Pathology of the Aorta (Part 2)

A Pseudoaneurysm (false) aneurysm is a

pulsatile mass (hematoma)

Pseudoaneurysm​ occur at

a puncture site, trauma, surgical anastomosis site, or infection

How does a Pseudoaneurysm differ from a true aneurysm

it doesn’t involve all three layers of the vessel

What is happening with the blood in a Pseudoaneurysm​?

it is leaking into soft tissue through a hole in the innermost vessel lining

What is anastomosis?

a surgical procedure that creates a connection between two tubular structures, such as blood vessels, intestines, or airways

Blood circulation of a Pseudoaneurysm​ during systole

inward

Blood circulation of a Pseudoaneurysm​ during diastole

turbulent flow outward

This image is showing

Flow of a Pseudoaneurysm​

This image is showing

color flow of a Pseudoaneurysm​

Pseudoaneurysm​ treatment:

• compression of mass with transducer

• 20 min intervals X until gone or clotted off

• monitor with color doppler to confirm communication is closed

• may require surgical intervention

Idiopathic AAA

• True AAA – lined by all 3 layers of aortic vessel​

• Develop infrarenal (> 85% of pts.)​

• Extend to bifurcation

• no clear cause

Dissection is a

tear in vessel wall

Complications of idiopathic AAA

• Rupture​

• Thrombosis​

• Dissection​

• Distal embolism​

• Infection​

• Obstruction​

• Invasion of adjacent structures​

• Branch artery occlusion or stenosis

Aneurysm may be described as

fusiform or saccular

fusiform aneurysm is the

most common type of aneurysm

fusiform aneurysm is a

atherosclerotic aneurysm

You will find a fusiform aneurysm

• inf aorta near bif

• gradual transition between normal and abormal

• extends over length of aorta (Football shape)

• extend into iliacs

When looking at a fusiform aneurysm on US you can find

atherosclerosis of vessel, decreased pulsations of walls, bright echoes = thickening & calcification​

Saccular aneurysm is also knows as:

Bulbous

What is a saccular aneurysm

• Sharp, sudden transition between normal & abnormal​

• Spherical & larger than fusiform​

• Connected to vascular lumen by a mouth​

• Follow path of AAA to:​

• R/O retroperitoneal mass or lymphadenopathy​

• Diminished pulsations due to clot formation

Saccular aneurysm is connected to the vascular lumen by

mouth

This image is showing a

saccular aneurysm

Large AAA may

compress or displace surrounding structure

mycotic aneurysms are

infected aneurysms (aorta)

How will a AAA compress or displace surrounding structures

• CBD = obstruction​

• RA = HTN, ischemia​

• Ureter obstruction

Inflammatory Aortic Aneurysm​ / Mycotic Aneurysm is a

rare condition development of a mycotic (infected) AAA

Normal Iliac artery measures

< or equal to 2 cm (Needs to be measured in 2 planes)

IAA =

vessel diameter > 2cm or 1.5 X normal size

IAA measurement for surgical repair

> 3 cm

Protocol of IAA

• Measure AP/length/ Width of IAA

• Measure AP/Width of lumen

• Assess clot or thrombus formation

• Document Color and Pulse Doppler

Classic Symptoms of RUPTURED AAA

• Excruciating abdominal pain​

• Shock​

• Expanding abdominal mass​

• Most common site of rupture: lateral wall inferior to RA​

• Extravasation (hemorrhage)

IAA rupture into

retrosigmoid colon, iliac vein or ureter​

Need to document where the AAA is compared to renals because

it affects the kind of stent they put in

Clottication:

pain in arms and legs because there is not enough blood flow

Syphilis

STI that can cause inflammation in the aorta potentially causing an aneurysm

Cystic medial necrosis is a type of

marfans disease. The tunica medias collagen fibers in the aorta are breaking down increasing the risk of aneurysms

Grey Turner’s Syndrome

when aneurysm ruptures they will have bruising at flanks bc blood is pooling at abdomen