3. General Considerations
• The term aneurysm describes dilatation of any blood
vessel.
• Most prevalent in the infrarenal aorta (abdominal
aortic aneurysm[AAA]).
• In the United States, AAA were directly responsible for
approximately 9900 deaths in 2014, and approximately
120,000 AAA procedures were performed to prevent
subsequent rupture.
• These lesions may be the result of several degenerative
processes, includinginflammatory, infectious, genetic,
and traumatic conditions.
4. • Multiple complications most dreaded is rupture.
• The risk of rupture -absolute size of the aneurysm
and relative to the normal diameter of the inflow
and outflow artery from which it arises.
• A variety of other factors, including location,
etiology, growth rate,
• Aneurysm morphology (i.e., fusiform vs.
saccular)
5. Historical Perspective
• Egyptian mummies -3500 years ago.
• The Ebers Papyrus (c.2000 BC: “Treat it with a knife and
burn it with a fire so that it bleeds not too much.”
• Antyllus
• John Hunter 1785 -collateral -superficial femoral artery
to treat a popliteal aneurysm.
• Rudolph Matas- 1923
• Bigger
• Charles Dubost in 1951
• DeBakey-polyester
• Juan Parodi
6.
7.
8. ANEURYSM DEFINITION
“A permanent localized (i.e., focal) dilatation of an artery having at least a
50% increase in diameter compared with the expected normal diameter
of the artery in question”
• Aortic
11. True Versus False Aneurysms
TRUE
• Dilatation of the entire wall
FALSE
• Locally contained
hematoma from disruption
of vessel wall
• Has a neck and cavity
• Therapy directed at its
thrombosis.
• loss of anastomotic integrity
at the site of a prior surgical
anastomosis.
12.
13. Location and Extent
• Ectasia refers to an intermediate stage of enlargement,
when an artery is abnormally large, but less than 50%
greater than normal,
• Arteriomegaly refers to diffuse, continuous enlargement of
multiple arterial segments, dilated to greater than 50% of
normal.
(Both arterial ectasia and arteriomegaly are associated with
an increased risk for aneurysm disease in first-degree
relatives Of affected patients )
• Aneurysmosis is often used to describe multiple aneurysms
in several anatomic locations, or the combination of
aneurysmal degeneration in the setting of arteriomegaly.
14. Morphology
FUSIFORM
• Generalized increase in the
entire diameter of the
affected vessel
• True degenerative
aneurysms are more likely
to have a fusiform
configuration.
SACCULAR
• Localized and often
eccentric in shape
• eccentric defects arising
from a focal ulcer or
weakness in the arterial
wall
• Due to trauma or infection
• pseudoaneurysms
15.
16. Etiology
• Degenerative
• The terms degenerative and atherosclerotic are often used
to describe the most common type of aneurysms.
• The relationship of atherosclerosis to aneurysm formation
is complex, but both aneurysms and obstructive
manifestations are often found in the same patient cohort,
with either the aneurysmal or obstructive manifestation
predominating.
• Metalloproteinases in the media of aneurysm specimens.
• Deficit of antiproteolytic -tissue inhibitor of
metalloproteinase 1.
• The intensity and duration of cigarette smoking
17. Inflammatory
• The term inflammatory refers to an aneurysm
with an exaggerated inflammatory
component, which often incites a fibrotic
reaction around the aneurysm.
• The infrarenal abdominal aorta is most often
affected by this inflammatory process
• Rind around the exterior of the affected
vessel, which may or may not envelope
adjacent structures.
18. • Inflammatory infrarenal -ureteral obstruction
• Genetic susceptibility have shown similarities between
degenerative versus inflammatory aneurysms.
• Detailed studies of the cellular infiltrate and cytokine
profiles are warranted.
• Difficulty of dissecting surrounding-duodenal perforation
and ureteral injury.
• Endovascular repair -regression of the peri-aneurysmal
inflammation and fibrosis.
• Takayasu arteritis, giant cell arteritis, polyarteritis nodosa,
Behçet disease, Cogan syndrome, and cystic medial
necrosis represent
19. • The primary surgical challenge associated with these lesions is the
difficulty of dissecting surrounding structures safely during the
open repair of these lesions.
• The complications associated with traditional open surgery -
duodenal perforation and ureteral injury.
• Endovascular repair of inflammatory aneurysms has been reported
to result in regression of the peri-aneurysmal inflammation and
fibrosis.
• Takayasu arteritis, giant cell arteritis, polyarteritis nodosa, Behçet
disease, Cogan syndrome, and cystic medial necrosis .
• The location and severity of these aneurysms are related to the
specific diagnosis and the ability to control the primary process with
medical therapy .
20.
21. Aneurysms Associated With Arterial
Dissection
• Spontaneous arterial dissection in the aorta, also occur in
peripheral arterial locations.
• Arterial dissection describes a spontaneous tear of the intima of an
artery and the subsequent propagation of that tear along the
anatomic plane within the media .
• The failure of the initial intimal tear to propagate may result in a
penetrating aortic ulcer or intramural hematoma.
• Arterial pressure and acute arterial distention as the result of mural
delamination are the driving forces behind the propagation of the
dissection.
• Common clinical symptomatic presentation of this process is
thoracic aortic dissection in either the ascending or descending
portion, or both.
22. • The structural integrity of arteries is dependent on the
integrity of their composite (three-layer) structure.
• Occlusive symptoms and subsequent aneurysmal
degeneration.
• Aneurysmal degeneration resulting from dissection can
take the form of acute distention and rupture, or a less
severe acute dilatation followed by progressive
dilatation over time.
• Chronic aneurysms due to dissection are generally
treated by the same guidelines for size, growth, and
symptoms that are used for the management of
degenerative aneurysms.
23. Traumatic
• Aneurysms that result from trauma are
pseudoaneurysms, perforation of an artery
that results in local containment of
hemorrhage rather than uncontrolled
bleeding.
• The location of these aneurysms parallels the
location and incidence of trauma.
24. Developmental and Congenital
Anomalies
• Embryologic defect -primary arterial or cardiac
anomaly.
• Persistent sciatic artery
• Kommerell diverticulum is another form of
aneurysmal
• Congenital AAAs -tuberous sclerosis
• Aortic aneurysm increases in incidence
• from 5% in the general population to
approximately 20% to 30% in male siblings of an
aneurysm patient.
25.
26. Infectious
• Hematogenous seeding
• Adjacent infectious process
• Bacteria
• fungi (e.g., Candida, Aspergillus),
• tuberculosis, and syphilis have
• Incidence is increased in patients with a history of illicit drug
injection/abuse and in patient populations that are severely
immunosuppressed .
• Surgical repair utilizing antibiotic impregnated prosthetics,
cryopreserved allografts, and primary endovascular stent-grafting in
these cases remains controversial
27.
28. Specific Arteries
• Aortic
• Ascending aorta are degenerative/ sequela prior
aortic dissection;
• Aortic arch and descending aorta - aneurysmal
disease.
• Infrarenal location - AAAs are at least nine times
more common than thoracic aneurysms
• thoracoabdominal aneurysms, are less frequent
than either isolated
• thoracic or isolated AAA
29. Iliac
• Most common in the Common iliac
• Only11% presented without a concomitant aortic
aneurysm
• Internal iliac aneurysms -next most common
• rupture in 40% of patients and are associated
with a 31% mortality rate
• External iliac aneurysms are rare- associated with
traumatic lesions or other nondegenerative
causes.
30. Femoral
• True aneurysms of the femoral artery is low, likely
on the order of 5/10,000 patients.
• Complications occur if > 3.5 cm or contain
thrombus.
• Frequently bilateral (26%)
• 88% of patients have a synchronous aneurysm at
another site.
• Pseudoaneurysms result as a complication of
percutaneous femoral access or disruption of
prior surgical bypass anastomoses.
31.
32. Popliteal
• Most common peripheral arterial aneurysm.
• Approximately 1% of men aged 65 to 80 years.
• Popliteal aneurysms are frequently bilateral and
often occur concomitantly with aortic aneurysms.
• workup of any patient with an AAA.
• Primary morbidity associated with popliteal
aneurysms is acute thrombosis or embolization
with resulting limb ischemia and potential limb
loss, rather than rupture and hemorrhage.
33. Visceral
• Occur in approximately 1% of the population, based on
postmortem series.
• Splenic artery aneurysms- second most common aneurysmal lesion
in the abdominal cavity, and account for approximately 60% of all
visceral or splanchnic aneurysms.
• More frequently in women and are also associated with portal
hypertension.
• Pregnancy is a specific risk factor for rupture.
• Many visceral aneurysms can be managed with endovascular
techniques including endografting or embolization.
• aneurysms involving the hilum, laparoscopic splenectomy can also
• be performed.
34. Renal
• The renal circulatory bed is characterized by its low resistance and
high flow characteristics, and this profuse flow is an explanation for
the location and frequency of renal aneurysms.
• Often saccular rather than fusiform, most often with fibromuscular
dysplasia.
• connective tissue disorders, arteritides, trauma, and spontaneous
dissection
• Sequelae of renal artery aneurysms include thrombotic and embolic
events, poorly controlled hypertension, and rupture.
• Risk of rupture in the third trimester of pregnancy, with resulting
maternal and fetal mortality rates of 70% and 100%
35. Current recommendations for repair include
• size greater than 2 to 3 cm,
• lesions occurring in women of child-bearing age,
• refractory hypertension,
• flank pain,
• hematuria.
• The size criteria for intervention are not based on
rigorous data, and this may represent too aggressive an
approach in some patient populations.
• Both endovascular and open surgical reconstruction
36. Cerebrovascular
• Whereas intracranial aneurysms are relatively
common
• extracranial cerebral arteries are rarely affected
by aneurysmal degeneration.
• The few aneurysms that do occur in the carotid
are in the internal, common, and external
segments in order of decreasing frequency.
• Dissection, which may occur after trauma, can
lead to late aneurysmal degeneration in both the
internal carotid and vertebral artery
37. Upper Extremity
• Subclavian artery aneurysms can result from
the repetitive trauma associated with thoracic
outlet syndrome.
• Iatrogenic brachial pseudoaneurysms as a
consequence of percutaneous arterial access
38. Multiple Aneurysms
• Aortic
• 50% of patients with thoracic aneurysms also had
abdominal aneurysms and that 12% of patients with
abdominal aneurysms had thoracic .
• Patients with connective tissue disorders or other
systemic conditions that predispose to aneurysmal
degeneration obviously have a significantly higher
prevalence of multiple aneurysms and recurrent
aneurysm disease.
• These patients must be monitored closely throughout
their lives for the development of aneurysms in both
typical and atypical locations.
39.
40. Peripheral
• Popliteal aneurysm is the most frequently
occurring peripheral aneurysm and is the most
common aneurysm to be bilateral;
• Synchronous and metachronous aneurysms in
other sites are also common.
• 59% of the patients had bilateral aneurysms
and 49% had coexisting AAAs.
• aneurysms can occur in multiple locations, but
their prevalence is far lesser.
41. Familial
• Patients with a family history of aneurysm
disease have a 30% increased risk of having an
aneurysm, although the specific genetic
explanation for this susceptibility has not been
elucidated.
• This is true for AAAs discovered outside the
context of a diagnosed congenital disorder or
connective tissue disorder.
42. Connective Tissue Disorders
• Connective tissue disorders are primary causes of familial
aneurysmal disease and require careful genetic characterization and
counseling.
• Ehlers-Danlos, Marfan, and Loeys- Dietz syndromes, and a variety of
less common connective tissue defects (see Chapter 140).
Cystic Medial Degeneration
• A familial pattern of thoracic aortic aneurysm has been termed
familial thoracic aortic aneurysm syndrome
• Presence of a bicuspid aortic valve has been associated with a high
incidence of ascending aortic aneurysm, and cystic medial
degeneration has been proved by tissue biopsy in 75% of these
patients.
• Turner syndrome is also associated with ascending aortic
aneurysm, aortic dissection, and bicuspid aortic valve.
