Chapter 9: Abdominal Vasculature Flashcards
What is abdominal aortic aneurysm?
enlargement of the diameter of the abdominal aorta to greater than 3 cm
What is atherosclerosis?
a disease characterized by the accumulation of plaque within the walls of the arteries
What is an embolism?
a blockage caused by an abnormal mas within the blood stream that hinders circulation downstream, leading to tissue damage
What is a false aneurysm?
a contained rupture of a blood vessel that is most likely secondary to the disruption of one or more layers of that vessel’s wall
What is false lumen?
the residual channel of a vessel created by the accumulation of a clot within the vessel
What is fusiform?
shaped like a spindle; wider in the middle and tapering towards the ends
What is high-resistance flow?
the flow pattern that results from small arteries or arterioles that are contracted, which produces an increase in the resistance to blood flow to the structure that is being supplied
What is an intimal flap?
observation of the intimal layer of a vessel as a result of a dissection
What is low-resistance flow?
the flow pattern characterized by persistent forward flow throughout the cardiac cycle
What is Marfan syndrome?
a disorder of the CT characterized by tall stature and aortic and mitral valve insuffiency
What are mycotic aneurysms?
aneurysms caused by infection
What does postprandial mean?
after a meal
Psuedoaneurysm AKA
false aneurysm
What is a saccular aneurysm?
a saclike dilation of a blood vessel
What is small bowel ischemia?
a condition resulting in interruption or reduction of the blood supply to the small intestines
What is a thrombus?
a blood clot
What is TCC?
a malignant tumor of the urinary tract that is often found within the urinary bladder or within the renal pelvis
What is a true aneurysm?
the enlargement of a vessel that involves all three layers of the lumen
What is true lumen?
the true channel within the vessel
What is tunica adventitia?
the outer wall layer of a vessel
What is tunica intima?
the inner wall layer of the vessel
What is tunica media?
the middle, muscular layer of the vessel
What is Wilms tumor?
the most common solid malignant pediatric abdominal mass; or renal mass AKA nephroblastoma
The aorta originates where?
the left ventricle
Most abdominal arteries are considered to have _____ -________ flow
low resistance flow
Where on the abdominal aorta does the celiac trunk arise from?
anterior aspect, between the crura of the diaphragm
What are the three branches of the celiac trunk?
- splenic art
- left gastric art
- common hepatic art
Describe the flow pattern of the suprarenal aorta
low-resistance flow
Describe the flow pattern of the infrarenal aorta
high-resistance flow
Does the celiac artery have low or high resistance flow?
low-resistance
Does the common hepatic artery have low or high resistance flow?
low-resistance
Does the common iliac artery have low or high resistance flow?
high-resistance flow
Does the splenic art have low or high resistance flow?
low-resistance
The SMA of a fasting patient has what kind of flow?
high-resistance
The SMA of a postprandial patient has what kind of flow?
low-resistance
Renal arteries have what kind of flow?
low-resistance
Is the splenic artery tortuous or straight?
tortuous
The common hepatic artery branches into the ______ at the level of the pancreatic head
gastroduodenal artery
When does the common hepatic art become the proper hepatic art?
after the pancreatic head
Where does the proper hepatic artery enter the liver?
porta hepatis
The cystic artery comes off what branch of the hepatic arteries?
right hepatic artery, and supplies the GB
The SMA supplies blood to what?
- small intestines
- some of colon
- pancreas
The SMA can be ID’d sonographically by what?
the echogenic fat layer surrounding it
If wave forms look backwards in the SMA, what is suspected?
small bowel ischemia
The third main visceral branches of the aorta are what?
paired renal arteries
Describe location of right renal artery?
originates from the right anterolateral aspect of the aorta and travels posterior to the IVC on its way to the right renal hilum
Describe the location of the left renal artery ?
originates from the left anterolateral aspect of the aorta and travels posterior to the left renal vein as it progresses to the left renal hilum
Which renal artery is longer?
right
T/F: duplication of the renal arteries is common?
true
What are the fourth branches of the abd. aorta?
gonadal arteries..either testicular or ovarian
The IMA arises from where?
the anterior surface of the abd aorta
The IMA supplies what?
- transverse colon
- descending colon
- rectum
The aorta will gradually become more _____ as it travels away from the diaphragm
anterior
The upper normal limit of the abdominal aorta just below the diaphragm is ___ cm
2.5 cm
The aorta in the mid abd. should measure ____cm or less
2cm
The distal aorta diameter should measure ____cm
1.8 cm or less
The common iliac arteries are considered enlarged if their diameter exceeds ___ cm
2 cm
Describe the normal flow pattern for the infrarenal aorta
triphasic, high resistance flow pattern with reversal of flow during early diastole
An aneurysm results from
weakening of the vessel wall
Most AAA’s are what?
true aneurysms
The most common shape of an AAA is
fusiform
Saccular can be described as
sudden dilation of artery, often spherical and can be fairly large
The most common location of an AAA
infrarenal
What is the most common cause of aneurysms in the US?
atherosclerosis
Aneurysms of the AA have been associated with
- atherosclerosis
- Marfan syndrome
- syphilis
- familial inheritance
- infection
Aneurysms caused by infection are called
mycotic aneurysms
Complications of AAA include
- distal embolism
- infection
- dissection
- rupture
Clinical findings of AAA
- pulsatile abd. mass
- bruit
- back pain
- abd. pain
- lower extremity pain
Son findings of AAA
- diameter of AA measures greater than 3 cm
- thrombus within the lumen of aorta
- calcifications, along with thrombus, may produce acoustic shadowing
List the clinical findings of aortic dissection:
- intense chest pain
- htn
- abdominal pain
- lower back pain
- neurologic symptoms
What size AAA is more prone to rupture?
7cm or greater
Clinical findings of AAA rupture:
- decreased hematocrit
- hypotension
- pulsatile abd. mass
- abdominal bruit
- back pain
- abdominal pain
- lower extremity pain
Psuedo/false aneurysms may be associated with what?
- interventional procedures
- surgery
- trauma
- infection
Where is a common site for pseudoaneurysm development after a heart cathaterization?
the groin at the level of the femoral art
The IVC is created by the union of what?
common iliac veins
Where does the IVC terminate?
right atrium
What are the four sections of the IVC from superior to inferior?
- hepatic
- prerenal
- renal
- postrenal
The most superior portion of the IVC courses
posterior to the caudate lobe of the liver and through the bare area
Variants of the hepatic veins include
- duplication
- branching anomalies
Describe waveform of hepatic veins
pulsatile, triphasic blood flow pattern
Which renal vein is longer?
left
Renal veins have what kind of flow?
low velocity, continuous
The right gonadal vein drains into what?
IVC
The left gonadal vein drains into what?
left renal vein (much longer than right gonadal vein)
The diameter of the IVC should never exceed
2.5cm
The main portal vein is created by the union of what vessels?
SMV and splenic vein..creating the portal splenic confluence
The portal splenic confluence collects blood from where?
intestines and spleen
Where does the main portal vein enter the liver?
porta hepatis
Should flow in the portal veins be mono or biphasic?
monophasic
Typically the diameter of the portal vein is less than
13 mm
Flow in the splenic vein should be toward:
midline
Do tumors more often affect the right or left renal veins?
right
What is the most common cause of IVC obstruction that leads to enlargement?
right sided heart failure
The abnormal connection between arteries and veins is
arteriovenous fistulas
Arteriovenous malformations may be caused by
- congenital
- surgery
- malignancy
- biopsy
- trauma
What may be seen in cases of AVM’s?
turbulent flow and focal accumulation of vascular structures
In small bowel ischemia, the postprandial SMA will yield what flow pattern?
high resistance
Which vascular structure may be confused for the main pancreatic duct?
splenic artery
Which of the following is the shortest in length? A. right renal vein B. right renal artery C. left renal vein D. left renal artery
A. right renal vein
