1. Chapter 13 Evaluation of arterial bypass grafts and stents

2. Treatment of Lower Arterial Disease
Conservative treatment
cessation of smoking
regular exercise
lowering cholesterol and LDL
Medications options: Trental, Pletal

3. Interventional Procedures
Bypass graft
Synthetic: Polytetrafluoroethylene (PTFE) , Dacron
Autogenous vein grafts
Reversed
In situ
Percutaneous angioplasty (PTA)
Stents

4. Aorto-femoral grafts 1. 2. 3.
Axillo-fem
Fem-fem
Aorto-iliac
Fem -Fem

5. Femoral - distal graft In situ Vein 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

6. Valvulatome

7. Occluded SFA In situ vein graft CFV CFA PFA SFA GSV CFA GSV ligated
Perforators
Valves
CFV
CFA
PFA
SFA
GSV
CFA
GSV
ligated
perforators

8. Reverse vein graft GSV harvested
CFA
SFA
Vein
graft
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

9. PTFE Graft

10. In situ fem-tibial graft
femoro-popliteal
graft

11. Graft surveillance 20-30 % stenosis rate within 1 year
if graft occludes, 20-50% patency rate after thrombectomy
60% of graft stenoses are ASX, due to limited ambulation - limb salvage

12. Bypass graft surveillance
Identify graft type
Perform ABI
Map graft and record spectral waveforms prox, mid and distally
Measure PSV

13. Graft evaluation Graft inflow and anastomosis entire graft
wall irregularity
partially excised valve leaflets
A-V in non-ligated perforators (insitu only)

14. Graft evaluation Aneurysm P-aneurysm Distal anastomosis run-off
Vein graft aneurysm

15. Distal anastomosis Stenosis has an abrupt increase in velocity
High frequency
Stenosis has an abrupt increase in velocity

16. Bypass graft surveillance
0.15 drop in ABI suggests graft stenosis
Duplex is more sensitive than ABI for stenosis

17. > 50% graft stenosis Peak Velocities > 150cm/s
Velocity ratio > 2.0
Post stenostic turbulence

18. Pt. Flint
Recent In-situ femoro-popliteal.
No increase post-op in ABI

19. Vein graft stenosis

20. Graft - valve stenosis
Graft stenosis

21. Vein graft -pre stenosis
PSV 39 cm/s

22. Vein graft, max stenosis
PSV 504 cm/s

23. Graft- Post stenosis
PSV 120cm/s

24. Distal vein graft
PSV 49 cm/s

25. Graft surveillance
Dennis Bandyk, MD, RVT

26. Graft surveillance Threshold for graft revision > 300 cm/s
VR > 3.5
low velocity < cm/s
ABI
Dennis Bandyk, MD, RVT

27. Reverse vein graft stenosis
Valve cusp
Transverse vein graft

28. Stents
Palmaz - balloon deployed
Wallstent - self expanding

29. Palmaz stent - nonexpanded
Palmaz stent expanded on PTA balloon

30. Stent sites: peripheral vascular
Aorta
renals
iliacs
femoral - popliteal
carotid

31. Stent deployment

32. Carotid stent

33. Graft waveform 1 week post op
Hyperemia will usually occur in normal, patent grafts in the early post op period.

34. Endoluminal AAA repair with covered stent
Fem-fem bypass