What are the SVS treatment guidelines for unruptured abdominal aortic aneurysm (AAA)?

Answer

Even patients who do not have symptoms from their AAAs may eventually require surgical intervention because the result of medical management in this population is a mortality of 100% over time as a consequence of rupture. In addition, these patients have a potential for limb loss from peripheral embolization.

The decision to treat an unruptured AAA is based on operative risk, the risk of rupture, and the patient’s estimated life expectancy. In 2009, the Society for Vascular Surgery (SVS) published a series of guidelines for the treatment of AAAs based on these principles.^[20]

Operative risk is based on patients’ comorbidities and hospital factors (see Table 1 below). Patient characteristics, including age, sex, renal function, and cardiopulmonary disease are perhaps the most important factors. However, lower-volume hospitals and surgeons are associated with higher mortality.^[21]

Table 1. Operative Mortality Risk With Open Repair of Abdominal Aortic Aneurysm (Open Table in a new window)

</tbody>

Lowest Risk	Moderate Risk	High Risk
Age <70 y	Age 70-80 y	Age 80 y
Physically active	Active	Inactive, poor stamina
No clinically overt cardiac disease	Stable coronary disease; remote MI; LVEF >35%	Significant coronary disease; recent MI; frequent angina; CHF; LVEF < 25%
No significant comorbidities	Mild COPD	Limiting COPD; dyspnea at rest; O₂ dependency; FEV₁</td></tr>
...	Creatinine 2.0-3.0 mg/dL	...
Normal anatomy	Adverse anatomy or AAA characteristics	Creatinine >3 mg/dL
No adverse AAA characteristics	...	Liver disease (↑PT; albumin </td></tr>
Anticipated operative mortality, 1-3%	Anticipated operative mortality, 3-7%	Anticipated operative mortality, at least 5-10%; each comorbid condition adds ~3-5% mortality risk
AAA = abdominal aortic aneurysm; CHF = chronic heart failure; COPD = chronic obstructive pulmonary disease; FEV₁ = forced expiratory volume in 1 second; LVEF = left ventricular ejection fraction; MI = myocardial infarction; PT = prothrombin time.

Abdominal ultrasonography can provide a preliminary determination of the aneurysm’s presence, size, and extent. Rupture risk is in part indicated by the size of the aneurysm (see Table 2 below).

Table 2. Abdominal Aortic Aneurysm Size and Estimated Annual Risk of Rupture (Open Table in a new window)

AAA Diameter (cm)	Rupture Risk (%/y)
<4	0
4-5	0.5-5
5-6	3-15
6-7	10-20
7-8	20-40
>8	30-50
AAA = abdominal aortic aneurysm.

In addition to aneurysm diameter, factors such as sex, aneurysm expansion rate, family history, and chronic obstructive pulmonary disease (COPD) also affect the risk of rupture (see Table 3 below).

Table 3. Factors Affecting Risk of Abdominal Aortic Aneurysm Rupture (Open Table in a new window)

Factor	Low Risk	Average Risk	High Risk
Diameter	<5 cm	5-6 cm	>6 cm
Expansion	<0.3 cm/y	0.3-0.6 cm/y	>0.6 cm/y
Smoking/COPD	None, mild	Moderate	Severe/steroids
Family history	No relatives	One relative	Numerous relatives
Hypertension	Normal blood pressure	Controlled	Poorly controlled
Shape	Fusiform	Saccular	Very eccentric
Wall stress	Low (35 N/cm²	Medium (40 N/cm²	High (45 N/cm²)
Sex	...	Male	Female
COPD = chronic obstructive pulmonary disease.

Did this answer your question?

Yes No

Additional feedback? (Optional)

Thank you for your feedback!

Blanchard JF, Armenian HK, Friesen PP. Risk factors for abdominal aortic aneurysm: results of a case-control study. Am J Epidemiol. 2000 Mar 15. 151(6):575-83. [Medline].
Lederle FA, Johnson GR, Wilson SE, Chute EP, Littooy FN, Bandyk D, 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 Mar 15. 126(6):441-9. [Medline].
Wassef M, Baxter BT, Chisholm RL, Dalman RL, Fillinger MF, Heinecke J, et al. Pathogenesis of abdominal aortic aneurysms: a multidisciplinary research program supported by the National Heart, Lung, and Blood Institute. J Vasc Surg. 2001 Oct. 34(4):730-8. [Medline].
[Guideline] U.S. Preventive Services Task Force. Screening for abdominal aortic aneurysm: recommendation statement. Ann Intern Med. 2005 Feb 1. 142(3):198-202. [Medline]. [Full Text].
[Guideline] LeFevre ML, U.S. Preventive Services Task Force. Screening for abdominal aortic aneurysm: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2014 Aug 19. 161 (4):281-90. [Medline]. [Full Text].
Guirguis-Blake JM, Beil TL, Senger CA, Whitlock EP. Ultrasonography screening for abdominal aortic aneurysms: a systematic evidence review for the U.S. Preventive Services Task Force. Ann Intern Med. 2014 Mar 4. 160(5):321-9. [Medline].
Svensjö S, Björck M, Gürtelschmid M, Djavani Gidlund K, Hellberg A, Wanhainen A. Low prevalence of abdominal aortic aneurysm among 65-year-old Swedish men indicates a change in the epidemiology of the disease. Circulation. 2011 Sep 6. 124(10):1118-23. [Medline].
Majumder PP, St Jean PL, Ferrell RE, Webster MW, Steed DL. On the inheritance of abdominal aortic aneurysm. Am J Hum Genet. 1991 Jan. 48(1):164-70. [Medline]. [Full Text].
Tilson MD, Ozsvath KJ, Hirose H, Xia S. A genetic basis for autoimmune manifestations in the abdominal aortic aneurysm resides in the MHC class II locus DR-beta-1. Ann N Y Acad Sci. 1996 Nov 18. 800:208-15. [Medline].
FDA warns about increased risk of ruptures or tears in the aorta blood vessel with fluoroquinolone antibiotics in certain patients. US Food and Drug Administration. Available at https://www.fda.gov/Drugs/DrugSafety/ucm628753.htm. December 20, 2018; Accessed: January 8, 2019.
Ambler GK, Gohel MS, Mitchell DC, Loftus IM, Boyle JR, Audit and Quality Improvement Committee of the Vascular Society of Great Britain and Ireland. The Abdominal Aortic Aneurysm Statistically Corrected Operative Risk Evaluation (AAA SCORE) for predicting mortality after open and endovascular interventions. J Vasc Surg. 2015 Jan. 61 (1):35-43. [Medline].
Von Allmen RS, Powell JT. The management of ruptured abdominal aortic aneurysms: screening for abdominal aortic aneurysm and incidence of rupture. J Cardiovasc Surg (Torino). 2012 Feb. 53(1):69-76. [Medline].
Anjum A, von Allmen R, Greenhalgh R, Powell JT. Explaining the decrease in mortality from abdominal aortic aneurysm rupture. Br J Surg. 2012 May. 99(5):637-45. [Medline].
Daly KJ, Torella F, Ashleigh R, McCollum CN. Screening, diagnosis and advances in aortic aneurysm surgery. Gerontology. 2004 Nov-Dec. 50(6):349-59. [Medline].
Blaivas M, Theodoro D. Frequency of incomplete abdominal aorta visualization by emergency department bedside ultrasound. Acad Emerg Med. 2004 Jan. 11(1):103-5. [Medline].
Bobadilla JL, Suwanabol PA, Reeder SB, Pozniak MA, Bley TA, Tefera G. Clinical implications of non-contrast-enhanced computed tomography for follow-up after endovascular abdominal aortic aneurysm repair. Ann Vasc Surg. 2013 Nov. 27(8):1042-8. [Medline].
Clarençon F, Di Maria F, Cormier E, Gaudric J, Sourour N, Gabrieli J, et al. Comparison of intra-aortic computed tomography angiography to conventional angiography in the presurgical visualization of the Adamkiewicz artery: first results in patients with thoracoabdominal aortic aneurysms. Neuroradiology. 2013 Nov. 55 (11):1379-87. [Medline].
Gloviczki P, Lawrence PF, Forbes TL. Update of the Society for Vascular Surgery abdominal aortic aneurysm guidelines. J Vasc Surg. 2018 Jan. 67 (1):1. [Medline]. [Full Text].
[Guideline] Chaikof EL, Dalman RL, Eskandari MK, Jackson BM, Lee WA, Mansour MA, et al. The Society for Vascular Surgery practice guidelines on the care of patients with an abdominal aortic aneurysm. J Vasc Surg. 2018 Jan. 67 (1):2-77.e2. [Medline]. [Full Text].
[Guideline] Chaikof EL, Brewster DC, Dalman RL, Makaroun MS, Illig KA, Sicard GA, et al. The care of patients with an abdominal aortic aneurysm: the Society for Vascular Surgery practice guidelines. J Vasc Surg. 2009 Oct. 50 (4 Suppl):S2-49. [Medline]. [Full Text].
The UK Small Aneurysm Trial Participants. 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 Nov 21. 352 (9141):1649-55. [Medline].
Lederle FA, Wilson SE, Johnson GR, Reinke DB, Littooy FN, Acher CW, et al. Immediate repair compared with surveillance of small abdominal aortic aneurysms. N Engl J Med. 2002 May 9. 346(19):1437-44. [Medline].
Fillinger MF, Raghavan ML, Marra SP, Cronenwett JL, Kennedy FE. In vivo analysis of mechanical wall stress and abdominal aortic aneurysm rupture risk. J Vasc Surg. 2002 Sep. 36(3):589-97. [Medline]. [Full Text].
Eliason JL, Upchurch GR Jr. Endovascular abdominal aortic aneurysm repair. Circulation. 2008 Apr 1. 117 (13):1738-44. [Medline]. [Full Text].
United Kingdom EVAR Trial Investigators. Greenhalgh RM, Brown LC, Powell JT, Thompson SG, Epstein D, Sculpher MJ. Endovascular versus open repair of abdominal aortic aneurysm. N Engl J Med. 2010 May 20. 362(20):1863-71. [Medline].
Patel R, Sweeting MJ, Powell JT, Greenhalgh RM, EVAR trial investigators. Endovascular versus open repair of abdominal aortic aneurysm in 15-years' follow-up of the UK endovascular aneurysm repair trial 1 (EVAR trial 1): a randomised controlled trial. Lancet. 2016 Nov 12. 388 (10058):2366-2374. [Medline].
Filardo G, Lederle FA, Ballard DJ, et al. Immediate open repair vs surveillance in patients with small abdominal aortic aneurysms: survival differences by aneurysm size. Mayo Clin Proc. 2013 Sep. 88(9):910-9. [Medline].
United Kingdom EVAR Trial Investigators, Greenhalgh RM, Brown LC, Powell JT, Thompson SG, Epstein D. Endovascular repair of aortic aneurysm in patients physically ineligible for open repair. N Engl J Med. 2010 May 20. 362(20):1872-80. [Medline].
De Bruin JL, Baas AF, Buth J, Prinssen M, Verhoeven EL, Cuypers PW, et al. Long-term outcome of open or endovascular repair of abdominal aortic aneurysm. N Engl J Med. 2010 May 20. 362(20):1881-9. [Medline].
O’Riordan M. EVAR Improves Aneurysm-Related Survival Over Surgery. Medscape Medical News. Available at http://www.medscape.com/viewarticle/778123. Accessed: February 6, 2013.
Mehta M, Paty PS, Byrne J, Roddy SP, Taggert JB, Sternbach Y, et al. The impact of hemodynamic status on outcomes of endovascular abdominal aortic aneurysm repair for rupture. J Vasc Surg. 2013 May. 57(5):1255-60. [Medline].
Le Manach Y, Collins GS, Ibanez C, Goarin JP, Coriat P, Gaudric J, et al. Impact of perioperative bleeding on the protective effect of β-blockers during infrarenal aortic reconstruction. Anesthesiology. 2012 Dec. 117 (6):1203-11. [Medline].
Schanzer A, Greenberg RK, Hevelone N, et al. Predictors of abdominal aortic aneurysm sac enlargement after endovascular repair. Circulation. 2011 Jun 21. 123(24):2848-55. [Medline].
Lederle FA, Freischlag JA, Kyriakides TC, Padberg FT Jr, Matsumura JS, et al. Outcomes following endovascular vs open repair of abdominal aortic aneurysm: a randomized trial. JAMA. 2009 Oct 14. 302(14):1535-42. [Medline].
Nishimori M, Low JH, Zheng H, Ballantyne JC. Epidural pain relief versus systemic opioid-based pain relief for abdominal aortic surgery. Cochrane Database Syst Rev. 2012 Jul 11. 7:CD005059. [Medline].
Parodi JC, Palmaz JC, Barone HD. Transfemoral intraluminal graft implantation for abdominal aortic aneurysms. Ann Vasc Surg. 1991 Nov. 5(6):491-9. [Medline].
Reichart M, Geelkerken RH, Huisman AB, van Det RJ, de Smit P, Volker EP. Ruptured abdominal aortic aneurysm: endovascular repair is feasible in 40% of patients. Eur J Vasc Endovasc Surg. 2003 Nov. 26(5):479-86. [Medline].
Tan JW, Yeo KK, Laird JR. Food and Drug Administration-approved endovascular repair devices for abdominal aortic aneurysms: a review. J Vasc Interv Radiol. 2008 Jun. 19(6 Suppl):S9-S17. [Medline].
White GH, Yu W, May J. Endoleak--a proposed new terminology to describe incomplete aneurysm exclusion by an endoluminal graft. J Endovasc Surg. 1996 Feb. 3(1):124-5. [Medline].

Media Gallery

Radiograph shows calcification of abdominal aorta. Left wall is clearly depicted and appears aneurysmal; however, right wall overlies spine.
On radiography, lateral view clearly shows calcification of both walls of abdominal aortic aneurysm, allowing diagnosis to be made with certainty.
CT demonstrates abdominal aortic aneurysm (AAA). Aneurysm was noted during workup for back pain, and CT was ordered after AAA was identified on radiography. No evidence of rupture is seen.
Arteriography demonstrates infrarenal abdominal aortic aneurysm. This arteriogram was obtained in preparation for endovascular repair of aneurysm.
Lateral arteriogram demonstrates infrarenal abdominal aortic aneurysm. Demonstration of superior mesenteric artery, inferior mesenteric artery, and celiac artery on lateral arteriogram is important for complete evaluation of extent of aneurysm.
Arteriogram after successful endovascular repair of abdominal aortic aneurysm.
Ultrasonogram from patient with abdominal aortic aneurysm (AAA). This aneurysm was best visualized on transverse or axial image. Patient underwent conventional AAA repair.
MRI of 77-year-old man with leg pain believed to be secondary to degenerative disk disease. During evaluation, abdominal aortic aneurysm was discovered.
Age is risk factor for development of aneurysm.
Inflammation, thinning of media, and marked loss of elastin.
Pulsatile abdominal mass.
Aneurysm with retroperitoneal fibrosis and adhesion of duodenum.
Aortic endoprosthesis (Cook aortic and aortobi-iliac endograft).
Endoaneurysmorrhaphy
Endovascular grafts.
Atheroemboli from small abdominal aortic aneurysms produce livedo reticularis of feet (ie, blue toe syndrome).
Enhanced spiral CT scans with multiplanar reconstruction and CT angiogram.
Angiography is used to diagnose renal area. In this instance, endoleak represented continued pressurization of sac.

of 18

Table 1. Operative Mortality Risk With Open Repair of Abdominal Aortic Aneurysm

</tbody>

Lowest Risk	Moderate Risk	High Risk
Age <70 y	Age 70-80 y	Age 80 y
Physically active	Active	Inactive, poor stamina
No clinically overt cardiac disease	Stable coronary disease; remote MI; LVEF >35%	Significant coronary disease; recent MI; frequent angina; CHF; LVEF < 25%
No significant comorbidities	Mild COPD	Limiting COPD; dyspnea at rest; O₂ dependency; FEV₁</td></tr>
...	Creatinine 2.0-3.0 mg/dL	...
Normal anatomy	Adverse anatomy or AAA characteristics	Creatinine >3 mg/dL
No adverse AAA characteristics	...	Liver disease (↑PT; albumin </td></tr>
Anticipated operative mortality, 1-3%	Anticipated operative mortality, 3-7%	Anticipated operative mortality, at least 5-10%; each comorbid condition adds ~3-5% mortality risk
AAA = abdominal aortic aneurysm; CHF = chronic heart failure; COPD = chronic obstructive pulmonary disease; FEV₁ = forced expiratory volume in 1 second; LVEF = left ventricular ejection fraction; MI = myocardial infarction; PT = prothrombin time.

Table 2. Abdominal Aortic Aneurysm Size and Estimated Annual Risk of Rupture

AAA Diameter (cm)	Rupture Risk (%/y)
<4	0
4-5	0.5-5
5-6	3-15
6-7	10-20
7-8	20-40
>8	30-50
AAA = abdominal aortic aneurysm.

Table 3. Factors Affecting Risk of Abdominal Aortic Aneurysm Rupture

Factor	Low Risk	Average Risk	High Risk
Diameter	<5 cm	5-6 cm	>6 cm
Expansion	<0.3 cm/y	0.3-0.6 cm/y	>0.6 cm/y
Smoking/COPD	None, mild	Moderate	Severe/steroids
Family history	No relatives	One relative	Numerous relatives
Hypertension	Normal blood pressure	Controlled	Poorly controlled
Shape	Fusiform	Saccular	Very eccentric
Wall stress	Low (35 N/cm²	Medium (40 N/cm²	High (45 N/cm²)
Sex	...	Male	Female
COPD = chronic obstructive pulmonary disease.

Back to List

Author

Saum A Rahimi, MD, FACS Interim Chief, Assistant Professor of Surgery, Division of Vascular Surgery, Rutgers Robert Wood Johnson Medical School

Saum A Rahimi, MD, FACS is a member of the following medical societies: American College of Surgeons, Society for Vascular Surgery, Eastern Vascular Society, Vascular Society of New Jersey

Disclosure: Nothing to disclose.

Chief Editor

Vincent Lopez Rowe, MD Professor of Surgery, Program Director, Vascular Surgery Residency, Department of Surgery, Division of Vascular Surgery, Keck School of Medicine of the University of Southern California

Vincent Lopez Rowe, MD is a member of the following medical societies: American College of Surgeons, American Surgical Association, Pacific Coast Surgical Association, Society for Clinical Vascular Surgery, Society for Vascular Surgery, Western Vascular Society

Disclosure: Nothing to disclose.

Acknowledgements

Suman Annambhotla, MD Fellow in Vascular Surgery, Northwestern University, The Feinberg School of Medicine

Suman Annambhotla, MD is a member of the following medical societies: American College of Surgeons, American Medical Association, Association for Academic Surgery, and Society for Vascular Surgery