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PREVENTION OF RUPTURED ABDOMINAL AORTIC ANEURYSM: A PROJECT TO PREVENT

SUDDEN DEATH

Salvatore Ronsivalle, MD; Francesca Faresin, MD; Francesca Franz, MD;

Department of Cardiovascular Disease – Vascular and Endovascular Surgery, Cittadella, Padua (Italy)

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ABSTRACT

BACKGROUND Abdominal aortic aneurysms are often asymptomatic but an AAA rupture is a surgical

emergency and often leads to death.

Literature data suggests that an early diagnosis is very important in the management of this pathology

and especially for obtaining emergency surgery . Recently, there has been a growing interest in the

treatment of this pathology and therefore many studies providing evidence in favor of screening for

abdominal aortic aneurysm.

METHODS The project “ AAA Aortic Abdominal Aneurysm Wanted” started in October 2007 in the

Department of Cardiovascular Disease – Vascular Surgery and Diagnostic, Cittadella, Padua (Italy)

The Main objective of the project is the prevention of death due to ruptured abdominal aortic

aneurysms and secondly to evaluate the distribution of risk factors in normal and affected populations.

RESULTS In our total study population we found 46 cases of aortic abdominal aneurysm (0.3%), 28

cases of iliac artery aneurysm (0.2%), 159 cases of aortic abdominal ectasia (1 %), 1171 cases of iliac

artery ectasia (7 %).

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In our study group we found no differences in the prevalence among the distribution of risk factors

compared with other literature data, but there was an increase in those having abdominal aortic or

iliac artery aneurysms .

CONCLUSIONS Our data confirmed the expected prevalence of asymptomatic abdominal aortic-iliac

aneurysm, revealed an elevated percentage of abdominal aortic or iliac ectasia and found a major

prevalence of aortic-liac aneurysms in first degree family members subject to a regular follow up. It

also allowed us to identify a large population based case control study group presenting a high risk of

cardiovascular disease and now it is essential to continue the study of these subjects utilizing primary

and secondary prevention plans.

Keywords : aortic abdominal aneurysm, prevention

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BACKGROUND

An Aneurysm is a permanent localised blood filled (dilation) of an artery caused by a structural

modification of the blood vessel wall. The blood vessel can burst (rupture) because the vessel wall is

weakened 1.

Abdominal aortic aneurysm (AAA) is a localized dilatation of the aorta, the main artery of the heart, as

it passes through the abdomen.

Abdominal aorta ectasia is when there is an increase of at least 50% over the normal arterial diameter

(2 cm); thus an enlargement of at least 3 cm is defined as an aneurysm.

In most cases it is a manifestation of media tunic degeneration produced by biological complex

mechanisms and literature data suggest that majority of aneurysms are due to an alteration of tissue

metalloproteinasis reducing wall integrity 8.

Atherosclerosis is the most frequent cause of abdominal aortic aneurysms and it varies according to

age, familiarity, sex, smoking, hypercholesterolemia and hypertension.

The Natural history of abdominal aneurysm is a progressive increase in the diameter : the greater the

dimension the faster they grow and there fore the higher the risk of rupture. Growing values are above

0,2 cm/year if the diameter is less than 4.5 cm and 0,5 cm/year if diameter is greater than 4.5 cm. In a

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study population of subjects over 60 years of age the prevalence of abdominal aortic aneurysm is 2-

8% and increases with age.

It’s more frequent in the male sex; the prevalence of abdominal aortic aneurysm with a diameter from

2.9 cm to 4.9 cm in males varies from 1.3 % for ages from 45 to 54 years old to 12.5% for ages from

75 to 84 years old; in the female sex it varies from 0 % for ages from 45 to 54 years old to 5.2 % for

ages from 75 to 84 years old (Fig 1).

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Over 65 years of age more than 1.7% of women and 5% of men have a dilatation of abdominal aorta

of 3 cm or more.

It is well known that Abdominal aortic aneurysms are often asymptomatic but a rupture calls for

emergency surgery and often leads to death, even if the operation is undergone immediately 1,8.

Only 18% of patients arrive still alive at the hospital and survive thel operation.

About 50% of urgent surgery has a negative prognosis, and instead 95% of planned surgery has good

results, and this percentage is increasing due to the introduction of mini-invasive endovascular

technique.

Data suggest that an early diagnosis of this pathology is very important for an optimal management

and for planning surgery in a short time.

Recently, there is more and more literature providing evidence in favor of screening for abdominal

aortic aneurysm.

Several large, randomized trials published in the past few years have consistently shown that

screening reduces abdominal aortic aneurysm-related mortality and the frequency of emergency

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operation 1,2,3,4,5,6,10,11 and support a more evidence based approach for detecting and managing

abdominal aortic aneurysm .

Results from a large pragmatic randomized trial show that the early mortality benefit of screening

ultrasonography for abdominal aortic aneurysm is maintained in the longer term and that the cost-

effectiveness of screening improves over time 6.

Current evidence on the benefits of screening men age 65 to 74 years, particularly those who have

never smoked, is sufficiently strong to suggest that this practice should evolve from guideline to quality

indicator status 7.

The proven framework of population sifting for abdominal aortic aneurysm provides a unique

opportunity to also confront latent cardiovascular malady 12.

MATERIALS AND METHODS

From October 2007 to December 2013 the project “ AAA Aortic Abdominal Aneurysm Wanted” is

operating in the Department of Cardiovascular Disease – Vascular Surgery and Diagnostic, Cittadella,

Padua (Italy). The project’s main objective is the prevention of death due to ruptured abdominal aortic

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aneurysms, by treating the asymptomatic pathology through identification, monitoring and early

planned surgery .

Other objectives are observation and study of risk factor’s distribution in normal and affected

population.

It is a seven year Project consisting of about 30.000 echocolor Doppler exams of the aortic-iliac

district, (about 4200 examinations per year). The testing of the Population is free of charge. The

Project is financed by funds donated from local public and private institutions, various Associations

and Organizations and pharmaceutical companies.

During these seven years all people from 68 to 74 years old living in our public health service area

(Fig 2), are invited for a medical history screening and to have an aorta iliac artery district

echocolordoppler.

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Yearly, we call each person from the study group who will turn 68 or 74 on their next birthday.

A detailed brochure is sent to the people aged 68 and 74 years old, living in our public health service

area along with an invitation to come to Cittadella Hospital Ambulatory of Vascular Diagnostic -

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Vascular Surgery, explaining that they must fast for at least four hours before coming to be visited. In

order to better help the people who live outside the city the local government set up a shuttle bus

service to take them to and from the Hospital.

The people are given a brief questionnaire to complete. This document is aimed at checking for

principal risk factors such as heart disease, history of cigarette smoking, obesity, high blood pressure,

diabetes, hypercholesterolemia, familiarity for abdominal aortic aneurysm, or previous cardiovascular

surgery. They are then given abdominal palpation and an aorta iliac district ecocolordoppler.

If aortic diameter is < 30 mm and/or iliac artery diameter is < 15 mm the subject is discharged and

invited to control and treat any risk factors that were found.

If aortic diameter is 30 mm - 45 mm and/or iliac artery diameter is 15-25 mm the subject is invited to

do a follow up and in the meantime to control and treat any risk factors that were found.

If aortic diameter is > 45 mm and/or iliac artery diameter is > 25 mm the subject is invited to do a

more depth analysis and to prepare for surgery using an endovascular or traditional technique (Fig 3).

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Literature’s data indicates an increased risk to develop an aortic or iliac aneurysm between first

degree family members.

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A study made in Ireland from 1990 to 1993 showed that in 12% of male siblings of patients with

abdominal aortic aneurysm had also an aortic abdominal aneurysm and Cole et all. suggested a sex

linked transmission in males 13,14.

A group of researchers from the Karolinska Institutet, Stockholm, Sweden said that there is a higher

risk if the patient has several relatives with abdominal aortic aneurysm, if the aneurysm is diagnosed

in early age, the gender does not influence the risk, the increased risk with several relatives is

compatible with a multigenetic pathogenesis and that the risk may be underestimated due to

unreported cases with ruptured aortic aneurysm and unrecognised relatives 15.

After evaluating these theories, we decided to extend the screening by doing an aortic-iliac district

echocolordoppler to family members over 60 years of age

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RESULTS

From October 2007 to December 2013 25720 persons which represent all people who had turned 68

and 74 years old living in our public health service area that had been invited to do a medical history

screening and aorto iliac district echocolordoppler.

At the end of the second year of the project, 16685 aorto iliac district echocolordoppler exams were

given to about 25720 invited people with a mean attendance of 64,8 %. (Fig 4).

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There was a shuttle bus service, organized in collaboration with local governments , to take people

who lived outside the city to and from the Cittadella Hospital.

In total study population (16685 ) we found: 46 cases of aortic abdominal aneurysm (0.3%), 28 cases

of iliac artery aneurysm (0.2%), 159 cases of aortic abdominal ectasia (1 %), 1171 cases of iliac artery

ectasia (7%) (Tab 1).

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In group of 46 abdominal aortic aneurysm: 42 underwent EVAR , 1 died for an acute pancreatitis, after

9 months, and 3 are stable in follow up (Tab 2).

In group of 28 iliac aortic aneurysm: 19 underwent EVAR , 7 are actually stable in follow up, 2 was

unavailable for follow-up (Tab 2).

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In total study population (16685) prevalence of risk factor’s distribution is: heart disease 1846 (11 %),

obesity 4776 (28.6 %), hypercholesterolemia 6423 (38.5 %), diabetes 2433 (14.6%), high blood

pressure 10366 (62.2 %), smoke 796 (4.8 %), previous cardiovascular surgery 796 (4.8 %), familiarity

for abdominal aortic aneurysm 255 (1.5 %) (Fig 5).

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In abdominal aortic or iliac aneurysm affected total population (74) prevalence of risk factor’s

distribution is: heart disease 30 (40.5 %), obesity 31 (41.9 %), hypercholesterolemia 10 (35.7 %),

diabetes 24 (32.4 %), high blood pressure 43 (58.1 %), smoke 23 (31 %), previous cardiovascular

surgery 22 (29.7 %), familiarity for abdominal aortic aneurysm 18 (24.3 %) (Fig 6).

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In abdominal aortic or iliac artery ectasia affected total population (1330) prevalence of risk factor’s

distribution is: heart disease 197 (14.8 %), obesity 342 (25.7 %), hypercholesterolemia 392 (29.5 %),

diabetes 151 (11.4 %), high blood pressure 655 (49.2 %), smoke 87 (6.5%) previous cardiovascular

surgery 82 (6.1 %), familiarity for abdominal aortic aneurysm 24 (1.8 %) (Fig 7).

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DISCUSSION

The results of the data after one year of “ AAA Aortic Abdominal Aneurysm Wanted” demonstrated

that in the 16685 persons studied , we found 74 cases (0.44 %), of abdominal aortic aneurysm, and

1330 cases of aorto iliac artery ectasia (8 %), so the prevalence of pathology is in accordance with

literature data (4.4%).

More than likely, this data underestimates the real prevalence in our geographical area because we

had examined only two extremes of identified age (only people aged 68 and 74).

We reached our target of identifying carriers of asymptomatic abdominal aortic aneurysm of which

were treated with early surgery planned treatment (endovascular or traditional surgery).

We identified 1330 cases of abdominal aortic or iliac ectasia which have an increased risk to turn into

an aneurysm and are therefore subject to a regular follow up.

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We found an elevated prevalence of aortic or iliac aneurysm in first degree family members (1.8%) in

agreement with literature (12%), so we believe that it is essential to extend the screening with an

aorto-iliac district echocolordoppler to first degree family members who have turned 60.

Working out prevalence of major risk factor’s distribution in normal and affected populations (which is

super imposable with literature data) lets us come to the conclusion that it is not only associated with

a major risk to have an aortic-iliac aneurysm, but it also allows us to identify a large part of a

population having a high risk of presenting a cardiovascular pathology to be subject to a regular

primary and secondary prevention plan. (Fig 8).

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CONCLUSIONS

Death due to breaking abdominal aortic or iliac aneurysm is the thirteenth cause of death in western

countries.

Recently, over the past to years, many studies have demonstrated a rising trend in the prevalence and

incidence of this pathology.

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The Projects main objective is and remains the prevention of death due to the rupturing of abdominal

aortic aneurysms by identifying , monitoring and the planning of early surgery when treating this

asymptomatic pathology.

Analysing the data confirmed the expected occurence of asymptomatic abdominal aortic aneurysm

being treatable with early planned surgery (endovascular or traditional), revealed an elevated

percentage of abdominal aortic or iliac ectasia which is helpful in advising subjects to have a regular

follow up and found an elevated prevalence of aortic or iliac aneurysm in first degree family members.

We think it is essential to continue to invest money, time, doctors, and nurses in the development of

the project “ AAA Aortic Abdominal Aneurysm wanted” as a medical screening for people from 68 to

74 years old living in our public health service area and its surroundings “” AAA FOLLOW UP ” for

aortic-iliac ectasia’s follow up and “ AAA FAMILY” for aortic-iliac aneurysm carriers first degree family

members who are 60 years or older (Fig 9).

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It is very important to underline the fact that the data we have been able to obtain regarding the

distribution of the prevalence of risk factors in normal and affected populations have allowed us to

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identify an elevated percentage of persons having a high risk of encountering a cardiovascular

disease and therefore able to include them in a regular primary and secondary prevention plan.

Moreover, the Worldwide Health Organization has said that in 20 years about 25% of the world’s

population will have some kind of cardiovascular disease and the cost of medical aid will be very

expensive.

Therefore we stress the fact that it is fundamental to continue to invest money, time, work, Doctors

and nurses in this prevention project. It is of extreme importance to continue what we have started, to

give the population the instruments with which to develop more screening. The possibility to undergo

primary and secondary medical examinations, follow ups which can save their lives and lives of

someone in their family. Our Cardiovascular Divisions should have these programs as a part of their

routine.

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REFERENCES

1) Cosford PA, Leng GC, Screening trial for abdominal aortic aneurysm (Review) Cochrane Database

of systematic reviews 2007, Issue Art No CD 002945. DOI 10.1002/14651858. CD 002945.pub2

2) Lindholt JS, Juul S, Fasting H, Henneberg E.W. Preliminary ten year results from a randomised

single centre mass screening trial for abdominal aortic aneurysm Eur J Vasc Endovasc Surgery 32,

608-614 (2006) )

3) Lindholt JS, Juul S, Henneberg EW Hight risk and low risk screening for abdominal aortic aneurysm

both reduce aneuryism related mortality. A stratified analysis from a single centre randomised

screening trial Eur J Vasc Endovasc Surg 34, 53-58 (2007)

4) U.S. preventive Services task Force. Screening for Abdominal Aortic Aneurysm: raccomendation

Statement. Annals of Internal Medicine 2005, 142, 3: 198 -202

5) Multicentre Aneurysm Screening Study Group. The multicentre Aneurysm Screening Study (MASS)

into the effect of abdominal aortic aneurysm screening on mortality in men : a randomized controlled

trial. Lancet . 2002 ; 360 : 1531-9.

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6) Kim LG, Scott AP, Ashton HA, Thompson SG for the Multicentre Aneurysm Screening Study Group

A Sustained Mortality benefit from screening for Abdominal Aortic Aneurysm. Annals of Internal

Medicine 2007, 2007 ; 146, 10: 699-706

7) Birkmeyer JD, Upchurch GR Jr. Evidence Based Screening and Management of Abdominal Aortic

Aneurysm. Annals of Internal Medicine 2007, 146, 10: 749-750.

8) Lovell MB, Harris KA, Guy de Rose , MD, Forbes TL, Fortier M, Scott B. A screening program to

identify risk factors for abdominal aortic aneurysm. Can J Surg, Vol 49, No 2, April 2006

9) Lindholt JS, Norman P. Screening for abdominal aortic aneurysm reduces overall mortality in men.

A meta-analysis of the mid - and long- term effects of screeening fo abdomial aortic aneurysm . Eur J

Vasc Endovasc Surg 2008, 36, 167-171

10) Montreuil B, Brophy J. Screening for abdominal aortic aneurysm in men : a Canadian perspective

using Monte Carlo-based estimates Can J Surg, vol 51, No 1 February 2008

11) Ashton HA, Gao L, Kim LG ; Druce PS, Thompson SG, Scott RAP Fifteeen –year follow up of a

randomized clinical trial of ultrasonographic screening for abdominal aortic aneurysm British Journal

of Surgery 2007 ; 94. 696-701

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12) Waterhouse DF, Cahill RA. Simple adaptation of current abdominal aortic aneurysm screening

programs may address all-cause cardiovascular mortality : prospective observationale cohort study.

Am Heart J 2008 ; 155 : 938-45

13) Fizgerald P, Ramsbottom D, Burke P, et al. Abdominal aortic aneurysm in the Irish population: a

familial screening study. Br J Surg 1995; 82:483-6

14) Cole CW, Barber GC, Bouchard AG; et al. Abdominal aortic aneurysm: consequences of a

positive family history. Can J Surg 1989; 32: 117-20

15) Larsson E, Familial risk of aortic aneurysm. Vascular News September 2008