Distribution of aortic diameter in a screened male population.

Between September 1990 and August 1991, 2291 men aged 65 years were invited for ultrasonographic screening of the aorta in the Gloucestershire aneurysm screening programme; 1748 (76.3 per cent) attended. An aortic diameter less than or equal to 2.5 cm was found in 1547 (88.5 per cent); 174 (10.0 per cent) had diameters in the range 2.6-4.0 cm, and 26 (1.5 per cent) had diameters greater than 4.0 cm. The mean(s.d.) aortic diameter was 2.1(0.55) cm and 97.5 per cent of patients had a diameter less than or equal to 3.3 cm. Any man over the age of 65 years with an aortic diameter greater than 3.3 cm has an aortic aneurysm.     

Recommendations for screening intervals for small aortic aneurysms

BACKGROUND: The aim was to determine the optimum rescreening interval for small abdominal aortic aneurysms (AAAs). METHODS: Data from 12 years of population screening of 65-year-old men were analysed and 1121 small AAAs (less than 4.0 cm in initial diameter) were divided into groups: group 1 (2.6-2.9 cm; n = 625), group 2 (3.0-3.4 cm; n = 330) and group 3 (3.5-3.9 cm; n = 166). Expansion rate and the cumulative proportions to expand to over 5.5 cm, or require surgery, or rupture were calculated. RESULTS: Expansion rate was related to initial aortic diameter: 0.09 cm per year in group 1, 0.16 cm per year in group 2 and 0.32 cm per year in group 3 (P < 0.001). Aneurysms in 2.4 per cent of patients in group 1 exceeded a diameter of 5.5 cm or required surgery within 5 years; there were no ruptures. In group 2, no aorta exceeded 5.5 cm but at 3 years 2.1 per cent had reached 5.5 cm and 2.9 per cent had required surgery. The rupture rate at 3 years was zero. In group 3, the aneurysm diameter exceeded 5.5 cm in 1.2 per cent of patients, but no patient required surgery or experienced rupture within 1 year; at 2 years 10.5 per cent of aneurysms had exceeded 5.5 cm in diameter or required surgery and 1.4 per cent had ruptured. CONCLUSION: The appropriate rescreening interval can be determined by initial aortic diameter in screened 65-year-old men. AAAs of initial diameter 2.6-2.9 cm should be rescanned at 5 years, those of 3.0-3.4 cm at 3 years and those of 3.5-3.9 cm at 1 year.     

Prevalence of abdominal aortic aneurysm in patients with occlusive peripheral vascular disease

Over a 1-year period, 242 patients with peripheral vascular disease underwent abdominal ultrasonography to detect the presence of an abdominal aortic aneurysm. In 34 (14 per cent) an abdominal aortic aneurysm was found; half of these aneurysms were greater than 4 cm in diameter. In addition, 16 patients had ectatic aortas. Abdominal aortic aneurysms were more common in men than in women (17 versus 8 per cent). Patients with claudication were as likely to have an abdominal aortic aneurysm as those with rest pain or gangrene. The presence of aortoiliac occlusive disease increased the chance of an aneurysm being present (P less than 0.02). Patients with occlusive peripheral vascular disease are a high-risk group with regard to the development of an abdominal aortic aneurysm. Patients with proximal occlusive disease represent a subgroup at even higher risk.     

Abdominal aortic aneurysm rupture rates: A 7-year follow-up of the entire abdominal aortic aneurysm population detected by screening

Purpose: The goal of the current study was to identify the risk of rupture in the entire abdominal aortic aneurysm (AAA) population detected through screening and to review strategies for surgical intervention in light of this information. Methods: Two hundred eighteen AAAs were detected through ultrasound screening of a family practice population of 5394 men and women aged 65 to 80 years. Subjects with an AAA of less than 6.0 cm in diameter were followed prospectively with the use of ultrasound, according to our protocol, for 7 years. Patients were offered surgery if symptomatic, if the aneurysm expanded more than 1.0 cm per year, or if aortic diameter reached 6.0 cm. Results: The maximum potential rupture rate (actual rupture rate plus elective surgery rate) for small AAAs (3.0 to 4.4 cm) was 2.1% per year, which is less than most reported operative mortality rates. The equivalent rate for aneurysms of 4.5 to 5.9 cm was 10.2% per year. The actual rupture rate for aneurysms up to 5.9 cm using our criteria for surgery was 0.8% per year Conclusion: In centers with an operative mortality rate of greater than 2%, (1) surgical intervention is not indicated for asymptomatic AAAs of less than 4.5 cm in diameter, and (2) elective surgery should be considered only for patients with aneurysms between 4.5 and 6 cm in diameter that are expanding by more than 1 cm per year or for patients in whom symptoms develop. In centers with elective mortality rates of greater than 10% for abdominal aortic aneurysm (AAA) repair, the benefit to the patient of any surgical intervention for an asymptomatic AAA of less than 6.0 cm in diameter is questionable. (J Vasc Surg 1998;28:124-8.)     

Screening for abdominal aortic aneurysm in a geographically isolated area

BACKGROUND: Screening for abdominal aortic aneurysm has been shown to reduce aneurysm-related mortality, but the applicability of the results to the whole of the UK has been questioned. This study examined screening in a remote and rural area. METHODS: Over 3 years, men aged 65-74 years were offered screening in the community by ultrasonography, usually in general practitioner surgeries. Men with an aneurysm were rescanned at intervals or assessed for surgery. The screening and hospital costs of the programme were calculated. RESULTS: Some 9323 men were offered screening of whom 8355 (89.6 per cent) attended. Uptake was high in all areas. A total of 430 scans (5.1 per cent) were abnormal; 40 men had an aneurysm greater than 55 mm in diameter. Twenty further men had an aorta that enlarged to greater than 55 mm during follow-up. A total of 54 men had elective repair with one death (mortality rate 2 per cent). The cost of screening alone was 16 pound per invitation and the overall cost of the programme, including surgery, was 58 pound per invitation. CONCLUSION: Screening for abdominal aortic aneurysm can be carried out in a remote and rural area with high uptake, acceptable clinical results and at no greater cost than in more densely populated areas.     

Abdominal aortic aneurysm as an incidental finding in abdominal ultrasonography

The difference between the mortality rate from ruptured abdominal aortic aneurysm (overall mortality rate 85-95 per cent and operative mortality rate 23-63 per cent), and that for elective aneurysm repair (less than 5 per cent) is dramatic. Awareness of the existence of an abdominal aortic aneurysm is therefore essential. Of 1800 consecutive patients aged greater than or equal to 50 years referred for their first abdominal ultrasonography, 113 who had been referred specifically for suspected abdominal aortic aneurysm or vascular screening were excluded. The remaining 1687 patients (693 men and 994 women) form the study group. Apart from the symptom-directed examination, the entire abdomen of every patient was routinely studied by ultrasonography. The definition of an abdominal aortic aneurysm was a local dilatation of the aorta with an anteroposterior diameter greater than 30 mm or greater than 1.5 times the anteroposterior diameter of the proximal aorta. In 82 cases (4.9 per cent) an abdominal aortic aneurysm was disclosed; 61 were in men (8.8 per cent) and 21 were in women (2.1 per cent). The prevalence of abdominal aortic aneurysm as an incidental finding in men aged greater than or equal to 60 years was 11.4 per cent. In every patient aged greater than or equal to 50 years undergoing their first abdominal ultrasonography examination, the aorta should be screened for the presence of an aneurysm.     

Ultrasound screening of first-degree relatives of patients with an abdominal aortic aneurysm

The pedigrees were constructed of 43 patients (probands) who underwent resection of an abdominal aortic aneurysm. Seven probands (16.2%) had a first-degree relative (parent, sibling, child) known to have had an abdominal aortic aneurysm (multiplex family). To determine the prevalence of undiagnosed abdominal aortic aneurysm, ultrasound screening of first-degree relatives over age 40 years was undertaken. Of 202 eligible relatives, 103 (51.0%) were screened. An occult abdominal aortic aneurysm was defined as an infrarenal aortic diameter greater than 3.0 cm or an infrarenal/suprarenal aortic diameter ratio of greater than 1.5. An incipient abdominal aortic aneurysm was defined as a clear focal bulge of the infrarenal aorta, which was less than 3.0 cm in greatest diameter. Four of 103 relatives (3.9%) were found to have an occult abdominal aortic aneurysm (age/sex: 57M, 60M, 62F, 65M), and three (2.9%) were found with an incipient abdominal aortic aneurysm (age/sex: 56M, 60M, 67F). These smaller abdominal aortic aneurysms were in patients younger than the operated probands (average age men, 67 years; women, 69 years). Six of seven individuals were in families previously considered simplex, increasing the actual multiplex family frequency from 16.2% to 27.9%. All seven new abdominal aortic aneurysms were found in the 49 siblings age 55 years or older. There were no abdominal aortic aneurysms found in the 39 relatives under age 55 years, in 14 children ages 50 to 59 years or in one parent. Therefore of the siblings age 55 years or older, 5/20 men (25.0%) and 2/29 women (6.9%) were found to have a previously undiagnosed abdominal aortic aneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ultrasonographic screening of the abdominal aorta among siblings of patients with abdominal aortic aneurysms

To evaluate the prevalence of abdominal aortic dilatations among asymptomatic brothers and sisters of patients with abdominal aortic aneurysms (AAAs), an ultrasonographic screening study was performed. One hundred and two siblings of patients operated on for AAAs at two Swedish hospitals were invited to attend, and 87 of them (35 men and 52 women) from 32 different families, accepted the invitation. Their median age was 63 years (range 39-82 years). Aortic dilatation was diagnosed in ten of the brothers (29 per cent) and three of the sisters (6 per cent). In ten cases (eight men and two women) there was a localized dilatation caudal to the coeliac axis, and in three a general dilatation of the abdominal aorta with the diameter at the coeliac axis greater than 29 mm. None of the aortic dilatations had been known before this study was performed. The conclusion is that the prevalence of asymptomatic aortic dilatations among brothers of patients with AAAs seems to be high and that this group should be selected for further screening studies.     

The natural history of abdominal aortic aneurysms

This study examines the rate of expansion of abdominal aortic aneurysms and the risk of rupture in relation to their size. To assess these variables, we conducted a prospective study of 300 consecutive patients who presented over a 6-year interval with abdominal aortic aneurysms (AAA) that were initially managed nonoperatively. The mean age of the patients was 70.4 years, and 211 (70%) were men. The mean initial aneurysm diameter was 4.1 cm. Among the 208 patients who underwent more than one ultrasound or computed tomographic (CT) scan, the diameter of the aneurysm increased by a median of 0.3 cm per year. The 6-year cumulative incidence of rupture was 1% and 2% among patients with aneurysms less than 4.0 cm and 4.0 to 4.9 cm in diameter, respectively (p greater than 0.05). In comparison, the 6-year cumulative incidence of rupture was 20% among patients with aneurysms greater than 5.0 cm in diameter (p less than 0.004). We conclude that (1) abdominal aortic aneurysms expand at a median rate of 0.3 cm per year; and (2) the risk of rupture of abdominal aortic aneurysms less than 5.0 cm is substantially lower than the risk of rupture of aneurysms 5.0 cm or more in diameter.     

不同内径腹主动脉瘤腔内血流状况分析

目的　观察不同内径腹主动脉瘤腔内血流情况。方法　应用二维彩色多普勒超声观察不同内径和形状腹主动脉瘤患者 (2 0例 )和通过牛颈外静脉移植法 (3例 )及补片法 (3例 )制作不同内径和形状的腹主动脉瘤模型的动脉瘤腔内血流。结果　在人体中 ,动脉瘤内径≤ 3 .0cm有 5例 ,其中 4例为层流 ,动脉瘤形态为梭形。动脉瘤内径 >3 .0cm有 15例 ,其中 14例出现湍流。 3例牛颈静脉移植法建立的模型 ,当内径≤ 1.5cm时 ,血流表现为层流 ,动脉瘤形态为梭形。内径 >1.5cm时 ,动脉瘤腔内出现湍流和逆流。 3例牛颈静脉补片法建立的模型 ,在动脉瘤腔内近凸起部位出现湍流和逆流。结论　随着动脉瘤内径的增大和形状的改变 ,瘤腔内的血流更为复杂 ,可能会对动脉瘤的生长、破裂及血栓形成产生进一步的影响。     

Abdominal aortic aneurysms in Western Australia: descriptive epidemiology and patterns of rupture

All abdominal aortic aneurysms presenting to hospitals and coroners in Western Australia over an 11-year period (January 1971 to December 1981) have been reviewed. A total of 1237 abdominal aortic aneurysms were found. After age and sex standardization it was apparent that the prevalence of diagnosis of abdominal aortic aneurysms had increased from 74.8 per 100 000 to 117.2 per 100 000 for men over 55 years of age (increase of 56.7 per cent) and from 17.5 per 100 000 to 33.9 per 100 000 for women over 55 years of age (increase of 93.7 per cent) during this period. One hundred and twenty-three patients were identified by coroner's autopsy after sudden death from ruptured abdominal aortic aneurysms in whom there had been no previous diagnosis of abdominal aortic aneurysm. Between 1971 to 1981, 478 patients underwent surgery; 225 had elective resection of their aneurysm with a 4.0 per cent fatality rate, and 253 had emergency operations with a 31.2 per cent fatality rate. Seasonal variations contributing to the date of emergency presentation or death from rupture of abdominal aortic aneurysms indicated a possible influence of colder weather upon rupture. It is hoped that the information provided in this paper will be of use to surgeons and physicians involved in health care planning for similar populations.     

The surgical experience and a one to sixteen year follow-up of 277 abdominal aortic aneurysms

Between 1960 and 1975, 277 patients with abdominal aortic aneurysms were operated on at the West Virginia University Medical Center. One hundred ninety-three aneurysms were intact lesions and eighty-four were ruptured. Operative mortality for elective resection was 8.8 per cent and for ruptured aneurysms 66.7 per cent. Mortality associated with ruptured abdominal aortic aneurysms was best related to shock and advanced age. Ninety-nine per cent of patients underwent long-term follow-up which ranged from thirteen months to thirteen years and four months (mean, 4 years and 9 months). At present 61 per cent of patients surviving elective resection and 50 per cent of those surviving operation for ruptured aneurysm are alive.     

Screening of abdominal aortic aneurysm: a pragmatic approach

In order to evaluate the feasibility of a selective screening programme for abdominal aortic aneurysm (AAA) within an urban setting and assess its impact on the expected increase in workload for the local hospital(s), a population based, prospective study was performed. A total of 4823 men aged 65 years were invited for ultrasound examination of the abdominal aorta between January 1993 and April 1997 as part of a general practice-based aneurysm screening programme covering two districts with a general hospital each. All examinations were carried out by senior radiographers using a portable B mode grey scale machine and a 3.5 MHz curvi-linear array probe. Patients with a maximum aortic diameter of over 3 cm were annually recalled, those with over 4 cm were referred to hospital for an out-patient's appointment. Those with AAA greater than 5 cm were considered for surgery. Of those approached, 3497 (72.5%) took part in the study, 1206 (25%) did not attend and 120 (2.5%) were excluded by their general practitioners (GPs) on medical grounds. Of the men taking part, 3130 (89.5%) had an aortic diameter equal to or less than 2.5 cm, 196 (5.6%) between 2.6 and 3.0 cm, and 171 (4.9%) had aortic diameters greater than 3 cm--29 of whom had AAA greater than 5 cm with a mean diameter of 6.0 cm (range 5.1-9.0 cm). Of 127 men with an initial diameter of 3.1-4.0 cm (mean progression in size of 2.3 mm/year), 22 enlarged to > 4 cm and 3 to > 5 cm. Of 24 men with an initial diameter of 4.1-5.0 cm, 6 enlarged to > 5 cm. Some 69 (2%) patients were referred to hospital requiring a total of 125 consultations (1.8 consultations per patient); 21 underwent surgery and one died from rupture whilst awaiting surgery. Five patients refused their operation and two failed to attend the clinic (all > 5 cm) but remain well to date. No patient died following surgery. We conclude that, screening for AAA in men at age 65 years within an urban setting is feasible and well received by patients and GPs. Screening does not lead to a huge increase in terms of outpatient appointments and operations for AAA.     

Is assessment of popliteal artery diameter in patients undergoing screening for abdominal aortic aneurysms a worthwhile procedure.

PURPOSE: The aim of this study was to assess whether screening of popliteal arteries in patients undergoing ultrasound screening of their abdominal aortas was worthwhile. METHODS: All male patients undergoing ultrasound screening for abdominal aortic aneurysm (AAA) during the period February 2000 to June 2002 were offered scanning of their popliteal arteries. All scans were performed by a single, trained operator using a Sonosite 180. RESULTS: Four hundred and forty-nine patients underwent screening and thus 898 popliteal arteries were assessed. The mean aortic diameter was 2.1 standard deviations (SD) 0.5 cm and the upper limit of normal (2 SD) was 2.7 cm. The mean diameter of the popliteal arteries was 0.74 SD 0.11 and the upper limit of normal was 0.96 cm. Thirty patients had aortic diameters greater than 2.5 cm (ectatic or aneurysmal aortas) but based on a popliteal diameter of 2 cm, no popliteal aneurysms were detected. However, 39 (4.3%) popliteal arteries measured > or = 1 cm (> mean+2 SD); 3/60 (5%) in the ectatic/AAA subgroup and 36/838 (4.3%) in the non-AAA subgroup. CONCLUSIONS: This study has shown that, using conventional definitions, the imaging of popliteal arteries during screening for AAAs does not detect any popliteal aneurysms and is thus of limited value. However, if a definition of popliteal aneurysm of > or = 1 cm (based on mean+2 SD) is used then 39/898 (4.3%) of arteries would be regarded as having abnormal diameters and may require surveillance.     

The feasibility of screening for abdominal aortic aneurysms in a district general hospital.

The feasibility of a screening programme for abdominal aortic aneurysms within a district general hospital population is explored, based on our current accepted knowledge of the natural history of this disease process. It is shown that ultrasound screening of males aged between 65 and 74 years, with elective repair of the aneurysms discovered, could save up to 20 lives per year in this district at a reasonable and justifiable cost. Moreover, such a programme would not place an unacceptable burden on existing radiological and surgical facilities.     

Quantifying the risks of hypertension, age, sex and smoking in patients with abdominal aortic aneurysm

BACKGROUND: The prevalence of abdominal aortic aneurysm (AAA) in a community-based sample of men and women aged 65-79 years was correlated with known risk factors. In addition, the effect of high blood pressure and the use of antihypertensive medication on growth of AAAs were studied. METHODS: Aortic diameter was assessed by ultrasonography and data on risk factors were collected by self-administered questionnaire for 5356 men and women as part of a randomized controlled trial. RESULTS: Current hypertension increased the risk of having an aortic aneurysm by 30-40 per cent while use of antihypertensive medication increased the risk by 70-80 per cent, adjusting for current blood pressure. There was no clear relationship between hypertension and growth rates of existing aneurysms in this study, although these results were largely from data on small aneurysms. Men were nearly six times more likely to develop an AAA than women; the risk increased by 40 per cent every 5 years after the age of 65 years. Smoking was an independent risk factor for AAA, with level of exposure being more significant than duration. CONCLUSION: Male sex, smoking and hypertension are strong risk factors for the development of AAA. In this study hypertension did not significantly increase the growth rate of existing aneurysms. Smoking remains the most important avoidable risk factor for AAA. The analyses presented here suggest that selection for screening, other than by age and sex, is not worthwhile.     

Ruptured abdominal aortic aneurysm: factors influencing operative mortality

Of fifty-eight consecutive patients surgically treated for aneurysm of the abdominal aorta, twenty were emergency cases following the rupture. Associated diseases were found in 85 per cent of patients; hypertension being the most common. Fifty per cent of patients were in shock on admission. The duration between rupture and operation was three hrs to two weeks with the average of 115.5 hrs. In six patients, the diagnosis of abdominal aortic aneurysm was known for over six months. The operative mortality rate in case of ruptured abdominal aortic aneurysm was 45 per cent. The most important determinants of survival were the incidence of shock on admission, the incidence of associated disease, the known duration of the aneurysm, and the time interval from rupture to admission. The intraoperative factors most influencing survival were the type of rupture, intraoperative hypotension, and total blood loss. Comparison of the mortality rate in elective surgery of abdominal aortic aneurysms (5.3 per cent) with that in ruptured aneurysms (45.0 per cent) suggests the necessity for early elective operations whenever abdominal aortic aneurysms are diagnosed.     

Triumphs and tribulations in a new national screening programme for abdominal aortic aneurysm

A nationally funded aortic aneurysm screening programme for 65 year old men commenced in 2009 in England. The aim is to implement screening by commissioning local programmes covering populations of over 800,000 to a national standard. By April 2012 approximately 80 per cent of England will be covered, with the aim to complete roll out by 2013. So far, almost 100,000 65 year old men have been screened, and over 1000 abdominal aortic aneurysms detected. The incidence rate of 1.7 per cent is lower than expected, but updated calculations suggest that the programme remains cost effective. Other issues under discussion are the method of measurement of aortic diameter, and a quality assurance programme to guarantee the national standard. The key to a successful long-term programme will be its ability to remain flexible and responsive to emerging data.     

Triumphs and Tribulations in a New National Screening Programme for Abdominal Aortic Aneurysm

A nationally funded aortic aneurysm screening programme for 65 year old men commenced in 2009 in England. The aim is to implement screening by commissioning local programmes covering populations of over 800,000 to a national standard. By April 2012 approximately 80 per cent of England will be covered, with the aim to complete roll out by 2013. So far, almost 100,000 65 year old men have been screened, and over 1000 abdominal aortic aneurysms detected. The incidence rate of 1.7 per cent is lower than expected, but updated calculations suggest that the programme remains cost effective. Other issues under discussion are the method of measurement of aortic diameter, and a quality assurance programme to guarantee the national standard. The key to a successful long-term programme will be its ability to remain flexible and responsive to emerging data.     

Abdominal aortic aneurysms: should they all be resected?

A retrospective study has been carried out on 124 consecutive patients with abdominal aortic aneurysms admitted during the period 1960-74. The mortality rate after emergency operation was 56 per cent and after elective operation 15 per cent. As in other vascular centres during these years the mortality rate has decreased among electively operated patients. We have tried to answer two questions: which patients without signs of rupture should undergo operation and which patients with a ruptured aneurysm should not be operated upon?