Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate®

Overview of abdominal aortic aneurysm

Ronald L Dalman, MD
Matthew Mell, MD, FACS
Section Editors
John F Eidt, MD
Joseph L Mills, Sr, MD
Deputy Editor
Kathryn A Collins, MD, PhD, FACS


Mortality remains high for patients who experience rupture of an abdominal aortic aneurysm (AAA), but it has dropped considerably in the past 20 years due to a variety of factors [1]. Elective AAA repair prior to the development of symptoms is the most effective means to prevent rupture and aneurysm-related sudden death.

The definition of abdominal aortic aneurysm and aortic anatomy will be reviewed here together with an overview of the epidemiology, risk factors, pathogenesis, natural history, screening, clinical features and diagnosis, management, and surgical repair, with links to more detailed topics. Other types of arterial aneurysms are discussed separately.


Abdominal aortic aneurysm (AAA) is the most common true arterial aneurysm. A true aneurysm is defined as a segmental, full-thickness dilation of a blood vessel that is 50 percent greater than the normal aortic diameter (figure 1) [2]. False aneurysms of the abdominal aorta can also occur but are much less common and are usually due to a traumatic or infectious etiology.

In most adults, an aortic diameter >3.0 cm is generally considered aneurysmal. Normal aortic diameter varies with age, gender, and body habitus, but the average diameter of the adult human infrarenal aorta is approximately 2.0 cm; 95 percent of the adult population has an aortic diameter ≤3.0 cm [2]. Thus, for the majority of patients, an infrarenal aorta with a maximum diameter ≥3.0 cm is considered aneurysmal [2-4]. For men, diameter alone defines the presence of an AAA and predicts clinical events. However, for women, although the aorta is still considered aneurysmal when its diameter exceeds 3.0 cm, the diameter is less predictive of clinical events. An aortic scaling index (ASI), calculated as diameter (cm)/body surface area (m2), is more predictive of clinical events than absolute aortic diameter in women [5].

For the purposes of this discussion:


Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Jul 2017. | This topic last updated: Jul 24, 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. Stather PW, Sidloff DA, Rhema IA, et al. A review of current reporting of abdominal aortic aneurysm mortality and prevalence in the literature. Eur J Vasc Endovasc Surg 2014; 47:240.
  2. Johnston KW, Rutherford RB, Tilson MD, et al. Suggested standards for reporting on arterial aneurysms. Subcommittee on Reporting Standards for Arterial Aneurysms, Ad Hoc Committee on Reporting Standards, Society for Vascular Surgery and North American Chapter, International Society for Cardiovascular Surgery. J Vasc Surg 1991; 13:452.
  3. Hirsch AT, Haskal ZJ, Hertzer NR, et al. ACC/AHA 2005 Practice Guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Peripheral Arterial Disease): endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation; National Heart, Lung, and Blood Institute; Society for Vascular Nursing; TransAtlantic Inter-Society Consensus; and Vascular Disease Foundation. Circulation 2006; 113:e463.
  4. Chaikof EL, Brewster DC, Dalman RL, et al. The care of patients with an abdominal aortic aneurysm: the Society for Vascular Surgery practice guidelines. J Vasc Surg 2009; 50:S2.
  5. Lo RC, Lu B, Fokkema MT, et al. Relative importance of aneurysm diameter and body size for predicting abdominal aortic aneurysm rupture in men and women. J Vasc Surg 2014; 59:1209.
  6. Sweeting MJ, Thompson SG, Brown LC, et al. Meta-analysis of individual patient data to examine factors affecting growth and rupture of small abdominal aortic aneurysms. Br J Surg 2012; 99:655.
  7. Evans GH, Stansby G, Hamilton G. Suggested standards for reporting on arterial aneurysms. J Vasc Surg 1992; 15:456.
  8. Chiesa R, Tshomba Y, Mascia D, et al. Open repair for juxtarenal aortic aneurysms. J Cardiovasc Surg (Torino) 2013; 54:35.
  9. Chaikof EL, Blankensteijn JD, Harris PL, et al. Reporting standards for endovascular aortic aneurysm repair. J Vasc Surg 2002; 35:1048.
  10. Stanley, J. Open surgical treatment of pararenal abdominal aortic aneurysms. In: Aortic Aneurysms, Contemporary Cardiology, Upchurch, G, Criado, E (Eds), Humana Press, 2009. p.159.
  11. Chaikof EL, Brewster DC, Dalman RL, et al. SVS practice guidelines for the care of patients with an abdominal aortic aneurysm: executive summary. J Vasc Surg 2009; 50:880.
  12. Sandhu RS, Pipinos II. Isolated iliac artery aneurysms. Semin Vasc Surg 2005; 18:209.
  13. Kent KC, Zwolak RM, Egorova NN, et al. Analysis of risk factors for abdominal aortic aneurysm in a cohort of more than 3 million individuals. J Vasc Surg 2010; 52:539.
  14. Mussa FF. Screening for abdominal aortic aneurysm. J Vasc Surg 2015; 62:774.
  15. Singh K, Bønaa KH, Jacobsen BK, et al. Prevalence of and risk factors for abdominal aortic aneurysms in a population-based study : The Tromsø Study. Am J Epidemiol 2001; 154:236.
  16. Powell JT, Greenhalgh RM. Clinical practice. Small abdominal aortic aneurysms. N Engl J Med 2003; 348:1895.
  17. Scott RA, Ashton HA, Kay DN. Abdominal aortic aneurysm in 4237 screened patients: prevalence, development and management over 6 years. Br J Surg 1991; 78:1122.
  18. Lederle FA, Johnson GR, Wilson SE, et al. Prevalence and associations of abdominal aortic aneurysm detected through screening. Aneurysm Detection and Management (ADAM) Veterans Affairs Cooperative Study Group. Ann Intern Med 1997; 126:441.
  19. Boll AP, Verbeek AL, van de Lisdonk EH, van der Vliet JA. High prevalence of abdominal aortic aneurysm in a primary care screening programme. Br J Surg 1998; 85:1090.
  20. Svensjö S, Björck M, Gürtelschmid M, et al. Low prevalence of abdominal aortic aneurysm among 65-year-old Swedish men indicates a change in the epidemiology of the disease. Circulation 2011; 124:1118.
  21. Lederle FA. The rise and fall of abdominal aortic aneurysm. Circulation 2011; 124:1097.
  22. Schermerhorn ML, Buck DB, O'Malley AJ, et al. Long-Term Outcomes of Abdominal Aortic Aneurysm in the Medicare Population. N Engl J Med 2015; 373:328.
  23. Gadowski GR, Pilcher DB, Ricci MA. Abdominal aortic aneurysm expansion rate: effect of size and beta-adrenergic blockade. J Vasc Surg 1994; 19:727.
  24. Mortality results for randomised controlled trial of early elective surgery or ultrasonographic surveillance for small abdominal aortic aneurysms. The UK Small Aneurysm Trial Participants. Lancet 1998; 352:1649.
  25. Brady AR, Thompson SG, Fowkes FG, et al. Abdominal aortic aneurysm expansion: risk factors and time intervals for surveillance. Circulation 2004; 110:16.
  26. Vega de Céniga M, Gómez R, Estallo L, et al. Growth rate and associated factors in small abdominal aortic aneurysms. Eur J Vasc Endovasc Surg 2006; 31:231.
  27. Lederle FA, Johnson GR, Wilson SE, et al. Relationship of age, gender, race, and body size to infrarenal aortic diameter. The Aneurysm Detection and Management (ADAM) Veterans Affairs Cooperative Study Investigators. J Vasc Surg 1997; 26:595.
  28. Brewster DC, Cronenwett JL, Hallett JW Jr, et al. Guidelines for the treatment of abdominal aortic aneurysms. Report of a subcommittee of the Joint Council of the American Association for Vascular Surgery and Society for Vascular Surgery. J Vasc Surg 2003; 37:1106.
  29. Newman AB, Arnold AM, Burke GL, et al. Cardiovascular disease and mortality in older adults with small abdominal aortic aneurysms detected by ultrasonography: the cardiovascular health study. Ann Intern Med 2001; 134:182.
  30. Collin J, Araujo L, Walton J, Lindsell D. Oxford screening programme for abdominal aortic aneurysm in men aged 65 to 74 years. Lancet 1988; 2:613.
  31. Thompson AR, Cooper JA, Ashton HA, Hafez H. Growth rates of small abdominal aortic aneurysms correlate with clinical events. Br J Surg 2010; 97:37.
  32. Scott RA, Wilson NM, Ashton HA, Kay DN. Influence of screening on the incidence of ruptured abdominal aortic aneurysm: 5-year results of a randomized controlled study. Br J Surg 1995; 82:1066.
  33. Fleming C, Whitlock EP, Beil TL, Lederle FA. Screening for abdominal aortic aneurysm: a best-evidence systematic review for the U.S. Preventive Services Task Force. Ann Intern Med 2005; 142:203.
  34. Ashton HA, Buxton MJ, Day NE, et al. The Multicentre Aneurysm Screening Study (MASS) into the effect of abdominal aortic aneurysm screening on mortality in men: a randomised controlled trial. Lancet 2002; 360:1531.
  35. Norman PE, Jamrozik K, Lawrence-Brown MM, et al. Population based randomised controlled trial on impact of screening on mortality from abdominal aortic aneurysm. BMJ 2004; 329:1259.
  36. Lindholt JS, Juul S, Fasting H, Henneberg EW. Hospital costs and benefits of screening for abdominal aortic aneurysms. Results from a randomised population screening trial. Eur J Vasc Endovasc Surg 2002; 23:55.
  37. Lindholt JS, Juul S, Fasting H, Henneberg EW. Screening for abdominal aortic aneurysms: single centre randomised controlled trial. BMJ 2005; 330:750.
  38. Cosford PA, Leng GC. Screening for abdominal aortic aneurysm. Cochrane Database Syst Rev 2007; :CD002945.
  39. Scott RA. Priorities in the management of abdominal aortic aneurysm. Br J Surg 2007; 94:653.
  40. Fink HA, Lederle FA, Roth CS, et al. The accuracy of physical examination to detect abdominal aortic aneurysm. Arch Intern Med 2000; 160:833.
  41. Akkersdijk GJ, van Bockel JH. Ruptured abdominal aortic aneurysm: initial misdiagnosis and the effect on treatment. Eur J Surg 1998; 164:29.
  42. Gloviczki P, Pairolero PC, Mucha P Jr, et al. Ruptured abdominal aortic aneurysms: repair should not be denied. J Vasc Surg 1992; 15:851.
  43. Rinckenbach S, Albertini JN, Thaveau F, et al. Prehospital treatment of infrarenal ruptured abdominal aortic aneurysms: a multicentric analysis. Ann Vasc Surg 2010; 24:308.
  44. Marston WA, Ahlquist R, Johnson G Jr, Meyer AA. Misdiagnosis of ruptured abdominal aortic aneurysms. J Vasc Surg 1992; 16:17.
  45. LaRoy LL, Cormier PJ, Matalon TA, et al. Imaging of abdominal aortic aneurysms. AJR Am J Roentgenol 1989; 152:785.
  46. Mehta M, Taggert J, Darling RC 3rd, et al. Establishing a protocol for endovascular treatment of ruptured abdominal aortic aneurysms: outcomes of a prospective analysis. J Vasc Surg 2006; 44:1.
  47. Chien DK, Chang WH, Yeh YH. Radiographic findings of a ruptured abdominal aortic aneurysm. Circulation 2010; 122:1880.
  48. Boules TN, Compton CN, Stanziale SF, et al. Can computed tomography scan findings predict "impending'' aneurysm rupture? Vasc Endovascular Surg 2006; 40:41.
  49. Siegel CL, Cohan RH, Korobkin M, et al. Abdominal aortic aneurysm morphology: CT features in patients with ruptured and nonruptured aneurysms. AJR Am J Roentgenol 1994; 163:1123.
  50. Arita T, Matsunaga N, Takano K, et al. Abdominal aortic aneurysm: rupture associated with the high-attenuating crescent sign. Radiology 1997; 204:765.
  51. Mehard WB, Heiken JP, Sicard GA. High-attenuating crescent in abdominal aortic aneurysm wall at CT: a sign of acute or impending rupture. Radiology 1994; 192:359.
  52. Welch HG, Albertsen PC, Nease RF, et al. Estimating treatment benefits for the elderly: the effect of competing risks. Ann Intern Med 1996; 124:577.
  53. Lederle FA, Wilson SE, Johnson GR, et al. Immediate repair compared with surveillance of small abdominal aortic aneurysms. N Engl J Med 2002; 346:1437.
  54. Cao P, De Rango P, Verzini F, et al. Comparison of surveillance versus aortic endografting for small aneurysm repair (CAESAR): results from a randomised trial. Eur J Vasc Endovasc Surg 2011; 41:13.
  55. Ouriel K, Clair DG, Kent KC, et al. Endovascular repair compared with surveillance for patients with small abdominal aortic aneurysms. J Vasc Surg 2010; 51:1081.
  56. United Kingdom EVAR Trial Investigators, Greenhalgh RM, Brown LC, et al. Endovascular repair of aortic aneurysm in patients physically ineligible for open repair. N Engl J Med 2010; 362:1872.
  57. http://content.onlinejacc.org/cgi/reprint/47/6/e1.pdf (Accessed on March 23, 2010).
  58. Sieunarine K, Lawrence-Brown MM, Goodman MA. Comparison of transperitoneal and retroperitoneal approaches for infrarenal aortic surgery: early and late results. Cardiovasc Surg 1997; 5:71.