Benefits and harms of screening men for abdominal aortic aneurysm in Sweden: a registry-based cohort study

Abdominal aortic calcium and geometry in patients with essential hypertension

PURPOSE

Abdominal aorta calcium (AAC) burden and dilatation are associated with an increased risk of mortality. The purpose of this study was to investigate determinants of AAC and abdominal aorta size in patients with essential hypertension.

MATERIALS AND METHODS

Patients with uncomplicated essential hypertension who had undergone non-enhanced abdominal CT to rule out secondary hypertension in addition to biological test were recruited between 2010 and 2018. A semi-automatic system was designed to estimate the aortic size (diameter, length, volume) and quantify the AAC from mesenteric artery to bifurcation using the Agatston score. Determinants of aortic size and those related to AAC were searched for using uni- and multivariables analyses.

RESULTS

Among 293 randomly selected patients with hypertension (age 52 ± 11 [SD] years) included, 23% had resistant hypertension. Mean abdominal aorta diameter was 20.1 ± 2.1 (SD) mm. Eight (3%) patients had abdominal aorta aneurysm ≥ 30 mm and 58 (20%) had dilated abdominal aorta ≥ 27 mm. Median AAC score was 38 and calcifications were detected in the infra- and supra-renal abdominal aortic portions in 59% and 26% of the patients, respectively. After adjustment for age, male sex and body surface area, abdominal aorta diameter was positively associated with diastolic blood pressure (P = 0.0019). Smoking was the single variable associated with calcified abdominal aorta (P < 0.001) after adjustment for cofactors. In patients with calcifications of abdominal aorta, the score increased with smoking history (P < 0.001), statins treatment (P < 0.01), greater number of anti-hypertensive drugs (P < 0.01), larger abdominal aorta (P < 0.05) and greater systolic blood pressure (P < 0.05). Patients with resistant hypertension had more AAC in the supra-renal abdominal aorta portion than those without resistant hypertension (P < 0.01).

CONCLUSION

In patients with essential hypertension, abdominal aorta dilation is related with diastolic blood pressure while AAC is associated with smoking history and resistant hypertension when located to the supra-renal abdominal aorta portion.

Non-coronary arterial outcomes in people with type 1 diabetes mellitus: a Swedish retrospective cohort study

Background

Observational studies on long-term trends, risk factor association and importance are scarce for type 1 diabetes mellitus and peripheral arterial outcomes. We set out to investigate trends in non-coronary complications and their relationships with cardiovascular risk factors in persons with type 1 diabetes mellitus compared to matched controls.

Methods

34,263 persons with type 1 diabetes mellitus from the Swedish National Diabetes Register and 164,063 matched controls were included. Incidence rates of extracranial large artery disease, aortic aneurysm, aortic dissection, lower extremity artery disease, and diabetic foot syndrome were analyzed using standardized incidence rates and Cox regression.

Findings

Between 2001 and 2019, type 1 diabetes mellitus incidence rates per 100,000 person-years were as follows: extracranial large artery disease 296.5-84.3, aortic aneurysm 0-9.2, aortic dissection remained at 0, lower extremity artery disease 456.6-311.1, and diabetic foot disease 814.7-77.6. Persons with type 1 diabetes mellitus with cardiometabolic risk factors at target range did not exhibit excess risk of extracranial large artery disease [HR 0.83 (95% CI, 0.20-3.36)] or lower extremity artery disease [HR 0.94 (95% CI, 0.30-2.93)], compared to controls. Persons with type 1 diabetes with all risk factors at baseline, had substantially elevated risk for diabetic foot disease [HR 29.44 (95% CI, 3.83-226.04)], compared to persons with type 1 diabetes with no risk factors. Persons with type 1 diabetes mellitus continued to display a lower risk for aortic aneurysm, even with three cardiovascular risk factors at baseline [HR 0.31 (95% CI, 0.15-0.67)]. Relative importance analyses demonstrated that education, glycated hemoglobin (HbA1c), duration of diabetes and lipids explained 54% of extracranial large artery disease, while HbA1c, smoking and systolic blood pressure explained 50% of lower extremity artery disease and HbA1c alone contributed to 41% of diabetic foot disease. Income, duration of diabetes and body mass index explained 66% of the contribution to aortic aneurysm.

Interpretation

Peripheral arterial complications decreased in persons with type 1 diabetes mellitus, except for aortic aneurysm which remained low. Besides glycemic control, traditional cardiovascular risk factors were associated with incident outcomes. Risk of these outcomes increased with additional risk factors present. Persons with type 1 diabetes mellitus exhibited a lower risk of aortic aneurysm compared to controls, despite presence of cardiovascular risk factors.

Funding

Swedish Governmental and the county support of research and education of doctors, the Swedish Heart and Lung Foundation, Sweden and Åke-Wibergs grant.

Evidence for overdiagnosis in noncancer conditions was assessed: a metaepidemiological study using the 'Fair Umpire' framework

OBJECTIVES

To evaluate the strength of the evidence for, and the extent of, overdiagnosis in noncancer conditions.

STUDY DESIGN AND SETTING

We systematically searched for studies investigating overdiagnosis in noncancer conditions. Using the 'Fair Umpire' framework to assess the evidence that cases diagnosed by one diagnostic strategy but not by another may be overdiagnosed, two reviewers independently identified whether a Fair Umpire-a disease-specific clinical outcome, a test result or risk factor that can determine whether an additional case does or does not have disease-was present. Disease-specific clinical outcomes provide the strongest evidence for overdiagnosis, follow-up or concurrent tests provide weaker evidence, and risk factors provide only weak evidence. Studies without a Fair Umpire provide the weakest evidence of overdiagnosis.

RESULTS

Of 132 studies, 47 (36%) did not include a Fair Umpire to adjudicate additional diagnoses. When present, the most common Umpire was a single test or risk factor (32% of studies), with disease-specific clinical outcome Umpires used in only 21% of studies. Estimates of overdiagnosis included 43-45% of screen-detected acute abdominal aneurysms, 54% of cases of acute kidney injury, and 77% of cases of oligohydramnios in pregnancy.

CONCLUSION

Much of the current evidence for overdiagnosis in noncancer conditions is weak. Application of the framework can guide development of robust studies to detect and estimate overdiagnosis in noncancer conditions, ultimately informing evidence-based policies to reduce it.

Association between the non-HDL-cholesterol to HDL- cholesterol ratio and abdominal aortic aneurysm from a Chinese screening program

BACKGROUND

Abdominal aortic aneurysms (AAAs) can result in high mortality upon rupture but are usually undiagnosed because of the absence of symptoms in the early stage. Ultrasound screening is regarded as an impactful way to prevent the AAA-related death but cannot be performed efficiently; therefore, a target population, especially in Asia, for this procedure is lacking. Additionally, although dyslipidaemia and atherosclerosis are associated with AAA. However, it remains undetermined whether the non-high-density lipoprotein-cholesterol to high-density lipoprotein-cholesterol ratio (NHHR) is associated with AAA. Therefore, this study was aimed at examining whether NHHR is associated with AAA.

METHOD

A total of 9559 participants who underwent AAA screening at Guangdong Provincial People's Hospital and through screening in two communities in Dongguan, from June 2019 to June 2021 joined in this screening program. The diagnosis of AAA was confirmed by the ultrasound examination of the abdominal aorta rather than any known or suspected AAA. Clinical and laboratory data of participants were collected. The participants were separated into a normal group and an AAA group according to the abdominal aortic status. To eliminate confounding factors, a propensity score matching (PSM) approach was utilized. The independent relationship between NHHR and AAA was assessed through the utilization of multivariable logistic regression analysis. In addition, internal consistency was evaluated through subgroup analysis, which controlled for significant risk factors.

RESULTS

Of all the participants, 219 (2.29%) participants were diagnosed with AAA. A significant elevation in NHHR was identified in the AAA group when contrasted with that in the normal group (P < 0.001). As demonstrated by the results of the multivariable logistic regression analysis, AAA was independently associated with NHHR before (odds ratio [OR], 1.440, P < 0.001) and after PSM (OR, 1.515, P < 0.001). Significant extension was observed in the areas under the receiver operating characteristic curves (AUROCs) of NHHR compared to those of single lipid parameters before and after PSM. An accordant association between NHHR and AAA in different subgroups was demonstrated by subgroup analysis.

CONCLUSION

In the Chinese population, there is an independent association between NHHR and AAA. NHHR might be propitious to distinguish individuals with high risk of AAA.

Data-driven overdiagnosis definitions: A scoping review

INTRODUCTION

Adequate methods to promptly translate digital health innovations for improved patient care are essential. Advances in Artificial Intelligence (AI) and Machine Learning (ML) have been sources of digital innovation and hold the promise to revolutionize the way we treat, manage and diagnose patients. Understanding the benefits but also the potential adverse effects of digital health innovations, particularly when these are made available or applied on healthier segments of the population is essential. One of such adverse effects is overdiagnosis.

OBJECTIVE

to comprehensively analyze quantification strategies and data-driven definitions for overdiagnosis reported in the literature.

METHODS

we conducted a scoping systematic review of manuscripts describing quantitative methods to estimate the proportion of overdiagnosed patients.

RESULTS

we identified 46 studies that met our inclusion criteria. They covered a variety of clinical conditions, primarily breast and prostate cancer. Methods to quantify overdiagnosis included both prospective and retrospective methods including randomized clinical trials, and simulations.

CONCLUSION

a variety of methods to quantify overdiagnosis have been published, producing widely diverging results. A standard method to quantify overdiagnosis is needed to allow its mitigation during the rapidly increasing development of new digital diagnostic tools.

Psychosocial consequences after screening of abdominal aortic aneurysm among 65 year old men

BACKGROUND

In order to reduce the incidence of abdominal aortic aneurysm rupture and mortality, the Swedish Medical Council has introduced a national abdominal aortic aneurysm (AAA) screening program that offers ultrasound examination of 65-year-old men. Screening programmes of AAA may confer both benefits and harms. The study aim was to investigate the psychosocial consequences of AAA screening among men with screening-detected AAA as compared to men identified as AAA-negative at screening, using an AAA-specific questionnaire.

METHODS

This cross-sectional study investigated the psychosocial consequences of AAA screening measured with a condition-specific questionnaire. This study focused on the Experience of the Diagnosis and the Screening Procedure in terms of Anxiety, Sense of Dejection and Existential Values. One hundred and fifty-eight men with AAA (63%) and 275 with normal aorta size (55%) completed the diagnosis-specific questionnaire.

RESULTS

Ninety-six percent of men with screening detected AAA did not regret the screening examination, the corresponding figure for controls being 99.6%. Seventy percent of AAA patients were surprised that something was wrong in their body. Some (85%) of men with AAA were current or previous smokers, about half of them (45%) felt guilty about it and 78% of the current smokers in the AAA group had considered stopping smoking. Both groups considered changing lifestyle, although at a higher rate (32%) among AAA cases than controls (20%), with differences both in intention to change their ways to exercise (p = 0.019) and food intake (p = 0.001). Intergroup differences were identified for the majority of items as captured by the questionnaire where men identified with AAA reported more negative psycho-social consequences for all evaluated items except for the items: Regret of the screening examination (p = 0.069) and feeling terrified (p = 0.10). Fifty-one percent of AAA cases stated that they feared rupture, and 12% were anxious about rupture during sexual activity whereas 57% were worried about rupture during intense physical activity.

CONCLUSION

Men who were diagnosed with AAA reported more psychosocial consequences compared to controls; still only a minority of AAA cases reported psychosocial consequences in greater occurrence. To some degree, men with AAA also feared rupture during various types of activities. There appears to be a need for improved patient information and easy access to caregivers for men with screening-detected AAA, which might help to reduce psychosocial consequences associated with the diagnosis.

Focus on the Most Common Paucisymptomatic Vasculopathic Population, from Diagnosis to Secondary Prevention of Complications

Middle-aged adults can start to be affected by some arterial diseases (ADs), such as abdominal aortic or popliteal artery aneurysms, lower extremity arterial disease, internal carotid, or renal artery or subclavian artery stenosis. These vasculopathies are often asymptomatic or paucisymptomatic before manifesting themselves with dramatic complications. Therefore, early detection of ADs is fundamental to reduce the risk of major adverse cardiovascular and limb events. Furthermore, ADs carry a high correlation with silent coronary artery disease (CAD). This study focuses on the most common ADs, in the attempt to summarize some key points which should selectively drive screening. Since the human and economic possibilities to instrumentally screen wide populations is not evident, deep knowledge of semeiotics and careful anamnesis must play a central role in our daily activity as physicians. The presence of some risk factors for atherosclerosis, or an already known history of CAD, can raise the clinical suspicion of ADs after a careful clinical history and a deep physical examination. The clinical suspicion must then be confirmed by a first-level ultrasound investigation and, if so, adequate treatments can be adopted to prevent dreadful complications.

Using red blood cell distribution width to predict death after abdominal aortic aneurysm rupture

BACKGROUND

An abdominal aortic aneurysm is a life-threatening enlargement in the major vessel at the abdomen level. This study investigated the associations between different levels of red blood cell distribution width and all-cause mortality among patients with abdominal aortic aneurysm rupture. It developed predictive models for all-cause mortality risk.

METHODS

This was a retrospective cohort study using 2001 to 2012 MIMIC-III dataset. The study sample included 392 U.S. adults with abdominal aortic aneurysms who were admitted to ICU after the aneurysm rupture. Then we used two single-factor and four multivariable logistic regression models to examine the associations between different levels of red blood cell distribution and all-cause mortality (30 days and 90 days), controlling for demographics, comorbidities, vital signs, and other laboratory measurements. The receiver operator characteristic curves were calculated, and the areas under the curves were recorded.

RESULTS

There were 140 (35.7%) patients with an abdominal aortic aneurysm in the red blood cell distribution width range between 11.7 and 13.8%, 117 (29.8%) patients in the range between 13.9 and 14.9%, and 135 (34.5%) patients in the range between 15.0 and 21.6%. Patients with higher red blood cell distribution width level (> 13.8%) tended to have a higher mortality rate (both 30 days and 90 days), congestive heart failure, renal failure, coagulation disorders, lower hemoglobin, hematocrit, MCV, red blood cell count, higher levels of chloride, creatinine, sodium, and BUN (All P < 0.05). Results of multivariate logistic regression models indicated that patients with higher red blood cell distribution width levels (> 13.8%) had the highest statistically significant odd ratios of 30 days and 90 days of all-cause mortality than lower red blood cell distribution width levels. The area under the RDW curve was lower (P = 0.0009) than that of SAPSII scores.

CONCLUSIONS

Our study found that patients with abdominal aortic aneurysm rupture with a higher blood cell distribution had the highest risk of all-cause mortality. Using the blood cell distribution width level in patients with abdominal aortic aneurysm rupture to predict mortality should be considered in future clinical practice.

Outcomes of a pilot abdominal aortic aneurysm screening program in a population of Central Greece

BACKGROUND

Abdominal aortic aneurysm (AAA) screening has contributed in the decrease of aneurysm related and all-cause mortality. The objective of our study is to present our experience from the only existing pilot AAA screening program in Greece.

METHODS

Men from both urban and rural areas in Central Greece, aged >60 years old without a previously known diagnosis of AAA were invited through the public primary health care units to participate to a screening program. Demographics, comorbidities, family history and anthropometric data were recorded. Aortic diameter values of >30 mm and common iliac artery (CIA) diameter values of >18 mm, were defined as aneurysmatic by ultrasound.

RESULTS

The screening program included 1256 individuals (1256/1814; response rate 69%). The incidence of AAA and CIA aneurysm was 2% (25/1256) and 2.3% (29/1256), respectively. Increased age (P<0.042), tobacco use (P<0.006) and its duration (P<0.008) were related to higher incidence of AAA, while diabetes mellitus to lower one (P<0.048). Multivariate analysis showed that AAA was associated to longer duration of smoking (1.05, CI: 0.02-6.6; P=0.01). Statin and antiplatelet therapy were administrated in 40% (10/25) and 44% (11/25), respectively of individuals with AAA. An additional analysis was provided between subjects with AD of 25-30 mm and AD <25 mm. In multivariate analysis, no factor was associated to AD of 25-30 mm.

CONCLUSIONS

The incidence of AAA and CIA aneurysm in Central Greece is 2% and 2.3%, respectively. Smoking duration was the strongest associated factor with AAA incidence. This provides to healthcare policy makers a strong valid point for the prevention strategies.

Projection of global burden and risk factors for aortic aneurysm - timely warning for greater emphasis on managing blood pressure

RATIONALE

Aortic aneurysm (AA) is a serious condition that largely increases the risk of aortic dissection and sudden death. Exploring the global burden of disease and changes in risk factors for AA is essential for public health policy development.

OBJECTIVE

To project the death burden from AA and its attributable risk factors in the following decade based on the epidemiological data over the past 30 years.

METHODS AND RESULTS

We analysed the death burden of AA and trends of four risk factors from 1990-2019 using the updated 2019 Global Burden of Disease study database by Joinpoint regression analysis. Furthermore, we project the AA-related death burden for the next decade using the Bayesian age-period-cohort model. This study discovered that the global burden of death attributable to AA began to increase after decreasing for two decades. This upward trend will continue in the subsequent decade (average annual percent change: 0.318%, 95% CI: 0.288 to 0.348). Meanwhile, the disease burdens in all economic regions except high-middle socio-demographic index (SDI) regions will continuously increase in the next decade, with the fastest acceleration in the low-middle SDI region (average annual percent change: 1.183%, 95% CI: 1.166 to 1.200). Notably, high systolic blood pressure will surpass the contribution of smoking to become the most important risk factor for mortality due to AA.

CONCLUSION

This study discovered a rebounding trend in the aortic aneurysm-related death burden globally. High systolic blood pressure will be the top risk factor attributed to death from AA. Therefore, it should be considered as the first-degree risk factor in the guidance of AA management and criteria for population-based screening programs.Key messagesThe death burden of aortic aneurysms is beginning to rebound globally, and the trend will continue for the next decade.High systolic blood pressure will replace smoking as the most important risk factor associated with aortic aneurysm death.

Editor's Choice - Systematic Review and Meta-Analysis of Normal Infrarenal Aortic Diameter in the General Worldwide Population and Changes in Recent Decades

OBJECTIVE

To analyse the characteristics of normal infrarenal aortic diameter (AD) in the general worldwide population, to examine changes over time, and to investigate geographical differences.

DATA SOURCES

PubMed, Cochrane Library, and Web of Science.

REVIEW METHODS

This was a systematic review and meta-analysis of studies published up to October 2020 describing infrarenal AD measured by ultrasound in the general adult population. The study was conducted in accordance with the PRISMA statement and placed no restrictions on geographical location or year of publication. Studies of individuals pre-selected for certain diseases or risk factors and opportunistic screening were excluded. A random effects model was used to estimate pooled mean AD, and meta-regression analysis was used to study the effects of determinants of AD.

RESULTS

Thirty-two studies were included, reporting data for 941 144 individuals (98% were men). The pooled mean AD was 19.4 mm (95% confidence interval [CI] 18.8 - 20.1), being 20.1 mm (95% CI 19.4 - 20.8) in men and 17.8 mm (95% CI 16.5 - 19.1) in women (p < .001). Outer edge to outer edge (OTO) caliper placement method (p = .015) and body surface area (BSA; p = .010) were significantly associated with larger AD. In men, the largest mean AD was observed in Oceania (p < .001) and the smallest in Asia (p < .020). As none of the studies collected data between 2002 and 2007, the studies were divided into two periods: 2001 and before, and 2008 and after. All recent studies were European, with the diameters being significantly smaller (p = .003) in the latter period (18.3 mm [95% CI 17.5 - 19.1] vs. 20.7 mm [95% CI 19.1 - 22.3]). In the meta-regression models, the reduction in AD over time remained significant after adjustment for potential effect modifiers such as sex, age, geographical area, body size, cardiovascular risk factors, and ultrasound method.

CONCLUSION

Mean infrarenal AD in older European adults has decreased significantly in recent decades. Male sex, BSA, and OTO ultrasound measurement method are associated with larger AD, and geographical differences were observed in men.

Guidelines on the management of abdominal aortic aneurysms: updates from the Italian Society of Vascular and Endovascular Surgery (SICVE)

The objective of these Guidelines was to revise and update the previous 2016 Italian Guidelines on Abdominal Aortic Aneurysm Disease, in accordance with the National Guidelines System (SNLG), to guide every practitioner toward the most correct management pathway for this pathology. The methodology applied in this update was the GRADE-SIGN version methodology, following the instructions of the AGREE quality of reporting checklist as well. The first methodological step was the formulation of clinical questions structured according to the PICO (Population, Intervention, Comparison, Outcome) model according to which the Recommendations were issued. Then, systematic reviews of the Literature were carried out for each PICO question or for homogeneous groups of questions, followed by the selection of the articles and the assessment of the methodological quality for each of them using qualitative checklists. Finally, a Considered Judgment form was filled in for each clinical question, in which the features of the evidence as a whole are assessed to establish the transition from the level of evidence to the direction and strength of the recommendations. These guidelines outline the correct management of patients with abdominal aortic aneurysm in terms of screening and surveillance. Medical management and indication for surgery are discussed, as well as preoperative assessment regarding patients' background and surgical risk evaluation. Once the indication for surgery has been established, the options for traditional open and endovascular surgery are described and compared, focusing specifically on patients with ruptured abdominal aortic aneurysms as well. Finally, indications for early and late postoperative follow-up are explained. The most recent evidence in the Literature has been able to confirm and possibly modify the previous recommendations updating them, likewise to propose new recommendations on prospectively relevant topics.

Psychosocial consequences of screening-detected abdominal aortic aneurisms: a cross-sectional study

OBJECTIVE

In Sweden, an abdominal aortic aneurysm (AAA) screening programme was gradually implemented from 2009 to reduce the incidence of rupture and thereby mortality. AAA screening introduces a variety of unintended, but generally unavoidable, harms, e.g. stress and worry. Such psychosocial consequences have previously only been investigated with generic measures. Therefore, the aim of this study was to describe and compare the psychosocial consequences in men with a screening detected AAA to men with a normal screening result after they participated in the Swedish national AAA-screening programme using a validated psychometric instrument.

MATERIAL AND METHODS

This study was a cross-sectional survey. Data were originally collected to validate the COS-AAA and has previously been published in details. The Consequences of Screening in Abdominal Aortic Aneurysm (COS-AAA) questionnaire was sent to 250 men with a screening detected AAA and 500 with a normal screening result who were randomly selected from a Swedish population-based screening register.

RESULTS

In total, 158 (63%) men with a screening detected AAA and 275 (55%) men with a normal screening result completed the COS-AAA. We found that men with a screening detected AAA reported negative psychosocial consequences to a greater extent in 10 of 13 COS-AAA Part 1 scales, all statistically significant except three (behaviour, sleep and negative experiences from examination). For COS-AAA Part 2, there was a statistically significant difference between groups in four of five scales.

CONCLUSIONS

Men diagnosed with a screening detected AAA, reported more negative psychosocial consequences compared to men with a normal result. Screening for abdominal aorta aneurism (AAA) introduces intended benefits and unintended harms. Adequate measures are necessary to determine the balance between them.Key points:This study applied a condition-specific questionnaire with high content validity and adequate psychometric properties to measure psychosocial consequences in men participating in AAA screening.We found that men with a screening detected AAA reported more negative psychosocial consequences than men with a normal aorta size.The risk of negative psychosocial consequences is important to include in the decision making on whether to participate in screening or not.

MFAP4 Deficiency Attenuates Angiotensin II-Induced Abdominal Aortic Aneurysm Formation Through Regulation of Macrophage Infiltration and Activity

Objective: Abdominal aortic aneurysm (AAA) is a common age-related vascular disease characterized by progressive weakening and dilatation of the aortic wall. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix (ECM) protein involved in the induction of vascular remodeling. This study aimed to investigate if MFAP4 facilitates the development of AAA and characterize the underlying MFAP4-mediated mechanisms.

Approach and Results: Double apolipoprotein E- and Mfap4-deficient (ApoE^−/−Mfap4^−/−) and control apolipoprotein E-deficient (ApoE^−/−) mice were infused subcutaneously with angiotensin II (Ang II) for 28 days. Mfap4 expression was localized within the adventitial and medial layers and was upregulated after Ang II treatment. While Ang II-induced blood pressure increase was independent of Mfap4 genotype, ApoE^−/−Mfap4^−/− mice exhibited significantly lower AAA incidence and reduced maximal aortic diameter compared to ApoE^−/− littermates. The ApoE^−/−Mfap4^−/− AAAs were further characterized by reduced macrophage infiltration, matrix metalloproteinase (MMP)-2 and MMP-9 activity, proliferative activity, collagen content, and elastic membrane disruption. MFAP4 deficiency also attenuated activation of integrin- and TGF-β-related signaling within the adventitial layer of AAA tissues. Finally, MFAP4 stimulation promoted human monocyte migration and significantly upregulated MMP-9 activity in macrophage-like THP-1 cells.

Conclusion: This study demonstrates that MFAP4 induces macrophage-rich inflammation, MMP activity, and maladaptive remodeling of the ECM within the vessel wall, leading to an acceleration of AAA development and progression. Collectively, our findings suggest that MFAP4 is an essential aggravator of AAA pathology that acts through regulation of monocyte influx and MMP production.

Circular RNA Expression: Its Potential Regulation and Function in Abdominal Aortic Aneurysms

Abdominal aortic aneurysms (AAAs) have posed a great threat to human life, and the necessity of its monitoring and treatment is decided by symptomatology and/or the aneurysm size. Accumulating evidence suggests that circular RNAs (circRNAs) contribute a part to the pathogenesis of AAAs. circRNAs are novel single-stranded RNAs with a closed loop structure and high stability, having become the candidate biomarkers for numerous kinds of human disorders. Besides, circRNAs act as molecular "sponge" in organisms, capable of regulating the transcription level. Here, we characterize that the molecular mechanisms underlying the role of circRNAs in AAA development were further elucidated. In the present work, studies on the biosynthesis, bibliometrics, and mechanisms of action of circRNAs were aims comprehensively reviewed, the role of circRNAs in the AAA pathogenic mechanism was illustrated, and their potential in diagnosing AAAs was examined. Moreover, the current evidence about the effects of circRNAs on AAA development through modulating endothelial cells (ECs), macrophages, and vascular smooth muscle cells (VSMCs) was summarized. Through thorough investigation, the molecular mechanisms underlying the role of circRNAs in AAA development were further elucidated. The results demonstrated that circRNAs had the application potential in the diagnosis and prevention of AAAs in clinical practice. The study of circRNA regulatory pathways would be of great assistance to the etiologic research of AAAs.

Screening Older Adult Men for Abdominal Aortic Aneurysm: A Scoping Review

Abdominal aortic aneurysm (AAA) is a potentially fatal condition predominantly affecting older adult men (60 years or over). Based on evidence, preventative health-care guidelines recommend screening older males for AAA using ultrasound. In attempts to reduce AAA mortality among men, screening has been utilized for early detection in some Western countries including the UK and Sweden. The current scoping review includes 19 empirical studies focusing on AAA screening in men. The findings from these studies highlight benefits and potential harms of male AAA screening. The benefits of AAA screening for men include decreased incidence of AAA rupture, decreased AAA mortality, increased effectiveness of elective AAA repair surgery, and cost-effectiveness. The potential harms of AAA screening included lack of AAA mortality reduction, negative impacts on quality of life, and inconsistent screening eligibility criteria being applied by primary care practitioners. The current scoping review findings are discussed to suggest changes to AAA screening guidelines and improve policy and practice.

[Opportunistic screening for abdominal aortic aneurysm during echocardiography in patients with coronary artery disease: Utility or futility?]

Abdominal aortic aneurysm is a chronic degenerative disease that is usually silent until rupture occurs and this complication is still associated in contemporary era with a high rate of mortality. Screening programmes for abdominal aortic aneurysm have been shown to be effective in reducing global mortality in the screened population but these programmes are poorly implemented in the Western countries. As coronary artery disease and abdominal aorta aneurysmal disease share many risk factors, the cardiologist is centrally positioned in the screening strategy, not only to identify patients with higher risk of developing abdominal aortic aneurysm, but also to perform an opportunistic screening during echocardiography. This paper summarises evidence about the feasibility, indications, modalities, benefits and risks related to the opportunistic screening for abdominal aortic aneurysm during echocardiography with a particular emphasis on the population of patients with coronary artery disease.

Screening cardiovascular patients for aortic aneurysms (SCAN) - high prevalence of abdominal aortic aneurysms in coronary heart disease patients requiring intervention

Background: Since the prevalence of abdominal aortic aneurysms (AAA) in Europe has declined to about 2.5%, general screening programs of elderly men are being called into question. On the other hand, other vascular diseases (e.g. coronary heart disease, CHD) are associated with a higher prevalence of AAA. This might have an impact on future targeted AAA screening programs. This study aimed to reevaluate the current prevalence of AAA in male patients with CHD, in order to assess whether CHD patients should be offered a targeted AAA ultrasound screening program. Patients and methods: The SCAN (Screening Cardiovascular Patients for Aortic Aneurysms) study prospectively evaluated the AAA prevalence in 1000 consecutive male CHD patients (70.1 ± 11.2 years) requiring any coronary intervention at an university hospital. All patients received transverse and longitudinal ultrasound scans of the abdominal aorta. Aortic diameter was assessed using the outer-to-outer measurement-technique. Primary endpoint was the prevalence of AAA. Secondary outcomes included stratification in 1-, 2-, or 3-vessel CHD. Results: AAA was detected in 85 patients (median diameter 38 mm, range 30-80 mm), corresponding to an overall prevalence of 8.5%. AAA prevalence was significantly associated with CHD severity: 5.6% in 1-vessel, 7.1% in 2-vessel, and 10.8% in 3-vessel CHD (P = 0.037). The multivariable analysis showed, that age per 10 years increase (OR 1.5, 95% CI 1.2-1.9, P = 0.001) and hyperlipidemia (OR 2.2, 95% CI 1.3-3.8, P = 0.003) were significantly associated with an AAA. The likelihood to be diagnosed with an AAA was significantly lower in non-smokers (OR 0.24, 95% CI, P < 0.001). Conclusions: This study confirms that CHD requiring any type of coronary intervention is strongly associated with AAA in male patients. AAA prevalence increases with CHD severity. Since the AAA prevalence is still significantly higher than in the general population, targeted ultrasound screening should be considered for all CHD patients.

Aortic aneurysm screening using duplex ultrasound: Choosing wisely who to examine

The noninvasive vascular laboratory plays a critical role in screening patients at risk for development of abdominal aortic aneurysm (AAA). One-time duplex ultrasound screening reduces aneurysm-related mortality due to rupture and is cost-effective. Population screening based on AAA risk factors is recommended, as it allows for proactive, elective repair of aneurysms at risk for rupture, and surveillance of smaller aneurysms for enlargement. Utilization of societal screening guidelines, such as those published by the Society for Vascular Surgery, can be employed by vascular laboratories to justify individual patient screening, aid primary care physicians to refer patients for testing, and encourage integrated medical health care systems to build prompts in patient electronic health records to ensure compliance with a AAA screening program. Risk factors for developing AAA, that is, age older than 65 years, male sex, family history, and a smoking history of >100 cigarettes, should be used to recommend patient screening, including for women and other elderly (older than 75 years) patients who fall outside of professional societal guidelines.

Editor's Choice - Assessment of Correlation Between Mean Size of Infrarenal Abdominal Aortic Aneurysm at Time of Intact Repair Against Repair and Rupture Rate in Nine Countries

OBJECTIVE

This study aimed to analyse the mean abdominal aortic aneurysm (AAA) diameter for repair in nine countries, and to determine variation in mean AAA diameter for elective AAA repair and its relationship to rupture AAA repair rates and aneurysm related mortality in corresponding populations.

METHODS

Data on intact (iAAA) and ruptured infrarenal AAA (rAAA) repair for the years 2010-2012 were collected from Denmark, England, Finland, Germany, Hungary, New Zealand, Norway, Sweden, and the USA. The rate of iAAA repair and rAAA per 100 000 inhabitants above 59 years old, mean AAA diameter for iAAA repair and rAAA repair, and the national rates of rAAA were assessed. National cause of death statistics were used to estimate aneurysm related mortality. Direct standardisation methods were applied to the national mortality data. Logistic regression and analysis of variance model adjustments were made for age groups, sex, and year.

RESULTS

There was a variation in the mean diameter of iAAA repair (n = 34 566; range Germany = 57 mm, Denmark = 68 mm). The standardised iAAA repair rate per 100000 inhabitants varied from 10.4 (Hungary) to 66.5 (Norway), p<.01, and the standardised rAAA repair rate per 100 000 from 5.8 (USA) to 16.9 (England), p<.01. Overall, there was no significant correlation between mean diameter of iAAA repair and standardised iAAA rate (r² = 0.04, p = .3). There was no significant correlation between rAAA repair rate (n = 12 628) with mean diameter of iAAA repair (r² = 0.2, p = .1).

CONCLUSION

Despite recommendations from learned society guidelines, data indicate variations in mean diameter for AAA repair. There was no significant correlation between mean diameter of AAA repair and rates of iAAA repair and rAAA repair. These analyses are subject to differences in disease prevalence, uncertainties in rupture rates, validations of vascular registries, causes of death and registrations.

Out-of-hospital cardiac arrest: Causes according to autopsy and electrocardiography - Analysis of 781 patients with neither hospital care nor prescribed medication during the preceding two years

BACKGROUND

There is a knowledge gap regarding aetiology of and potential for predicting out-of-hospital cardiac arrest (OHCA) among individuals who are healthy before the event.

AIM

To describe causes of OHCA and the potential for predicting OHCA in apparently healthy patients.

METHODS

Patients were recruited from the Swedish Register of Cardiopulmonary Resuscitation from November 2007 to January 2011. Inclusion criteria were: OHCA with attempted CPR but neither dispensed prescription medication nor hospital care two years before the event The register includes the majority of patients suffering OHCA in Sweden where cardiopulmonary resuscitation (CPR) was attempted. Medication status was defined by linkage to the Swedish Prescribed Drug Register. Cause of death was assessed based on autopsy and the Swedish Cause of Death Register. Prediction of OHCA was attempted based on available electrocardiograms (ECG) before the OHCA event.

RESULTS

Altogether 781 individuals (16% women) fulfilled the inclusion criteria. Survival to 30 days was 16%. Autopsy rate was 72%. Based on autopsy, 70% had a cardiovascular aetiology and 59% a cardiac aetiology. An ECG recording before the event was found in 23% of cases. The ECG was abnormal in 22% of them.

CONCLUSION

Among OHCA victims who appeared to be healthy prior to the event, the cause was cardiovascular in the great majority according to autopsy findings. A minority had a preceding abnormal ECG that could have been helpful in avoiding the event.

Circular RNA expression profile and its potential regulative role in human abdominal aortic aneurysm

Background

This study aimed to identify the differentially expressed circular RNAs (circRNAs) between human abdominal aortic aneurysm (AAA) and the control group.

Methods

High-throughput sequencing was applied to determine the circRNA expression profiles of 4 paired aortic samples. Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was carried out to testify 6 randomly selected dysregulated circRNAs. Kyoto Encyclopedia of Genes and Genomes and Gene ontology (GO) analysis were conducted for functional annotation of the parental genes. Additionally, interaction networks between circRNA and 5 putative microRNA (miRNA) partners were constructed.

Results

Finally, 411 differentially expressed circRNAs were discovered, including 266 downregulated and 145 upregulated circRNAs. Compared with the control group, the expression level of hsa (Homo sapiens) _circ_0005360 (LDLR) and hsa_circ_0002168 (TMEM189) were proved significantly lower in the AAA group by qRT-PCR. Regarding upregulated circRNAs, the most enriched GO molecular function, biological process and cellular component terms were poly(A) RNA binding, negative regulation of transcription from RNA polymerase II promoter and nucleoplasm, respectively. Moreover, circRNA/miRNA interaction networks showed that hsa_circ_0005360/miR-181b and hsa_circ_0002168/miR-15a axis might have a regulative role in human AAA.

Conclusions

This study revealed new circRNAs potentially related to the pathogenesis of AAA. Further experimental studies are warranted to clarify the potential molecular mechanisms.

Editor's Choice - Endovascular vs. Open Repair for Abdominal Aortic Aneurysm: Systematic Review and Meta-analysis of Updated Peri-operative and Long Term Data of Randomised Controlled Trials

OBJECTIVE

The objective was to investigate whether endovascular aneurysm repair (EVAR) has better peri-operative and late clinical outcomes than open repair for non-ruptured abdominal aortic aneurysm.

METHODS

Electronic bibliographic sources (MEDLINE, EMBASE, and CENTRAL) were searched up to July 2019 using a combination of thesaurus and free text terms to identify randomised controlled trials (RCTs) comparing the outcomes of EVAR and open repair. The systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) or risk difference (RD) and 95% confidence interval (CI). A time to event data meta-analysis was performed using the inverse variance method and the results were reported as summary hazard ratio (HR) and 95% CI.

RESULTS

Seven RCTs reporting a total of 2 983 patients were included in quantitative synthesis. Three of the trials reported long term follow up that extended to 15.8 years, 14.2 years, and 12.5 years. Meta-analysis found significantly lower odds of 30 day (OR, 0.36; 95% CI 0.20-0.66) and in hospital mortality with EVAR (RD -0.03; 95% CI -0.04 to -0.02). Meta-analysis of the three trials reporting long term follow up found no significant difference in all cause mortality at any time between EVAR and open repair (HR 1.02; 95% CI 0.93-1.13; p = .62). The hazard of all cause (HR 0.62; 95% CI 0.42-0.91) and aneurysm related death within six months (HR 0.42; 95% CI 0.24-0.75) was significantly lower in patients who underwent EVAR, but with further follow up, the pooled hazard estimate moved in favour of open surgery; in the long term (>8 years) the hazard of aneurysm related mortality was significantly higher after EVAR (HR 5.12; 95% CI 1.59-16.44). The risk of secondary intervention (HR 2.13; 95% CI 1.69-2.68), aneurysm rupture (OR, 5.08; 95% CI 1.11-23.31), and death due to rupture (OR, 3.57; 95% CI 1.87-6.80) was significantly higher after EVAR, but the risk of death due to cancer was not significantly different between EVAR and open repair (OR, 1.03; 95% CI 0.84-1.25).

CONCLUSION

Compared with open surgery, EVAR results in a better outcome during the first six months but carries an increased risk of aneurysm related mortality after eight years.

Screening for Abdominal Aortic Aneurysm: US Preventive Services Task Force Recommendation Statement

IMPORTANCE

An abdominal aortic aneurysm (AAA) is typically defined as aortic enlargement with a diameter of 3.0 cm or larger. The prevalence of AAA has declined over the past 2 decades among screened men 65 years or older in various European countries. The current prevalence of AAA in the United States is unclear because of the low uptake of screening. Most AAAs are asymptomatic until they rupture. Although the risk for rupture varies greatly by aneurysm size, the associated risk for death with rupture is as high as 81%.

OBJECTIVE

To update its 2014 recommendation, the USPSTF commissioned a review of the evidence on the effectiveness of 1-time and repeated screening for AAA, the associated harms of screening, and the benefits and harms of available treatments for small AAAs (3.0-5.4 cm in diameter) identified through screening.

POPULATION

This recommendation applies to asymptomatic adults 50 years or older. However, the randomized trial evidence focuses almost entirely on men aged 65 to 75 years.

EVIDENCE ASSESSMENT

Based on a review of the evidence, the USPSTF concludes with moderate certainty that screening for AAA in men aged 65 to 75 years who have ever smoked is of moderate net benefit. The USPSTF concludes with moderate certainty that screening for AAA in men aged 65 to 75 years who have never smoked is of small net benefit. The USPSTF concludes that the evidence is insufficient to determine the net benefit of screening for AAA in women aged 65 to 75 years who have ever smoked or have a family history of AAA. The USPSTF concludes with moderate certainty that the harms of screening for AAA in women aged 65 to 75 years who have never smoked and have no family history of AAA outweigh the benefits.

RECOMMENDATIONS

The USPSTF recommends 1-time screening for AAA with ultrasonography in men aged 65 to 75 years who have ever smoked. (B recommendation) The USPSTF recommends that clinicians selectively offer screening for AAA with ultrasonography in men aged 65 to 75 years who have never smoked rather than routinely screening all men in this group. (C recommendation) The USPSTF recommends against routine screening for AAA with ultrasonography in women who have never smoked and have no family history of AAA. (D recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for AAA with ultrasonography in women aged 65 to 75 years who have ever smoked or have a family history of AAA. (I statement).

Retrospective review of abdominal aortic aneurysm deaths in New Zealand: what proportion of deaths is potentially preventable by a screening programme in the contemporary setting?

OBJECTIVES

To describe the proportions of people dying from abdominal aortic aneurysm (AAA) who might have benefited from a formal screening programme for AAA.

DESIGN

Retrospective cross-sectional review of deaths.

SETTING AND STUDY POPULATIONS

All AAA deaths registered in New Zealand from 2010 to 2014 in the absence of a national AAA screening programme.

MAIN OUTCOME MEASURES

Known history of AAA prior to the acute event leading to AAA death, prognosis limiting comorbidities, history of prior abdominal imaging and a validated multimorbidity measure (M3-index scores).

RESULTS

1094 AAA deaths were registered in the 5 years between 2010 and 2014 in New Zealand. Prior to the acute AAA event resulting in death, 31.3% of the cohort had a known AAA diagnosis, and 10.9% had a previous AAA procedure. On average, the AAA diagnosis was known 3.7 years prior to death. At least 77% of the people dying from AAA also had one or more other prognosis limiting diagnosis. The hazard of 1-year mortality associated with the non-AAA related comorbidities for the AAA cohort aged 65 or above were 1.5-2.6 times higher than to the age matched general population based on M3-index scores. In 2014, overall AAA deaths accounted for only 0.7% of total deaths, and 1.0% of deaths among men aged 65 or above in New Zealand. At most, 20% of people dying from AAA in New Zealand between 2010 and 2014 might have had the potential to derive full benefit from a screening programme. About 51% of cases would have derived no or very limited benefit from a screening programme.

CONCLUSION

Falling AAA mortality, and high prevalence of competing comorbidities and/or prior AAA diagnosis and procedure raises the question about the likely value of a national AAA screening programme in a country such as New Zealand.

Health gains, costs and cost-effectiveness of a population-based screening programme for abdominal aortic aneurysms

BACKGROUND

Abdominal aortic aneurysm (AAA) rupture carries a high fatality rate. AAAs can be detected before rupture by abdominal ultrasound imaging, allowing elective repair. Population-based screening for AAA in older men reduces AAA-related mortality by about 40 per cent. The UK began an AAA screening programme offering one-off scans to men aged 65 years in 2009. Sweden has a similar programme. Currently, there is no AAA screening programme in New Zealand. This cost-utility analysis aimed to assess the cost-effectiveness of a UK-style screening programme in the New Zealand setting.

METHODS

The analysis compared a formal AAA screening programme (one-off abdominal ultrasound imaging for about 20 000 men aged 65 years in 2011) with no systematic screening. A Markov macrosimulation model was adapted to estimate the health gains (in quality-adjusted life-years, QALYs), health system costs and cost-effectiveness in New Zealand. A health system perspective and lifetime horizon was adopted.

RESULTS

With New Zealand-specific inputs, the adapted model produced an estimate of about NZ $15 300 (€7746) per QALY gained, with a 95 per cent uncertainty interval (UI) of NZ $8700 to 31 000 (€4405 to 15 694) per QALY gained. Health gains were estimated at 117 (95 per cent UI 53 to 212) QALYs. Health system costs were NZ $1·68 million (€850 535), with a 95 per cent UI of NZ $820 200 to 3·24 million (€415 243 to €1·65 million).

CONCLUSION

Using New Zealand's gross domestic product per capita (about NZ $45 000 or €22 100) as a cost-effectiveness threshold, a UK-style AAA screening programme would be cost-effective in New Zealand.

Screening based on risk factors for abdominal aortic aneurysm in the cardiology clinic

BACKGROUND

The risk factors for abdominal aortic aneurysm (AAA) are present in many of the patients that attend our cardiology service. The aim of this study was the evaluation of the prospects of examining the abdominal aorta during our consultations and the relationship of AAA with risk factors and ischemic cardiopathy.

METHODS

A descriptive transversal observational study was designed including 274 male patients aged ≥60 years, attended consecutively in the cardiology service, in which we studied the abdominal aorta and adjusted a logistic regression model to determine the risk factors associated with AAA.

RESULTS

We were able to visualize and measure the abdominal aorta in 95.4% of cases in a fast and reliable way. The prevalence of AAA was 8.76%. 75% of patients with AAA presented ischemic heart disease. Patients with AAA were characterized by the presence of ischemic cardiopathy (Odds Ratio (OR): 4.27, 95% Confidence Interval (CI): 1.37-13.31, p = 0.012), dyslipidemia (OR: 4.99, 95% CI: 1, 07-23.31; p = 0.041), arterial hypertension (OR: 4.14, 95% CI: 1.07-15.98, p = 0.039), and a longer history of smoking (OR: 1.03; 95% CI: 1002-1.054; p = 0.037).

CONCLUSIONS

The evaluation of the abdominal aorta during cardiology consultations is feasible with the standard resources. Patients treated in the cardiology service present a high prevalence of AAA. We have adjusted and validated a clinical prediction model based on risk factors that allows the identification, in the cardiology consult, of patients with the highest risk of suffering from AAA.

Safety of Men With Small and Medium Abdominal Aortic Aneurysms Under Surveillance in the NAAASP

BACKGROUND

Population screening for abdominal aortic aneurysm (AAA) has commenced in several countries, and has been shown to reduce AAA-related mortality by up to 50%. Most men who screen positive have an AAA <5.5 cm in diameter, the referral threshold for treatment, and are entered into an ultrasound surveillance program. This study aimed to determine the risk of ruptured AAA (rAAA) in men under surveillance.

METHODS

Men in the National Health Service AAA Screening Programme who initially had a small (3-4.4 cm) or medium (4.5-5.4 cm) AAA were followed up. The screening program's database collected data on ultrasound AAA diameter measurements, dates of referral, and loss to follow-up. Local screening programs recorded adverse outcomes, including rAAA and death. Rupture and mortality rates were calculated by initial and final known AAA diameter.

RESULTS

A total of 18 652 men were included (50 103 person-years of surveillance). Thirty-one men had rAAA during surveillance, of whom 29 died. Some 952 men died of other causes during surveillance, mainly cardiovascular complications (26.3%) and cancer (31.2%). The overall mortality rate was 1.96% per annum, similar for men with small and medium AAAs. The rAAA risk was 0.03% per annum (95% CI, 0.02%-0.05%) for men with small AAAs and 0.28% (0.17%-0.44%) for medium AAAs. The rAAA risk for men with AAAs just below the referral threshold (5.0-5.4 cm) was 0.40% (0.22%-0.73%).

CONCLUSIONS

The risk of rAAA under surveillance is <0.5% per annum, even just below the present referral threshold of 5.5 cm, and only 0.4% of men under surveillance are estimated to rupture before referral. It can be concluded that men with small and medium screen-detected AAAs are safe provided they are enrolled in an intensive surveillance program, and that there is no evidence that the current referral threshold of 5.5 cm should be changed.

Risk Factors for Abdominal Aortic Aneurysm in Population-Based Studies: A Systematic Review and Meta-Analysis

Abdominal aortic aneurysm (AAA) represents an important public health problem with a prevalence between 1.3% and 12.5%. Several population-based randomized trials have evaluated ultrasound screening for AAA providing evidence of a reduction in aneurysm-related mortality in the screened population. The aim of our study was to perform a systematic review and meta-analysis of the risk factors for AAA. We conducted a systematic review of observational studies and we performed a meta-analysis that evaluated the following risk factors: gender, smoking habits, hypertension, coronary artery disease and family history of AAA. Respect to a previous a meta-analysis we added the funnel plot to examine the effect sizes estimated from individual studies as measure of their precision; sensitivity analysis to check the stability of study findings and estimate how the overall effect size would be modified by removal of one study; cumulative analysis to evaluate the trend between studies in relation to publication year. Abdominal aortic aneurysm prevalence is higher in smokers and in males. On the other hand, while diabetes is a risk factor for many cardiovascular diseases, it is not a risk factor for AAA. In addition, it is important to underline that all countries, where AAA screening was set up, had high income level and the majority belong to Western Europe (United Kingdom, Sweden, Italy, Poland, Spain and Belgium). Abdominal aortic aneurysm screening is fundamental for public health. It could avoid deaths, ruptures, and emergency surgical interventions if abdominal aortic aneurysm was diagnosed early in the population target for screening.

Abdominal aortic aneurysms

An abdominal aortic aneurysm (AAA) is a localized dilatation of the infrarenal aorta. AAA is a multifactorial disease, and genetic and environmental factors play a part; smoking, male sex and a positive family history are the most important risk factors, and AAA is most common in men >65 years of age. AAA results from changes in the aortic wall structure, including thinning of the media and adventitia due to the loss of vascular smooth muscle cells and degradation of the extracellular matrix. If the mechanical stress of the blood pressure acting on the wall exceeds the wall strength, the AAA ruptures, causing life-threatening intra-abdominal haemorrhage - the mortality for patients with ruptured AAA is 65-85%. Although AAAs of any size can rupture, the risk of rupture increases with diameter. Intact AAAs are typically asymptomatic, and in settings where screening programmes with ultrasonography are not implemented, most cases are diagnosed incidentally. Modern functional imaging techniques (PET, CT and MRI) may help to assess rupture risk. Elective repair of AAA with open surgery or endovascular aortic repair (EVAR) should be considered to prevent AAA rupture, although the morbidity and mortality associated with both techniques remain non-negligible.