1. Aortic Aneurysms
Mark A. Farber, MD

2. Aortic Aneurysms Incidence
30-60/1000
Increasing incidence over past 3 decades
Incidence of AAA
Autopsy %
U/S Screening %
Pts with CAD %
Pts with PVD %
Pts with femoral and pop.aneurysms 50.0%

3. Aortic Aneurysms Definition
Pseudoaneurysm
True Aneurysm

4. Definitions
Aneurysm - Increase in diameter of 50% (1.5x) its normal diameter – Focal region
Ectasia - Diffuse dilatation of an artery with increase in diameter >50%
Arteriomegaly - Diffuse enlargement of an artery, but not lg. Enough to meet criteria for an aneurysm

5. Aortic Aneurysms Associated Aneurysms
Iliac - 41%
Femoro-popliteal - 15%
Pts with unilateral popliteal aneurysms-->8% AAA
Pts with bilateral popliteal aneurysms--> 30%-50% AAA

6. Aortic Aneurysms Associated Medical Conditions
Carotid Artery Stenosis - 10% have AAA
Smoker:Nonsmoker - 8:1
Male:Female - 4:1
HTN - 40% of pts with AAA have HTN

7. Aortic Aneurysms Etiology
Atherosclerosis
Cystic Medial Necrosis
Dissection
Ehlers-Danlos Syndrome
Syphilis
Familial Associated
Lysyl Oxidase deficiency

8. Aortic Aneurysms Etiology
Decrease in elastin and collagen in arterial wall
Elastin becomes fragmented-->arterial elongation and dilatation
Increase in the collagenase and elastase activity

9. Aortic Aneurysms Etiology
Multifactorial

10. Aortic Aneurysms Physics
Laplace’s Law
T = P x R
T - Tension
P - Pressure
R - Radius

11. Aortic Aneurysms Clinical Presentation
Asymptomatic %
Symptoms:
Early satiety, N,V
Abd., Flank, or Back pain
1/3 of pts experience abd. And flank pain
Abrupt onset of pain -->Rupture or expansion of aneurysm

12. Aortic Aneurysms Ruptured Aneurysms
Small tear-> pain, followed by frank rupture
Usually occurs postero-laterally
Can rupture in Vena Cava creating Aorto-Caval Fistula
Occasionally can rupture anterior - usually fatal

13. Ruptured Aneurysm Thumbnail Sketch
60-70 y/o who presents with c/o abd pain, hypotension and a pulsatile abdominal mass

14. Aortic Aneurysms Diagnosis
Physical Exam:
If <5cm in diameter, then cannot be detected by routine physical exam
Radiographs:
Calcified wall. Can determine size in 2/3
Cannot rule out and AAA

15. Aortic Aneurysms Diagnosis
Arteriography:
Cannot determine aneurysm size because of mural thrombus
Indications for obtaining arteriography
Suspicion of visceral ischemia
Occlusive disease of iliac and femoral arteries
Severe HTN, or impair renal function
? Horseshoe Kidney
Suprarenal of TAAA component
Femoro-Popliteal Aneurysms

16. Aortic Aneurysms Diagnosis
Ultrasound
Establishes diagnosis easily
Accurately measures infrarenal diameter
Difficult to visualize thoracic or suprarenal aneurysms
Difficult to establish relationship to renal arteries
Technician dependent
Widely available, quick, no risk, cheap

17. Aortic Aneurysms CT Scan
Very reliable and reproducible
Can image entire aorta
Can visualize relation ship to visceral vessels
Longer to obtain and is more costly than U/S
Most useful
Requires contrast agent - renal toxicity

18. Aortic Aneurysms MRA Now widely available More expensive than CT
No contrast agent required
Spacial resolution less than CT

19. Aortic Aneurysms Risks
Complications of AAA
Thrombosis
Distal embolization
Rupture
23.4% of aneurysms 4-5 cm will rupture

20. Aortic Aneurysms Rupture Risks
Patients with COPD and HTN have increased risk of rupture
Rate of enlargement:
0.5 cm/ year
Survival
50% die prior to reaching hospital, and an additional 24% prior to repair.

21. Aortic Aneurysms Treatment Risks
Mortality
% with current surgical techniques
Morbidity
5-10% usually associated with cardiac events
Endovascular Techniques are significantly reducing morbidity and mortality associated with repair

22. Aortic Aneurysms Indications for Treatment
Presence of an infrarenal aneurysm > 5cm without associated co-morbid medical conditions
Repair smaller aneurysms if rate of enlargement is greater than expected
Repair all symptomatic aneurysms
If co-morbid conditions exist wait until risk of repair and rupture are equal (approx. 6 cm)

23. Aortic Aneurysms Treatment-Surgical
Standard Surgical Repair
Replace diseased aorta with artificial artery
Requires 7 day hospital stay
Recovery time 3-6 months
Proven method with good long term results

24. Aortic Aneurysms Treatment - Endovascular
Repair through an incision in the groin with expandable prosthesis under fluoroscopic guidance
Requires both surgical and radiological assistance
Significantly reduced m+m
Long tern result unknown
Hospital stay 2 days, Recovery time 1-2 weeks