Abdominal Aortic Aneurysm

1 538 American Family Physician Volume 91, Number 8 April 15, 2015 Abdominal Aortic AneurysmBRIAN KEISLER, MD, and CHUCK CARTER, MD, University of South Carolina School of Medicine, Columbia, South Carolinabdominal Aortic Aneurysm (AAA) is an Abdominal Aortic dilation of cm or The prevalence of AAA increases with age. It is uncommon in persons younger than 50 years; however, of men and of women 74 to 84 years of age have It accounts for approximately 11,000 deaths each year in the United States, with mortality rates from ruptured AAAs reaching up to 90%.2 aneurysms develop as a result of degen-eration of the arterial media and elastic Risk factors for AAA are similar to those of other cardiovascular diseases.

2 The key risk factors are male sex, smoking, age older than 65 years, coronary artery disease, hypertension, previous myocardial infarc-tion, peripheral arterial disease, and a family history of AAA1,3,4 (Ta b l e 12,3). Blacks appear to be at lower the inherent risk of rupture, patients with AAA are also at an increased risk of cardiovascular disease and death independent of other The degree to which risk factors impact AAA vs. athero-sclerosis varies. For example, dyslipidemia is an important coronary artery disease risk factor, although its role in AAA remains uncertain, and diabetes mellitus may have a negative association with ,4 PresentationPhysical examination with Abdominal pal-pation is only moderately sensitive for the detection of AAA, with one study demon-strating a sensitivity of 68% and specificity of 75%.

3 6 The most common finding is pal-pation of a pulsatile mass around the level of the umbilicus. Abdominal auscultation may reveal the presence of a bruit. The accu-racy of Abdominal palpation is reduced by obesity, Abdominal distention, and smaller Aneurysm size. In particular, Abdominal girth greater than 100 cm ( in) is asso-ciated with decreased sensitivity for identi-fication with An Aneurysm may rarely produce findings related to compres-sion of adjacent structures, such as lower extremity edema related to compression of the inferior vena of AAA is often made as an incidental finding on imaging studies, such Abdominal Aortic Aneurysm refers to Abdominal Aortic dilation of cm or greater.

4 The main risk factors are age older than 65 years, male sex, and smoking history. Other risk factors include a family history of Abdominal aor-tic Aneurysm , coronary artery disease, hypertension, peripheral artery disease, and previous myocardial infarction. Diagnosis may be made by physical examination, an incidental finding on imaging, or ultrasonography. The Preventive Services Task Force released updated recommendations for Abdominal Aortic Aneurysm screening in 2014. Men 65 to 75 years of age with a history of smoking should undergo one-time screening with ultrasonography based on evidence that screening will improve Abdominal Aortic Aneurysm related mortality in this population.

5 Men in this age group without a history of smoking may benefit if they have other risk factors ( , family history of Abdominal Aortic Aneurysm , other vascular aneurysms , coronary artery disease). There is inconclusive evidence to recommend screening for Abdominal Aortic Aneurysm in women 65 to 75 years of age with a smoking history. Women without a smoking history should not undergo screening because the harms likely outweigh the benefits. Persons who have a stable Abdominal Aortic Aneurysm should undergo regular surveillance or operative intervention depending on aneu-rysm size. Surgical intervention by open or endovascular repair is the primary option and is typically reserved for aneurysms cm in diameter or greater.

6 There are limited options for medical treatment beyond risk factor modifica-tion. Ruptured Abdominal Aortic Aneurysm is a medical emergency presenting with hypotension, shooting Abdominal or back pain, and a pulsatile Abdominal mass. It is associated with high prehospitalization mortality. Emergent surgi-cal intervention is indicated for a rupture but has a high operative mortality rate. (Am Fam Physician. 2015 ; 91(8) :538-543. Copyright 2015 American Academy of Family Physicians.) See related editorial on page 518, Putting Prevention into Practice on page 563, and Preventive Services Task Force recommen-dation statement at /2015/ 0415 This clinical content conforms to AAFP criteria for continuing medical education (CME).

7 See CME Quiz Questions on page disclosure: No rel-evant financial from the American Family Physician website at Copyright 2014 American Academy of Family Physicians. For the private, noncom-mercial use of one individual user of the website. All other rights reserved. Contact for copyright questions and/or permission Aortic AneurysmApril 15, 2015 Volume 91, Number 8 American Family Physician 539as Abdominal ultrasonography or computed tomography (Figures 1 and 2). AAA may occasionally be visible on plain radiography, if the Aneurysm wall is ruptured AAA is a medical emergency associated with high mortality rates. The classic syndrome is char-acterized by hypotension, shooting Abdominal or back pain, and a pulsatile Abdominal mass.

8 This triad may be incomplete or absent, and misdiagnosis can occur in up to 60% of cases. Therefore, physicians must be mind-ful of atypical presentations and attentive to new-onset, nonspecific back or Abdominal pain in patients at risk of AAA is most often clinically silent, screening can improve detection. Ultrasonography has a high sen-sitivity and specificity (95% and nearly 100%, respec-tively) for detecting AAA when performed in a setting experienced in the use of ,9 Addition-ally, there are no significant harms associated with Abdominal Although larger studies are needed, preliminary data suggest that family physi-cians can be trained to successfully screen for AAA in the office randomized, controlled, population-based stud-ies provide much of the available data on AAA The Multicentre Aneurysm Screening Study was the largest, following approximately 70,000 men between 65 and 74 years of age for 10 Partici-pants were randomized to an offer of ultrasonography or to a control group.

9 Those with AAA detected at screening were followed by ultrasound surveillance or elective surgery based on predefined criteria. The reduc-tion in AAA-related mortality improved from 42% at four-year follow-up to 48% at 10-year follow-up, dem-onstrating continued benefit over the duration of the SORT: KEY RECOMMENDATIONS FOR PRACTICEC linical recommendationEvidence ratingReferencesOne-time screening for AAA with ultrasonography should be performed in men 65 to 75 years of age who have smoked 100 cigarettes or more in their 4, 9 One-time screening for AAA with ultrasonography should be selectively offered in men 65 to 75 years of age who have never smoked, but have risk factors for evidence is insufficient to recommend for or against AAA screening in women 65 to 75 years of age who have smoked 100 cigarettes or more in their screening should not be performed in women who have never smoked.

10 B9 Patients with AAAs to cm in diameter should be monitored with ultrasonography every two to three with AAAs to cm in diameter should be monitored with ultrasonography or computed tomography every six to 12 = Abdominal Aortic = consistent, good-quality patient-oriented evidence; B = inconsistent or limited-quality patient-oriented evidence; C = consensus, disease-oriented evidence, usual practice, expert opinion, or case series. For information about the SORT evidence rating system, go to 1. Risk Factors for Abdominal Aortic AneurysmAtherosclerosis Cerebrovascular disease Coronary artery disease First-degree relative with Abdominal Aortic aneurysmHistory of other vascular aneurysms Hypercholesterolemia HypertensionMale sex*Obesity Older age* Tobacco use** These risk factors are stressed by the Preventive Services Task Force in terms of need for screening (men 65 to 75 years of age with a lifetime smoking history of at least 100 cigarettes).