Ir -- Aorta And Ivc

Front 1

1. What are the anatomical issues that must be addressed prior to stent graft placement for AAA?

Back 1

1. Iliac arteries must be of suitable caliber (7-8mm) to premit introduction of stent-graft delivery apparatus.
2. Proximal and distal necks of the aneurysm should be of sufficient length (>15mm)
3. Necks should be free of significant angulation or plaque which may interfere with proper device seating.
4. Distance from the origin of the lowest renal artery to the internal iliac artery origins must be measured in order to select the proper device length.

Front 2

1. Why is it important to embolize the internal iliac artery when placing a stent graft for AAA that extends into the common iliac artery?
2. What are some complications of internal iliac artery embolization?

Back 2

1. There is a potential for endoleak via cross pelvic collaterals from the contralateral internal iliac artery.
2. If the contralateral internal iliac artery and IMA are diseased, colonic ischemia and buttock claudication may develop.

Front 3

1. What are the findings of chronic IVC occlusion?
2. What are some causes of IVC occlusion?
3. Is there a role of thrombolysis?
4. What is post thrombotic syndrome?

Back 3

1. Occlusion of the IVC typically occurs below the level of the renal veins. The LE are drained by a prominent lumbar venous plexus which drains into the azygous and hemiazygous venous systems.
2. Occlusoin of the IVC may be from
- extension of iliofemoral DVT
- IVC filter placement
- compression by a pelvic mass.
3. Thrombolysis may be effective for acute thrombosis. Pts are at risk of post-thrombotic syndrome and some may benefit from thrombolysis with or without stent placement.
4. Post thrombotic syndrome is a result of valvular damage leading to chronic venous insufficiency and ulceration.

Front 4

1. What are some causes of abdominal aortic occlusion?
2. What is Leriche's syndrome?
3. What are some clinical features of Leriche's syndrome?
4. What is the treatment of distal abdominal aortic occlusion? What is a potential complication of the procedure?

Back 4

1. Atherosclerosis, thromboembolism, trauma, dissection, Takayasu arteritis.
2. Thrombosis of the abdominal aorta superimposed on chronic atherosclerotic stenosis.
3. Absent femoral pulses, hip and buttock claudication, impotence.
4. Aortobifemoral bypass. Pseudoaneurysm formation at the proximal or distal anastomosis.

Front 5

What are the collateral anterior, middle, and posterior pathways for abdominal aortic occlusion?

Back 5

Anterior route: aortic arch --> internal mammary and intercostal arteries --> inferior epigastric artery --> common femoral arteries.

Middle route: SMA --> Middle colic artery --> Enlarged artery of Drummond and arc of Riolan --> IMA --> superior hemorrhoidal --> middle and inferior hemorrhoidal --> internal iliac arteries --> external iliac arteries

Posterior route: Subcostal and lumbar arteries --> deep circumflex iliac arteries --> femoral arteries.

Front 6

1. What is considered a megacava?
2. What are appropriate size measurements for insertion of bird's nest filter?
3. At what size do you need to place bilateral common iliac vein filters?

Back 6

1. Megacava is defined at IVC diameter > 28 mm.
2. Bird's nest filter is placed for IVC diameter 28-40mm.
3. If IVC is greater than 40mm in diameter, then bilateral common iliac filters should be placed.

Front 7

What is the DDX of absence of inflow from the left common iliac vein on cavography?

Back 7

1. Caval duplication
2. Left pelvic DVT
3. May-Thurner syndrome

Front 8

What are the indications for IVC filter placement?

Back 8

1. Contraindication to anticoagulation therapy:
2. Failure of anticoagulation therapy.
3. Complication of anticoagulation therapy: bleeding or thrombocytopenia.
4. Free floating iliac vein and/or IVC thrombus.

Front 9

1. What are the findings of impending aortic rupture or early aortic rupture/leak?
2. What are the features of coagulopathic hemorrhage?

Back 9

1. "Crescent" and "draped" aorta are signs associated with impending or early rupture of an aortic aneurysm.
Bleeding from a ruptured AAA is contiguous with aneurysm. Look for a focal eccentric bulge and associated disruption of intimal calcification.
Bleeding usually starts in the retroperitoneum but may extend into the peritoneal cavity.
2. Coagulopathic hemorrhage usually occurs in patients receiving heparin or Coumadin. The bleeding usually starts in the iliopsoas compartment and then spreads into the retroperitoneum. Look for the hematocrit sign, which is both sensitive and specific for a coagulopathic hemorrhage.

Front 10

What are some specific considerations for thoracic aortic stent graft placement?

Back 10

1. Degree of thoracic aortic curvature
2. Relationship of aneurysm to the left subclavian aftery - if 2 cm proximal neck is not present, then the subclavian artery must be surgically ligated.
3. Location of key intercostal arteries. It is wise to minimize coverage of patent intercostal arteries.

Front 11

1. How do pts with aortic or common iliac artery stenosis present?
2. What are the treatment options for aortoiliac atherosclerotic disease?
3. What kind of stents are placed for aortoiliac junction atherosclerotic disease?

Back 11

1. If atherosclerotic disease is limited to the distal aorta and common iliac arteries, the patients present with hip and buttock claudication and/or impotence due to limitation of flow into the internal iliac artery territories.
2. Surgical aortofemoral bypass or endovascular treatment (angioplasty +/- stent placement).
3. Patients with aortoiliac junction lesions with or without aortic stenosis are treated with kissing stents regardless of whether the contralateral iliac artery is diseased. It minimizes risk of emboli and contralateral plaque shift.

Front 12

1. Why is left iliofemoral DVT more common than right?
2. What is May-Thurner syndrome?
3. How is May-Thurner syndrome treated?
4. What is post-thrombotic syndrome?

Back 12

1. There is relative compression of the left iliac vein by the right common iliac artery at the pelvic brim.
2. May-Thurner syndrome describes this external compression of the left iliac vein by the right common iliac artery. It is differentiated from bland thrombus in the iliofemoral system by noting an external compression upon the left iliac vein.
3. Catheter directed thrombolyis followed by iliac vein stent placement.
4. Post-thrombotic syndrome represents the major long term complication of DVT secondary to venous valvular incompetency. It is characterized by LE edema, venous statis, ulceration, discoloration, pain, varicosities, and venous claudication.

Front 13

1. At what size do you treat iliac artery aneurysms?

Back 13

1. 3-4 cm.

Front 14

1. What are the causes of aortoenteric fistula?
2. What are the imaging findings of aortoenteric fistula?

Back 14

1. Causes of aortoenteric fistula can be divided into primary (uncommon) or secondary (post open/surgical AAA repair).
- Primary aortoenteric fistula occurs when an aortic aneurysm ruptures into the bowel.
- Secondary aortoenteric fistula occurs after open repair of AAA. It can occur at the level of the aorta-graft anastomoses involving the suture line or 2/2 breakdown of the bowel wall overlying a graft leading to contamination of the graft by enteric contents.
2.
- Perigraft soft tissue with loss of fat plane between the aorta and small bowel loop
- Focal bowel wall thickening
- Gas collection in the wall or adjacent to the aorta

Front 15

1. What is the classification of endoleaks?
2. Why are delayed images important for follow up of aneurysms?
3. How are type 2 endoleaks managed?

Back 15

TYPE 1: Attachment site leak
Poor seal of the graft and native vessel allows blood to flow around graft into aneurysm.
TYPE 2: Side branch perfusion
The aneurysm sac is filled retrogradely by arteries originating from the aneurysm sac such as IMA and lumbar arteries.
TYPE 3: Structural failure
Separation of modular components or breakdown of the graft leads to perfusion of aneurysm.
TYPE 4: Graft porosity
Blood flows through covered portion of stent graft. Self limited and resolves quickly.
2. Delayed scans are needed to detect some type 2 leaks that slowly perfuse the sac.
3. Type 2 endoleaks may either be treated immediately or observed and treated only with aneurysm expansion. A translumbar approach is used (CT guided needle puncture of the aneursym sac) followed by embolization of the branch vessels.

Front 16

What are the treatment options for pts with type B dissection who present with visceral or peripheral arterial ischemia?

Back 16

1. Aortic stent placement
2. Balloon fenestration of intima.

Front 17

1. Name the different IVC filters.
2. What are common errors during IVC filter placement?
3. What do you look for in the cavagram?

Back 17

1.
- Simon-Nitinol filter: looks like 2 umbrellas.
- Bird's nest filter: accomodates IVC diameter upto 40mm.
2.
- IVC filter deployment error (upside down IVC filter): remember that there are different filters for different approaches.
- IVC filter deployment into lumbar or paraspinal vein 2/2 inadvertent catheterization of lumbar vein overlying IVC. Looks like the filter does not open up. Rx: insert second filter.
3.
- Diameter of the IVC
- Level of the lowest renal vein
- Inflow from the left common iliac vein
- Free floating thrombus.
4. Ideal filter placement is infrarenal with apex of the filter at the level of the renal veins.

Front 18

Thoracic aortic aneurysm

Back 18

- higher incidence of rupture than AAA
- Growth rate of thoracic aneurysms is greater than the growth rate of AAA
- Aneurysms of the aortic arch have hte fastest expansion rate.
- Surgical intervention is considered when the aneurysm size exceeds 5.5 cm for the ascending aorta and 6.5 cm for the descending aorta.

Front 19

Penetrating atherosclerotic ulcer

Back 19

usually confined to the intima and are commonly asymptomatic.
when the ulcer penetrates deeper into the aortic wall, intramural hematoma formation is present.
- Can progress to a dissection, pseudoaneurysm, or rupture.

Front 20

Aortic dissection

Back 20

HTN
TRAUMA
CONNECTIVE TISSUE DISEASE:
- Ehlers-Danlos syndrome affects the aortic media resulting in arterial fragility.
- Aneurysms, vascular rupture or dissection are common.
ANNULOAORTIC ECTASIA:
- AKA cystic medial necrosis
- degeneration of connective tissue of the aortic media results in cystic medial necrosis, leading to dilation of the ascending aorta and aortic annulus with aortic insuffiiciency.
- Can be seen with Marfan's syndrome
BICUSPID AORTIC VALVE
- pts are at higher risk of aortic aneurysms and dissections.
COARCTATION OF AORTA:

Front 21

What are the angiographic findings of Takayasu's arteritis?

Back 21

- Large vessel vasculitis that leads to smooth concentric narrowing of the aorta and main branches.
- Most commonly, the left subclavian artery is involved, followed by right subclavian artery.
- Most common presentations = neurological sx, h/o stroke, asymmetric arm blood pressure measurements.

Front 22

Long term IVC Filter
complications

Back 22

- Filter migration (spontaneous, iatrogenic by wire)
- Breakthrough PE (2.6-3.8%)
- IVC perforation
- IVC thrombus or occlusion (3.6-11.2%)

Front 23

Indications for Suprarenal placement of IVC filter

Back 23

1. Renal vein thrombosis
2. IVC thrombosis with no room below renal veins
3.Š Filter placement during pregnancy or in women of childbearing age
4. Thrombus extending above previously placed filter
5. PE after gonadal vein thrombosis
6. Anatomic variants: duplicated IVC, low insertion of renal veins

Front 24

1. What are the indications for temporary filter placement?
2. Which temporary filters are used at your institution?

Back 24

1. Temporary filters are indicated when anticoagulation is temporarily contraindicated.
- DVT in late pregnancy.
- Patients with DVT or PE requiring surgery.
- Patients at high risk for PE/DVT about to undergo surgery
- While performing lytic therapy for DVT.
2. Celect, G2