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6 Arterial Revascularization
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The CFA is exposed distal to the inguinal ligament, and dissection is continued to the femoral
bifurcation, where the PFA is identied on the
lateral or posterior-lateral side of the CFA.The
surgeon needs to identify the lateral femoral circumex vein that crosses the anterior surface of
PFA; this vein should be suture-ligated and
divided for more distal PFA exposure. Further
visualization of the PFA may require division of
other crossing veins and lateral retraction of the
sartorius muscle [278].
Lateral Approach
The lateral exposure technique allows exposure
of the middle and distal zones of PFA.It is helpful when dealing with a redo groin with extensive
scar tissue or the presence of infection at the
proximal femoral level. It can also be used when
a more distal inow site is necessary to accommodate limited length of venous conduit.
The incision is made parallel to the sartorius
muscle, on either the medial or lateral side of the
sartorius, depending on the exposure needed
based on vessel patency and/or conduit choice.
The sartorius muscle is retracted, exposing the
dense connective tissue membrane extending
from the adductor longus to the vastus medialis.
This membrane is longitudinally incised to
expose the middle zone PFA.If more distal PFA
exposure is required, the adductor longus muscle
is divided [278].
Posterior Approach
This approach exposes the middle and distal
zones of the PFA.
This unusual and rare exposure is needed
when the standard anterior approach is high risk,
as in cases of extensive scarring, multiple redo
surgeries, infection, or other anatomical/surgical
contraindications.
The posterior approach to the PFA is performed with the patient in the prone position. A
longitudinal incision is made lateral to the hamstring muscle group, and the muscles are retracted
medially in the plane between the biceps femoris
and vastus lateralis. The adductor magnus is
incised longitudinally, and the adductor brevis is
also divided, exposing the PFA. Especially in
cases of infection, the adductor longus and its
fascial plane should be preserved and not divided,
as this isolates the current surgical eld from
contamination within the subsartorial canal
[279].
6.17.2 Profundoplasty
6.17.2.1 Indications
The PFA provides the primary blood supply to
the tissues of the thigh and distal leg via genicular collaterals and thus is the most critical collateral vessel in the setting of supercial femoral
artery (SFA) occlusion. Atherosclerosis of the
PFA is usually focal, involving the origin and the
very proximal portion of the artery and sparing
the rest of the vessel. This focal atherosclerotic
disease can be removed and treated with profundoplasty. An isolated profundaplasty can improve
inow to the lower leg in patients with claudication or rest pain [280]. Adequate profunda perfusion is essential in healing major amputations,
specically below-knee amputations. Thus, by
preserving the knee joint, profundoplasty can
also result in a high degree of functional rehabilitation for these patients [281].
• However, isolated profundoplasty is not the
ultimate revascularization in all vascular
patients.
• In patients with critical limb ischemia and signicant tissue loss, profundaplasty alone
without a concomitant distal bypass is insufcient to provide adequate pulsatile inline
ow to the foot.
• Therefore, in certain vascular patients, additional revascularization procedures should be
performed on a case-by-case basis [280].
The likelihood of success after profunda inter-
vention can be indirectly measured using the profunda popliteal collateral index (PPCI).
The PPCI indirectly assesses the amount of
collateral ow between the profunda and popli-
188
PPC
P=−
()
I. Ali et al.
teal arteries. With a robust collateral network,
improving the profunda perfusion can improve
the perfusion to the popliteal artery and more distal vessels, whereas in patients with poorly developed collaterals, increasing the perfusion via the
profunda will not signicantly impact popliteal/
tibial perfusion.
The PPCI is calculated using segmental pres-
sures above and below the knee:
where AKSP is above-knee segment pressure,
and BKSP is below-knee segment pressure.
A PPCI greater than 0.5 indicates poor collateral development and likely failure of a standalone profundaplasty. A PPCI less than 0.2 shows
signicant collateral formation and likely a good
response to stand-alone profundaplasty [282].
IAKSPBKSPBKS
/
6.17.2.2 Technique
Profundaplasty is typically performed in conjunction with femoral endarterectomy. The various techniques will be discussed briey.
The femoral vessels are exposed (see previous
sections), and the SFA, PFA, and CFA vessels are
clamped after systemic anticoagulation. A longitudinal arteriotomy is initiated in the mid-CFA
and extended proximally toward the external iliac
artery (until a soft patent vessel is encountered).
The minutia of femoral endarterectomy will not
be discussed here. The distal endpoint of the arteriotomy can be extended onto either the SFA or
PFA.The PFA should be selected in cases where
the SFA is chronically occluded, and PPCI suggests improved distal perfusion with profunda
intervention. The arteriotomy onto the PFA
should continue until a healthy/patent vessel is
identied.
Endarterectomy is then performed, and the
plaque is removed from the CFA.The PFA plaque
is addressed carefully, where the plaque terminates in a thin, feathered endpoint. Any loose ap
is trimmed sharply and/or tacked down with 7–0
Prolene sutures.
The method of arteriotomy closure has many
variations. The selection of closure method is
inuenced by the occlusive pathology, indications for revascularization, and surgeon experi-
ence. If a patch closure method is chosen, the
patch can be made of Bovine pericardium,
Dacron, autogenous vein, or a piece of endarterectomized occluded SFA segment. The latter two
are the preferred patch materials in the setting of
an infected eld. The most common closure
methods are summarized below. The ultimate
decision in selecting the patch method comes
down to surgeon preference and intraoperative
ndings.
1. Standard Patch:
The patch is cut to length and completed
with either one or two running Prolene
sutures. The patch extends onto either the
PFA or SFA.
If the patch terminates on the PFA, the SFA
can sometimes be transected and ligated, and
the remaining posterior wall of the femoral
vessel is incorporated into the patch anastomosis, or if the SFA is patent, it can be transected and reattached to the femoral vessel/
patch in an end-to-side anastomosis. If the
SFA is selected for the distal endpoint of the
patch angioplasty, the PFA disease can be
addressed in a modied eversion technique.
2. Bifurcated Patch:
Arteriotomy can extend onto both SFA and
PFA, and each vessel endpoint is individually
endarterectomized. The patch is fashioned
with a bifurcated distal endpoint in a “snake
tongue” conguration. A wider patch is typically used in this scenario. The anastomosis
can be completed using separate running
sutures for each patch corner [283].
3. No Patch, Eversion:
The eversion endarterectomy technique
commonly described for the carotid artery can
also be applied to the femoral vessels. The
CFA is transected approximately 1cm proximal to the femoral bifurcation. The proximal
CFA is endarterectomized by the standard
eversion technique. The PFA and SFA are
addressed with a modied eversion technique.
Once the endarterectomy is completed, the
CFA is reconnected with an end-to-end anastomosis, using two Prolene sutures, starting
rst with the back wall [284].
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5. Interposition Graft:
Rarely femoral interposition grafting may
be performed instead of patch angioplasty
when arterial wall integrity appears compromised following endarterectomy; PTFE,
Dacron, or vein can be used as a conduit. This
can be congured in any number of ways:
(a) Distal anastomosis to syndactylized SFA
and PFA.
(b) Distal anastomosis to the SFA with reim-
plantation of the deep femoral artery.
(c) Distal anastomosis to the PFA with reim-
plantation of SFA.
(d) Distal anastomosis to the PFA only when
the SFA is already occluded.
6.17.3 Profunda Bypass
6.17.3.1 Considerations
In the setting of bypass, the PFA can be used as
an inow or outow source, depending on the
clinical scenario.
Fig. 6.78 Depiction of “dropped bifurcation” technique
for patch angioplasty
4. Dropped Bifurcation Technique:
This technique extends onto both PFA and
SFA, similar to the bifurcated patch; however,
it differs in the suturing technique and only
utilizes a simple patch while also elongating
the CFA (Fig.6.78). The arteriotomy extends
onto the PFA and SFA, and endarterectomy is
performed. The suture begins at the apical
junction of the origins of the SFA and PFA
with the knot on the outer posterior vessel surface. One arm of this suture is then run distally to unite the posterior edges of these
arteries to the distal end of the arteriotomies.
This creates a common vessel (extended CFA)
that enables the simple placement of a single
patch, similar to the standard patch technique
[285].
1. Inow Source:
The PFA is a particularly useful inow
source for distal bypass if there is inadequate
vein length or if exposure to the CFA is challenging (i.e., scar tissue, infection, or prior
irradiation). Darling et al. reviewed 2829
infrainguinal reconstructions; 563 (20%) procedures had been performed with the PFA
used as the inow source. The 1- and 5-year
secondary patency rates for all bypasses with
the PFA were 90.4% and 76.9%, respectively,
compared with 88% and 73.3% for CFAbased bypasses [286].
2. Outow Source:
The PFA can be used as outow for aorto-
femoral, axillofemoral, or femoro-femoral
bypasses and should be considered in the setting of challenging CFA anatomy or occlusion. The CFA and PFA often require an
endarterectomy, and the bypass hood is sewn
to both the CFA and the proximal PFA.PFA
can be used alone as an outow source if CFA
exposure is problematic or occluded [287,
288]. Both proximal and distal PFA provide a
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I. Ali et al.
durable outow source. PFA bypass has
results comparable to CFA.Standard aortobifemoral bypass to either CFA or PFA provides
cumulative patency and limb salvage exceeding 90% at ve years [289].
6.17.3.2 Outcomes ofProfunda
Revascularization
Bypass
Axillofemoral bypass remains the standard revascularization procedure for aortoiliac occlusive
disease in patients who are unsuitable candidates
for inline revascularization with aortoiliac or aortofemoral bypass. The reported patency of axillofemoral bypass remains >70% at 5years [110].
Axillofemoral bypass provides a favorable revascularization option in patients who have signicant surgical risk. There are no reported studies
comparing patency and outcomes of axillo-PFA
bypass compared to CFA.
Profundoplasty
Profundoplasty is a durable, safe, and effective
procedure in patients with SFA occlusion and/or
CFA stenosis extending to the PFA ostium. For
patients with Rutherford category 5 and 6 ischemia, the profundoplasty alone is not considered
adequate, and concomitant distal bypass should
be planned to improve limb salvage rate. Fiveyear patency of profundoplasty is excellent and
quoted to be >90% [110].
Open Vs. Endovascular
Endovascular treatment of PFA is less durable
than profundoplasty but may be an acceptable
alternative in selected patients who are at highrisk for surgery or as a secondary intervention to
maintain the assisted patency of a bypass graft
when the PFA was used either as a bypass outow target or as an inow source.
Endovascular intervention access can be
approached from a contralateral common femoral access in an “up-and-over” the aortic bifurcation fashion or an ipsilateral radial or brachial
access. There is a risk of embolization or occlusion of the patent SFA from the balloon angio-
plasty; placing a “buddy wire” into the SFA
should be considered to maintain access to the
SFA for rescue interventions if any of these
events occur.
Qato etal. reviewed 105,568 lower extremity
endovascular interventions. Of those procedures,
361 (0.3%) were performed for isolated PFA
occlusive disease. The most common treatment
modality was plain balloon angioplasty (58.5%),
angioplasty followed by stent (18.6%), drugcoated balloon angioplasty (10.0%), atherectomy (9.4%), and stent graft (3.6%). Overall
primary patency at 13months was 92.9% [290].
Currently, there are no reported data that directly
compare endovascular vs open treatment of PFA
disease. Endarterectomy remains the standard of
care and has consistently demonstrated durable
results.
6.18 Don’t Mess
withtheProfunda... Unless
NealKhurana and ChadLaurich
The profunda femoris artery (PFA), also known
as the deep femoral artery, arises posterolaterally
from the distal common femoral artery (CFA). Its
main branches are the medial and lateral circumex femoral arteries and three perforating muscular branches. Around the hip, the circumex
branches of the PFA anastomose with branches
of the internal and external iliac arteries.
The PFA’s primary function is to perfuse the
thigh. In the setting of critical limb ischemia
(CLI), the PFA becomes more critical as it provides collaterals to the popliteal and infragenicular arteries.
Preservation of the PFA in CLI management
is crucial. Profundaplasty during CFA endarterectomy is common. The PFA can also serve as
an inow source for bypass. The PFA can also
serve as an inow source for bypass [291]. The
PFA is not commonly treated with endovascular techniques as risk of dissection or occlusion
can result in poor clinical outcomes that are
complex to manage, as ow to distal PFA
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191
Fig. 6.79 Nonsurgical patient with critical limb ischemia. Pelvic angiogram demonstrates severe stenosis of
the right external iliac artery (a) and chronic occlusions
of the right CFA (b) and right PFA (c)
branches is necessary for stump healing after
amputation. However, PFA endovascular intervention can be performed in highly selected
cases including patients who have high surgical
risk, short life expectancy, or wound-healing
considerations.
Endovascular optimization of PFA ow may
be the only “bailout” option for limb salvage
(Figs. 6.79 and 6.80). Angioplasty alone has
shown good long-term patency and limb salvage
rates [292]. Drug-coated balloon angioplasty,
stenting, and atherectomy of the PFA have all
been reported without signicant patency rate
differences among modalities with 92% patency
at 13months and up to 73% at 24months [293,
294]. However, reintervention is more likely in
patients treated just with plain balloon angioplasty [293]. In regard to stenting, there is signicantly higher mean primary patency at
12 months for routine stenting compared to a
selective stenting strategy (91.4% versus 75%;
p<0.05) [294].
Fig. 6.80 Post-treatment angiogram of the right external
iliac artery (a), right CFA (b), and origin of the right PFA
(c) demonstrates signicant luminal gain throughout and
inline ow into the right PFA
In conclusion, the PFA is an important factor
in managing CLI and endovascular treatment is
safe and effective in select patients, namely high
surgical risk.
6.19 Pedal Surgical Bypass
SamuelJessula, ClaudiaCote, and AnahitaDua
6.19.1 Introduction
The goal of a surgical bypass for treatment of
CLTI is to restore pulsatile inline ow to the
affected area, typically the foot [295]. Therefore,
the distal anastomotic site should be the most
proximal outow target vessel that has at least
one continuous runoff artery to the tissue bed in
need of revascularization. In patients with
occluded tibial vessels and CTLI, hemodynamically signicant lesions distal to the popliteal
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I. Ali et al.
artery and femoral-popliteal bypass would provide insufcient. In such patients, a pedal bypass
may provide the optimal perfusion with durable
results.
6.19.2 Patient Selection
Indications for pedal bypass include tissue loss or
rest pain with or without concomitant infection in
the absence of a more proximal outow target.
Patients with diabetes typically present with tibioperoneal occlusions and preserved aortoiliac
and femoropopliteal vasculature and thus present
ideal candidates for pedal bypass [296].
• Up to 60% of patients with diabetes will heal
ulcers after revascularization [297].
• Pedal bypasses are contraindicated in the context of active infection at the site of planned
incisions such as ascending foot infections
and are very rarely performed for patient with
claudication alone without rest pain or tissue
loss.
6.19.3 Inow Selection
with non-statistically signicant increased primary patency at 1year (67 vs 48%) and had
no effect on graft occlusions within 1month
or limb salvage within 1 year in patients
undergoing pedal bypass [302].
6.19.4 Outow Selection
Outow targets are selected based on the distribution of atherosclerosis in the lower extremity
vasculature.
• Ideally, a patent continuity of the plantar and
pedal arch would be present, thus providing
ow to the entire foot; however, this is not
mandatory [303].
• In the context of both a patent dorsalis pedis
and perimalleolar posterior tibial artery, the
dorsalis pedis can be favored as it is an easier
anastomosis on the dorsum of the foot.
• In the context of an incomplete plantar arch, if
a wound is present on the plantar surface of
the foot, the posterior tibial artery may be
selected in keeping with the concept of the
angiosome, as this vessel will provide direct
inline ow to the ischemic area [304].
Patients with preserved femoral–popliteal ow
are candidates for “short bypasses” with inow
targets such as supercial femoral artery or popliteal artery his provides the advantage of avoiding a groin dissection and its associated morbidity,
decreasing the length of the surgical incisions,
shortening operating time and requiring less
length for the conduit, thus increasing the probability of using autologous vein [298]. These
advantages provide satisfactory long-term
patency, even in the context of worsening supercial femoral disease and may be combined with
less invasive procedures to ensure adequate
inow [299–301].
• Prior tibial endovascular interventions should
not preclude individuals from being candidates for pedal bypass. Uhl etal. demonstrated
that, compared to no prior intervention, previous endovascular intervention was associated
Of note, angiography alone may underestimate the ow in a pedal vessel and the presence
of a Doppler signal should prompt operative
exploration (so-called blind exploration) for
potential pedal target. Pomposelli et al. performed 6 successful pedal bypasses out of 12
candidates with no angiographic evidence of ow
but with a present Doppler signal on physical
exam [305]. Similarly, Eiberg etal. completed 5
bypasses on arteriographically occult distal artery
targets with only 2 graft occlusions within 1year,
of which one patient remained asymptomatic
[306].
6.19.5 Conduit Selection
Similar to femoropopliteal bypasses, the success
of pedal bypasses greatly relies on the quality of
the conduit [307].
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• Autologous vein continues to be the favored
conduit for any bypass, and this remains true
in the setting of pedal bypass and all efforts
should be made to avoid synthetic grafts.
Pomposellli etal. described their vast experience with pedal bypasses and techniques to
minimize the use of synthetic grafts [308].
Their group prioritized saphenous vein over
any conduit, followed by upper extremity
vein, and then lesser saphenous vein.
• If the limitation is inadequate length of venous
conduit, composite vein can be used or a more
distal inow target, such as supercial femoral
or popliteal artery may be selected, even in the
context of a diseased artery as long as the
lesion is not considered ow limiting.
• Finally, in the absence of any other conduit or
bypass congurations, synthetic graft material
may be employed although is strongly discouraged [308]. Saphenous vein is associated
with improved patency compared to other
conduits (other vein and synthetic) (68% vs
46% at 5 years) [309]. As such, the importance of meticulous preoperative vein mapping cannot be understated [310, 311].
induced. Inow exposure is performed in routine
fashion. Briey, the common femoral artery is
approached through a vertical incision under the
inguinal ligament in the groin. The supercial
femoral artery can be identied as the continuation of the femoral artery and the same incision
can be lengthened as needed. The supra and
infragenicular popliteal artery can be exposed
through medial incisions above or below the
knee, respectively.
Outow exposure remains quite simple,
emphasizing the elegance of a pedal bypass. As
the dorsalis pedis is very supercial, the dissection is relatively easy compared to other vascular
beds. The dorsalis pedis artery is the continuation
of the anterior tibial artery and lies medial to the
extensor hallucis longus tendon down to the
proximal space between the rst and second
metatarsals on the dorsum of the foot [312].
Doppler identication is important prior to incising as signicant variability exists in how lateral
the dorsalis pedis artery lies [313, 314]. A longitudinal incision is performed slightly lateral to
the Doppler signal of the artery on the dorsum of
the foot, between the rst and second metatarsal,
When using saphenous vein, it can be
employed in the in situ conguration, reversed or
non-reversed. In situ has the disadvantage of
requiring use of the segment of vein immediately
adjacent to the lesion being bypassed, thus limiting which segment of vein can be used. Therefore,
transposed saphenous vein is generally preferred.
Pomposelli etal. found no statistically signicant
difference with the use of reversed vs nonreversed saphenous vein [309]. On meta- analysis,
the reversed conguration displayed slightly
higher primary patency (83% vs 78% at 1year
and 66% vs 59% at 5 years) and secondary
patency (88% vs 84% at 1year and 73% vs 67%
at 5years); however, this was not statistically signicant [307].
6.19.6 Operative Technique
The patient is placed supine on the operating
room table and general or regional anesthesia is
branch of the supercial peroneal nerve is identied and retracted laterally, underneath which the
deep fascia is incised to expose the neurovascular
bundle. The extensor hallucis longus and brevis
are separated and the dorsalis pedis is identied
lateral to the deep peroneal nerve [312]. Care is
taken to preserve the medial and lateral tarsal
branches of the dorsalis pedis [313, 314].
The distal posterior tibial artery lies posterior
to the medial malleolus, between the exor digitorum longus tendon and the exor hallucis longus muscle before passing under the exor
retinaculum to enter the foot [312]. To expose it,
the patient’s leg is externally rotated and exed
60° at the knee. A vertical incision is performed
1 cm posterior to the distal tibia and curved
around the medial malleolus. The exor retinaculum is then divided exposing the neurovascular
bundle in a groove formed by the tendons of the
exor digitorum longus and the exor hallucis
longus. The posterior tibial artery is found anterior to the tibial nerve [312].
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I. Ali et al.
Once the inow and outow arteries are
exposed, the graft is tunneled as needed and the
patient receives systemic heparin. The anastomoses are performed in a standard fashion with continuous permanent monolament suture.
Completion angiography or angioscopy can be
performed selectively at case completion to conrm adequacy of bypass [303, 315]. All incisions
are closed primarily.
• Postoperatively, patients are administered
81mg of aspirin daily for life and prophylac-
tic heparin while in hospital.
• Postoperative foot edema is common, and best
treated with leg elevation and elastic wrapping
[309].
• Patients are instructed to avoid weight bearing
on the operative foot for 2–7days.
6.19.7 Outcomes
In the largest series of pedal bypasses, operative
mortality was <1% with a 4.2% 30-day graft failure rate, of which one third were successfully
revised [309]. Primary patency was 57% and
38%, while secondary patency was 63% and 41%
at 5 and 10years, respectively.
• Limb salvage was 78% at 5years and 58% at
10years. On multivariable analysis, increased
length of stay (OR 0.95, 95% CI 0.93 to 0.98)
and graft occlusion as indication (OR 0.38,
95% CI 0.17 to 0.89) were signicantly pre-
dictive of graft failure at 1year, while use of
the saphenous vein as conduit was protective
(OR 1.82, 95% CI 1.25–2.65) [309].
• On meta-analysis of over 2320 pedal bypasses,
30-day mortality had a weighted average
2.6%, and 1-year mortality was 13%. 1-month
outcomes demonstrated primary patency of
93%, secondary patency of 95%, and foot
preservation rate of 95%.
• 5-year outcomes demonstrated primary
patency of 63%, secondary patency 71%, and
limb preservation of 78% [307].
On meta-analysis, compared to dorsalis pedis
bypass, tibial bypass was favored for primary
patency (86% vs 77% at 1year, 69% vs 57% at
5 years), secondary patency (90% vs 81% at
1year, 76% vs 65% at 5years), and foot preservation at 5years (80% vs 76%) [307]. However,
the meta-analysis did not comment on whether
the tibial artery target was proximal or distal, thus
rendering a true comparison between distal/perimalleolar tibial artery vs dorsalis pedis artery
difcult.
6.19.8 Alternatives toPedal Bypass
Tibial angioplasty would provide an alternative
to short pedal bypass for lesions isolated to the
tibial vessels. Ferraresi etal. reported the largest
series of 107 isolated tibial angioplasties with a
procedural success rate of 94%, a restenosis rate
of 42%, and a limb salvage rate of 93% at a
median follow-up of 1.4years [316].
• In the event of an occluded dorsalis pedis and
paramalleolar posterior tibial artery, revascu-
larization to a more distal target, such as to a
plantar or tarsal vessel, is feasible.
• Hughes et al. report successful bypass of 77
plantar and 21 tarsal arteries in patients of
which 18 had previous revascularization
including 5 previous dorsalis pedis bypasses
[317].
– 30-day mortality was 1% and 30-day graft
occlusion occurred in 11%.
– Primary, secondary patency, and limb sal-
vage rates were 67%, 70%, and 75% in
1year and 41%, 50% and 69% in 5years,
respectively [317].
Although not technically considered a pedal
vessel, the peroneal artery can be an alternative
outow target if patent on preoperative imaging.
Darling etal. reported a series of 159 patients with
bypasses to the distal peroneal artery, demonstrating a primary patency of 86% at 30days, 82% at
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1year, and 69% at 5 years [318]. The secondary
patency was 86% at 1year and 75% at 5years,
with a limb salvage rate of 87% at 5years [318].
• When compared to tibial and pedal bypass,
peroneal bypass has increased secondary
patency (55% vs 67%) but decreased limb salvage (33% vs 46%) at 2years [319].
6.19.9 Target Limitations
Pedal bypasses cannot be performed if there is
active infection over the intended incision for the
distal anastomosis and thus cannot be performed
in the context of an active, ascending infection of
the foot. Furthermore, the poor outcomes of synthetic grafts in pedal bypasses limit the applicability of the procedure in patients with absent vein
conduit. If a pedal bypass fails, a redo pedal bypass
may be considered; however, it requires the availability of another vein conduit and patency is poor,
especially if failure was within 30 days [320].
Finally, although pedal bypass has demonstrated
robust durability, endovascular technologies are
rapidly progressing and may at some point outperform bypasses. To date, no trials comparing the
two techniques have been published.
6.19.10 Conclusion
Pedal bypass is a straightforward, reliable technique for revascularization of CTLI with acceptable long-term patency and limb salvage rates. It
should be considered in patients with ischemia
and a distal pedal Doppler signal or angiographic
ow.
Pearls:
• Ensure adequate preoperative vein mapping
and prioritize saphenous vein conduits when
feasible.
• Consider exploration of any artery with a
Doppler signal on physical exam, even in the
absence of angiographic evidence of ow.
Pitfalls:
• Avoid prosthetic conduits at all costs.
6.20 Intravascular UltrasoundBased Femoropopliteal
Atherectomy Selection
BryanFischer
The popliteal segment represents one of the most
difcult vascular beds to treat for multiple reasons, the most striking being the stress placed on
the vessel during knee extension and exion.
This has been illustrated by the historical failure
of traditional scaffolding secondary to fracture
and further supported by a relative paucity of
devices that are considered on label for this segment. As with the SFA, popliteal occlusive disease is often treated with vessel preparation
followed by denitive therapy (DCB/scaffold).
Modication and/or plaque debulking with atherectomy is often part of the toolbox aimed at
reducing the disease burden before moving on to
the next step.
A wide variety of atherectomy devices are
approved in the USA, and this number continues
to grow despite a relative paucity of high-quality
data to support its use [321, 322]. However, in the
real-world setting, interventionalists across each
of the vascular interventional specialties have
found atherectomy to be a helpful tool in their
toolbox. The decision of which device to use lies
with the interventionalists comfort level/expertise and the ability to apply the appropriate treatment to address a particular disease morphology
based on intraprocedural ndings. This is the
most important component of a successful treatment algorithm and reiterates the need to have a
selective and personalized approach to each individual patient.
Identifying the type of lesion is a key to
choosing the appropriate atherectomy device in
the popliteal space. Luminal size and landing
zone planning are also key to procedural success. For this reason, advanced intraprocedural
196
I. Ali et al.
imaging is paramount to achieving the desired
end result for treating symptomatic occlusive
disease in the popliteal artery. Angiography,
while widely accepted as a reliable reference of
vessel characteristics, has been shown to be
inadequate [323].
The use of either EVUS/IVUS has proven to
be reliable in such cases. Once IVUS-based
assessment of the underlying lesion morphology,
intervention can be planned [323].
Rather than discussing a given morphology
type and the resulting choice of atherectomy
device, it may be more helpful to know where
devices have known limitations. Few scenarios
dwarf the morbidity of complications that ensue
when a device is chosen for the wrong disease
morphology. For instance, some devices are
almost certain to cause distal embolization in
very soft plaque or luminal thrombus. Each has
its strengths and weaknesses that will be
addressed.
6.20.1 Calcied Plaque
Calcied disease is the disease morphology for
which most atherectomy devices perform poorly
with regard to luminal gain or plaque modication. The appearance of calcium is obvious with
IVUS interrogation and can often be appreciated
in less detail with uoroscopy [323].
• Traditionally, orbital atherectomy has done
well by sanding the lesion in a controlled fash-
ion. While some routinely use distal protec-
tion, deliberate escalation of rotation speeds
and advancing in a slow but steady fashion is
effective at mitigating embolization risk.
Laser is not traditionally thought of as rst-
line treatment for bulky calcied disease;
however, several operators have demonstrated
an ability to successfully cross calcium-rich
lesions and modify less dense calcied dis-
ease. Again, a slow and deliberate approach is
necessary and achieved by allowing the device
to vaporize plaque with steady forward pressure. Though it takes several passes with escalating energy, many operators are surprised by
the luminal gain achieved that can be seen
clearly with intravascular ultrasound.
• Other atherectomy devices like phoenix and
directional atherectomy are capable of achieving luminal gain by plaque removal but have
been known to require a higher skillset for
successful operation. Knowing the device and
being facile with its use is key [324, 325].
6.20.2 Fibrous Plaque
Fibrous disease morphology represents an altogether different type of challenge with regard to
atherectomy effectiveness.
• While orbital atherectomy does well with calcied disease, other devices tend to perform
better here [326].
• Directional atherectomy has tremendous
upside with the ability to debulk lesions in a
deliberate fashion. The resultant luminal gain
combined with the appropriate denitive therapy can lead to a good result and the return of
pulsatile inow to the tibial vessels.
• Most use distal protection in the event of distal
embolization, a known but accepted risk given
the upside of successful debulking [327].
• Laser also performs well here, and luminal
gain is readily apparent with IVUS.Dissections
are often seen with laser, the extent of which
can vary based on energy delivery and number
of passes [328].
• Luminal gain is less efcient than directional
atherectomy but can still be achieved.
• Hybrid devices like phoenix are also effective
here when operators can effectively apply
device deection with an enlarging radius.
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