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Fig. 21.13 Proximal (top panel) and distal (bottom
panel) anastomoses of a femoral-tibial graft. Note absence
of kinking or “pull” on the anastomosis, with no
redundancy
Fig. 21.14 Popliteal to dorsalis pedis bypass, with translocated vein harvested from the upper thigh (solid dark
arrow). Note the vein graft is translocated to a subcutaneous position where no incision has been made in the calf
and lower leg (dashed dark arrow)
Fig. 21.15 Same patient as Fig.21.14, demonstrating the
proximal anastomosis to the below-knee popliteal artery
M. C. Siah et al.
Fig. 21.16 Same patient as Fig. 21.14. The graft has
been tunneled subcutaneously to the dorsalis pedis artery
and the distal anastomosis has been performed
(Fig.21.14). After preparation of the graft with
angioscopy, the proximal anastomosis is performed in an end vein to side artery fashion to the
popliteal artery (Fig.21.15). After completion of
the anastomosis, the graft is placed in the previously created tunnel to the dorsalis pedis incision
under arterial pressure (to avoid kinking or twisting of the graft) and the distal anastomosis is then
performed (Fig. 21.16). A handheld continuous
wave Doppler is used to insonate the distal anastomosis and distal artery. We rarely perform completion arteriography, though some surgeons
utilize it routinely. Estimated blood loss is usually 150mL or less.
In many patients with CLI, the only suitable
target for revascularization is a distal inframalleolar vessel, such as the plantar or tarsal artery.
Bypass to these vessels, though technically challenging, can be performed successfully through
accurate angiographic visualization preoperatively, anatomic knowledge of the plantar and
tarsal vessels, and by incorporating meticulous
surgical and vein harvest techniques (Figs.21.17,
21.18, and 21.19). Increasing experience has
shown excellent short-term and long-term
patency and limb salvage rates, which is highly
encouraging in this particular subset of patients
who are often advised to undergo limb
amputation.
When ipsilateral saphenous vein is not available, the decision for an alternative source of
conduit should be made with consideration of
the patient’s comorbidities. Contralateral saphenous vein may be used, though up to 60% of
patients will require contralateral revasculariza-
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Fig. 21.17 Arteriogram of the foot in a 60-year-old
patient with a gangrenous hallux, demonstrating only a
plantar vessel in the foot
tion within 2 years. Several reports also have
attested to the success of arm vein grafts; however, enthusiasm is tempered by their limited
length. In addition, an increasing number of
patients with CLI will have either chronic renal
insufciency or end- stage renal disease, and the
arm vein should not be sacriced in these patients
in whom optimal angioaccess is essential for
survival.
Based on these limitations, prosthetic grafts
have been increasingly used in the tibial location
for patients with limited autogenous conduit,
with encouraging results. Newer developments
and advancing techniques, such as heparinbonded polyuorotetraethylene (PTFE) and vein
cuffs/patches at the distal anastomosis, have
resulted in improved patency rates in some
series.
Fig. 21.18 Same patient as Fig.21.17. The plantar ves-
sels have been exposed and the vein graft is prepared for
distal anastomosis (top panel). Distal anastomosis performed to the junction of the medial and lateral plantar
arteries (solid and dashed arrows) (bottom panel)
Our preference is to use the contralateral
saphenous vein only in those patients who have
a palpable foot pulse or near-normal noninvasive arterial studies. Our second preference is a
prosthetic PTFE graft which I modify by performing a vein patch at both the proximal and
distal anastomosis. The patch is sewn widely
onto the recipient vessel, with a generous PTFE
anastomosis on the top of the patch (Fig.21.20).
By performing this at the proximal anastomosis, we have not encountered a patient who
presents with severe limb ischemia from proximal propagation of thrombus should the graft
occlude.
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M. C. Siah et al.
Fig. 21.19 Angiogram 1year postoperative and Duplex 2years postoperative of the patient from Fig.21.17, demon-
strating a widely patent graft
Complications
Both systemic and local complications may occur
after surgical revascularization. Perioperative
cardiac complications are the most common systemic complication, occurring in up to 5% of
patients, and include arrhythmias, congestive
heart failure, and myocardial infarction.
Perioperative use of beta-blockers may reduce
this risk. Judicious use of uids, intraoperative
monitoring with liberal use of nitrates, and a high
index of suspicion for myocardial ischemia
Fig. 21.20 Distal anastomosis of a PTFE graft with distal vein patch to the peroneal artery. Note the wide vein
patch on the native artery with the PTFE graft anastomosed to the patch
remain as important tenets of postoperative care.
The incidence of early (immediate) postoperative graft occlusion varies according to the loca-
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Fig. 21.21 Four weeks following left femoral to tibial
bypass, complicated by a supercial wound dehiscence,
this patient presented with bleeding in the groin incision
tion and obviously varies among individual
surgeons; most series report a rate of approximately 2–5%. Unless otherwise dictated at the
time of the original operation, or otherwise mitigating circumstances, all patients with early graft
occlusion should be re-explored and graft
thrombectomy performed. Most importantly, an
underlying cause (such as an anastomotic ap or
clamp injury) should be sought and addressed, as
the outcome is more favorable when the cause is
corrected.
Wound complications are often underreported, and probably the most frequent complication after infrainguinal bypass surgery. The
spectrum ranges from simple cellulitis which
may be treated with antibiotics alone, to extensive soft tissue infection with graft involvement.
Most often, the sequence is that of an indolent
infection which results in a small area of wound
dehiscence and brinous exudates. Unfortunately,
this can mask deeper involvement, which can
result in a catastrophic outcome if the graft is
involved (Fig.21.21). The most important treatment is prevention. Accurate and precise tissue
approximation and closure, avoidance of aps,
judicious use of antibiotics, prevention of lymph
(top panel) with a large infected pseudoaneurysm by CT
scan. This necessitated emergent groin exploration with
debridement and graft removal (bottom panel)
leaks, and clean dressings all can help prevent
wound complications. Additionally, as stated previously, we will avoid placing grafts in the subcutaneous space of a surgically created incision. In
the femoral location, use of a rotational sartorius
muscle ap is quite helpful to cover the graft
prophylactically.
Results
Patency rates and limb salvage after surgical
revascularization vary widely, principally according to the anatomic location, though other factors
(such as re-do procedures, type of conduit, and
indication) also are important determinants. The
highest patency rates are seen with in-line (anatomic) inow operations, with 5-year and 10-year
patency for aortobifemoral bypass being 90% and
80% respectively. Similar rates are seen following
isolated profundaplasty or femoral endarterectomy. For extra-anatomic bypass, the results are
obviously lower, with 5-year patency for femoralfemoral bypass averaging 65%. Among axillobifemoral grafts, the patency rates are even lower,
averaging between 40% and 60% at 3years.
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M. C. Siah et al.
Bypass grafts with saphenous vein provide the
highest patency rates among infrainguinal revascularization. In situ and reversed vein graft primary patency at 1 year and 4 years averages
approximately 85% and 65% respectively, again
with no difference based on vein conguration.
For paramalleolar bypass grafts, secondary
patency is approximately 60% at 5 years, with
limb salvage rates in excess of 80% at 5years.
The reported patency data for prosthetic grafts
vary widely, with expected 1 year patency
between 35% and 75%. Multiple factors may
explain this wide variation. At least some of the
reports are 20years or older; additionally, variables such as use of a distal vein cuff, anticoagulation, and outow are widely discrepant or not
even reported. More recent data are more encouraging, and certainly support the use of prosthetic
grafts to the popliteal or tibial location when
good quality autogenous vein is not available.
In addition to patency, quality of life scores
need be considered after any intervention, but
especially after infrainguinal bypass among
patients with foot ulceration. In this subset of
patients, time for healing can take up to
3–6 months, with only 50% reporting “back to
normal” at 6 months. Signicantly, approximately 15% of patients who were independent
preoperatively require some level of dependence
at 6 months postoperatively. Finally, the best
measure of quality of life is freedom from major
amputation, as amputation is uniformly associated with the lowest quality of life score.
Choice ofSurgical Revascularization
or Endovascular Procedure
The decision for surgical revascularization or
percutaneous endovascular intervention is dependent on multiple variables, including both patient
variables and the skill of the interventionalist/surgeon. Notwithstanding the debates on which
should be performed rst, it is axiomatic that the
patient with CLI is best served by an aggressive
approach to limb salvage, which, by denition,
incorporates both endovascular and surgical
approaches.
A suggested approach to the patient with limb
ischemia may be guided by the results of the
BASIL trial, which was the rst and only intention to treat randomized controlled trial comparing endovascular intervention to surgical bypass
as “rst treatment” among patients with severe
limb ischemia. At follow-up of 7.7years, 56% of
patients had died, emphasizing the precarious
medical condition of these patients. At 2years,
there was no difference in amputation free survival or overall survival among the two treated
groups, with a slight increase in overall survival
and amputation free survival favoring bypass surgery at 3years. Hospital costs were signicantly
higher for bypass surgery, but this had equalized
at 3years among the two groups. Finally, in the
analysis of quality of life, the worse outcome was
seen among patients undergoing major limb
amputation, again emphasizing an aggressive
approach to limb salvage in these patients.
The results of these and other smaller nonrandomized series suggest that an endovascular-rst
approach is warranted in almost all patients, provided that it may be performed without “burning
a bridge” for future surgical revascularization.
This is especially applicable for patients who are
expected to live less than 2years, based on the
BASIL results. Conclusively, it can be stated that
limb amputation should be avoided, and surgical
revascularization plays an integral part of that
goal.
General Considerations
inEndovascular Revascularization
In 2000, the TransAtlantic Inter-Society
Consensus on the management of PAD, authored
by vascular surgeons, cardiologists, angiologists,
and interventional radiologists aimed to address
the variation in therapy among individual patients
with identical conditions, with an aim to promote
uniform high-level care across different countries. The document stated that “in general, if
there is a balanced choice between an endovascular and a surgical procedure for a particular
lesion, then the former is preferred because it
usually avoids a general anaesthesia, poses a
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lesser systemic stress, and has fewer serious
complications” (14). Encouraged by this vision,
in the next 20years we observed a widespread
increase of endovascular procedures in patients
with CLTI, with many authors advocating an
“angioplasty rst” revascularization strategy
(15–20).
Interventional physicians rode this endovascular wave, developing new technical approaches,
such as endoluminal and subintimal crossing of
long occlusion and retrograde approaches able to
increase procedural success. Manufacturers of
medical devices followed them, producing new
dedicated tools, able to ablate and dilate long and
often calcied lesions, to scaffold vessel wall
preventing recoil and dissection, and to deliver
antiproliferative drugs to avoid restenosis.
Despite this huge effort, even in high-income
countries with advanced health care systems,
such as Germany and the United States, many
patients with CLTI do not always undergo angiography or any attempt at revascularization (21,
22). For this reason, it is important to keep in
mind that a low-cost balloon angioplasty with
uncoated balloons and bailout stenting has been
demonstrated from the beginning to be effective
in preventing amputation in the majority of
patients with CLTI (15, 23–26).
Instead of pursuing a high-cost and high-tech
angioplasty in few fortunate patients our duty
should be to promote and guarantee a widespread access to basic endovascular revascularization to the vast majority of patients with
CLTI, independently from census and country.
In line with this assumption, the purpose of this
chapter is not to describe the newest and most
advanced devices and techniques, but to overview the basic technical strategy that should be
used everywhere by skilled physicians for changing the fate of CLTI at a reasonable cost.
Targets ofEndovascular
Revascularization
According to the new Global Vascular
Guidelines (GVGs) a successful revascularization in CLTI, particularly in patients with tissue
loss, nearly always requires restoration of pulsatile in-line ow to the foot (27). In presence
of diffuse BTK disease, typical of CLTI, the
rst step is to identify the target arterial path
(TAP) in each patient by high-quality imaging,
selecting a preferred infrapopliteal artery. The
TAP is generally based on the least diseased
crural artery providing runoff to the foot and
other relevant factors, such as angiosome preference or avoidance of a previously instrumented vessel (27).
In the last years multiple studies have supported the concept that direct revascularization (DR) of the angiosome affected by tissue
lesion leads to improved healing and limb salvage rates in patients with CLTI (28–35). In
line with the angiosome concepts, the endovascular treatment of patients with CLTI has
evolved toward extreme approaches, and BTA
interventions are proposed as a new strategy to
improve the clinical outcomes of revascularization (36, 37).
In summary, the key point in our revascularization strategy is to identify the proper TAP in
each patient with CLTI, considering many factors such as anatomy, obstructive disease pattern, and technical hurdles that must be
overcome to achieve, if possible, a successful
recanalization.
Anatomic Considerations
inEndovascular Revascularization
The TAP must be evaluated by high-quality
imaging, applying standard foot projections
and digital post-processing methods. About
7% of the patients present some type of anatomical abnormality in the distribution of BTK
vessels at the ankle: anterior or posterior dominance of peroneal artery or a single peroneal
artery (38). Moreover about 20% of the patients
have some variations in the foot vessel anatomy with dominant dorsalis pedis or plantar
artery or a tarsal loop. Every patient is different and to recognize the true underlying anatomy is of fundamental importance in guiding
our procedure (38).
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M. C. Siah et al.
Evaluation oftheCollateral Vessel
Network
Angiosomes are interconnected by a collateral
vessel network which guarantees blood ow to
the entire foot in case of occlusion of one or
more arteries (39, 40). In cases when diffuse disease prevents the DR of the injured angiosome,
some authors suggest to seek a collateral-vesselguided revascularization (41, 42). Other authors
demonstrated that indirect revascularization
through collaterals can effectively promote the
healing of ulcers and decrease the amputation
rate (34, 35, 43).
The evaluation of collateral vessels is a key
point in guiding our revascularization strategy in
patients with CLTI.The value of an angiosomeoriented revascularization is directly correlated to
the degree of SAD affecting the foot distribution
system, and inversely correlated with the expansion of the collateral vessel network (38).
Metabolic Demands ofTissue Loss
angiosome in 24.2% legs, two angiosomes in
46.6%, three angiosomes in 26.1%, four angiosomes in 2.5%, and ve angiosomes in 0.6% legs
(45). They concluded that the tissue lesion of
CLTI affects several angiosomes in majority of
the cases, suggesting that consensus needs to be
achieved for the accurate denition of angiosometargeted revascularization when more than one
angiosome is clinically involved. Some authors
suggest to pursue a multiple BTK vessel recanalization, because this approach can obtain a better
wound perfusion, improving healing speed and
compensating for restenosis of one of the treated
vessels. On the other hand, it is suspected that the
procedure may carry a higher risk due to greater
contrast volume, longer procedure time, radiation
exposure, and potential complications (46–48).
The GVGs assert that multivessel (tibial) revascularization may be reasonable in selected
patients with advanced limb-threatening lesions
(e.g., WIfI stages 3 and 4) undergoing endovascular therapy if it can be safely accomplished
without risking loss of a bypass target or compromising runoff to the foot (27).
According to the GVGs, angiosome-guided
revascularization may be of importance in the
setting of endovascular intervention in patients
with signicant wounds (e.g., WIfI wound grades
3 and 4), particularly those involving the midfoot
or hindfoot, but is likely to be irrelevant for ischemic rest pain and of marginal value for most
forefoot lesions and minor ulcers (27). Wounds
have a different blood ow requirement for healing. The value of revascularization, and particularly an angiosome-targeted revascularization,
varies according to the type of wound (38).
Multivessel Versus Single-Vessel
Revascularization
Every lesion starts generally well localized; however delayed referral and infection lead to its
enlargement, invading surrounding tissues and
adjacent angiosomes (44). Spillerova etal., evaluating patients with CLTI and foot lesions,
observed that the wound interfered with one
Technical Approaches
inEndovascular Revascularization
This is not meant to be a treatise on the endovascular treatment of inferior limb vessels; it merely
highlights the key technical elements to consider
when facing patients with CLTI.
Chronic Total Occlusions (CTOs)
Crossing Strategy
CTOs represent the majority of the obstructive
lesions encountered in patients with CLTI (49).
Crossing the lesion is the rst step of endovascular recanalization. Independently of the site of the
lesion (above-the-groin inow, femoro-popliteal
or infra-popliteal) we recommend a step-by-step
approach. The rst attempt is endoluminal crossing. In many cases a soft tip, hydrophilic wire can
cross the occluded lumen, also in very long
occlusion, nding easily the true distal lumen.
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The explanation of this success resides in a softer
core of the occluding material, surrounded by
stiffer and often calcied walls: the wire slides
inside the core, supported by dedicated low prole catheters or balloons. In case of resistant
brous cap or focal calcication, the soft tip wire
can be exchanged with a CTOs dedicated wire.
The stiffer and often tapered tip can pierce the
tough material, oriented by the operator in the
correct direction.
In case of failure of the endoluminal approach,
the subintimal approach offers an effective alternative. The wire is typically advanced in a looped
shape, and instead of crossing the lumen, the
operator dissects the subintimal space. The discovery of the subintimal space by Bolia was a
major development in angioplasty technique (51,
52). At the end of the CTO, reentry inside the true
distal lumen can be achieved by pushing the wire;
however, due to the risk of damaging the distal
vessel, especially in case of a diseased target, retrograde approaches are preferred.
The retrograde approaches have demonstrated
to be safe and effective, and to increase by 20%
the success rate of peripheral endovascular procedures (53, 54). Every vessel below the CTO
can be used for a retrograde approach, from the
metatarsal arteries to pedal, tibial, and peroneal
artery. The retrograde puncture of tibioperoneal,
popliteal, and supercial femoral artery can be
performed without changing the supine position
of the patient on the radiological table. In the
majority of the cases it is possible to use a sheathless approach, supporting the wire with low prole catheters or balloons. Rendezvous with the
antegrade approach can be accomplished in the
endoluminal or subintimal space, sometimes
with the help of balloons dilatation.
Other approaches were described, transcollateral, pedal-plantar loop, and can be used in
particular cases with the advice to respect what is
functioning and to preserve the potential landing
zone of bypass.
Endoluminal, subintimal, and retrograde
approaches in CTOs crossing are key elements of
a successful percutaneous revascularization.
Every center treating CLTI must be familiarized
with these techniques and must have a workload
sufcient to keep the skill of the operators at a
high level.
Endovascular Strategy intheVascular
Territories oftheLower Leg
The concept of target arterial path implies that a
partial revascularization, limited to the arterial
inow or the femoro-popliteal segment, leaving
an untreated diffuse BTK vessel disease, is generally insufcient to obtain healing; a successful
revascularization in CLTI requires restoration of
pulsatile in-line ow to the foot. While in bypass
surgery this is generally an achievable target due
to the size and low resistance of the bypass conduit, in the endovascular treatment of multivessel
diffuse disease this target is more difcult to
obtain. Every segment of the vascular tree of the
inferior limb requires a different and specic
approach.
Treatment ofInow Disease:
TheAortoiliac System
The endovascular treatment of iliac obstructive
disease represents the rst choice of revascularization if done by an experienced team and if it
does not compromise subsequent surgical options.
A recent metanalysis compared endovascular and
open surgical approaches in iliac obstructive disease: the endovascular approach reduced the
length of hospital stay and the postoperative morbidity, while, in the long-term follow- up, open
surgical approach demonstrated a better primary
patency and lower reintervention rate (54).
The procedure must be planned according to
the characteristic of the obstructive lesion: site of
lesion (common or external iliac artery), type of
lesion (stenosis or occlusion), length of lesion,
calcium burden, soft plaque. Whenever possible,
the internal iliac artery should be preserved. The
involvement of common iliac ostium often
requires a bilateral kissing stenting technique, in
order to avoid plaque prolapse and contralateral
ostium stenosis, and to optimize blood ow in the
aortic bifurcation (55–57).
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M. C. Siah et al.
Simple balloon angioplasty is now abandoned
in favor of primary stenting, which represents the
gold standard in iliac treatment, due to better
results in terms of patency and complications
(58–63). Different types of stents are available on
the market: bare metal stents and covered stents,
both in the balloon expandable and selfexpandable conguration. Drug elution has a
marginal role in iliac arteries, limited to restenotic lesions (64).
Balloon expandable stents offer a higher radial
force, able to scaffold calcied lesions, and precise deployment; self-expandable stents have
lower radial force and less precise deployment;
however the adaptable geometry and the higher
exibility facilitate the treatment of longer
lesions and maintain the natural movements of
external iliac artery (65–67).
Covered stents reduce the risk of distal embolization and repair arterial wall ruptures, demonstrating safety and good long-term results in
comparison with uncovered stents (68–71).
Treatment ofInow Disease:
TheCFA
Open endarterectomy is considered the standard
of care for treatment of atherosclerotic stenosis
of the CFA due to the scarce invasiveness of the
procedure, durable results, and possibility to
spare the bifurcation. The endovascular approach
is limited to patients at high surgical risk or with
hostile groin because the CFA is a hyperdynamic
region with risk of stent fracture; obstructive
plaque is often heavily calcied and difcult to
dilate, and in case of bifurcation involvement
stenting can jeopardize the ostium of one main
femoral branch (27).
Nevertheless, there is signicant morbidity
and mortality resulting from open surgery in
CFA, and in recent times the endovascular
approach has demonstrated to compete with surgery. In a recent systematic review and metaanalysis of 28 studies, endovascular treatment
with routine stenting has demonstrated comparable 1-year primary patency and target lesion
revascularization as CFA endarterectomy, with
a lower complication rate (72). Another metanalysis involving more than 3000 patients conrmed these positive 1 year results; however,
after this duration, the patency of the endovascular treatment was signicantly lower than
open repair and the overall rate of stent fracture
was 3.6% (73).
Waiting for further studies, dedicated materials and a broader consensus, endovascular treatment of CFA should be considered in selected
patients with contraindication for surgery and a
favorable anatomy.
Treatment ofFemoro-Popliteal (FP)
Segment
The new GVGs afrm that, “individual lesionbased schemes correlate poorly with effective
revascularization in CLTI, vascular specialists
must integrate approaches for arterial segments
into a management strategy for the whole limb.”
According to this global strategy, complex FP
lesions should be considered for a surgical
approach; however the nal decision relies on the
surgical patient’s risk, type of foot lesion, autologous vein availability, and the evaluation of BTK
and BTA vessel disease.
In the last 20years, the endovascular strategy
for the FP segment is radically improved, with
outcomes approaching that of surgical bypass.
After initial experiences with balloon angioplasty, the introduction of the “drug delivery”
technology, drug coated balloons (DCB) and
drug eluting stents (DES), and covered stents has
signicantly improved the outcomes of the endovascular treatment of the FP segment in terms of
primary patency and freedom from target lesion
revascularization (TLR), becoming the rst treatment option in the FP segment (74–78).
A recent meta-analysis comparing drugcoated devices versus saphenous vein graft
bypass in FP arterial occlusive disease concluded
that there is no signicant difference in shortterm efcacy, short- and long-term mortality
(79). Despite traditional saphenous vein bypass
remaining the gold standard, drug coated devices
provide a reasonable alternative therapy with
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lower short-term morbidity associated with the
procedure (79).
Despite the evolution of materials and techniques, there are still several critical issues
regarding the endovascular treatment of the FP
segment, essentially represented by calcium and
motion.
Heavily calcied lesions are a barrier for every
step of endovascular revascularization: crossing,
dilatation, scaffolding, and drug elution. New
devices are available to overcome calcium resistance to dilatation, starting with high pressure
balloons, cutting and scoring balloons. Orbital
atherectomy has demonstrated to be effective in
modifying the calcied lesions facilitating easier
balloon ination and intravascular drug elution.
A new approach of intravascular lithotripsy to
treat severely calcied lesions in a real-world
study demonstrated low residual stenosis, high
acute gain, and a low rate of complications
despite the complexity of disease. A different
solution is represented by the “pave and crack
technique” which requires stent-graft
implantation and aggressive dilatation of the arterial segment (80).
The second issue is represented by the
dynamic properties of popliteal artery. The whole
FP segment is affected by torsion, compression,
and bending forces during the walking movement
or sitting position. Furthermore, from cadaveric
studies, these forces seem to be lower in the proximal and mid-supercial femoral artery and
higher in the distal portion in the abductor channel and in the popliteal artery (81). Individual
characteristics regarding the muscle modeling,
different for each patient, modify the bending
forces acting on the popliteal artery, and the presence of arterial wall calcication inuences its
curvature. Moreover, the endovascular treatment,
both with angioplasty and stenting, modies the
dynamic characteristics of the FP segment (82).
The choice of the treatment method is a key
point: while angioplasty results in a more exible
artery, suggesting priority to a “leaving nothing
behind” strategy, stents interfere more with FP
dynamic properties (83, 84). Depending on the
anatomical position of the stents, the axial stiffening of the arteries may lead to chronic kinking
and stent fractures, both responsible for restenosis and occlusion and, consequently, affecting the
long-term success of the procedure (82, 85–87).
To overcome these problems, in the last years
different technical approaches have been proposed. Atherectomy, with or without DCB, does
not seem to confer any signicant additional clinical benet compared with balloon angioplasty or
stenting (88–92). However, several authors disagree with this conclusion (93, 94).
A self-expandable nitinol stent (Supera™,
Abbott), with a peculiar geometry that allows
conformability to the FP segment during exion,
showed good results in terms of patency, freedom
from TLR and stent fracture rate (95–99).
Treatment ofBelow theKnee (BTK)
Arteries
BTK arteries are extensively diseased in patients
with CLTI, so to be considered the most challenging eld. The rst line of treatment is plain
old balloon angioplasty with uncoated balloon
with optional bailout stenting. Balloons now are
available in tapered shape and length up to 30cm,
allowing a homogeneous dilatation of the vessel.
Calcication is a common problem in BTK vessels and non-compliant high-pressure balloons,
able to support 25 atm, represent an important
tool in BTK treatment. Cutting, scoring balloons,
and atherectomy could play a role in optimal vessel dilatation. Long dissection after balloon
angioplasty can be corrected by the focal implantation of dedicated stent.
Also in the BTK district, after initial experiences with balloon angioplasty, DESs and DCBs
were proposed in order to improve the outcomes
of the endovascular treatment in terms of primary
patency and freedom from TLR; however the
results were promising but also conicting. The
reasons for this situation of uncertainty are essentially two. First, while studies on FP segment
were predominantly done on claudicants, studies
on BTK vessels were done on patients with CLTI,
resulting in a higher complexity of the clinical
scenario and confounding factors such as wound
severity and comorbidities. Secondly the popula-
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