1. Abdominal Aortic Aneurysms Diagnosis and treatment

2. AAA defintion Varies by age, gender, body surface area
Typically diagnosed if aortic diameter is ≥ 3.0 cm*
Normal aorta
Aorta with an abdominal aneurysm
*ACC/AHA Guidelines on PAD Circulation 2006;113:e

3. ACC/AHA Guidelines on PAD Circulation 2006;113:e463-465.
Prevalence of AAA
In the US, AAA causes almost deaths each year and accounts for hospital discharges
Age (years)
Men
Women cm
45-54
1.3% 0%
75-84
12.5%
5.2%
ACC/AHA Guidelines on PAD Circulation 2006;113:e

4. Risk factors associated with AAA
Older age
Male sex
Family hx
Smoking
Hypertension
Dyslipidemia
Atherosclerotic disease
COPD
ACC/AHA Guidelines on PAD Circulation 2006;113:e

5. Types of AAA Morphological classification Segments involved
fusiform aneurysms
saccular aneurysms
dissecting aneurysms
pseudo-aneurysms
Segments involved
thoracic
thoraco-abdominal
abdominal
main branches of the aorta
iliac arteries
Aneurysm Classification
Fusiform aneurysm is a cylindrical and symmetrical dilatation that involves the entire circumference of the aortic wall.And is more common than saccular.
Saccular aneurysm is more a localized outpouching of only a portion of the aortic wall.
Dissecting aneurysm is a hemorrhagic separation of the medial layer of the vessel wall which creates a false lumen.
Pseudo or false aneurysm is a well defined collection of blood and connective tissues outside the vessel wall. This may be a consequence of a contained aortic wall rupture from trauma or anastomotic disruption.
Aortic aneurysms can also be classified according to the segment involved, thoracic, thoracoabdominal and abdominal (may occur in the branches of the aorta as well. The clinical presentation and treatment depend greatly on their location 5

6. AAA Sequelae Natural history Complications
gradual and/or sporadic expansion
accumulation of mural thrombus
Complications
rupture
thromboembolic events
compression of adjacent structures

7. Pathological changes cause the aorta wall to
Progression of a AAA
Pathological changes cause the aorta wall to
become thinner
bulge
tear
rupture

8. Mean growth rate (cm/yr)
Growth rate of AAA
Initial size (cm)
Mean growth rate (cm/yr)
95% CI
0.39
0.36
0.43
0.64
Tan W Abdominal Aortic Aneurysm Rupture

9. Symptoms of AAA rupture
Abdominal/back pain
Pulsatile abdominal mass
Hypotension
Clinical triad occurs in only about one-third of cases.
ACC/AHA Guidelines on PAD Circulation 2006;113:e

10. AAA: risk of rupture
Risk of rupture for untreated aneurysm within 5 years (%)
75% 80 70 60 50 40
35%
25% 30 20 10
A review of six case-series including 703 cases of ruptured aneurysm estimated that only 18% of all patients with ruptured AAA reached a hospital and survived surgery. (See Ref 25)
5-5.9cm
6-6.9cm
≥7cm
Aneurysm size
Simplifed estimates based on various studies
Tan W Abdominal Aortic Aneurysm Rupture 10

11. Rupture outcomes Mortality rate can be as high as 80%[1]
More than one third of rupture cases die outside the hospital[2]
Ruptured AAA
Adam. J Vasc Surg 1999;30:922-8.
Thomas. Br J Surg Aug 1988

12. Operative mortality 35-70% for ruptured aneurysm
Pae. J Am Surg 2007; Qureshi. Ann Vasc Surg 2007; Greco. J Vasc Surg 2006; Pepplenbosch. J Vasc Surg 2006; Visser. Eur J Vasc Endovasc Surg 2005; Brown. Br J Surg 2002; Heller. J Vasc Surg 2000; Adam. J Vasc Surg 1999; Johansen. J Vasc Surg 1991; Ouriel. J Vasc Surg 1990.
% for elective AAA cases
Qureshi. Ann Vasc Surg 2007; Cowan. Ann NY Acad Sci 2006; Heller. J Vasc Surg 2000; Bradbury. Br J Surg 1998; Blankensteijn. Br J Surg 1998.

13. ACC/AHA screening high-risk
Men ≥ 60 yrs who are siblings or offspring of AAA patients
Men yrs who have ever smoked
Physical exam and ultrasound
Class I
Class IIa
Class IIb
Class III
ACC/AHA Guidelines on PAD Circulation 2006;113:e

14. Diagnosis: physical exam
In one study (N=198)
48% of AAA cases were diagnosed clinically
physical exam missed 38% of cases detected radiologically
Karkos CD. Eur J Vasc Endovasc Surg 2000;19:

15. Sensitivity of physical exam
Aneurysm diameter
Sensitivity cm
29% cm
50%
≥ 5.0 cm
76%
Pooled analysis of 15 studies
Lederle. JAMA 1999;281:77-82.

16. Sensitivity of ultrasound
Ranges from 82% to 99%
Approx 100% in cases with a pulsatile mass
In a small proportion of patients, visualization of the aorta inadequate due to obesity, bowel gas, or periaortic disease
Quill. Surg Clin North Am 1989;69:

17. Ultrasound screening
P=0.003
P=0.001
P=0.002
Controlled screening trial of men age 65 to 73 ITT analysis n=6333 screened, n=6306 control
Lindholdt. BMJ 2005;330:750. 17

18. ACC/AHA Guidelines AAA repair
Infrarenal/juxtarenal AAA ≥5.5 cm should undergo repair; cm, ultrasound/CT scans every 6-12 mo
Repair can be beneficial for infrarenal/juxtarenal AAAs cm
Repair probably indicated for suprarenal/type IV thoracoabdominal AA > cm
AAA <4.0cm, ultrasound every 2-3 years is reasonable
Intervention not recommended asymptomatic infrarenal/ juxtarenal AAAs <5.0 cm (men) or <4.5 cm (women)
Class I
Class IIa
Class IIb
Class III
ACC/AHA Guidelines on PAD Circulation 2006;113:e

19. Endovascular stent grafting
Treatment options
Endovascular stent grafting
Open surgery

20. Open repair: advantages
Established procedure more than 40 years of clinical experience
Excludes aneurysm and prevents sac growth
Proven, long-term results

21. Open surgical repair (OSR): drawbacks
Significant incision in the abdomen
30–90 minute cross-clamp
Up to 4-hour procedure
1–2 days intensive care 7–14 days hospitalization 4–6 weeks recovery time
Open Surgical Repair of AAA
Contraindicated in many patients, usually due to advanced age and associated medical problems. The surgery requires a significant incision in the patient’s abdomen. Full-length (xiphoid to pubis) midline incision provides access to the entire abdominal cavity, including the supraceliac aorta and iliac arteries.
The aorta is cross clamped for a period of minutes. The aneurysm is opened and cleaned of any thrombus and debris. A prosthetic graft of polyester or PTFE is then selected based on the size of the aneurysm and sewn to the aorta, below the renal arteries and above the distal aortoiliac arteries. The wall of the aorta is wrapped and sewn around the graft to protect it. The incision site is then closed with sutures and staples.
Surgical repair can take up to four hours to perform. The patient is typically admitted to the intensive care unit for one to two days post-operatively, in addition to seven to 14 days of routine hospitalization. Total recovery time is four to six weeks.
Open surgical repair has a reported mortality rate of 2 to 5 %. Complications which include bleeding, bowel ischemia, infection, cardiopulmonary morbidity, and wound problems have been reported as high as 20 %. Emergent surgical treatment for ruptured aneurysm is much more costly, and mortality rates have been reported to vary from %, with an average mortality rate of approximately 50 %.
See Ref 35-36 21

22. Contraindications to OSR
High anesthesia risk
Severely obese
Significant cardiac co-morbidities
Previous abdominal surgery/hostile abdomen
Difficult recovery for patient:
risks functional impairment [1]
risk of erectile dysfunction [2]
1. Williamson. J Vasc Surg 2001;33:
2. Lee. Ann Vasc Surg 2000;14:13-19.

23. Early OSR vs watchful waiting
Combined ADAM and UKSAT trials of early/immediate OSR vs surveillance/delayed OSR for AAA < 5.5 cm
N = 2226
Endpoint
Relative risk
95% CI
All cause mortality
1.01
Aneurysm-related mortality
0.78
Lederle. Ann Intern Med 2007;146:

24. Endovascular aneurysm repair (EVAR)
Benefits
minimally invasive
reduced risk of perioperative death
faster recovery

25. AAA repair with stent graft
Postoperative angiogram
Preoperative angiogram 25

26. EVAR Drawbacks Complications and re-interventions intrasac endoleaks
stent graft migration
modular dislocation

27. Endovascular stent grafting
Morphology suitable for endovascular repair
adequate vascular access
appropriate aortic neck length and angulation 27

28. EVAR vs OSR 30-day outcomes
Trial
Endpoint
EVAR
OPEN P
EVAR [1] N=1082 ≥ 5.5 cm
Mortality
1.7 %
4.7 %
0.009
Secondary interventions
9.8 %
5.8 %
0.02
DREAM [2] N=345
≥ 5.0 cm
1.2 %
4.6 %
0.1
Mortality & severe complications
1. Lancet 2004;364: N Engl J Med 2004;351:

29. EVAR vs OSR 2-year outcomes DREAM
Endpoint
EVAR
OPEN P
Survival
89.7%
89.6%
0.86
Survival free of moderate-severe complications
65.6%
65.9%
0.88
Aneurysm-related death
2.1%
5.7%
0.05
N Engl J Med 2005;352:

30. DREAM: sexual dysfunction*
Both EVAR and open repair have a negative impact on sexual function in the early postoperative period.
After EVAR, recovery to preoperative levels is faster than after open repair.
At 3 months, sexual dysfunction levels are similar in both groups.
*Measured 5 aspects (interest, pleasure, engagement, orgasm, erection)
N=153
Prinssen. J EndovascTher 2004;11:

31. Erectile dysfunction
Erectile function worsened after open repair (p=0.002)
Orgasmic function deteriorated after open repair (p=0.001)
Endovascular repair was not accompanied by decreased erectile or orgasmic function (p=0.057 and p=0.068, respectively)
Impairment not associated with age, diabetes, or number of patent hypogastric arteries after repair
Significant association between impaired erectile function and open aneurysm repair (p=0.036)
N=90
Xenos. Ann Vasc Surg 2003;17:

32. Agency for Healthcare Research & Quality review of EVAR vs open surgical repair
Lower perioperative morbidity and mortality
Persistent reduction in AAA-defined mortality to 4 years
No improvement in long-term overall survival or health status
For AAA ≥ 5.5 cm
AHRQ Publication No. 06-E017 August 2006

33. Medicare cohort 4 yr outcomes
Endpoint*
EVAR
OPEN P
Periop mortality
1.2 %
4.8 %
<0.001
AAA rupture
1.8 %
0.5 %
AAA reintervention
9.0%
1.7%
Laparotomy-related
Reintervention
4.1%
9.7%
Hospitalization
8.1%
14.2%
* All 4 yr except perioperative mortality
N= matched patients
Schmermerhorn N Engl J Med 2008;358:

34. Ongoing studies EVAR vs OSR
France
Anévrisme de l’aorte abdominale: chirurgie versus endoprothèse (ACE) ClinicalTrials.gov identifier: NCT US
Open versus endovascular repair (OVER) trial for AAA
ClinicalTrials.gov identifier: NCT