Abdominal Aorta waveform(s)
Low resistance proximal, Higher resistance beyond renals
Celiac Artery supplies
Liver, spleen, stomach, & proximal
... [Show More] small bowel
Branches of the Abdominal AO
1st major-Celiac artery (trunk/axis)
2nd major-SMA
Renals
3rd major-IMA (after renals)
Celiac Axis
Branches into Common Hepatic (to right), Splenic, & Left Gastric (off left)
Common Hepatic Arteries
Gives rise to the Gastroduodenal artery in PANC head & divides into Rt & Lt Hepatics
Splenic Artery
Branches left and posteriosuperior to PANC body/tail
SMA/IMA waveforms
High resistance preprandial/Low resistance postprandial
SMA supplies
Bowel from duodenum to prox small bowel
IMA supplies
Bowel descending & rectosigmoid colon
Right Renal Artery
Branches anterolateral, posterior to IVC
Left Renal Artery
Branches posterolateral
Renal Artery waveform
Low resistance
Portal vein is usually formed by the confluence of
SMV & Splenic veins
*It also receives blood from the inferior mesenteric, gastric, and cystic veins
Portals walls/waveforma
echogenic walls & phasic waveforms
Renal veins are formed by
renal tributaries
Left Renal Vein
Longer than Rt.; Receives suprarenal/Gonadal vein
Left Renal pathway
Anterior to AO; Posterior to SMA
Right Renal Vein
No tributaries; shorter
Hepatic Veins
Hepatofugal flow; from liver to IVC
Patient status for Abdominal Vascular Imaging
NPO 8-12 hours
Ectasia
Local diameter increase with small bulge
(20% increase for Ao <3cm)
AAA growth rate
1-2mm/year until 3-4cm; 5 mm/yr >4cm
Aneurysm classification
2-3cm; 3-4cm for AAA
AAA Intervention
5.5cm (high risk for rupture-catastrophic)
Fusiform
Concentric enlargement; All 3 layers intact
Saccular
Eccentric enlargement; All 3 layers compromised; Less common (<1%); Usually in Thoracic Ao
Types of Saccular AAA
1-Cannula Placement
2-Mycotic aneurysm (bacterial infection Ao wall)
3-Vasculitis (Inflammatory process)
4-Penetrating ulcer rupture into media
Vasculitis/Aortitis
Inflammatory process in wall of Ao beginning with outer (adventitia) layer and moving inward; ie: Takayasu's
Dissection
Intimal wall compromised resulting in 2 lumens
false>true; flow reversal
Type 1 (a/b) endoleak
Leak in anastamosis of graft at (a) prox or (b) distal end
Type 2 endoleak
Aorta branch vessel; exhibits retrograde flow; more dangerous b/c internally bleeding
Type 3/4 endoleak
(3) Junction of modular components; (4) Trans graft flow-graft defect
Chronic Mesenteric Ischemia
"Fear of Food" 95% of Bowel Ischemia cases
Atherosclerotic stenosis/occlusion in main mesenteric arteries: >70% stenosis in 2/3 of principle mesenteric arteries
Ischemia diagnosis criteria via Moneta
Celiac >200cm/s
SMA >275cm/s
Median Arcuate Ligament Syndrome (MALS)
Arch impedes on Celiac during EXPIRATION (non-compressed during inhalation)
Measurement(s) of Splenic Vein
7-17 cm long; 5-10mm diameter
Portal vein diameter
<13mm
Blood supply to liver
75% from Portal VEIN; 25% from Hepatic ARTERY
Portal vein carries ____________ to the liver
Nutrients
Hepatic artery carries ______________ to the liver
Oxygen
Portal Hypertension
Extrahepatic, Hyperdynamic, Intrahepatic (more common)
Extrahepatic Portal HTN
Prehepatic (Portal/splenic vein thrombus, Extrinsic compression of Potral vein)
Posthepatic (IVC/Hepatic vein obstruction)
Hyperdynamic Portal HTN
AV malformation causing arterial portal fistulas
Intrahepatic (within liver)
Presinusodial (less common)
Postsinusoidial (more common)
Cirrhosis/Venoclusive disease
Small liver, large spleen, ascites
LaPlace's law
Larger vessel radius, larger wall tension to compensate for extra pressure
Hydrostatic pressure
Gravitational
Large vessels serve as
Pressure reservoirs
Vasodilation
Stretch to absorb
Vasoconstriction
shrink/squeeze
Energy and stenosis
Prox- PE↑, KE↓(highest total energy)
Within-PE↓, KE↑ (lower TE, Bernouille's)
Distal-PE↑, KE↓ (lowest total energy [Show Less]