Unit 2 Aneurysms

Question 1

Define arterial aneurysm

Answer 1

Localized dilation of blood vessel that is caused by a congenital or acquired weakness of media (middle layer). Aneurysm = weak BV media

Question 2

Describe the 4 descriptive categories of aneurysms

Answer 2

1) Fusiform aneurysm—ovoid swelling 2) Saccular (aka “berry”) aneurysm—bubble-like swelling 3) Dissecting aneurysm—blood hemorrhages into media separating layers of vascular wall 4) Arteriovenous aneurysm—direct communication between an artery and vein

Question 3

Where do ABDOMINAL aortic aneurysms usually arise?

Answer 3

Abdominal aorta below (distal to) renal arteries and above (proximal to) aortic bifurcation (to common iliacs)

Question 4

Describe the clinical presentation of abdominal aortic aneurysm

Answer 4

Many asymptomatic—discovered on XRAY or PE. Usually pulsatile abdominal mass that grows with time.

Question 5

Major medical complication of abdominal aortic aneurysm and its clinical presentation

Answer 5

Rupture and exsanguination into retroperitoneum (or chest). Patient presents with triad: hypotension, pulsatile abdominal mass, flank pain. Patient often exhibits symptoms of shock.

Question 6

Minor complications of abdominal aortic aneurysm

Answer 6

Compression of local abdominal structures (i.e. ureters) and thrombosis/embolism

Question 7

Describe pathogenesis of abdominal aortic aneurysm

Answer 7

Atherosclerosis/inflammation—> dysregulated wall repair, atrophy of media layer—> increased wall stress—> aneurysm; Note: these are also considered atherosclerotic aneurysms

Question 8

Describe the “classic” patient with abdominal aortic aneurysm

Answer 8

Older male (>60) smoker with hypertension

Question 9

Where do THORACIC aortic aneurysm usually arise?

Answer 9

Usually in ascending aorta

Question 10

THORACIC aortic aneurysm are classically seen which conditions? Describe the gross pathology

Answer 10

Syphilis (aka syphilitic aneurysm or aortitis) due to endarteritis (inflammation) of aortic vaso vasorum—>narrowing, decreased flow and BV wall atrophy; Thoracic aorta is dilated with inner surface “tree bark” appearance.

Question 11

Major complication of THORACIC aortic aneurysm

Answer 11

Dilation of aortic valve root—>aortic valve insufficiency

Question 12

Minor complications of THORACIC aortic aneurysm

Answer 12

Compression of mediastinal structures (airway or esophagus) and thrombosis/embolism

Question 13

Describe the clinical presentation of aortic dissection; correlate to the anatomic pathology

Answer 13

Sharp, tearing chest pain that radiates to the back; Loss of one or more pulses and/or murmur of aortic regurgitation; Pathology: BV intimal tear with dissection of blood through the media of aortic wall (creates a false lumen of BV).

Question 14

Where do AORTIC DISSECTIONS commonly occur

Answer 14

Ascending aorta (proximal 10 cm) and its major branches-coronary, renal, mesenteric, iliac or great vessels; areas preexisting weakness of media

Question 15

What are the most common causes of aortic dissection?

Answer 15

Hypertension; also associated with inherited CT disorders (i.e. Marfan Syndrome, Ehlers-Danlos, Loeys-Dietz Syndromes)

Question 16

Describe the pathogenesis of aortic dissection

Answer 16

Hypertension—>hyaline arteriolosclerosis of vaso vasorum—> decreased flow—> atrophy/weakening of BV media; If inherited, CT disorders cause weakening of BV media predisposing to dissection.

Question 17

3 complications of aortic dissection

Answer 17

1) Pericardial tamponade (MCC of death), 2) rupture with fatal hemorrhage, 3)obstruction of branching arteries—> endo organ ischemia

Question 18

Most common type of cerebral aneurysm

Answer 18

Berry aneurysm (a saccular aneurysm)

Question 19

Where do berry aneurysm commonly occur?

Answer 19

Circle of Willis—branch points or arterial junctions; Between ACA and Anterior Communicating Arteries; Between Internal Carotid and Posterior Communicating Arteries; Between Middle Cerebral Artery and bifurcation of Internal Carotid.

Question 20

Berry aneurysm result from…

Answer 20

Mostly congenital defects of the vessel wall

Question 21

Major complication of berry aneurysm

Answer 21

Subarachnoid hemorrhage

Question 22

Describe Charcot-Bouchard microaneurysm

Answer 22

Small aneurysms of the cerebral vasculature that are associated with chronic hypertension. Usually found in lenticulostriate vessels of basal ganglia. Rupture is common cause of hemorragic stroke