[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.

[Summary of the S3 guideline on abdominal aortic aneurysm from an anesthesiological perspective]

The current article is a summary of the 2018 revised S3 guideline on screening, diagnosis, therapy, and follow-up of the abdominal aortic aneurysm (AAA) from an anesthesiological point of view. It is the only interdisciplinary guideline that describes in particular the perioperative anesthesiological and intensive care management.

Prevalence of abdominal aortic aneurysm and associated lower extremity artery aneurysm in men hospitalized for suspected or known cardiopulmonary disease

BACKGROUND

AAA is a disease affecting predominantly male patients ≥65 years and its dreaded complications such as rupture led to population-based screening programs as preventive measure. Nonetheless, the supposed prevalence may have been overestimated, so that targeted screening of high risk populations may be more effective. This study was performed to evaluate the prevalence of abdominal aortic aneurysm (AAA) of an inpatient high-risk cohort and to estimate the co-prevalence of lower extremity arterial aneurysms.

METHODS

Participants: 566 male inpatients, ≥ 65 years of age, hospitalized for suspected or known cardiopulmonary disease. Primary and secondary outcome measures: Maximal infrarenal aortic diameters using abdominal ultrasound (leading edge to leading edge method). Upon detection of an AAA (diameter ≥ 30 mm), the lower extremity arteries were examined with regard to associated aneurysms.

RESULTS

In 40 of 566 patients (7.1%) AAAs were detectable. Fourteen patients (2.5%) had a first diagnosis of AAA, none of which was large (> 55 mm), the remaining 26 patients were either already diagnosed (14 patients, 2.5%) or previously repaired (12 patients, 2.1%). The three most common main diagnoses at discharge were acute coronary syndrome (43.3%), congestive heart failure (32.2%), and chronic obstructive pulmonary disease (12%). The cohort showed a distinct cardiovascular risk profile comprising arterial hypertension (82.9%), diabetes mellitus (44.4%), and a history of smoking (57.6%). In multivariate analysis, three-vessel coronary artery disease (Odds ratio (OR): 4.5, 95% confidence interval (CI): 2.3-8.9, p <  0.0001) and history of smoking (OR: 3.7, CI: 1.6-8.6, p <  0.01) were positively associated with AAA, while diabetes mellitus (OR: 0.5, CI: 0.2-0.9, p = 0.0295) showed a negative association with AAA. Among the subjects with AAA, we found two large iliac and two large popliteal aneurysms.

CONCLUSION

Ultrasound screening in male inpatients, hospitalized for suspected or known cardiopulmonary disease, revealed a high AAA prevalence in comparison to the present epidemiological screening programs. There was a moderate proportion of newly-screen detected AAA and additional screening of the lower extremity arteries yielded some associated aneurysms with indication for possible intervention.

Electrocardiographic and echocardiographic features in patients with major arterial vascular disease assigned to surgical revascularization

Background: We aimed to depict the electrocardiographic and echocardiographic aspects in patients before elective major vascular surgery.Methods: We evaluated through standard 12 lead electrocardiography and transthoracic echocardiography 469 patients with asymptomatic large abdominal aortic aneurysm (AAA), 334 with critical carotid stenosis (CAS), and 238 with advanced peripheral artery disease (PAD) before surgical revascularization.Results: Patients with AAA were predominantly males (p < .001) with normal sinus rhythm (p = .026), were more affected by atrioventricular block (p = .033) and left anterior fascicular block (p < .001). They also presented larger aortic root size (p < .001) and septal hypertrophy (p = .036), in addition, atrial fibrillation was less frequent in the same group (p = .023). Patients with CAS were of older age (p < .001) with a substantial number of females (p < .001). They presented less left ventricular segmental kinetic disorders and fewer dilated ventricles (p = .004 and p < .001 respectively). Finally, those with PAD had reduced septal and posterior wall thickness (p < .01, p = .009 respectively), greater mitral and aortic annular calcification (p < .001), and were more affected by previous myocardial infarction (p < .001). The PR interval, left anterior fascicular block and aortic root size were independently associated with aneurysm, previous myocardial infarction with PAD, while smaller left ventricular end systolic volumes with carotid artery stenosis.Conclusions: Patients with AAA were mostly affected by cardiac conduction disorders, septal hypertrophy, aortic root dilation and less affected by atrial fibrillation. Patients with CAS were older with more normal sized ventricles, whereas, previous myocardial infarction was most common amongst patients with peripheral artery disease.

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.

Usefulness of Screening for Abdominal Aortic Aneurysm During Transthoracic Echocardiography in Women ≥50 Years of Age

Usefulness of screening for abdominal aortic aneurysm (AAA) during transthoracic echocardiography (TTE) in women is uncertain. The aim of the present study was to clarify the clinical usefulness of screening for AAA during TTE and to identify important TTE indices associated with AAA in women in a routine clinical setting. We prospectively studied 1,495 women (≥50 years) referred for TTE. AAA was defined as ≥30 mm in size. The additional screening time for AAA was <1 minute. The abdominal aorta was visualized in 95.1 % (1,422 of 1,495) using the same TTE probe. AAA was identified in 1.9% (27 of 1422). The aortic root size was larger in patients with AAA than those without (33.3 ± 3.2 vs 30.5 ± 3.4 mm, p < 0.001). The aortic root size had a correlation with abdominal aortic size (r = 0.22, p < 0.001). The aortic root size of ≥30.3 mm was predictive of AAA (area under the curve = 0.74, p < 0.001) and all patients with AAA had the aortic root size of ≥28.0 mm. Multiple logistic regression analysis revealed that the aortic root size (Odds ratio 1.17, p = 0.007) was a most independent TTE index of AAA. In conclusion, the visibility of the abdominal aorta using TTE probe was excellent. When the aortic root size is ≥28.0 mm during TTE in women ≥50 years of age, screening for AAA should be carried out.

Correcting for Body Surface Area Identifies the True Prevalence of Abdominal Aortic Aneurysm in Screened Women

OBJECTIVE

Recently, the prevalence of abdominal aortic aneurysm (AAA) using screening strategies based on elevated cardiovascular disease (CVD) risk was reported. AAA was defined as a diameter ≥30 mm, with prevalence of 6.1% and 1.8% in men and women respectively, consistent with the widely reported AAA predominant prevalence in males. Given the obvious differences in body size between sexes this study aimed to re-evaluate the expanded CVD risk based AAA screening dataset to determine the effect of body size on sex specific AAA prevalence.

METHODS

Absolute (26 and 30 mm) and relative (aortic size index [ASI] equals the maximum infrarenal aorta diameter (cm) divided by body surface area (m²), ASI ≥ 1.5) thresholds were used to assess targeted AAA screening groups (n = 4115) and compared with a self reported healthy elderly control group (n = 800).

RESULTS

Male AAA prevalence was the same using either the 30 mm or ASI ≥1.5 aneurysm definitions (5.7%). In females, AAA prevalence was significantly different between the 30 mm (2.4%) and ASI ≥ 1.5 (4.5%) or the 26 mm (4.4%) thresholds.

CONCLUSION

The results suggest the purported male predominance in AAA prevalence is primarily an artefact of body size differences. When aortic size is adjusted for body surface area there is only a modest sex difference in AAA prevalence. This observation has potential implications in the context of the ongoing discussion regarding AAA screening in women.

Predictors Associated With Increased Prevalence of Abdominal Aortic Aneurysm in Chinese Patients with Atherosclerotic Risk Factors

OBJECTIVE/BACKGROUND

Epidemiological screening studies have demonstrated that the prevalence of abdominal aortic aneurysm (AAA) of Asian origin appears to be low and so increases uncertainty about the cost effectiveness of screening for AAAs in Chinese people. Some studies have demonstrated a higher prevalence of AAA in patients with atherosclerotic risk factors. The purpose of the study was to determine the prevalence of AAA and to explore the high risk group of AAA in Chinese patients with atherosclerotic risk factors.

METHODS

From November 2014 to July 2015, a prospective observational study was conducted in Guangdong General Hospital. In total, 1582 consecutive patients with atherosclerotic risk factors and undergoing coronary angiography for suspected or known coronary artery disease were enrolled to be screened for AAA by abdominal aortic ultrasound. Because of inadequate ultrasound image quality, the analysis was based on the 1541 (97.4%) patients whose abdominal aortic ultrasound images were adequate.

RESULTS

The prevalence of AAA was 1.6% in the whole study population and 2.9% in male patients aged over 65 years. In multivariate analysis, age ≥ 65 years (p = .029), smoking (p = .037), hypertension (p = .026), and aortic root diameter > 30 mm (p = .003) were independent predictors of AAA. The prevalence of AAA was 0% (0/153) in patients without any independent predictor, 0.6% (3/502) in patients with one predictor, 1.0% (6/597) in patients with two predictors, 4.8% (12/249) in patients with three predictors, and up to 10% (4/40) in patients with four predictors (p<.001; p value for trend < .001).

CONCLUSION

Age ≥ 65 years, smoking, hypertension, and aortic root diameter > 30 mm emerged as independent predictors of AAA in Chinese patients. Stepwise increases in the prevalence of AAA were found to depend on the number of independent predictors. Ultrasound screening for AAA could be considered in these high risk patients, especially those with three or four predictors.

Comparison of three targeted approaches to screening for abdominal aortic aneurysm based on cardiovascular risk

BACKGROUND

Abdominal aortic aneurysm (AAA) continues to be a significant health burden yet few countries have implemented a comprehensive screening programme. Screening typically places emphasis on men aged over 65 years; however, there is concern that other at-risk groups may be underidentified. The present study examined three potential screening strategies based on cardiovascular risk.

METHODS

The prevalence of AAA was determined by abdominal ultrasound imaging in over 50-year-olds of either sex undergoing coronary angiography, vascular laboratory assessment of peripheral arterial disease, or community-based cardiovascular disease (CVD) event risk assessment. A fourth group, consisting of volunteers aged over 60 years who had no symptoms or signs of cardiovascular disease, was used as a comparator group.

RESULTS

A total AAA prevalence of 4·4 per cent was detected across all three strategies (137 of 3142 individuals), compared with 1·0 per cent in the CVD-free group. Male sex, age and smoking were all associated with greater AAA prevalence. Although AAA prevalence was lowest using the community-based strategy, those with an AAA detected were on average 7 years younger than those with AAAs detected with the other two strategies (P < 0·001).

CONCLUSION

Different strategies, based on CVD risk, resulted in AAA prevalence rates that were significantly greater than that in CVD-free individuals. This may provide opportunities for a targeted approach to community AAA screening in parts of the world where more sophisticated national screening programmes do not exist.

The impact of CT colonography on abdominal aortic aneurysm referrals in a tertiary hospital

INTRODUCTION

Computed tomography colonography (CTC) for the detection of colorectal disease is gaining popularity as an alternative to colonoscopy. This has been associated with an increase in incidental extra-colonic findings such as abdominal aortic aneurysms. However, due to the patient selection process of obtaining a CTC, it was hypothesised that this patient cohort might represent a high-risk group. The primary aim of this study was to determine the impact that CTC had on small aneurysm referrals. Owing to the potential selection bias, the secondary aim was to compare baseline characteristics referred by CTC to the cohort referred by other radiological modalities.

METHODS

Consecutive patients attending the small aneurysm clinic at a single tertiary centre were included. Baseline patient comorbidities were collected and recorded on a prospective database. The characteristics of patients who had a CTC-detected aneurysm were compared to patients referred by other radiological modalities.

RESULTS

There were 566 patients with small aneurysms included. Of these, 96 (17.0%) had their aneurysm detected from CTC and the remaining aneurysms were detected by other radiological modalities. These patients were on average 2 years older and were less likely to have a smoking history. There was no difference in other patient characteristics.

CONCLUSION

Computed tomography colonography contributed to the initial diagnosis of one in five patients with small aneurysms. Despite a potential selection bias for patients undergoing CTC, there were no major baseline differences between the CTC cohort and patients referred by other radiological modalities. Routine assessment of the aorta during a CTC may aid in aneurysm detection.

Prevalence of abdominal aortic aneurysm (AAA) in a population undergoing computed tomography colonography in Canterbury, New Zealand

OBJECTIVE/BACKGROUND

There is compelling level 1 evidence in support of screening men for abdominal aortic aneurysm (AAA) to reduce AAA mortality. However, New Zealand (NZ) lacks data on AAA prevalence, and national screening has not been implemented. The aim of this study was to determine the prevalence of AAA in a population undergoing a computed tomography colonography (CTC) for gastrointestinal symptoms.

METHODS

This was an observational study; all consecutive CTCs performed in three regions of the South Island of NZ over a 4 year period were reviewed. Data on abdominal and thoracic aorta diameters ≥30 mm, and iliac and femoral aneurysms ≥20 mm were recorded. Previous aortic surgical grafts or endovascular stents were also documented. Demographics, survival, and AAA related outcomes were collected and used for analysis.

RESULTS

Included were 4,893 scans on 4,644 patients (1,933 men [41.6%], 2,711 women [58.4%]) with a median age of 69.3 years (range 17.0-97.0 years). There were 309 scans on 289 patients (75.4% men) who had either an aneurysm or a previous aortic graft with a median age of 79.6 years (range 57.0-96.0 years). Of these, 223 had a native AAA ≥30 mm. The prevalence of AAA rose with age from 1.3% in men aged 55-64 years, to 9.1% in 65-74 year olds, 16.8% in 75-84 year olds, and 22.0% in ≥85 year olds. The corresponding figures in women were 0.4%, 2%, 3.9%, and 6.2%, respectively.

CONCLUSION

In this observational study, the prevalence of AAA was high and warrants further evaluation. The results acquired help to define a population that may benefit from a national AAA screening programme.