LE Extremilty Arterial Angioplasty and Grafts

Question 1

what are some conservative medical treatments for arterial dx (5)? how about some interventional surical treatments? (2)

Answer 1

Conservative/Medical treatment
Cessation of smoking – decrease vasoconstriction
Regular exercise-promote collaterals
Lowering cholesterol and LDL
Medications options: Trental, Pletal – reduce blood viscosity, inhibits platelet aggregtion

Interventional/Surgical treatment
Bypass grafts
Angioplasty and stents

Question 2

what types of bypass are there

Answer 2

Synthetic: PTFE (more common) and Dacron
Organic

Question 3

angioplasty

Answer 3

stent with a balloon to open up the vessel

Question 4

what is this?

Answer 4

ptfe graft

Question 5

what type of aorto-femoal grafts are there? (3)

Answer 5

Question 6

what types of organic bypass grafts are there? (4)

Answer 6

Reversed
In situ
Composite
Great or Lesser saphenous, basilic,cephalic)

Question 7

what type of graft

Uses greater saphenous vein (GSV) in native bed
Valves leaflets are excised
Perforators / tributaries are ligated
Proximal and distal ends are anastomosed to artery

Answer 7

Femoral - distal graft In situ Vein Graft

Question 8

what is this?

Answer 8

Valvulatome - cuts out valves in vessels

Question 9

what type of graft is this

Answer 9

in situ vein graft (rt) due to occluded sfa (lt)

Question 10

what type of graft

Answer 10

In situ
femoro-popliteal
graft

Question 11

what type of graft

Answer 11

In situ fem-tibial graft

Question 12

what type of graft has these procedures?

GSV harvested
Perforating veins and tributaries are ligated and cut
Vein reversed and implanted as bypass
Valves are not excised
Small diameter proximally, large diameter distally is advantageous

Answer 12

Reverse vein graft

Question 13

how often are grafts surveyed after complete?

Answer 13

Evaluation immediately post op
1 week post op
6 week post op
Every 3 months x 2 years
Every 6 months for life

Question 14

a few days after a graft patients experience _______. describe the waveform. how long before this resolves?

Answer 14

Acute Hyperperfusion
1-2 days post op.
Revascularization hyperemia because patient still vasodilated
High peak systolic
High diastolic (low resistance)
Resolves in 2-3 weeks

Question 15

what type of graft failures might you expect w/ a synthetic graft?

Answer 15


1-2 years out = technical error or fibrointimal lesions at anastomosis

2-5 years out = progression of atherosclerotic disease of native vessels proximal or distal to graft with chronic thrombus

5-10 years out = pseudoaneurysms (esp aorto-femoral) secondary to infections

Question 16

what type of graft failure

0-2 months = technical error such as poor anastomosis, AVF from perforators, poorly lysed valves

1-2 years = fibro-intimal lesions at anastomosis or at valves sinuses

>2 years = progression of atherosclerotic disease

Answer 16

autogenous

Question 17

what can slow flow in a graft (failure) be due to?

Answer 17

Decreased inflow:
Arterial disease proximal to graft
Stenosis at proximal anastomosis

Decresed outflow:
Arterial disease distal to graft
Stenosis at distal anastomosis

Stenosis within the graft causing slow flow distal to the stenotic area AVF of the graft decreasing flow distally

Question 18

what % is the stenosis rate within 1 year of a graft?

if graft occludes, ______% patency rate after thrombectomy

_____% of graft stenoses are ASX, due to limited ambulation - limb salvage

Answer 18

20-30 %

20-50

60

Question 19

the following steps are _________

Identify graft type
Perform ABI – if applicable, also could do toe PPG and metatarsal

Map graft and record spectral waveforms
Prox to graft
Prox anastomosis site
Mid graft
Distal anastomosis site
Distal to graft

Measure PSV and EDV
Evaluate waveform morphology – triphasic, high resistance, acceleration, etc.

Answer 19

Bypass graft surveillance

Question 20

what is the avg graft flow velocity?

Answer 20

Question 21

what do you look for when evaluating a graft?

Answer 21

wall irregularity

partially excised valve leaflets

A-V in non-ligated perforators (insitu only)

Aneurysm

P-aneurysm

Question 22

what type of testing can you do over a graft?

a ____ drop in ABI suggests graft stenosis

_______ is more sensitve than ABI for stenosis

Answer 22

PVR, not segmentals

0.15

duplex

Question 23

50% stenosis
Peak Velocities > ______
Velocity ratio > ____
Post stenotic turbulence

>75% stenosis
Peak vel > ___
Velocity ratio >____
Post stenotic turbulence

Distal flow of <____ cm/s associated with high rate of graft failure

Color flow shows _____ and __________

Be aware of increased velocities large vein graft entering smaller artery as with reversed.

Answer 23

Peak Velocities > 150cm/s
Velocity ratio > 2.0

Peak vel > 250 cm/s
Velocity ratio > 3.0

45

aliasing, turbulence

Question 24

what velocity is considered normal in a vein graft?

Answer 24

Question 25

What is the threshold for graft revision?

Answer 25


> 300 cm/s

VR > 3.5

low velocity < 40-45 cm/s

ABI

Question 26

what type of graft stenosis is this?

Answer 26

reverse vein graft stenosis

Question 27

what is this?

Answer 27

vein graft aneurysm

Question 28

what is happening here?

how can you tell?

Answer 28

pseuodoaneurysm

Most commonly at anastomosis site

Perigraft fluid collection with swirling flow

To and Fro

Ying-Yang with color

Question 29

what will the waveforms look like for an AV Fistula in the graft pro and distal and in the ein prox and distal?

 Connection from deep vein to superficial vein graft, via a non-ligated perforator

Answer 29

Graft proximal – low resistance
Graft distal – high resistance, low flow volume

Vein proximal – pulsatile
Vein distal – no change

Question 30

what is the purpose of Percutaneous angioplasty (PTA)?

what types are there?

Answer 30

Access to obstruction via vessel

Palmaz - balloon deployed
Wallstent - self expanding

Dilatation with balloon

Stents: Post PTA. stent helps reduce restenosis

Question 31

what are the peripheral vascular stent sites?

Answer 31

Aorta
renals
iliacs
femoral - popliteal
carotid

Question 32

what is this?

Answer 32

stent deployment