolic blood pressure and the period of time that the patient is known to have already survived with the intact AAA. Initial testing of proposed approach was performed on fifteen patients with intact AAA (mean maximal diameter 51mm±8mm). They were equipped with a pressure holter and their blood pressure was recorded over 24 hours. Then, we calculated EARR values for four possible scenarios - without considering any days of survival prior identification of AAA at computed tomography scans (EARR_0), considering past survival of 30 (EARR_30), 90 (EARR_90) and 180 days (EARR_180). Finally, effect of patient-specific blood pressure variability was analyzed. RESULTS: Consideration of past survival does indeed significantly improve predictions of future risk: EARR_30 (1.04%± 0.87%), EARR_90 (0.67%± 0.56%) and EARR_180 (0.47%± 0.39%) which are unrealistically high otherwise (EARR_0 5.02%± 5.24%). Finally, EARR values were observed to vary by an order as a consequence of blood pressure variability and by factor of two as a consequence of neglected growth. CONCLUSIONS: Methodology for computing annual risk of rupture of AAA was developed for the first time. Sensitivity analyses showed respecting patient specific blood pressure is important factor and should be included in the AAA rupture risk assessment. Obtained EARR values were generally low and in good agreement with confirmed survival time of investigated patients so proposed method should be further clinically validated.
- Klíčová slova
- Abdominal Aortic Aneurysm, Annual risk of rupture, Bayesian statistics, Rupture Risk Assessment,
- MeSH
- aneurysma břišní aorty * diagnostické zobrazování MeSH
- Bayesova věta MeSH
- hodnocení rizik MeSH
- lidé MeSH
- mechanický stres MeSH
- modely kardiovaskulární MeSH
- počítačová rentgenová tomografie MeSH
- počítačové modelování podle konkrétního pacienta MeSH
- rizikové faktory MeSH
- ruptura aorty * diagnostické zobrazování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Ruptured abdominal aortic aneurysm (AAA) remains to be represent a common and highly lethal problem. We reviewed the records of 92 patients (73 men and 19 women) operated on for ruptured infrarenal AAA within the past 10 years (January 1989 to October 1999) in the 2nd Department of Surgery in Brno, Czech Republic. The mean age was 71 years (range 57 to 92 years). Only 10 patients (10.9%) were known to have an AAA before the rupture. Preoperative systolic blood pressure below 90 mmHg was present in 70 patients (76%) and 15 patients (16.3%) experienced cardiac arrest before surgery. The in-hospital mortality rate was 47.8% (44 patients). Among the total of 92 patients, haemoperitoneum was discovered only in 30 patients (32.6%) with the mortality rate of 40% (12 patients). In 62 patients (67.4%) also hemoperitoneum was present, the mortality rate was 51.6% (32 patients) in these patients. Multiorgan failure due to an irreversible hemorrhagic shock was the main cause of death in 23 patients (25%). Further causes were: heart failure--8 patients (8.7%), pulmonary complications--5 patients (5.4%), renal failure--4 patients (4.3%), bleeding--3 patients (3.3%), and sepsis--1 patient (1.1%). The patient's prognosis depends on early diagnostics and on the quality of peroperative and postoperative care. (Tab. 2, Ref. 8.)
- MeSH
- aneurysma břišní aorty diagnóza mortalita chirurgie MeSH
- lidé středního věku MeSH
- lidé MeSH
- míra přežití MeSH
- ruptura aorty diagnóza mortalita chirurgie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSES: A ruptured AAA (rAAA) is a common cause of death in males over 60 years of age, and the global mortality from rAAA exceeds 80 %. The pathological processes occurring in the wall of the developing AAA are still unclear. The potential pathophysiological mechanisms underlying aortic aneurysms have been examined by many studies using immunohistochemistry and were, therefore, targeted at specific, preselected protein antigens. METHODS: We collected samples of tissue from anterior wall of an aneurysm sac from 15 patients indicated for AAA resection (group A) during the period from 2010 to 2011. These samples were subjected to a proteomic analysis. In addition, we collected control samples of identical aortic tissue from 10 heart-beating deceased organ donors (group B). RESULTS: A total of 417 differentially expressed protein fractions were identified, 18 of which were only detected in the healthy controls, while 85 were specific for aneurysm tissue and 314 were detectable in both groups. In 175 protein fractions, the gel-derived spot volumes differed significantly between aneurismal and healthy aortic tissue. CONCLUSIONS: We found a significant difference in the proteome of the AAA tissue and non-dilated aortic tissue. We demonstrated that the AAA proteome is considerably richer and more varied than the healthy and atherosclerotic aorta. We believe that our results clearly demonstrate a completely different etiopathogenesis of atherosclerosis and aneurismal disease.
- MeSH
- 2D gelová elektroforéza MeSH
- aneurysma břišní aorty genetika metabolismus MeSH
- ateroskleróza genetika MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- proteom genetika metabolismus MeSH
- proteomika * metody MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- proteom MeSH