Chapter 70 - Aortoiliac aneurysms - evaluation, decision and medical management Flashcards
Egypt 1550BC on aneurysms
First described
Galen on aneurysms
First anatomical description
Antyllus on aneurysm
attempted ligation
Versalius in 14th century on aneurysms
Cadaveric dissections to fully describe anatomy
Pare/Morgagni 14th century on aneurysms
associated it with syphilis
Cooper 1817 and Matas 1888 on aneurysms
Described ligation and obliteration of aneurysms
Pappe 1946 on aneurysms
Wrapping the aneurysm
Carnel/Dubost 1950’s on aneurysms
Autologous reconstruction
Vorhees 1952, Debakey and cooley on aneurysms
synthetic reconstruction
Parodi 1990 on aneurysms
first EVAR
When did FDA approve EVAR
1999
Aneurysm Dissection and Management (ADAM) Veterans Affair Cooperative Study Groupstated this
Variations in age, sex, race, BMI/BSA not enough to deviate from standard of AAA definition and indications for repair
How much of aortic aneurysms are infrarenal
30%
Incidence of aneurysms > 4cm in men 55-64 and rate of increase
1% in 55-64 men 2-4% increase every 10 years
Risk factors for aneurysm formation
1) Smoking (proportional to duration) 2) Family history 3) Atherosclerosis 4) MI 5) PAD 6) HTN
Factors associated with less aneurysms
1) smoking cessation duration 2) female 3) African 4) diabetes
Rate of adjacent aneurysms with AAA
juxta/suprarenal 5-15% iliac 10-25% thoracic 12% fem/pop 14%
Popliteal aneurysms prevalence in general population
1%
Rate of finding AAA when there are aneurysms in other locations
Popliteal 62% Femoral 85% CIA/IIA 86%
Most common iliac artery in iliac aneurysms
CIA
Rate of isolated CIA aneurysm
6.4%
Rate of IIAA with AAA
2%
Causes of IIAA
1) degenerative 2) trauma 3) Vasculitis (Behcet, FMD, Takayasu, Connective tissue) 4) mycotic (rare)
Mayo Clinic Group on CIAA
1) growth 0.29 cm/yr 2) no ruptures seen < 3.8 cm 3) average asymptomatic 5.1 cm; symptomatic 7.6cm, rupture 8.3cm
Rupture risk of AAA as per UK small aneurysm trial
2.2% most in 5-5.5 cm
Risk factors for rupture of AAA (patient factors)
1) female 2) size 3) smk 4) decreased FEV1 5) increased MAP No association with 1) age 2) BMI 3) cholesterol 4) ABI
Risk of rupture at different sizes
3-3.9 cm = 0.3%/yr 4-4.9 cm = 0.5-1.5%/yr 5-5.9 cm = 1-11%/yr 6-6.9 cm = 11-22%/yr >7 cm = >30%/yr
Risk factors for rupture of AAA (aneurysm factors)
1) saccular 2) mural thrombus 3) dissection 4) disruption of peripheral calcification
Rate of growth that warrants repair
> 1cm in 12 months
Thoracic Aorta vs abdominal aorta in embryological histology
1) Thoracic media from neura crest cells; abdominal media from mesoderm 2) thoracic media has 55-60 lamellar units for vasa vasorum to penetrate; abdominal only has 28-32
Intraluminal thrombus (ILT) mechanism of thinning walls
Plasmin (MMP) and TGF beta cause degradation and thins wall; loss of SMC; elastin degradation and adventitia inflammation
Problem with using U/S in assessing AAA
fail to identify ruptures in 50% of the time
Screening recommendations by different societies
ESVS 2010 and NSC (UK) 2007: men > 65 SVS 2009: men > 65 and 1st degree relative; men 60-85 and female 60-85 with FMHX CSVS 2007: men 65-75, men < 65 with FMHX; female > 65 with smk, CVD, FMHX American college of cardiology/AHA: men > 65; female 65-85 with FMHX; every 6-12 months to detect expansion
Medical management that showed promise in animals to reduce aneurysm growth or reduce rupture risk
1) Statin 2) ACEi 3) beta blocker 4) tetracycline 5) doxycycline 6) antiplatelets none work in humans
Vascular study group of new england (VSGNE) risk index uses
CEA Bypass EVAR OAAA
VSGNE OAAA factors
1) creatinine 2) distal anastamosis location 3) BMI 4) proximal clamp location 5) race 6) CAD 7) COPD 8) recent stress test 9) CHF 10) age
Connective Tissue Syndromes Associated With Abdominal Aortic Aneurysms
