Aneurysms and dissections

Question 1

aneurysms are

Answer 1

-Aneurysms are dilatations of the aorta due

to weakening of the wall

Question 2

dissections are

Answer 2

-Dissections (also called dissecting aneurysms)
lead to widening of the vessel as the result
of blood dissecting through the wall of the
vessel

Question 3

aneurysms most commonly occur

Answer 3

in the abdominal aorta distal to the renal arteries

Question 4

causes of aneurysms

Answer 4

1. atherosclerotic weakening of the wall of the aorta
   2.also occur as a result of infection, vasculitis, or structural abnormalities
   -syphilis: aneurysms of the ascending (thoracic) aorta
   -genetic abnormalities of collagen, elastin: ascending
   aorta

Question 5

how do dissections occur?

Answer 5

as a result of blood passing through a tear in the intima
-dissections split the vascular media and create a false
vascular channel

Question 6

dissections most commonly occur in

Answer 6

thoracic aorta

Question 7

dissections are most commonly associated with?

Answer 7

hypertension

Question 8

death from dissections are caused by?

Answer 8

hemopericardium and cardiac tamponade

Question 9

what is a true aneurysm?

Answer 9

bounded by generally complete but attenuated arterial wall components

Question 10

what is a false aneurysm?

Answer 10

• (pseudoaneurysm) – widening due to extravascular hematoma that communicates with the lumen (dissection)

Question 11

atherosclerosis as a cause of aneurysms

Answer 11

-usually positioned below the renal arteries and above the
bifurcation of the aorta
-often associated with dilatations of the iliac arteries
-may affect origins of the renal, superior, and inferior
mesenteric arteries
-thinning and destruction of media resulting from
ulceration of atherosclerotic areas
-cylindrical aneurysms which may rupture
-increased diameter increases risk; 50% mortality
-risk of rupture for small aneurysm 2%
-develop after 50; much more common in men
-familial (other than atherosclerosis or
hypertension)

Question 12

consequences of abdominal aneurysms

Answer 12

-rupture - peritoneal cavity or retroperitoneal
tissues
-impingement on an adjacent structure
-occlusion of a vessel be either direct pressure or
mural thrombus
-vertebral branches that supply the spinal cord
-embolism from the atheroma or mural thrombus
-abdominal mass that simulates a tumor

Question 13

berry aneurysms

Answer 13

congenital weakness of arterial wall (usually CNS)
-outpoouching
-usually sporadic
-sometimes associated with autosomal dominant
(adult form) polycystic kidney disease
-also associated with Ehlers-Danlos syndrome
-most common around circle of Willis
-anterior communicating artery(40%)>middle
cerebral artery (34%)>junction of
carotid/posterior communicating artery (20%)
-bifurcations of cerebral arteries

Question 14

vasculitic aneurysms

Answer 14

-Kawasaki, Wegener’s, temporal arteritis, Takayasu’s etc

Question 15

mycotic aneurysms

Answer 15

Salmonella gastoenteritis

Question 16

thoracic aorta aneurysms

Answer 16

• syphilitic
• genetic tissue disorders – Marfan’s, Ehlers-Danlos, etc.
• bicuspid aortic valve

Question 17

what is the most common rupture in young adults?

Answer 17

berry aneurysms

• causes subarachnoid hemorrhage
• occurs with acute increases in arterial pressure, as will weight lifting

Question 18

those with berry aneurysms present with

Answer 18

• acute, severe headache
• transient loss of consciousness
• associated with reactive cerebral vasospasm

Question 19

consequences of a thoracic aneurysm

Answer 19

-encroachment on mediastinal structures
-respiratory difficulties
-difficulty in swallowing/compression of esophagus
-persistent cough due to irritation of or pressure on the
recurrent laryngeal nerves
-incompetence of aortic valve at aortic root
-rupture of the aneurysm – hemopericardium with
cardiac tamponade

Question 20

dissections leads to what kind of aneurysm

Answer 20

false aneurysm
-actually a misnomer; most dissections occur without
significant aneurysm

Question 21

how are the locations of dissections different from aneurysms?

Answer 21

usually affects ascending and proximal aorta with
intimal tear within 10 cm of aortic valve
-associated with hypertension; Marfans, Ehlers-Danlos
-tears are usually transverse or oblique, 1-5 cm long
-produces false channel

Question 22

where do dissecting intramural hematomas form?

Answer 22

-characteristically between middle and outer

thirds of the media

Question 23

what is the most common cause of death with dissections?

Answer 23

death is rupture into body cavity (pericardial, pleural, peritoneal)
*hemopericardium is most common cause of death

Question 24

what are the common manifestations in dissections?

Answer 24

-cardiac tamponade, aortic insufficiency, myocardial infarction

Question 25

classic symptoms of dissections

Answer 25

-include sudden onset of excruciation pain, usually beginning in the anterior chest, radiating to the back, and moving downwards as the dissection progresses; often confused with acute myocardial infarction

Question 26

what do complications depend on with dissections?

Answer 26

level of aorta affected -proximal lesions more common (and dangerous) -second type include distal lesions (usually beginning distal to subclavian artery)

Question 27

Cystic medial necrosis

Answer 27

-non-specific term for several etiologies

Question 28

characteristic changes with cystic medial necrosis

Answer 28

-elastic tissue fragmentation and disruption -focal separation of elastic and fibromuscular elements -small cleft-like or cystic spaces WITH AMORPHOUS MATERIAL; INFLAMMATION IS ABSENT -characteristic of Marfan’s and other collagen diseases -may be associated with fusiform aneurysms or aortic dissection

Question 29

why is cystic medial necrosis an inaccurate name?

Answer 29

necrosis is not present

Question 30

Marfan's

Answer 30

-autosomal dominant disease of connective tissue fibrillin -skeletal, cardiovascular, and ocular manifestations -dilatation and dissection of aortic root; mitral valve prolapse

Question 31

Ehler’s-Danlos Syndrome

Answer 31

- Heterogeneous group of collagen disorders | - Several subtypes: joint, skin, and vascular phenotypes

Question 32

extreme phenotypes of Ehler's-Danlos syndrome

Answer 32

-include “circus” freaks demonstrating joint hypermobility and stretching of skin * most patients do not demonstrate such extreme phenotypes; many are missed because doctor’s are looking for freaks

Question 33

symptoms of Ehler's-Danlos syndrome

Answer 33

- involve joints, skin, large blood vessels - frequent dislocations, joint injuries - easy bruising, delayed wound healing - scoliosis, near-sightedness, gum disorders

Question 34

what causes death in E-D syndrome

Answer 34

- vascular aneurysms (berry aneurysm, thoracic aneurysms), uterine, bladder, or intestinal rupture - treatment of hypertension essential - anticipation of complications (childbirth)

Question 35

Syphilis (Luetic aneurysms)

Answer 35

-associated with tertiary syphilis -nearly always confined to thoracic aorta; usually involving the arch *may involve aortic root with aortic valve insufficiency *occlusion or narrowing of coronary ostia

Question 36

Cor Bovinum

Answer 36

greatly enlarged heart secondary to aortic valve insufficiency

Question 37

pathophysiology in Luetic aneurysms

Answer 37

-inflammation of adventitia; obliterative endarteritis of the vasa vasorum with infiltrate of lymphocytes and plasma cells -secondary ischemic injury of aortic media with patchy loss of medial elastic fibers and muscle cells; inflammatory scarring of the media -associated with both aneurysmal dilatation and dissection -treebarking of the aortic intima results from segmental wrinkling due to scar contraction

Question 38

Arteriovenous fistulas

Answer 38

anomalous connection between artery and vein -may be congenital or secondary to trauma, inflammation, etc. -can cause significant left to right shunts, overloading the right side of the heart and causing right heart failure -can also rupture and cause significant bleeding (cerebral aneurysm) -presents as stroke (younger population)

Question 39

What are the signs of a ruptured berry aneurysm

Answer 39

Headache Subarachnoid hemorrhage Blood in CSF

Question 40

Berry aneurysms are seen with

Answer 40

Marfans Ehlers danlos Polycystic kidney disease (autosomal recessive in Kids, dominant in adults)

Question 41

Berry aneurysms most commonly occur in

Answer 41

Around circle of Willis Anterior communicating artery> middle cerebral artery>junction of carotid/ posterior communicating artery Bifurcations of cerebral arteries