Chapter 109 - Infrainguinal disease surgical treatment Flashcards
Risk of severe clinical deterioration of a claudicant in 3-5 years
20%
Risk of major amputation in claudicant in 3-5 years
5%
European consensus document definition of CLI
1) persistent recurrent ischemic rest pain requiring opioid x 2 weeks 2) ankle pressure < 50 3) toe pressure < 30 4) ulceration or gangrene of foot/toes 5) absent pedal pulse in diabetic
Wolfe and Wyatt on subcritical and critical CLI definition
Subcritical: rest pain Ankle pressure > 40 (27% limb alive at 1 year without surgery) Critical: rest pain/tissue loss ankle < 40 (5% limb alive at 1 year)
Perioperative MI for LE arterial reconstruction
2-6.5%
Venous conduit cutoff
2-3 mm - must dilate well 3 mm minimum
Significant lesion based on pressure gradient
10 mmHg OR 15% drop after papaverine
When should GSV bypass not be used as a patch simultaneously
1) thickened arterial wall 2) small donor artery 3) small vein conduit
Linton’s technique
Vein patch first then bypass proximal anast on top of the patch
Isolated popliteal target definition
1) 5 cm long popliteal 2) only geniculate collaterals
Patency of isolated popliteal bypass target at 5 years
50% primary 74% secondary patency
Bypass outflow principle in patient with tissue loss
inline flow with pulsatile foot
When to choose pedal bypass over proximal peroneal
1) adequate conduit 2) frank tissue loss
vein crossing over the proximal PFA
Lateral femoral circumflex vein
Lateral approach to PFA key steps
1) incision in upper thigh lateral to sartorius 2) sartorius and SFA retracted medially 3) raphe between adductor longus and vastus medialis incised to expose PFA
Branches of the profunda femoris artery
medial and lateral circumflex femoral artery 1st, 2nd, 3rd perforating branches
Chance of needing contralateral GSV in future operation
20-25% no merit in saving unless already symptomatic
Miller cuff
prosthetic to a circumferential cuff of vein
Taylor patch
Patching open the hood with vein to make it bigger and more elastic
St. Mary’s boot
the end of one end of the vein patch sews onto the side of another to create a cuff
patency of heparin-bound dacron vs PTFE for above knee bypass at 3 year
55% vs 42% dacron better
below knee bypass with PTFE +/- vein cuff 2 year patency
52% vs 29% vein patch/cuff works
Human umbilical vein for bypass
Thicker and cumbersome to handle and risk of aneurysmal degeneration
Distal AV fistula to increase bypass flow velocity
no clear evidence
Heparin bonded PTFE pharmacodynamic
biologically active heparin up to 12 weeks effect in animals benefit up to 180 days not clear in humans
Carmeda bioactive surface (CBAS)
heparin bonded material
Solution to dilate venous conduit
1000 Units heparin and 60 mg of papaverine in 50-60 ml of autologous blood (better preserve graft endothelium) use saline instead for arm vein because thinner and harder to see leaks otherwise
Types of valvulotomes
Mills - radial cutting Hall and LeMaitre - fixed diameter circumferential blades
Completion assessment of the bypass
1) distal pulse palpation and Doppler flow +/- manual graft compression 2) completion arteriography 3) intraoperative duplex +/- papaverine 4) angioscope
Post-bypass arteriography chance of correcting
8-27% patency increase from 72% to 100% in two weeks
Completion duplex ultrasound chance for revision and downsides
12% no technician and equipment available
Angioscope benefit
Assess arm vein conduits as well as for completion of valve lysis
Factors associated with reduced graft patency
1) small conduit < 3mm 2) poor run off 3) high outflow resistance 4) ESRD
Define primary patency, assisted primary and secondary
Primary = patent continuously without any action Assisted primary = intervention but was never occluded (reflection of the surveillance and timely reintervention) Secondary = thrombosed but revived (reflection of surgeon persistence)
Reversed vein vs in situ bypass in patency
same although for small vein < 3mm, in situ seems to be better but not significant
Comparison of primary patency for above knee fem-pop bypass conduit types
Comparable TABLE 109.3
Comparison of primary/secondary patency for below knee fem-pop bypass conduit types
Vein much better than PTFE TABLE 109.4
Comparison of patency for infrapopliteal grafts (tibial bypass)
Vein much better than arm vein and PTFE TABLE 109.5
Pedal bypass results
TABLE 109.6
BASIL key point
1) patients who live > 2 years will benefit from bypass first strategy 2) vein better than prosthetic for CLTI 3) angioplasty then bypass vs bypass, primary bypass better for amputation free survival
Treatment for WIfI clinical stage 4 patients
Open bypass
Factors that increase the risk of graft failure
1) impaired ambulatory status at presentation 2) DM 3) ESRD 4) gangrene 5) prior vascular intervention combination worst
FINNVASC score system
1) DM 2) foot gangrene 3) CAD 4) urgent operation risk on scale of 1-4 based on sum of all points externally validated
PREVENT III prediction model
1) ESRD HD 4 points 2) tissue loss 3 points 3) age > 75 2 points 4) CAD 1 point low risk < 3 pt medium 4-7 high > 8 externally validated
BASIL stratification system
1) tissue loss 2) BMI 3) serum creatinine 4) Bollinger score 5) age 6) smoking 7) CAD 8) ankle pressure complex model not externally validated
PREVENT III complication rates
death 2.7% MI 4.7% major amputation 1.8% graft occlusion 5.2% major wound complication 4.8% graft hemorrhage 0.4% Late complications 1) lymphedema 2) graft infection 3) graft anuerysm 4) graft stenosis
Rate of graft threatening stenosis in 2 years from vein grafts
1/3
Signs of a threatened graft
1) PSV > 300 2) velocity ratio > 3.5 - 4 3) PSV < 45 4) drop in ABI > 0.15
Types of stenosis in vein graft follow up
Solitary stenosis 80% multiple focal lesions 15-20% Diffuse long segment narrowing 3-5%
Principles of PTA of stenotic graft lesions after bypass
1) > 6 month old grafts responds better 2) cutting balloon beneficial 3) no stenting 4) recurrence rate higher than open revision so need surveillance
Surgical open revision of bypass stenosis
1) patch 2) interposition bypass 3) reciting proximal anast 4) jump graft
