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149
nitrates (vasodilatation). A 21-Gauge needle is used, and a
short radial sheath is inserted to strengthen the radial artery.
A local spasmolytic cocktail (Isosorbide dinitrate, 3 cc, +
Verapamil, 2cc) is injected intraarterial before starting the
navigation.
Retrograde Accesses
Retrograde puncture of a patent artery distal to the lesion
should always be anticipated during installation and draping.
It allows bail-out retrograde recanalization in the case of fail-
Table 16.2 Absolute and relative contraindications for radial access in
femoropopliteal intervention
Patient factors Anatomic factors Procedural factors
– Existing AV stula
or graft
– Prior CABG with
LIMA use
– Anticipated use of
radial artery for AV
stula or CABG
conduit
– Aortic arch
atherothrombosis
– Tall patient
– <0.2–2.5mm
radial diameter
– Vessel
tortuosity
– Radial
occlusion
– Severe
vasospasm
– Negative Allen
test (arch)
– Intolerance to
hyperextended
wrist
positioning
– Devices that
require >7F
sheath
– Devices that
cannot be
provided with
very long shafts
(DES/covered
stents)
– Excessive
distance to target
lesion
– Anticipated
complex
procedure
(calcied CTO)
ure through an anterograde access. A specic paragraph of
this chapter includes these strategies (see “lesion crossing”)
so this paragraph is about retrograde access as a primary and
sole approach in femoropopliteal interventions. The risks of
femoral access and the benets observed with retrograde
approaches as bail-out accesses have encouraged the idea of
performing the endovascular treatment of lower limb lesions
through isolated retrograde approach, namely tibiopedal
arterial minimally invasive retrograde revascularization
(TAMI, Fig.16.5) [24]. It has long been used as a secondline approach when antegrade access has failed [25, 26].
However, retrograde access presents a higher rate of success
than antegrade approach [27]. The CTOP classication
(Fig.16.6) may be helpful to select the best cases for a retrograde approach, the CTOP II and IV, i.e., distal concave cap
(Fig. 16.7), being the most appropriates [28]. Retrograde
revascularizations can be performed through different
accesses such as the distal SFA, the popliteal artery, the proximal anterior tibial artery, the dorsalis pedal artery or the posterior tibial artery. Although distal SFA and popliteal
approaches allow using all sheath sizes for peripheral interventions, our preference goes to pedal accesses. The TAMI
technique was rst described by Mustapha et al. to treat
patients with PAD severely deemed to be at high surgical risk
[24]. This technique may decrease complications related to
femoral access [29]. From an anatomical point of view, it
seems more comfortable to perform the procedures through
a b
Fig. 16.4 Initial steps of a radial access to overcome the issue of challenging common femoral artery access and allow fast ambulation.
Local anesthesia is performed without adrenaline but with nitrate
adjunct (a). The artery is punctured at the wrist with a short (4cm) 21G
micropuncture needle (b and c). A short wire is inserted followed by a
23cm radial sheath (d)
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Fig. 16.5 The technique of
tibiopedal arterial minimally
invasive retrograde
revascularization (TAMI)
intends to perform the whole
procedure through retrograde
access. In the present case,
the posterior tibial artery is
punctured at the ankle, and a
45cm 4 Fr sheath is
introduced up to the level of
the popliteal artery. The
operator can work through the
sheath with an 0.018″ wire
over a support catheter
R. Coscas
Fig. 16.6 The CTOP classication helps to identify the situations
where anterograde or retrograde approach is the most appropriate.
Types 1 and 2 are good indications for intraluminal crossing through an
anterograde access. Types 2 and 4 are good indications for intraluminal
crossing through a retrograde access. The Type 3 conguration is the
most challenging for intraluminal crossing
ef
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151
Fig. 16.7 Illustration of a distal cap (a, b, c; arrows) favorable for
intraluminal retrograde crossing. Note that the proximal cap also looks
favorable for intraluminal crossing (CTOP classication type 2)
the posterior tibial approach because of its straighter course
[30]. The choice of the punctured artery will also relate to the
downstream runoff. An already thrombosed artery will be
preferred whenever possible to limit the risks of thrombosis
at the access site (Fig.16.8). Similarly, in the case of lesions
in the proximal and middle thirds of the punctured artery, the
TAMI technique renders possible the treatment of these
lesions and thus offers complete multi-stage revascularization. The posterior tibial artery puncture, under ultrasound
guidance using a 21 Gauge, has our preference for distal
access. It avoids the two curves encountered (anterior tibial–
pedal junction and proximal anterior tibial artery) when performing a dorsalis pedal puncture. Following arterial
puncture and the insertion of a V18 wire (Boston Scientic),
a 45-cm sheath (Cook) is generally used, or even 70 cm,
which had the advantage to stabilize the access, avoid
multiple passages through a small diameter tibial artery to
minimize vessel injury and perform angiograms closer to the
target lesion. Specic portfolios of 4 Fr devices (Biotronik or
Optimed) are generally used for such procedures. Of note, 5
or 6 Fr sheaths can also be used when necessary. Due to the
small diameter of the arteries, percutaneous closure systems
are not indicated, and all patients receive manual compression for 10min at the end of the procedure followed by a
slight compression bandage.
a bc d
Fig. 16.8 Case of a long supercial femoral artery occlusion without
any proximal stump (a and b). Distally, the posterior tibial artery is
occluded (c) and can be punctured without any risk to damage the
artery. The procedure is performed through a single posterior tibial ret-
rograde access (TAMI technique) using 4 Fr devices. After ballooning
(d), a long dissection is noted, and stenting of the lesion provides a
satisfactory result (e and f)
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R. Coscas
Navigation andStabilization
Following arterial access, heparin is administered intravenously (50 UI/kg), and the navigation phase starts. Its goal
is to bring the distal extremity of a sheath as close as possible to the target lesion. The technical principle is always the
same: (1) navigate down to the lesion using an angiography
the standard wire for a stiffer wire to then be able to bring a
longer kink-resistant reinforced sheath closer to the lesion.
When using anterograde CFA access, a short sheath (generally 11cm length) is enough, and there is no specic navigation or stabilization step except when the lesion is at the
popliteal level, where it may be useful to have a longer
sheath (45cm) to be closer to the target lesion. In FP interventions, the most typical example of navigation and stabilization step is the contralateral retrograde CFA puncture
and crossover. Following short sheath and standard wire
insertion, a double- curved angiography catheter (UF or
RIM) is brought over the wire above the aortic bifurcation.
The contralateral arterial axis is catheterized, and an angiography catheter (the same RIM or UF, or a straighter one in
case of tortuous anatomy) is advanced to provide more support for a wire exchange. An exchange for a stiffer wire is
performed, and the wire is brought as far as possible to the
contralateral side. Recent hybrid guidewires made of a stiff
core and oppy extremity (Advantage, Terumo) allow to
perform the whole step with the same wire. Once the stiffer
wire is in place, the short sheath is removed and exchanged
for a longer kink-resistant reinforced sheath (45, 55, 70 or
90cm length depending on the distance to the target lesion).
The same principles are applied in cases of alternative
accesses using angiography catheter with an adapted curve
to the navigation. For example, when using an upper-limb
access, it is our practice to use a C2 catheter to engage the
descending aorta through the left subclavian artery and then
use a long vertebral catheter (125cm in length) to bring the
wire down to the target lesion.
When bringing a long sheath through the target lesion is
challenging (heavily calcied and/or tortuous vessels),
two tips can be used. The rst one is to inate a balloon at
the distal tip of the sheath sized on the vessel where it is
inated. Then deate fast the balloon and push the sheath
while maintaining the balloon xed. The maneuver is similar to the one used during fenestrated endografts at the
level of the target vessels when aring the stents. A second
tip is to capture the wire distally through a contralateral
retrograde CFA access and obtain a through-and-through
access. This gives an exceptional support to deliver the
long sheath.
Lesion Crossing
Crossing a stenosis is generally a simple step, but crossing a
chronic total occlusion (CTO) can be sometimes extremely
challenging. After bringing a long sheath close to the CTO,
the question will be whether the lesion can be crossed intraluminally or subintimally. Our strategy is to try to cross the
lesion intraluminally as much as possible. This will allow the
optimal use of all further necessary devices, especially atherectomy devices (which are contraindicated for subintimal
use) and drug-coated balloons (DCBs).
Support Catheters
When dealing with CTOs, angiography catheters may not
offer enough support for the wire to cross the lesion. Support
catheters overcome these issues. Straight support catheters
provide more pushability, whereas shaped/angled give more
steerability. Many types and brands of support catheters
exist. Most frequently used in our national market are the
Rubicon (Boston scientic), the CXI (Cook medical), the
Trailblazer (Medtronic) and the Navicross (Terumo). They
are available in 0.014′, 0.018′ and 0.035′. The 0.018′ and
0.014′ support catheters can be used inside a larger 0.035′
angiography catheter or support catheter to even improve the
support. When the lesion is made of several major calcied
plugs, we sometimes change the strategy and use navigating
micro-catheters used for embolizations such as the Progreat
(Terumo) because they are very exible and allow a smooth
navigation between the calcied plugs.
Dedicated Crossing Wires
Specic wires may be necessary when crossing a CTO.We
will not go into the details of the different wires available on
the market, but the reader has to be familiar with the three
main types/features of current wires: crossing wires, navigation wires and support wires. Crossing wires can be useful
when dealing with a CTO.In this setting, the tip load of the
wire is particularly important. We recommend the 0.014′
Halberd (Asahi) wire with its 12 grams tip load or the 0.014
WinnT (Abbott) wire for FP occlusions. Of note, the Halberd
(Asahi) wire is a bit particular in its manipulation. It should
not be torqued at the same time it is advanced. In heavily
calcied lesions, wires with an even more important tip load
may be necessary. It is our practice to use 0.014′ Astato
(Asahi) wires with 20, 30 or even 40 gram tip loads. However,
the greater the tip load, the higher the perforation risk, so it is
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mandatory to be certain to be re-entered in the distal lumen
before starting the vessel preparation.
Subintimal Crossing
When an intraluminal crossing is not possible, a subintimal
crossing is necessary. It is typically done be creating a small
loop on the distal tip in the wire. A small loop generally indicates that the wire is in a quite internal subintimal plane,
whereas a large loop is the sign of a navigation in a very
external plane. Dedicated wires with small loops (Hal Stiff J,
Terumo) exist to favor subintimal crossing in an internal
plane. Crossing the lesion in the subintimal plane is often
easier than in the internal plane, but the issue is then to
re- enter the true lumen distally. This re-entry must be performed in the occluded area or very close after the end of the
CTO to avoid losing major collaterals. It is therefore mandatory to avoid to push the loop of the wire too distal from the
re-entry level. The re-entry is sometimes spontaneous, especially when the subintimal crossing was done in an internal
plane. An angled catheter is advanced over the looping wire,
and the wire is exchanged for a wire with a straight or a
slightly angled distal tip to re-enter the true lumen. When the
re-entry is not spontaneous, two options are available: (1)
use a bail- out retrograde access or (2) use a dedicated reentry catheter. Apart from very specic situations, we prefer
to use a bail- out retrograde access (see dedicated paragraph
below), but re-entry catheters can remain useful when the
operator wants to avoid a distal puncture. These catheters are
all based on the same principles with a retractable needle
(lateral or axial) to perforate the subintimal ap. Many reentry catheters are available. The Outback (Cordis) with a
lateral retractable needle is probably the most popular [31]
and the one with more published data. The Pioneer (Philips)
has the interest to be able to be coupled with intravascular
ultrasound [32].
Dual Access
When an anterograde approach does not allow CTO crossing, our preferred bail-out maneuver is to use a retrograde
access. The goal is to perform a “rendez-vous” with the
anterograde access and have a through-and-through wire
between the two accesses. We already mentioned the different types of accesses in the “Arterial Access” paragraph of
this chapter. Briey, all distal arteries can be punctured. Our
preference is to puncture the posterior tibial artery at the
ankle or the dorsalis pedal artery. But several other arterial
sites can be effectively punctured: the proximal anterior tibial artery, the peroneal artery (more challenging), the popli-
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Fig. 16.9 In the case of anterograde crossing failure, a bail-out retrograde puncture allows to bring a wire over a support catheter in the true
lumen
teal artery and the distal SFA.A 21 Gauge needle is generally
used, and a 0.018″ wire is introduced. Our rst line wires are
the V18 or Victory wires (Boston Scientic). When needed,
a 0.018″ support catheter is used sheathless over the wire
(Fig.16.9). It is useless to introduce a distal sheath for these
bail-out accesses. Once the anterograde and retrograde wires
are in the same space, an angled catheter is brought antegradely to capture the distal wire and obtain the through-andthrough access. Rarely, a snare may be necessary for this
maneuver. Sometimes the two wires are in different planes,
and the rendez-vous is impossible without adjunct maneuvers. In these cases, the rst thing to do is to try to do the
rendez-vous at different levels of the occlusion. If this is not
efcient, it is necessary to add anterograde (reverse-CART
technique), retrograde (CART technique) or dual ballooning
(SAFARI technique) of the occlusion. This will break the
intimal plane and allow the two wires to join each other.
Extra-Arterial Crossing
In rare situations, intraluminal and subintimal crossings can
be felt not appropriate (long stent occlusion, history of many
FP interventions etc.). Techniques of extra-arterial endo-
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bypasses have been described. Exiting the artery, navigating
through the supercial femoral vein and re-entering the arterial lumen is probably the most described alternative [33],
with even specic devices now available [34, 35]. Others
[36] reported the use of the distal profunda femoral artery to
create an FP endo-bypass. We have reported the possibility
to create an extraluminal bypass in the setting of a previous
proximal FP anastomosis [37]. Although the reader has to
know the existence of such procedures, we will not go into
the details of these specic techniques that currently have
few indications.
Vessel Preparation
After crossing the lesion, the step of vessel preparation is
crucial. Its goal is to open the arterial lumen up to the reference vessel diameter to allow the optimal use of antirestenotic therapies.
R. Coscas
Standard Balloon Angioplasty
Prolonged angioplasty with standard balloons (namely plain
old balloon angioplasty, POBA) is the reference method for
vessel preparation [38, 39]. It is also the simplest and the less
costly. We prefer to use long balloons sized 1:1in diameter
compared to the reference vessel diameter and 10mm longer
than the target lesion to avoid a geographic miss. A vessel
preparation of 180s vs. 30s improves the immediate results
of angioplasty [39]. It decreases the major and minor dissection rates and the need for additional treatments (re- dilatation,
over-dilatation and stents) [39]. Horie etal. have shown that
each supplemental minute of dilatation is independently
associated with a decrease in the rate of severe dissections
[38]. High-pressure non-compliant balloons such as the
Conquest balloon (Becton, Dickinson and Company) can
deliver a localized pressure up to 40 atmospheres and are
therefore useful to open refractory lesions (myointimal
hyperplasia, calcications).
Cutting andScoring Balloons
Scoring balloons intend to address the limitations of conventional angioplasty balloons by concentrating the dilating
force along the scoring element. They allow a controlled and
uniform expansion of the balloon and nitinol cage, preventing slippage while scoring the plaque and maximizing luminal expansion. Their main indications are challenging lesions
at high risk of dissection post-angioplasty, especially calcied lesions. Main specic angioplasty balloons are the
Angiosculpt (Philips), the Ultrascore (Becton, Dickinson
Fig. 16.10 Angioplasty of a calcied lesion using the scoring balloon
Angiosculpt (Philips). The helical nitinol scoring elements are visible
under uoroscopy
and Company), the Chocolate (Medtronic) and the Cutting
(Boston Scientic) balloons. The two last ones may be better
dened as atherectomy devices. They have common features
in their use: no oversizing, slow ination, long ination time,
repeat inations, low deation. The Angiosculpt (Philips) is
a nylon balloon surrounded by an external nitinol-based helical scoring edge [40]. It has three to four rectangular lasercut nitinol electropolished spiral struts in a helical
conguration (Fig. 16.10). It is generally recommended to
slightly undersize the balloon by 0.5 mm compared to the
reference vessel diameter to avoid major trauma. In a specic registry [40], the presence of calcications had no more
impact on patency following the use of the Angiosculpt
(Philips) balloon.
Debulking Devices
The concept of debulking devices is to remove plaque fragments from the lumen. All these systems need to be used
intraluminally. They are contraindicated when the lesion has
been crossed subintimally. There are ve main concepts:
rotational atherectomy (Jetstream, Boston Scientic), orbital
atherectomy (Diamondback, Cardiovascular Systems/
Abbott), directional atherectomy (HawkOne, Medtronic),
hybrid atherectomy (Phoenix, Philips) and the laser atherectomy (Excimer, Philips).
Depending on the systems, larger sheaths (7 or 8 Fr) may
be necessary. Debulking devices have been shown to effec-
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Fig. 16.11 This very calcied lesion of the distal supercial femoral
artery (a) is crossed intraluminally, and a lithotripsy balloon is used for
the vessel preparation. The lithotripsy emitters are well visible before
tively reduce the rate of intraoperative dissections, decrease
the rate of stent placement and improve technical success
[41]. These devices are, however, not able by themselves to
increase primary patency and decrease target lesion revascularization rates [41]. An additional anti-restenotic therapy
must always be considered. Several drawbacks of debulking
devices have to be mentioned: increased procedure length,
multiple angiograms (contrast media, radiations) and active
friction against the plaque, with subsequent risks of emboli
and low ow that mandate the use of lters with some systems. Our practice is to use debulking devices for long and
complex FP lesions, in-stent restenosis [42] or specic
situations where the wire crosses the lesion but nothing
passes over the wire.
Intravascular Lithotripsy
This preparation tool is dedicated to calcied lesions. The
concept of intravascular lithotripsy (IVL) is to bring an endovascular balloon with lithotripsy emitters at the level of the
target lesion, inate the balloon at low pressure (4 ATM) and
then emit sonic waves that create microfractures in the calcied plaque. This has the goal to open the lumen, modify the
compliance of the vessel and create channels where local
drugs (paclitaxel or limus) will be able to reach the vessel
wall. The main balloon in this eld in currently the
Shockwave (Shockwave Medical). Current balloons are
short (30–60mm long), but all diameters for peripheral use
are available (from 2.5 to 12mm). IVL can be used intraluminal but also subintimal. In the prospective randomized
Disrupt PAD III study [43] and in a meta-analysis [44], IVL
ination (b). The lithotripsy is performed using an “overlap” strategy to
treat the whole lesion (c and d). Due to recoil, an interwoven stent is
implanted with a good result (e)
allows to decrease the rate of severe dissections and bail-out
stent rates after angioplasty, which is particularly useful
when a drug-coated balloon strategy is planned. It is however
also useful as a preparation tool before stent placement since
the immediate luminal gain is superior to the one of standard
angioplasty (Fig.16.11). This technology is particularly safe
with very few descriptions of peripheral emboli and lowow phenomena [45].
Anti-Restenotic Therapy
Vessel opening by itself does not provide durable results in
the FP area. Additional local anti-restenotic therapy will
increase primary patency and avoid target lesion revascularization. Bare-metal stents (BMS), drug-eluting stents, covered stents (CS) and drug-coated balloons are the main
current anti-restenotic devices. The reader should note that
few comparisons between the different concepts of antirestenotic therapy have been performed. Our current algorithm regarding the anti-restenotic strategy is provided in
Fig.16.12.
Bare-Metal Stents
The oldest anti-restenotic therapy is bare-metal stent (BMS)
placement. BMS has the goal to reline any intraoperative
dissection and avoid restenosis by scaffolding the target
lesion. Since the FP segment is highly mobile, BMS used
must be able to follow arterial deformations and have a
memory shape. Current BMSs for FP interventions are in
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Fig. 16.12 Our current
algorithm regarding
anti-restenotic therapies
during femoropopliteal
interventions
R. Coscas
nitinol (Nickel Titanium Naval Ordinance Laboratory), a
hyperelastic alloy that has good resistance to fatigue and
deformation with a low elasticity modulus (100GPa). These
stents are self-expandable and delivered through a retractable sheath. Most nitinol BMSs are made by laser cut of a
fully metallic tube. The metallic mesh varies from one stent
to another, and a distinction is generally made between open
and closed-cell stents (cells < or>to 5mm2 after deployment). The last generation of nitinol stent has to be mentioned: vascular mimetic implants. The main one is currently
the Supera stent (Abbott). Its specic interwoven design
creates a high exibility and resistance to external crush,
with low chronic outward force [46].
Several prospective randomized studies have demonstrated the superiority of BMS over standard angioplasty
[47, 48] in terms of primary patency and target lesion revascularization. Mid-term and late in-stent restenosis as a result
of intimal hyperplasia (IH) remain the major issues with all
current BMSs. This is particularly true when the stenting
length increases [49]. The main problem with IH is that it is
more challenging to treat than a primary stenosis made of
atheroma. IH is less sensitive to angioplasty, and most efcient way to treat it is to debulk the in-stent material with a
specic device. All devices described below should be perceived as evolutions of BMSs with the goal of limiting IH
development.
Drug-Eluting Stents
Drug-eluting stents (DES) are nitinol stents covered of an
anti-proliferative agent whose goal is to limit vascular
smooth muscle cells and broblast proliferations to avoid
IH.Nowadays, two main DES are available for FP interventions, both delivering local paclitaxel (PTX) in an amorphous
form. The Zilver-PTX stent (Cook, Bloomington, IN) is
directly embedded with PTX (3μg/mm2) without excipient.
The Eluvia stent (Boston scientic) intends to provide long,
low-dose PTX delivery (0.167 μg/mm2) using a specic
polymer for coating. Current evidence seems in favor of the
Eluvia stent. The prospective randomized IMPERIAL trial
[50, 51] demonstrated superior rates of PP at 12months with
the Eluvia stent compared with the Zilver-PTX stent (86.8%
vs. 81.5%; p < 0.0001). The EMINENT trial [52] demonstrated the superiority of the Eluvia stent over BMS in lesions
comprised between 30 and 210mm long (primary patency at
12months of 83.2% vs. 74.3%; p < 0.01). In contrast, the
BATTLE trial [53] could not show any benet of the ZilverPTX over BMS at 12months in terms of in-stent restenosis
rate.
Covered Stents
In covered stents (CS), the metallic mesh of the nitinol stent
is covered with polytetrauoroethylene (PTFE) to avoid IH
between the stent struts. Therefore, CS avoid in-stent IH but
not edge-stent stenosis related to undersizing, infolding,
compliance mismatch or atheroma evolution. The main CS
for FP intervention is the Viabahn (W.L.Gore) with heparin
bounding. It combines the advantages of a high exibility
with a good resistance to external crush. Some Viabahn
stents are now available over an 0.018′ platform and allow
working in a 6 Fr sheath for 6mm diameter stents. Sizing of
the stent is paramount, and the Viper trial [54] has shown that
moderate oversizing (≤20%) provides better patency rates
than important oversizing (>20%). Data with CS are particularly interesting in lesions >200mm in length. In the prospective randomized Viastar trial [55, 56], the 24-month
patency rates in lesions >200mm were 65.2% versus 26.7%
(log rank p=0.004), and freedom from TLR was 80.0% vs.
61.9% (log rank p=0.13) in favor of the Viabahn stent versus BMS (Fig.16.13). However, in our experience, we tend
to use less CS since we noted that failure of CS present more
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Fig. 16.13 In this long
supercial femoral artery
occlusion (a), the vessel
preparation with a standard
balloon does not provide a
satisfactory result (b). A long
covered stent (Viabahn; Gore)
is implanted (c) and still
patent at 3years (d)
a bcd
Drug-Coated Balloons
Fig. 16.14 A long covered stent (Viabahn; Gore) was implanted out-
side of the instructions for use, in a popliteal artery occlusion (a and b).
It occluded several months after implantation with a more extensive
thrombosis and acute presentation (c)
with acute extensive thrombosis and severe clinical presentations (Fig.16.14), while BMS present with more progressive
well-tolerated restenosis. This may be related to re-entry collaterals coverage with CS, but the precise mechanisms need
to be investigated.
Drug-coated balloons (DCBs) represent an alternative antirestenotic therapy without the implantation of a denitive
scaffold. These balloons are not made for angioplasty and
vessel opening. They work as a carrier that deposit the antirestenotic drug in the vessel wall to avoid restenosis. An
excipient is used to attach the drug to the balloon. Nearly all
current DCBs use paclitaxel in a crystalline form, but some
new-generation DCBs are now coated with limus. Doses of
paclitaxel are different between the balloons, and it is usual
to distinguish low-dose DCBs (2μg/mm2) from high-dose
DCBs (>2μg/mm2). Before DCB use, perfect vessel preparation is mandatory. The goal is to have a lumen wide open
(<30% residual stenosis) without ow-limiting dissection.
After meticulous preparation, the DCB is brought and
inated at the level of the lesion. It is paramount to size the
DCB to the vessel diameter to allow the drug to penetrate the
vessel wall and avoid any geographic miss by using a DCB
longer than the target lesion. The transit time between the
sheath valve and the target lesion should be as short as possible to avoid drug dispersion in the bloodstream. The DCB
is then inated for a prolonged time (generally 3 min) to
depose the drug. Many prospective randomized trials have
now demonstrated that DCBs are superior to uncoated balloons for primary patency and target lesion revascularization
when used at the level of the FP segment at 12 [57–60] and
24 [61, 62] months. Data at 5years have even been published
with the In.Pact (Medtronic) balloon [63], showing sustained
benet with such devices, although the effect is progressively lost in the long term. It should be underlined that when
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R. Coscas
Fig. 16.15 Intraoperative view with an IVUS probe. It can be coupled with duplex to allow a better understanding of the situation
treating long lesions with a DCB strategy, bail-out stenting,
generally using short stents, is frequent in up to 40% of the
patients in lesions with a length>150mm [64]. Micro- emboli
of crystalline PTX could be a concern [65], but its clinical
relevance is debatable.
Intraoperative Imaging
Intraoperative imaging is nowadays more perceived as a key
aspect of FP interventions. Many operators still rely on intraoperative uoroscopic/angiographic parameters to estimate
the path taken by the guidewire (intraluminal or subintimal),
assess the result of the vessel preparation, take the decision
to stent or not to stent, and conclude on the nal result of the
procedure. Several recent tools have emerged to improve the
value of intraoperative imaging. To better understand the
path taken by the wire, fusion imaging may be helpful [66].
For vessel preparation and assess the nal result of the procedure, angiographic assessment is based on the aspect of
the treated segment (dissected or not), the estimation of
residual stenosis (>30% being considered satisfactory) and
the subjective ow washing. Our practice is to use at least
two incidences and to assess the nal aspect of the repair
without the wire in place. When there is a risk of early recoil,
several operators have the use to perform an angiography
5–15 min after the completion angiography. However, a
major advance in intraoperative imaging is probably the
advent of intravascular ultrasound (IVUS, Philips). The
IVUS probe is advanced over a 0.014″ wire and can be coupled with duplex assessment (Fig.16.15). Recent American
Medicare data have shown that IVUS use during peripheral
arterial intervention was associated with a lower risk of
major adverse limb events during follow-up [67]. Optical
coherence tomography (OCT) may represent an alternative
in the future [68], but this needs to be proved by more robust
data.
Access Closure
The nal aspect of the procedure is access closure. It can be
done using manual compression (MC) or the insertion of a
vascular closure device (VCD). Going into the technical
details of current VCD is outside the scope of this chapter;
we here just focus on general concerns. Same-day discharge
procedures have highlighted the need for fast ambulation and
decreased access bleeding complications. It is our practice to
do a low-dose protamine administration (half the heparin
dose) to decrease local bleeding [69]. When working with a
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