Presence Of Abdominal Aortic Aneurysm Research Articles

Abstract 293: ApoB-Containing Lipoproteins Contribute to Augmentation of AngII-Induced Abdominal Aortic Aneurysms

Background and objective: Presence of abdominal aortic aneurysms (AAA) is associated with dyslipidemia in humans. Hypercholesterolemic mice having a predominance of ApoB-containing lipoproteins are more susceptible to Angiotensin (Ang)II-induced AAA formation. A recent publication demonstrated that exogenously delivered high-density lipoprotein (HDL) prevented AngII-induced AAAs. ApoAI is the major apolipoprotein of HDL. The purpose of this study was to determine whether manipulations of ApoAI or ApoB-containing lipoproteins influence the development of AngII-induced AAA. Methods and Results: Eight week old male ApoAI +/+ or -/- mice with either wild type or LDL receptor -/- background were fed normal diet and infused with AngII (1 mg/kg/min) for 28 days. Plasma lipoprotein distributions were resolved by size exclusion gel chromatography. Deficiency of ApoAI led to profound reductions of plasma HDL-C concentrations in both strains. However, ApoAI deficiency did not exacerbate AngII-induced AAA as determined by maximal outer widths of suprarenal aortas (ApoAI +/+ versus -/-:1.52 ± 0.25 versus 1.22 ± 0.18 mm, P= 0.2 for C57BL/6 strain;1.21 ± 0.18 versus 1.11 ± 0.17 mm, P= 0.2 for LDLR -/- strain). Ezetimibe, an intestinal cholesterol absorption inhibitor, was administered to eight week old male ApoE -/- mice fed normal diet. Ezetimibe decreased plasma cholesterol concentrations from 451 ± 8 to 204 ± 18 mg/dl (P<0.001). This reduction was due to reductions in ApoB-containing lipoproteins. Administration of ezetimibe decreased AngII-induced AAA (control versus ezetimibe: 2.25 ± 0.28 mm versus 1.37 ± 0.1 mm, P=0.009). The same dose of ezetimibe was also administered to ApoE -/- mice fed western diet. Plasma cholesterol concentrations were reduced (from 980 ± 86 to 546 ± 11 mg/dl, P<0.001) attributed to reductions of apoB-containing lipoproteins. Administration of ezetimibe led to a profound reduction of atherosclerosis in western diet fed apoE -/- mice, but did not attenuate AngII-induced AAAs. Conclusion: ApoB-containing lipoproteins, rather than HDL, contribute to the augmentation of AngII-induced AAAs. However, substantial reductions in apoB-containing lipoproteins were required to attenuate AngII-induced AAA.

Association between seven single nucleotide polymorphisms involved in inflammation and proteolysis and abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) formation involves an inflammatory and proteolytic process. Previous studies suggest that AAA is a multifactorial disease with a strong genetic background. This study evaluated the role of seven important functional single nucleotide polymorphisms (SNPs) in AAA. This was a case-control study of two independent populations: 397 AAA patients (mean aortic diameter, 6.2 ± 1.4 cm) and 393 controls (mean diameter, 2.4 ± .2 cm) recruited from Greece (the main cohort), and 400 patients (mean diameter: 5.4 ± 1 cm) and 400 controls (mean diameter, 2.4 ± .6 cm) recruited from the United Kingdom (replication cohort). The functional SNPs analyzed were rs3025058, rs3918242, rs2276109, rs1801133, rs1799752, rs1799983, and rs16874954. These regulate the following enzymes: matrix metalloproteinases (MMPs), angiotensin-converting enzyme, endothelial nitric oxide synthase, methylenetetrahydrofolate reductase (MTHFR), and platelet-activating factor acetylhydrolase or lipoprotein-associated phospholipase A2. Genotype distributions (univariate analyses) did not differ significantly between cases and controls in the main or the replication cohort, with the exception of the MMP-3 rs3025058 SNP, where differences were borderline significant (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.02-1.97; P = .04) in the replication cohort. Adjusted analyses for age, sex, smoking, hypertension, and hypercholesterolemia disclosed no differences in either cohort. For SNPs that had previously been associated with AAA presence, meta-analysis of currently available data together with the two study cohorts disclosed positive associations for the MMP-3 rs3025058 (OR, 1.15; 95% CI, 1.06-1.25; P = .0009) and MTHFR rs1801133 (OR, 1.07; 95% CI, 1.02-1.12; P = .0088). The SNPs included in this analysis were not associated with AAA presence in either study population. However, meta-analysis of the currently available data disclosed a positive association for MMP-3 rs3025058 and MTHFR rs1801133.

Comparison of the Serum Lipidome in Patients With Abdominal Aortic Aneurysm and Peripheral Artery Disease

Currently, the relationship between circulating lipids and abdominal aortic aneurysm (AAA) is unclear. We conducted a lipidomic analysis to identify serum lipids associated with AAA presence. Secondary analyses assessed the ability of models incorporating lipidomic features to improve stratification of patient groups with and without AAA beyond traditional risk factors. Serum lipids were profiled via liquid chromatography tandem mass spectrometry analysis of serum from 161 patients with AAA and 168 controls with peripheral artery disease. Binary logistic regression was used to identify AAA-associated lipids. Classification models were created based on a combination of (1) traditional risk factors only or (2) lipidomic features and traditional risk factors. Model performance was assessed using receiver operator characteristic curves. Three diacylglycerols and 7 triacylglycerols were associated with AAA. Combining lipidomic features with traditional risk factors significantly improved stratification of AAA and peripheral artery disease groups when compared with traditional risk factors alone (mean area under the receiver operator characteristic curve [95% confidence interval], 0.760 [0.756-0.763] and 0.719 [0.716-0.723], respectively; P<0.05). A group of linoleic acid containing triacylglycerols and diacylglycerols were significantly associated with AAA presence. Inclusion of lipidomic features in multivariate analyses significantly improved prediction of AAA presence when compared with traditional risk factors alone.

Risk factors of recurrent ischemic colitis: a multicenter retrospective study.

Recurrence of ischemic colitis (IC) has not been studied extensively. The aim of this study was to investigate the characteristics of recurrent IC in the community setting and to identify any risk factors. We conducted a retrospective study in two community hospitals. Medical records of patients with IC from January 2007 to January 2013 were reviewed. Demographic details, clinical features, co- morbidities, concomitant use of medications,laboratory studies, imaging findings, endoscopic and histological features, surgery, hospital stay, and death within 30 days were collected. Patients were divided into two groups (recurrent IC group, non-recurrent IC group). A total of 118 patients with IC were identified. IC recurred in 10 patients (8.5%) during the study period. Half of the patients in the recurrent IC group were current smokers as compared to only 18.7% of patients in the non-recurrent group. In the recurrent IC group, 20.0% of patients never smoked as compared to 61.7% in the non-recurrent group (p=0.027).Abdominal aortic aneurysm (AAA) was more frequent in the recurrent IC group (40.0% vs. 4.7%; p=0.003). No differences in other clinical symptoms, CT scan findings, comorbidities, endoscopic features, or use of concomitant medications were observed between the two groups. The need for surgical intervention, blood transfusion, intensive care unit stay, mechanical ventilation,length of hospital stay, and anatomic location of affected segments did not differ between the two groups. IC recurred in 8.5% of patients during the six-year study period. Current smoking status and presence of AAA were identifying risk factors for recurrence of IC.

From tissue iron retention to low systemic haemoglobin levels, new pathophysiological biomarkers of human abdominal aortic aneurysm

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.

Treatment of Abdominal Aortic Aneurysms with Accompanied Iliac Artery Aneurysms Using New Sack Sealing Device

Summary Introduction. 20-30% of abdominal aortic aneurysms (AAA) occur simultaneously with unilateral or bilateral common iliac artery aneurysms (CIAA). Endovascular aneurysm repair (EVAR) is known to be an effective AAA treatment method used by many centres in over 80% of cases. Presence of AAA accompanied by CIAA significantly increases the complexity of EVAR with currently available endografts, internal iliac artery (IIA) often requiring coil embolisation resulting in serious post-procedural complications such as ischaemia of pelvic organs, gluteal claudication and erectile dysfunction. Aim of the study. Demonstrate successful endovascular AAA and CIAA treatment with new generation sac-sealing endograft device. Materials and methods. From 2008 Pauls Stradins Clinical University Hospital is participating in the prospective clinical trial assessing the efficacy and stability of the new generation sac-sealing endograft device (Nellix®, Endologix, USA). Until now this trial had 40 enrolled patients with suitable for endovascular treatment aneurysmal morphology. The treatment group has included 16 patients with AAA extending to either one or both common iliac arteries (CIA). The control group consisted of 24 patients with isolated AAA. AAA diameter was 5.6±0.76 cm (min - 4.3, max - 6.98) and 5.16± 0.91 cm (min-3.78, max-7.24) in the treatment and control groups respectively. Seven patients had unilateral and nine patients had bilateral CIAA. The diameter of CIAA was 2.61±0.57 cm (min - 2.04, max - 4.44). Post-procedural follow-up was done at one, six and twelve months and on annual basis thereafter. During follow-up the general health condition of the patients was assessed as well as computer tomography angiography (CTA) and duplex ultrasonography (DUS) imaging was performed in order to examine the status of the aneurysm, endograft condition and patency of IIA. Statistical analysis of data was performed using v19.0 SPSS software (IBM). Results. All patients successfully treated with new generation sac-sealing endograft excluding AAA and CIAA from blood circulation. Average follow-up period was 18 months. Upon follow-up in both groups endograft was stable and fixated in aneurysms with no endoleaks detected. In the treatment group all treated IIAs had remained patent with no pelvic organs ischaemia or gluteal claudication symptoms. Conclusion. New generation sac-sealing endograft is effective and simple in employment for the treatment of concomitant AAA and CIAA allowing the treatment of aneurysms with complex morphology and preserving the blood flow to internal iliac arteries. Further studies are required for long-term assessment of this endograft efficacy.

C-reactive protein polymorphism rs3091244 is associated with abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) formation involves an inflammatory process with a strong genetic background. C-reactive protein (CRP) regulates inflammation and is elevated in patients with AAA. The aim of this study was to investigate the association of the triallelic (C, A, and T alleles) rs3091244 functional CRP single nucleotide polymorphism (SNP) with AAA. This was a case-control study involving two independent populations: 351 AAA patients (mean aortic diameter, 6.25± 1.47cm) and 391 controls (mean diameter, 2.4± 0.2cm) were recruited from Greece (the main cohort); and 371 patients (mean diameter, 5.4± 1.0cm) and 362 controls (mean diameter, 2.4± 0.6cm) were recruited from the United Kingdom (replication cohort). The frequency of the functional triallelic (C, T, and A alleles) rs3091244 polymorphism was analyzed in univariate and adjusted (for cardiovascular risk factors) analyses, assuming that the rare T and A alleles have similar functional properties (pooled analysis for T and A). Three groups were constructed: group A included those with the rare T and A alleles (genotypes TT, AA, and TA), group B included heterozygotes for the C allele (CT, CA), and group C included C allele homozygotes (CC, reference genotype). Finally, meta-analysis of the two populations was performed together with previously reported results. Genotype distributions differed significantly between cases and controls in both cohorts (P< .001 and P= .001). Adjusted analysis (for all aneurysm-related risk-factors) showed an estimated odds ratio of 4.88 (95% confidence interval [CI], 2.96-8.04) for SNP group A and 2.38 (95% CI, 1.69-3.36) for SNP group B (P< .001 in both cases) in the initial cohort and 2.07 (95% CI, 1.33-3.21) for SNP group A and 1.70 (95% CI, 1.21-2.39) for SNP group B (P= .001 and .002) in the replication cohort. The SNP group A patients among the main cohort also had higher CRP levels (median, 26; interquartile range, 17-52mg/L vs median, 4; interquartile range, 4-12mg/L; P< .001). Aneurysms >5.5cm were significantly more frequent among the SNP groups A and B compared with C allele homozygotes both in the main and the replication cohorts (P< .001 and P= .001, respectively). Meta-analysis of the two populations with previously reported results showed a positive association between minor-allele and aneurysm presence with an odds ratio of 1.47 (95% CI, 1.01-2.14; I(2)= 83.1%; P= .04). The rare T and A alleles were significantly related with AAA presence in both populations and correlated with higher CRP levels and AAA diameter.

Severity of Coronary Artery Disease is Associated with Prevalence of Abdominal Aortic Aneurysm; Use of Complex Scoring Systems for Severity of Coronary Artery Disease Does not Demonstrate a Significant Staged Association with AAA Prevalence

Background: Presence of abdominal aortic aneurysm (AAA) is significantly associated with of other forms of atherosclerosis. This study examined the utility of complex scoring systems for the severity of coronary artery disease (CAD), compared to the presence of single, double, or triple vessel disease, to predict the likelihood of AAA in a series of patients undergoing coronary angiogram, with the aim to identify a potential target for New Zealand screening programmes.

Utilidad de la ecografía portátil en el cribado del aneurisma de aorta abdominal y de la ateromatosis de aorta abdominal

Background and objectiveTo determine the prevalence of abdominal aortic aneurysm (AAA) and abdominal aortic atheromatosis (AA-At) using a hand-held ultrasound by a general practitioner in the public Primary Health Care system. Patients and methodPilot study that prospectively studied a cohort of men over 50 years with cardiovascular risk factors: active smokers, former smokers, or hypertensive patients, attended in primary health care center. The general practitioner completed an ultrasonography training in an Ultrasound Unit under supervision of experienced radiologists using an standard ultrasound equipment and hand-held ultrasound (VScan®, General Electric, USA). One hundred and six patients participated in the study and all imaging data recorded were blindly evaluated by a radiologist in order to establish the concordance in the interpretation of images between general practitioner and radiologist. The kappa index was calculated to study the agreement on the presence or absence of AAA and AA-At. ResultsWe observed a prevalence of 5.88% of AAA. Kappa index for concordance in AAA diagnosis was absolute (κ=1.0), with a sensitivity and specificity of 100%. Otherwise, the general practitioner identified 59 patients (58.4%) with AA-At, while radiologist identified 39 (38.6%) in the image review, with moderate concordance (κ=.435), sensitivity 89.74% and specificity 57.14%. Hypercholesterolemia (odds ratio [OR] 2.61; 95% confidence interval [95% CI] 0.92-7.39) and diabetes mellitus (OR 3.35; 95%CI 0.89-12.55) were independent risk factors for AA-At development in logistic regression. ConclusionsAfter an adequate training in ultrasonography, hand-held ultrasound is a useful tool for AAA screening in Primary Care. Its simplicity, security, validity, cost-effectiveness and acceptance by the general population, makes it a feasible tool for cardiovascular risk assessment.

Plasma total homocysteine is associated with abdominal aortic aneurysm and aortic diameter in older men

This study was conducted to determine whether plasma total homocysteine (tHcy) and the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism are associated with abdominal aortic aneurysm (AAA) and aortic diameter. This was a cross-sectional study set in Western Australia of 4248 community-dwelling men aged 70 to 88 years. Infrarenal aortic diameter was measured using ultrasound scan, tHcy was measured by immunoassay, and MTHFR 677T polymorphism was detected by polymerase chain reaction. Adjusted multinomial logistic regression analysis showed the odds of having an AAA (aortic diameter ≥ 30 mm) for men with high tHcy (≥ 15 μmol/L) compared with those with normal tHcy (<15 μmol/L) was 1.45 (95% confidence interval [CI], 1.10-1.91). Every 5-μmol/L increment in tHcy was associated with 0.15-mm (95% CI, 0.01-0.28 mm) increase in mean aortic diameter. The tHcy concentration was higher in MTHFR TT homozygote individuals than in wild-type CC individuals. There was, however, no apparent association between MTHFR C677T polymorphism with AAA (TT vs CC genotype: odds ratio, 0.97; 95% CI, 0.72-1.31) or aortic diameter (TT vs CC genotype: mean increment of 0.01 mm; 95% CI, -0.63 to 0.65 mm). Elevated tHcy is associated with the presence of AAA in older men. There is also a positive dose-response relationship between tHcy and abdominal aortic diameter. Longitudinal studies and clinical trials of lowering tHcy are required to assess whether these relationships are causal.

Abstract 240: Serum Cholesterol and Angiotensin-Induced Abdominal Aortic Aneurysm in Hypercholesterolemic Mice

Background Although hyperlipidemia is known to augment the incidence of abdominal aortic aneurysms (AAA) in the AngII-induced model of apolipoprotein E -/- mice, its relationship to AAA size is unknown. Therefore, we evaluated the relationship between total cholesterol concentration (TC) and change (delta) in aortic diameter. Methods TC was measured in 36 male mice that underwent a 4-week infusion period with saline (n=9) or AngII (1500 ng/kg/min; n=27), along with serial measurements of pulse rate (PR), and pulse (PP), mean arterial (MAP), systolic (SBP) and diastolic (DBP) pressure. A linear mixed effect model was used to assess the relationship between all hemodynamic parameters and delta. Nonparametric and linear regression methods were used to evaluate TC in relation to delta. Results TC did not differ between AngII and control mice (Figure, bottom left) (p=0.18). The burden of atherosclerosis was greater among AngII-exposed mice versus control, but did not differ by presence or size of AAA (Figure, bottom right). None of the hemodynamic parameters were predictive of delta (SBP, p = 0.66; DBP, p = 0.66; MAP, p = 0.55; PP, p = 0.66; and PR, p = 0.39). Mean TC was higher among mice with large versus small AAA (552.6 vs. 393.5 mg/ ml, p&lt;0.05; Figure, top right). The nonparametric smoothing line (Figure, top left) suggests a first order relationship between delta and TC (p for trend &lt; 0.001). AngII (ß = 0.48, p &lt; 0.001) and TC (ß = 0.0015, p = 0.003) were independent predictors in the linear model for delta. Conclusions Our findings suggest that TC is incrementally associated with AAA size. These findings may have potential clinical relevance for risk assessment in AAA patients. Figure

Is Hypovitaminosis D Associated with Abdominal Aortic Aneurysm, and is There a Dose–response Relationship?

This study aims to investigate the association between plasma 25-hydroxyvitamin D (25(OH)D) concentrations with the presence of abdominal aortic aneurysm (AAA) and aortic diameter. An observational study of 4233 community-dwelling men aged 70-88 years, who participated in a randomised controlled trial of screening for AAA. Infrarenal aortic diameter measured by ultrasound and 25(OH)D by immunoassay. A total of 311 men (7.4%) with AAA (defined as aortic diameter ≥ 30 mm) comprised the study. Multivariable models were adjusted for age, smoking, cardiovascular disease, hypertension, diabetes, dyslipidaemia, body mass index and serum creatinine concentration. Amongst men with the lowest 25(OH)D quartile of values compared with the highest quartile, the adjusted odds ratio of having an AAA increased in a graded fashion from 1.23 (95% confidence interval (CI) 0.87-1.73) for AAA ≥ 30 mm to 5.42 (95% CI 1.85-15.88) for AAA ≥ 40 mm. Similarly, there was a dose-response relationship between 25(OH)D concentrations and the size of the AAA: every 10-nmol l(-1) decrease in 25(OH)D levels was associated with 0.49 mm (95% CI 0.11-0.87) increase in mean aortic diameter. Low vitamin D status is associated with the presence of larger AAA in older men, and there is a graded inverse relationship between 25(OH)D concentrations and AAA diameter. Further research is needed to clarify the mechanisms underlying these associations.

Systematic Review: Emergency Department Bedside Ultrasonography for Diagnosing Suspected Abdominal Aortic Aneurysm

The use of ultrasound (US) to diagnose an abdominal aortic aneurysm (AAA) has been well studied in the radiology literature, but has yet to be rigorously reviewed in the emergency medicine arena. This was a systematic review of the literature for the operating characteristics of emergency department (ED) ultrasonography for AAA. The authors searched PubMed and EMBASE databases for trials from 1965 through November 2011 using a search strategy derived from the following PICO formulation: Patients-patients (18+ years) suspected of AAA. Intervention-bedside ED US to detect AAA. Comparator-reference standard for diagnosing an AAA was a computed tomography (CT), magnetic resonance imaging (MRI), aortography, official US performed by radiology, ED US reviewed by radiology, exploratory laparotomy, or autopsy results. AAA was defined as ≥ 3 cm dilation of the aorta. Outcome-operating characteristics (sensitivity, specificity, and likelihood ratios [LR]) of ED abdominal US. The papers were analyzed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) guidelines. The initial search strategy identified 1,238 articles; application of inclusion/exclusion criteria resulted in seven studies with 655 patients. The weighted average prevalence of AAA in symptomatic patients over the age of 50 years is 23%. On history, 50% of AAA patients will lack the classic triad of hypotension, back pain, and pulsatile abdominal mass. The sensitivity of abdominal palpation for AAA increases as the diameter of the AAA increases. The pooled operating characteristics of ED US for the detection of AAA were sensitivity 99% (95% confidence interval [CI] = 96% to 100%) and specificity 98% (95% CI = 97% to 99%). Seven high-quality studies of the operating characteristics of ED bedside US in diagnosing AAA were identified. All showed excellent diagnostic performance for emergency bedside US to detect the presence of AAA in symptomatic patients.

212: Death and cardiovascular events in patients with acute coronary syndrome and abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is associated with peripheral and coronary artery disease (CAD), however little is known about the prognosis of patients who experienced an acute coronary syndrome (ACS) and have an AAA. The aim of this study was to assess the prevalence of AAA in patients hospitalized for ACS and to evaluate it was associated with an increased cardio-vascular (CV) risk during follow up. Between February 1, 2008 and March 30, 2009, patients admitted for ACS with significant (≥50% stenosis) coronary lesions underwent echography to check for presence of AAA. The AAA was defined as dilation of infrarenal aorta with maximum antero-posterior diameter ≥30 mm. During a 2 years follow-up we recorded all causes death, CV death and non-fatals CV events. The combination of CV death and CV non-fatals events was defined as the primary endpoint. Among 306 patients, 20 AAAs (6,6%) were diagnosed, of average (±sd) diameter 33±3.7 mm, with a maximum diameter of 45 mm, non requiring surgery. Follow-up at 2 years was available for 292 patients (95,7%). During follow-up, 77 patients (25,5%) experienced an event (all causes death or non-fatals CV event) : 23 deaths (7,6%), of wich 16 were from CV cause, and 55 non-fatals CV event (18,2%). No event was due to AAA. In univariate analysis age, abdominal aortic diameter, diabetes mellitus, previously known CAD and AAA were significantly associated with fatal and non-fatal CV event (p<0,05). In multivariate analysis, age (OR=1.03; 95%CI (1.008,1.058), diabetes mellitus (OR=1.7; 95%CI (1.05,2.7) and AAA (OR=3.2; 95%CI (1.24,8.44) were independantly associated with the risk of fatal or non-fatal CV event. Age (OR=1.18 95%CI (1.10,1.26) and AAA (OR=4.17 95%CI (1.17,14.9) were the only independant predictors of all causes death. Our results show that in patients with CAD, the presence of small non surgical AAA is associated with worse CV prognosis and higher all causes mortality at 2 years.

MMP-9: biomarker for abdominal aneurysm.

Matrix Metalloproteinase 9 (MMP-9) has been shown to express significantly on organ tissue culture in Abdominal Aortic Aneurysm (AAA) patients. Prior studies have shown the correlation between MMP-9 concentration levels with AAA raising the probability of its usage as a biomarker in AAA disease. However, results of previous studies have been conflicting. The purpose of this study is to identify the correlation between MMP-9 concentration levels with AAA disease and further define the utility as a biomarker for our center population. This is prospective controlled trial. Peripheral venous blood sample is obtained from 20 patients with AAA and 36 normal control subjects. MMP-9 concentration levels were determined by an enzyme-linked immunosorbent assay and compared with subjects abdominal ultrasonography or computed tomography of abdomen. Mean (± SE) MMP-9 was 23.94 ± 0.60 ng/mL in normal control subjects and 21.39 ± 1.03 ng/mL in patients with AAAs (p ← 0.05 versus normal control subjects). MMP-9 correlate significantly with AAA (p=0.004). There was no correlation of MMP-9 levels with age, gender, or other risk factors. The cutoff point is 12.54 for aorta size <3.0 cm. The sensitivity and specificity of MMP-9 were 60% and 64% respectively. MMP-9 levels correlate significantly with AAA with a cutoff point of 12.54. However, the utility of MMP-9 as a diagnostic test is limited due to low sensitivity and specificity. An elevated MMP-9 has limited use to predict the presence of AAA (positive predictive value: 60%) and a normal MMP-9 level was insufficient to determine the absence of AAA (negative predictive value: 36.1%).

A gene-centric study of common carotid artery remodelling

BackgroundExpansive remodelling is the process of compensatory arterial enlargement in response to atherosclerotic stimuli. The genetic determinants of this process are poorly characterized. MethodsGenetic association analyses of inter-adventitial common carotid artery diameter (ICCAD) in the IMPROVE study (n = 3427) using the Illumina 200k Metabochip was performed. Single nucleotide polymorphisms (SNPs) that met array-wide significance were taken forward for analysis in three further studies (n = 5704), and tested for association with Abdominal Aortic Aneurysm (AAA). Resultsrs3768445 on Chromosome 1q24.3, in a cluster of protein coding genes (DNM3, PIGC, C1orf105) was associated with larger ICCAD in the IMPROVE study. For each copy of the rare allele carried, ICCAD was on average 0.13 mm greater (95% CI 0.08–0.18 mm, P = 8.2 × 10−8). A proxy SNP (rs4916251, R2 = 0.99) did not, however, show association with ICCAD in three follow-up studies (P for replication = 0.29). There was evidence of interaction between carotid intima-media thickness (CIMT) and rs4916251 on ICCAD in two of the cohorts studies suggesting that it plays a role in the remodelling response to atherosclerosis. In meta-analysis of 5 case–control studies pooling data from 5007 cases and 43,630 controls, rs4916251 was associated with presence of AAA 1.10, 95% CI 1.03–1.17, p = 2.8 × 10−3, I2 = 18.8, Q = 0.30). A proxy SNP, rs4916251 was also associated with increased expression of PIGC in aortic tissue, suggesting that this may the mechanism by which this locus affects vascular remodelling. ConclusionsCommon variation at 1q24.3 is associated with expansive vascular remodelling and risk of AAA. These findings support a hypothesis that pathways involved in systemic vascular remodelling play a role in AAA development.

Arterial stiffness and novel biomarkers in patients with abdominal aortic aneurysms

ObjectivesPulse wave velocity (PWV) constitutes a valid index of arterial stiffness osteoprotegerin (OPG) and osteopontin (OPN) which are well-established vascular calcification inhibitors, highly correlated with inflammation, and cardiovascular events incidence. We investigated the association of PWV with the aforementioned novel biomarkers in patients with abdominal aortic aneurysm (AAA). MethodsWe enrolled 108 men with AAA (AAA group) candidates for endovascular repair. We excluded patients with Marfan syndrome or other collagen-related disorders. Forty-one age-matched men, with stable coronary artery disease (CAD), but without AAA, served as controls (CO group). PWV, clinical parameters and serum levels of osteoprotegerin (OPG), osteopontin (OPN), interleukin-6 (IL-6) and IL-10 were determined. ResultsWith the exception of higher smoking rate and the lower statin's usage in the AAA group, there were non-significant differences in the rest of demographic and clinical parameters (p>0.05). We found significantly higher levels of PWV in AAA than CO group (12.99±3.75m/s vs 10.03±1.57m/s, p<0.001). In parallel, serum OPG, OPN, IL-6 levels were considerably increased, while IL-10 levels were downregulated (p<0.001) in AAA group. PWV positively correlated with mean blood pressure, OPG concentrations and AAA diameter in univariate and multivariate analysis (R2=0.498, p=0.008). Finally, age and OPG remained independent determinants of AAA presence in the whole study cohort. ConclusionsArterial stiffness, circulating vascular calcification inhibitors and inflammatory mediators seem to be significantly upregulated in patients with AAA. An independent association of PWV with mean blood pressure, OPG and AAA diameter is of clinical importance which requires further investigation.

How the Dissection Laboratory Facilitates Integration of Learning: Presence of Abdominal Aortic Aneurysm with a Large Intracardiac Thrombus: A Rare Cadaver Finding

There is a debate among medical education experts on the application of dissection or prosection for learning anatomy. However, the literature reveals that the majority of published articles are in favor of dissection. In this article, we present a case of an abdominal aortic aneurysm (AAA) with intracardiac thrombus in a cadaver on routine dissection. We will discuss possible explanations for such finding and provide some insight into how this finding can support the significance of the cadaver-based teaching of anatomy of the medical students. Initially, the abdomen was dissected and exposed to study the abdominal structures in an anatomy class and later the thoracic region was dissected and all the clinical abnormalities were examined and documented. Autopsy of the clot was obtained for histopathology analysis. The intracardiac thrombus was present in the right atrium characterized by its projection into the superior vena cava, inferior vena cava, and the right ventricle. The AAA was extensive and inferior to the renal arteries constricting the entire inferior vena cava. Moreover, associated findings included presence of numerous collaterals in the thoracic region near the superior vena cava; histological examination of the clot showed extensive population of leukocytes. There were enlarged mediastinal lymph nodes. Our cadaver showed an excellent model for integrating between clinical anatomy and pathology by triggering medical students to think of normal and abnormal structures: often called "thinking outside the box." Such an effort might help them in developing their thought processes and future medical careers.

Prevalence and Early Detection of Abdominal Aortic Aneurysm in Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma

Purpose: The goals of this study were to demonstrate the frequency of infrarenal abdominal aortic aneurysm (AAA) in patients with pseudoexfoliation (PEX) syndrome (PEXS) and PEX glaucoma (PEXG), and to determine whether limited screening for AAA in specific subgroups of patients with PEX is reasonable and justifiable.Materials and Methods: This prospective study comprised 60 patients with PEXS and 60 with PEXG (examined group), and 60 patients with primary open-angle glaucoma (POAG) and 60 with cataract (control group). Clinical ophthalmic examination included slit-lamp biomicroscopy of the anterior segment and direct slit-lamp gonioscopy (using a Goldmann three-mirror lens) of the anterior chamber angle. All patients underwent routine Color Doppler duplex ultrasonography of the infrarenal aorta and iliac arteries.Results: There was a statistically significant difference (p < 0.05) between the PEXG group and control group vis-a-vis presence of AAA, which occurred more frequently in patients with greater amounts of angle pigmentation (p < 0.05). Univariate logistic regression analysis indicated statistically significant associations between AAA and PEX (p < 0.01), angle pigmentation (p < 0.05), gender (p < 0.01), diabetes mellitus (DM) (p < 0.05), and arterial hypertension (AHT) (p < 0.01). Multivariate regression analysis, adjusted to gender and age, showed that the most important clinical parameters related to AAA in patients with PEXS and PEXG are gender, presence of PEX, DM, and AHT (p < 0.05).Conclusion: The frequency of AAA is significantly higher in patients with PEXS and PEXG than in patients with POAG or cataract. Restricted screening for AAA in male PEXS patients, who also have elevated degrees of angle pigmentation, arterial hypertension, and DM, is clinically warranted.

Long term outcomes in men screened for abdominal aortic aneurysm: prospective cohort study

Objective To determine whether there is a relation between aortic diameter and morbidity and mortality in men screened for abdominal aortic aneurysm.Design Prospective cohort study.Setting Highland and Western Isles (a...