Abdominal Aneurysm Research Articles

Arteriovenous Fistula Caused by Ruptured Abdominal Aortoiliac Aneurysm.

Teaching point: A ruptured aorto-iliac aneurysm, complicated by an iliac arteriovenous fistula, is rare but has a possibly fatal outcome and requires prompt diagnosis and appropriate treatment.

Sneddon’s syndrome-like manifestation as a presentation of abdominal aortic aneurysm thrombosis

Sneddon’s syndrome-like manifestation as a presentation of abdominal aortic aneurysm thrombosis

Exploration of small molecule compounds targeting abdominal aortic aneurysm based on CMap database and molecular dynamics simulation.

The mitigation of abdominal aortic aneurysm (AAA) growth through pharmaceutical intervention offers the potential to avert the perils associated with AAA rupture and the subsequent need for surgical intervention. Nevertheless, the existing effective drugs for AAA treatment are limited, necessitating a pressing exploration for novel therapeutic medications. AAA-related transcriptome data were downloaded from GEO, and differentially expressed genes (DEGs) in AAA tissue were screened for GO and KEGG enrichment analyses. Small molecule compounds and their target proteins with negative connectivity to the AAA expression profile were predicted in the Connectivity Map (CMap) database. Molecular docking and molecular dynamics simulation were performed to predict the binding of the target protein to the small molecule compound, and the MM/GBSA method was used to calculate the binding free energy. Cluster analysis was performed using the cluster tool in the GROMACS package. An AAA cell-free model was built, and CETSA experiments were used to demonstrate the binding ability of small molecules to the target protein in cells. A total of 2244 DEGs in AAA were obtained through differential analysis, and the DEGs were mainly enriched in the tubulin binding biological function and cell cycle pathway. The CMap results showed that Apicidin had a potential therapeutic effect on AAA with a connectivity score of -97.74, and HDAC4 was the target protein of Apicidin. Based on literature, HDAC4-Apicidin was selected as the subsequent research object. The lowest affinity of Apicidin-HDAC4 molecular docking was -8.218kcal/mol. Molecular dynamics simulation results indicated that Apicidin-HDAC4 could form a stable complex. MM/GBSA analysis showed a total binding free energy of -55.40 ± 0.79kcal/mol, and cluster analysis showed that there were two main conformational clusters during the binding process, accounting for 22.4% and 57.8%, respectively. Apicidin could form hydrogen bonds with surrounding residues for stable binding. CETSA experiment proved the stable binding ability of Apicidin and HDAC4. Apicidin inhibited HDAC4 in AAA and exhibited favorable protein-ligand interactions and stability, making it a potential candidate drug for treating AAA.

Isolated Abdominal Aortic Dissection With and Without Abdominal Aortic Aneurysm.

The aim of this study was to report the clinical presentation and treatment outcomes of patients treated for IAAD with and without abdominal aortic aneurysm (AAA) in a single academic institution in South America. A retrospective review of all patients with IAAD with or without concomitant AAA between January 2002 and December 2023 from a single academic hospital was performed. Eighteen patients with IAAD were diagnosed of whom 13 (72.2%) were males. Median age was 63 years (range: 43-88 years). Sixteen (88.8%) patients presented with symptoms, and in two (11.1%) asymptomatic patients IAAD was an incidental finding. Ten (55.5%) patients had concomitant abdominal aortic aneurysm (AAA), with a median size of the aneurysm of 49.5mm (range: 44-66mm). No statistical differences in baseline characteristics were seen between patients with concomitant IAAD and AAA and patients with only IAAD. Seven (38.8%) patients presented chronic dissection, and 11 (61.1%) patients had acute dissection. Five (27.7%) patients were treated conservatively with blood pressure, pain control, and antiplatelets; endovascular surgery was performed in eight (44.4%) patients and open surgery in five (27.7%) patients. The complication rate was 22.2% (n = 4), and the mortality rate was 0%. Median follow-up was 36 months (range: 6-240 months). Complete remodeling was seen in all patients except two patients who underwent conservative treatment. Of those, one had partial remodeling, and the other no changed. Isolated aortic dissection of the abdominal aorta is an uncommon condition, with acceptable different treatment strategies, from conservative to invasive treatments. Sometimes IAAD can concur with AAA, and when so, invasive treatment might be considered. More studies describing the natural history of AAA and its association with IAAD are warranted, as well as further research reporting long-term outcomes on aortic remodeling after different treatment modalities.

Prevalence of abdominal aortic aneurysm in patients with hidradenitis suppurativa in the Veterans Affairs Health Care System.

Our study investigated the relationship between abdominal aortic aneurysm (AAA) and hidradenitis suppurativa (HS) in patients within the Veterans Affair Health Care System. Overall, we found that patients with HS had a higher prevalence of AAA compared to those without HS, with women and men with HS having higher odds of AAA. Further research should consider clinical outcomes such as AAA rupture and associated mortality.

The Effects of Colchicum Dispert and Bone Marrow-Derived Mesenchymal Stem Cell Therapy on Skeletal Muscle Injury in a Rat Aortic Ischemia-Reperfusion Model.

Abdominal aortic aneurysms and peripheral artery disease pose significant health risks, ranking third after heart attacks and cerebral strokes. Surgical interventions often involve temporary aortic clamping, leading to ischemia-reperfusion injury and tissue damage. Colchicine and mesenchymal stem cells have shown promise, individually, in mitigating ischemia-reperfusion injury, but their combined effects remain understudied. This study utilized 42 male Wistar rats, divided into six groups: Control, Sham, Ischemia-Reperfusion, Colchicine, Mesenchymal stem cell, and Mix (colchicine and mesenchymal stem cell). The ischemia-reperfusion model involved clamping the abdominal aorta for 60 min, followed by 120 min of reperfusion. Colchicine and mesenchymal stem cell treatments were administered as pre- and post-ischemia interventions, respectively. Mesenchymal stem cells were cultured, characterized by flow cytometry, and verified for specific surface antigens. Blood and tissue samples were analyzed for oxidative stress markers, nitric oxide metabolites, and apoptosis using TUNEL. There were significant differences between the groups in terms of the serum total antioxidant capacity (p < 0.001) and inflammation markers (ischemia-modified albumin, p = 0.020). The combined therapy group (Mix) exhibited the lowest inflammation levels. Arginine levels also showed significant variation (p = 0.028), confirming the ischemia-reperfusion injury model. In muscle tissues, the total antioxidant capacity (p = 0.022), symmetric dimethylarginine, and citrulline levels (p < 0.05) indicated nitric oxide metabolism. Apoptosis was notably high in the ischemia-reperfusion injury group as anticipated. It appeared to be reduced by colchicine, mesenchymal stem cells, and their combination, with the most significant decrease observed in the Mix group (p < 0.001). This study highlights the potential of using combined colchicine and mesenchymal stem cell therapy to reduce muscle damage caused by ischemia-reperfusion injury. Further research is needed to understand the underlying mechanisms and confirm the clinical significance of this approach in treating extremity ischemia-reperfusion injuries.

Aortic atherosclerotic disease and abdominal aortic aneurysm in patients with genetically verified familial hypercholesterolaemia

Aortic atherosclerotic disease and abdominal aortic aneurysm in patients with genetically verified familial hypercholesterolaemia

Right-to-left shunt due to iatrogenic atrial septal defect manifested by aorto-caval fistula: a case report

BackgroundAn aorto-caval fistula is a rare but critical complication of abdominal aortic aneurysm (AAA) rupture, leading to high-output heart failure and increased venous pressure. The anesthetic management of such cases, particularly when complicated by an intraoperative right-to-left shunt, is seldom reported.Case presentationA 71-year-old man with a history of atrial fibrillation and catheter ablation presented with heart failure and abdominal pain, leading to cardiac arrest. Imaging revealed an AAA rupture into the inferior vena cava. During emergency surgery, severe venous bleeding was managed using intra-aortic balloon occlusion (IABO). Transesophageal echocardiography (TEE) identified a right-to-left shunt due to an iatrogenic atrial septal defect.ConclusionEarly TEE recognition and timely IABO intervention were crucial in managing this complex case, underscoring the importance of these techniques in similar emergency scenarios.

LncRNAs in response to endoplasmic reticulum stress: Novel players in abdominal aorta aneurysm pathophysiology

lncRNAs in response to endoplasmic reticulum stress: Novel players in abdominal aorta aneurysm pathophysiology

Olfactory receptor 2 signaling drives abdominal aortic aneurysm formation

Olfactory receptor 2 signaling drives abdominal aortic aneurysm formation

Prdx3 deficiency aggravates abdominal aortic aneurysm by inducing vascular smooth muscle cell senescence

Prdx3 deficiency aggravates abdominal aortic aneurysm by inducing vascular smooth muscle cell senescence

Metformin Use and Long-term Outcomes Including Aneurysm Sac Dynamics Following EVAR for Infrarenal Abdominal Aortic Aneurysm: "A Retrospective Study".

Metformin, widely used for the treatment of diabetes mellitus (DM), has shown potential for inhibiting abdominal aortic aneurysm (AAA) growth by reducing extracellular matrix remodeling and inflammation. However, its influence on clinical outcomes and aneurysm sac dynamics after endovascular aneurysm repair (EVAR) remains uncertain. This retrospective study aims to explore the effects of metformin on long-term outcomes following EVAR. Patients who underwent elective standard EVAR for infrarenal AAA at a single academic Dutch hospital from 2000 to 2022 were included. We collected baseline patient demographics, comorbid conditions, anatomical and operative characteristics, and 30-day postoperative events. Metformin use was defined as using it preceding EVAR. The primary outcome, the postoperative aneurysm sac volume over time, was investigated using linear mixed-effects modeling. The secondary outcomes, 8-year all-cause mortality and freedom from graft-related events, were evaluated using Kaplan-Meier methods. We analyzed 685 patients, including 634 (93%) non-metformin users and 51 (7%) metformin users. The median follow-up period was similar (4.0 years [IQR=1.5, 6.5] vs 5.0 years [IQR=2.0, 8.0]; p=0.091). Patients on metformin had a preoperative aneurysm sac volume of 153 cc (IQR=114, 195) compared with 178 cc (IQR=133, 240) for non-metformin patients (p=0.054). At 30 days post-EVAR, metformin patients had a comparable mean aneurysm sac volume compared with non-metformin patients (metformin: -19.4 cc [95% confidence interval [CI]: -47.4, 8.5]; p=0.173). The effect of metformin on aneurysm growth over time was not significant (-3.9 cc/year; [95% CI: -22.7, 14.9]; p=0.685). Following risk-adjusted analysis, metformin use was associated with similar rates of all-cause mortality (metformin vs no metformin: 50% vs 44%; hazard ratio [HR]=1.11, 95% CI: 0.66, 1.88; p=0.688) and freedom from graft-related events (metformin vs no metformin: 63% vs 66%; HR=1.82, 95% CI: 0.98, 3.38; p=0.059). Although metformin use may reduce preoperative AAA growth, it does not seem to influence overall/long-term post-EVAR AAA sac dynamics, all-cause mortality, or freedom from graft-related events. These findings suggest that the potential protective effect of metformin on AAA may not be sustained after EVAR. Further prospective studies are needed to investigate the mechanisms underlying the potential role of metformin in AAA management following EVAR. There is currently no approved pharmacological treatment available to slow the abdominal aortic aneurysm (AAA) growth rate and reduce the related risk of rupture. In our retrospective analysis including 685 patients undergoing EVAR for infrarenal AAA, we found that metformin use was not associated with improved post-EVAR outcomes, such as a reduction of aneurysm sac volume over time, eight-year all-cause mortality, or freedom of graft-related events. These findings suggest that the potential protective effect of metformin on AAA may not be sustained after EVAR and underscore the need for ongoing research into this area.

Effects of a high-phosphate diet on vascular calcification and abdominal aortic aneurysm in mice.

Vascular aging is an important risk factor for cardiovascular diseases, including abdominal aortic aneurysm (AAA) and pathological aortic dilatation, playing a critical role in the morbidity and mortality of older adults. Vascular calcification, a phenotype of vascular aging, is frequently associated with AAA. However, this association remains unclear owing to the lack of animal models. This study investigated the effects of a high-phosphate diet (HPD), a prominent trigger of vascular calcification in AAA. Eight-week-old male mice were fed either a normal diet (ND; Ca 1.18%/P 1.07% = 1.10) or an HPD (Ca 1.23%/P 1.65% = 0.75) for 4 weeks. Subsequently, AAA was induced using CaCl2 application and angiotensin II (AngII) infusion for 4 weeks. The HPD resulted in more pronounced AAA formation than did the ND. Importantly, vascular calcification was observed only in the aorta of the HPD mice. Enhanced Runt-related transcription factor 2 expression and apoptosis (downregulation of growth arrest-specific gene 6/pAkt survival pathway), two major mechanisms of vascular calcification, were also observed. Furthermore, increased IL-6 and F4/80 expression was observed in the aorta of HPD mice. In RAW264.7 cells, inorganic phosphate enhanced IL-6 and IL-1β expression under AngII priming. Ferric citrate, a phosphate binder, significantly inhibited HPD-induced AAA formation. These findings suggest that HPD induces vascular calcification and AAA formation, possibly through inflammation. This murine model suggests that vascular calcification induced by phosphate burden may be a therapeutic target for vascular diseases, including AAA. Geriatr Gerontol Int 2024; ••: ••-••.

CD8+ T-cell deficiency protects mice from abdominal aortic aneurysm formation in response to calcium chloride2.

Abdominal aortic aneurysm (AAA) is an aneurysm-like dilated and highly fatal cardiovascular disease. CD8+ T cells have been shown to be critical for vascular pathological processes, but the contribution of these lymphocytes to vascular diseases remains elusive. Eight-week-old male wildtype (CD8+/+) and Cd8a knockout (CD8-/-) mice were used in a calcium chloride2 (CaCl2)-induced experimental AAA model. At 6 weeks after surgery, CD8+ T-cell deletion prevented the formation of AAA, accompanied by reductions of the levels of inflammatory (interferon-γ [IFN-γ], interleukin-1β, monocyte chemoattractant protein-1, intracellular adhesion molecule-1, vascular cell adhesion molecule-1, NOD-like receptor protein 3, caspase-1), oxidative stress [NADPH oxidase and gp91phox], and proteolysis (cathepsin S, cathepsin K, matrix metalloproteinase-2 [MMP-2] and MMP-9) proteins and/or genes in plasma and/or AAA tissues. Immunoreactivities of MMP-2 and MMP-9 were observed in macrophages. An injection of IFN-γ and adoptive transfer of CD8+ T cells of IFN-γ+/+ mice diminished CD8-/--mediated vasculoprotective actions in the AAA mice. In vitro, IFN-γ enhanced MMP-2 and MMP-9 gelatinolytic activities in macrophage and/or vascular smooth muscle cells. The vasculoprotective effects of CD8+ T-cell deletion in a mouse CaCl2-induced AAA model were likely attributable to, at least in part, the attenuation of IFN-γ-dependent inflammation action, oxidative stress production, and proteolysis, suggesting a novel therapeutic target for AAA formation by regulating CD8+ T-cell-derived IFN-γ secretion.

MASSIVE LATE ENDOLEAK TYPE IA, ASSOCIATED WITH SHOCK AND ACUTE ANEMIA: CONSERVATIVE SURGICAL TREATMENT

We present a case of type 1 endoleaks associated with massive hemorrhage and shock, treated with traditional open surgery. We present a 74-year-old male patient with a history of endovascular repair of abdominal aortic aneurysm 6 years ago, was admitted to the emergency department in shock and acute anemia, showing a type IA endoleak associated with retroperitoneal hematoma. Open repair was performed with the interposition of a Dacron™ prosthesis with preservation of the aortic endoprosthesis. Although in these cases of extreme urgency, it has been proposed the extraction of the endoprosthesis, which involves a procedure associated with high mortality, in this case, it was feasible a simple repair as was the interposition of prosthesis between proximal aorta and endoprosthesis. Endovascular repair of aortic aneurysm requires strict monitoring and a good selection of patients for this procedure since this late complication has a high mortality rate.

The Association of Socio-Environmental Inequality and Outcomes Among Patients Undergoing Major Surgery

IntroductionEnvironmental hazards may influence health outcomes and be a driver of health inequalities. We sought to characterize the extent to which social–environmental inequalities were associated with surgical outcomes following a complex operation. MethodsIn this cross-sectional study, patients who underwent abdominal aortic aneurysm repair, coronary artery bypass grafting, colectomy, pneumonectomy, or pancreatectomy between 2016 and 2021 were identified from Medicare claims data. Patient data were linked with social–environmental data sourced from Centers for Disease Control and Agency for Toxic Substances and Disease Registry data based on county of residence. The Environmental Justice Index social–environmental ranking (SER) was used as a measure of environmental injustice. Multivariable regression analysis was performed to assess the relationship between SER and surgical outcomes. ResultsAmong 1,052,040 Medicare beneficiaries, 346,410 (32.9%) individuals lived in counties with low SER, while 357,564 (33.9%) lived in counties with high SER. Patients experiencing greater social–environmental injustice were less likely to achieve textbook outcome (odds ratio 0.95, 95% confidence interval 0.94-0.96, P < 0.001) and to be discharged to an intermediate care facility or home with a health agency (odds ratio 0.97, 95% confidence interval 0.96-0.98, P < 0.001). ConclusionsCumulative social and environmental inequalities, as captured by the Environmental Justice Index SER, were associated with postoperative outcomes among Medicare beneficiaries undergoing a range of surgical procedures. Policy makers should focus on environmental, as well as socioeconomic injustice to address preventable health disparities.

Relationship between Gut, Blood, Aneurysm Wall and Thrombus Microbiome in Abdominal Aortic Aneurysm Patients.

Previous research confirmed gut dysbiosis and translocation of selected intestinal bacteria into the vessel wall in abdominal aortic aneurysm patients. We studied the stool, blood, thrombus and aneurysm microbiomes of 21 abdominal aortic aneurysm patients using 16S rRNA sequencing. Our goals were to determine: 1. whether the microbiome characteristic of an aneurysm differs from that of a healthy vessel, 2. whether bacteria detectable in the aneurysm are translocated from the gut through the bloodstream, 3. whether the enzymatic activity of the aneurysm microbiome can contribute to the destruction of the vessel wall. The abundance of Acinetobacter, Burkholderia, Escherichia, and Sphingobium in the aneurysm samples was significantly higher than that in the microbiome of healthy vessels, but only a part of these bacteria can come from the intestine via the blood. Environmental bacteria due to the oral cavity or skin penetration route, such as Acinetobacter, Sphingobium, Enhydrobacter, and Aquabacterium, were present in the thrombus and aneurysm with a significantly higher abundance compared to the blood. Among the enzymes of the microbiome associated with the healthy vessel wall, Iron-chelate-transporting ATPase and Polar-amino-acid-transporting ATPase have protective effects. In addition, bacterial Peptidylprolyl isomerase activity found in the aneurysm has an aggravating effect on the formation of aneurysm.

Ruptured Giant Abdominal Aortic Aneurysms

Ruptured Giant Abdominal Aortic Aneurysms

Screening for abdominal aortic aneurysm in the world and in Russia

Despite the global trend towards a decrease in the prevalence of abdominal aortic aneurysm (AAA), this disease remains one of the sudden death causes in the elderly. This necessitates the need to conduct screening studies, the effectiveness and feasibility of which has been proven in large studies, including population-based ones, and meta-analyses. The traditional and most optimal screening method is ultrasound examination. According to the guidelines of different countries, the indications for abdominal aorta ultrasound vary. Today in Russia there is no accurate data on the prevalence of AAA, while the target group for screening has not been defined, and therefore the country needs to conduct large population studies to study its prevalence and risk factors, as well as to calculate indicators of the clinical and economic effectiveness of implementation AAA screening programs.

Social Capital and Surgery Access Among Medicare Beneficiaries.

To compare the rates of unplanned procedures for access-sensitive surgical conditions among beneficiaries living in census tracts of varying social capital levels. Access-sensitive surgical conditions are conditions ideally screened for and treated in an elective setting. However, when left untreated, these conditions may result in unplanned (i.e., urgent or emergent) surgery. It is possible that social capital-the resources available to individuals through their membership in a social network-may impact the likelihood of a planned procedure occurring. Medicare beneficiaries who underwent one of three access-sensitive procedures (abdominal aortic aneurysm repair, colectomy for cancer, and ventral hernia repair) between 2016-2020 were stratified by their census tract level of social capital, the exposure variable. Outcomes included rate of unplanned surgery, readmission, 30-day mortality, and complications which were risk-adjusted with a logistic regression model that accounted for patient age, sex, race, comorbidities, and area deprivation. A total of 975,048 beneficiaries were included (mean [SD] patient age, 76 [7.6] years; 443,190 were male [45.45%]). Compared to patients from census tracts in the highest overall social capital decile, those from census tracts with the least social capital were on average more likely to undergo unplanned surgery (40.67% versus 35.28%, OR=1.26 P<0.001). Additionally, beneficiaries in these communities were also more likely to experience postoperative complications (24.99% versus 22.90%, OR=1.12 P<0.001), but there was no significant difference in rates of readmission or mortality. When evaluating only elective procedures, the differences between the lowest and highest social capital decile groups reduced significantly for complications (12.77% versus 12.11%, OR=1.06 P=0.04), the differences in mortality rates collapsed, and differences in readmission rates remained insignificant. These data suggest that Medicare beneficiaries who live in communities with lower social capital are more likely to undergo unplanned surgery for access-sensitive conditions. Efforts to improve social capital in these communities may be one strategy for reducing the rate of unplanned operations.