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334 The infrainguinal arteries: Advice about balloon angioplasty and stent placement
knee joint, a self-expanding stent is appropriately
exible. Woven nitinol stents have unique quali-
ties of exibility and show promise for use in the
distal SFA and popliteal arteries. A standard 12-
or 13-cm length access sheath can be used with
an 80-cm delivery catheter. e more complex
the lesion (e.g., long occlusion, heavily calcied,
extending from SFA to popliteal artery), the more
helpful it is to have a longer sheath that extends
close to the location of the lesion in order to sup-
port crossing and stent delivery. e standard
self-expanding nitinol stent is oversized slightly in
comparison to the reference vessel diameter at the
intended placement site, usually by a millimeter,
but hopefully no more than that. Signicant over-
sizing has been associated with intimal hyperpla-
sia and restenosis. Self-expanding nitinol stents are
deployed from the “tip” end to the “hub” end. e
“tip” end (leading end) of the stent can be deployed
with accuracy and is allowed to are just beyond
the lesion. e delivery catheter for self-expanding
stents typically has a pin-and-pull or ratchet deliv-
ery mechanism. Aer the leading end is deployed,
the delivery catheter is held steady so that the stent
is not abnormally elongated during deployment.
e ratchet or pin-and-pull mechanism removes
a covering membrane that constrains the stent.
Aer uncovering, the stent takes its intended
shape within the artery. Poststent balloon angio-
plasty is routinely performed and oen reveals a
residual waist that is pressing or impinging on the
stent from the outside. Completion arteriography
is performed through the side arm of the sheath.
Standard self-expanding nitinol stents are known
for ease of placement, longer available lengths,
exibility within the artery, and contourability
along the artery. It is possible to crush balloon-
expandable stents with external compression, so
these are generally avoided. Woven nitinol stents
may also be used in the SFA and popliteal arteries.
e advantage is the hoop strength or crush resis-
tance and the exibility. Hence, they are becoming
a preferred stent for heavily calcied segments and
highly exible segments, such as the distal SFA and
popliteal arteries. e stent is not oversized to the
artery but is selected on a one-to-one basis with the
size of the lumen. erefore, the availability of these
stents is in half sizes (e.g., diameters of 4.5 mm,
5.0mm, 5.5 mm, etc.). e artery must be well pre-
pared by creating a lumen adequate for the rings of
the stent to fully form when deployed. is usually
requires aggressive balloon angioplasty prior to
placement, with a balloon that is 0.5–1.0mm larger
than the diameter of the stent. e operator con-
trols the cadence at which the rings or segments of
the stents are deployed. Woven nitinol stents have
excellent results when deployed to the intended
nominal size. e location of the “tip” end may be
adjusted with great accuracy, but the location of
the trailing end (“hub” end) of the stent can be very
challenging to predict. Aer deployment, poststent
placement balloon angioplasty is optional.
DCB angioplasty is discussed in Chapter 20.
Inthe context of SFA and popliteal artery treatment,
there are multiple approved DCBs. It is appropriate
to avoid stenting or scaolding, as far as possible,
in the hope of maintaining long-term patency on
the basis of the medication and avoiding the long-
term chronic inammatory stimulus of an irritating
implant. erefore, the DCB angioplasty technique
is dierent from the standard balloon angioplasty
technique for the supercial femoral and popliteal
arteries, as it is intended to deliver medication and
minimize dissection. If scaolding is required, it
should be performed with the most inert possible
implant and should be performed in a focal manner
so as to avoid a “full metal jacket” approach.
UP-AND-OVER APPROACH TO
THE SUPERFICIAL FEMORAL AND
POPLITEAL ARTERIES
Selective catheterization of the aortic bifurcation
and antegrade passage of a catheter into the con-
tralateral iliac artery are discussed in Chapter 9.
Details of the passage of an up-and-over sheath are
presented in Chapter 14. Equipment required for
an up-and-over approach to infrainguinal inter-
vention is listed in Table 24.3.
Contralateral intervention is performed with an
up-and-over sheath. is permits a stable access
and the ability to perform angiography whenever
required. Keeping the access site remote from the
treatment site permits the operator to isolate these
two variables and helps to avoid a cascade of com-
plications if there is a problem at either the access
site or the treatment site. A challenge to the use of
an up-and-over approach is the presence of a nar-
row, very proximal (well above the usual L4-L5
position), or heavily calcied bifurcation. ese
factors generally resist straightforward placement
of the sheath. One disadvantage of the up-and-over
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Up-and-over approach to the superficial femoral and popliteal arteries 335
approach to infrainguinal treatment is the distance
to the target site. If tibial intervention is included
in the procedure, the distance to the target site may
exceed the available catheter lengths. However,
generally this is a widely applicable technique, a
variety of acceptable sheaths are available, and a
sheath can almost always be placed.
e length of the sheath can be estimated based
on the length of diagnostic catheter required to
reach close to the lesion. Usually, it is best to place
the tip of the sheath as close to the lesion as possible.
Exceptions to this general rule are as follows. If the
lesion is a simple focal stenosis, treatment can be
performed in a straightforward manner without
the extra leverage of having the sheath tip nearby.
If the supercial femoral and/or popliteal arteries
for treatment are smaller in diameter, such that the
sheath may occlude forward ow, the operator has
to take this into account and decide whether this is
best. Additional anticoagulation may be required,
and extra friction will be encountered both dur-
ing insertion and removal of the sheath. Lastly, if
the aortic bifurcation is somewhat hostile to cross,
sometimes the sheath can be a challenge to remove
due to multiple points of friction.
If balloon angioplasty alone is anticipated,
a 4-Fr or 5-Fr sheath is adequate for angioplasty
up to 6 mm in diameter. However, if atherectomy,
stent placement, or other additional maneuvers are
included, even DCB angioplasty, it is better to have
a 6-Fr sheath. is upsizing of the sheath makes the
access insertion site larger, but any additional chal-
lenge posed by this is typically mitigated by use of a
closure device. e limiting factors on sheath cali-
ber are usually the quality of the aortic bifurcation
segments and the quality of the common femoral
artery used for access. Occasionally, one or both of
these will be diseased to the point where upsizing
from a 5-Fr to a 6-Fr sheath is avoided in order to
minimize the risk of a complication. If stent place-
ment is anticipated or it becomes necessary to treat
a postangioplasty complication, a 6-Fr sheath is
required to place a self-expanding stent using a
0.035-inch guidewire system.
If the target treatment site is in the very proxi-
mal SFA, the best way to place the sheath is to
advance the guidewire into the profunda femoris
artery rather than into the SFA. A sti exchange
wire is then exchanged so that the up-and-over
sheath can be advanced into the common femoral
artery just proximal to the lesion. e exchange
guidewire is removed, the wire intended for cross-
ing the lesion advanced, and the sheath used for
angiography to guide the crossing of the lesion.
Table 24.3 Supplies for up-and-over approach to infrainguinal intervention
Length Diameter
Guidewire Starting Bentson 145 cm 0.035 inch
Selective Glidewire
®
150 cm 0.035 inch (steerable)
Glidewire
®
260 cm 0.035 inch (steerable)
Exchange Supra Core
®
180 cm 0.035 inch
Amplatz Super Stiff
®
180 cm 0.035 inch
Catheter Flush/selective Omni
®
Flush 65 cm 4-Fr
Exchange Straight 90 cm 5-Fr
Sheath Selective sheath Up-and-over 45, 55, 70 cm 6-Fr, 7-Fr
Balloon Balloon angioplasty
catheters
Balloon diameter 4, 5, 6 mm
Balloon length 4 cm and longer, up
to 20 cm
Catheter shaft 75, 90, 120 cm
a
Stent Self-expanding Stent diameter 5, 6, 7 mm
Stent length 40–200 mm
Delivery catheter
length
80, 120 cm
a
A 75-cm catheter shaft for balloon angioplasty reaches to mid-SFA in an average sized person. Longer catheters
are required for a contralateral approach to distal SFA, popliteal, and tibial intervention.
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336 The infrainguinal arteries: Advice about balloon angioplasty and stent placement
If the target treatment site is in the distal SFA or
popliteal artery, it is usually best to advance the
initial catheter into the SFA directly and then
place the exchange guidewire in the SFA for sheath
advancement.
Femoral arteriography may be performed
through the side arm of the sheath (Figure 24.3).
If the amount of contrast administration must be
limited, a straight or angle tip catheter may be
passed through the sheath and into the proximal
SFA and an arteriogram obtained in that manner.
e exchange guidewire over which the sheath has
been passed is exchanged for a steerable guidewire,
usually a 260-cm angle tip Glidewire
®
, which is
used to cross simple infrainguinal lesions. A vari-
ety of crossing techniques may be used to cross
more complex lesions, including use of 0.014-
inch or 0.018-inch wires, chronic total occlusion
catheters, or re-entry catheters, and these are cov-
ered in Chapters 20 and 25. Heparin is adminis-
tered: 50–75 U/kg for simple lesions and 100 U/kg
for complex lesions.
e length of the balloon catheter sha is
selected based on the location of the lesion. e
proximal SFA, and possibly the mid-SFA, can be
reached with a 75- or 80-cm length catheter; in a
patient of short stature, it will reach the mid-SFA.
More distal lesions require a 90- or 120-cm cath-
eter. When tibial arteries are approached using
an up-and-over approach, 150-cm length balloon
catheters are available and will reach to the distal
tibial level in the average sized person. An esti-
mate of the required catheter length can be made
using the straight exchange catheter, which is used
to exchange the guidewires. e exchange cath-
eters are usually 65–120 cm in length. Care must
A
D E F
B C
Fig. 24.3 Balloon angioplasty of the femoral and popliteal arteries through an up-and-over approach.
(A) An SFA lesion is identified. (B) A guidewire is introduced through the contralateral femoral artery
and placed over the aortic bifurcation. The guidewire may be placed in either the profunda femoris
artery or the SFA. If the guidewire is placed in the SFA, care should be taken to prevent unintended
encounters between the wire and the lesion during sheath placement. (C) An up-and-over sheath is
placed and arteriography performed. (D) The guidewire is advanced across the lesion. (E) Balloon
angioplasty is performed. (F) Completion arteriography is performed through the sheath.
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Access related issues: Difficult up-and-over approach to the superficial femoral and popliteal arteries 337
be taken to maintain the guidewire in a stationary
position so that its leading edge does not advance
into the distal infrageniculate runo arteries dur-
ing passage of long catheters. Inadvertent wire
advancement can occasionally result in damage
to one of the runo vessels or unguided passage
across a more distal lesion, with resulting damage.
Intermittent uoroscopy is required. It is also usu-
ally helpful to mark the outside location of the wire
and to refer back to it during the procedure.
Aer balloon angioplasty, the catheter is with-
drawn while the guidewire is maintained in place.
Completion arteriography is performed through
the side arm of the sheath. e angioplasty site is
assessed in the same way as described in an earlier
section. Most sel f-expanding stents are del ivered on
catheters that are either 80 cm or 120 cm in length.
e required distance may be estimated based on
the length of the balloon catheter required. Aer
placement of a self-expanding nitinol stent, bal-
loon angioplasty is performed along the length of
the stent followed by completion arteriography.
ACCESS RELATED ISSUES: DIFFICULT
UP-AND-OVER APPROACH TO
THE SUPERFICIAL FEMORAL AND
POPLITEAL ARTERIES
ere are multiple ways in which the up-and-over
access can be challenging. If the infrarenal aorta is
short and the aortic bifurcation is located above the
L4-L5 junction, the angle of the aortic bifurcation
tends to be quite narrow. In addition, if the aortic
bifurcation is highly calcied, the catheter may pass
but a stier exchange wire may not, due to the rigid-
ity of the structures. Lastly, if there is signicant
friction along the path, either from the access site
itself (due to a scarred access vessel) or if there are
numerous untreated lesions in the approach iliac
artery, or if there is signicant tortuosity, all of these
can be problematic and add challenge to the place-
ment of an up-and-over sheath. Catheterization of
the aortic bifurcation is discussed in Chapter 9 and
Figures 9.10–9.12 demonstrate some techniques for
succeeding in this endeavor.
In the following outline, dierent techniques
are discussed that can help resolve the challenging
up-and-over access. ere may be a challenge with
catheter placement in the contralateral iliac artery,
with advancement of an exchange guidewire over
the aortic bifurcation, or with passage of the sheath
over the exchange wire, or with all three of these
important steps.
e up-and-over catheter may be very dicult
to place in some patients. In patients with ipsi-
lateral tortuosity the hook-shaped catheter head
may consistently point to the wrong direction or
it may turn 360 degrees when attempting to point
it toward the contralateral iliac artery. In this case,
the guidewire can be passed into the catheter and
be poised at the tip of the catheter for advance-
ment. e catheter is turned, not so that it points to
the contralateral side directly, but at least so thatit
is not pointing to the ipsilateral side. e wire is
then advanced into the contralateral iliac artery.
A torque device to steer the Glidewire
®
is helpful.
Aer the wire has entered the contralateral iliac
artery, the catheter head is slowly withdrawn while
it is untwisted under uoroscopic visualization.
Two other maneuvers are worth mentioning.
If the catheter consistently assumes the wrong
orientation, the catheter can be advanced further
into the infrarenal aorta. Even as the catheter tip
points toward the ipsilateral side, when the wire is
advanced, it usually bounces o the ipsilateral wall
and goes into the contralateral iliac artery. e
catheter must be rotated until it points to the cor-
rect side. With the catheter being looked at under
uoroscopy, it is rotated slightly to see if the guide-
wire wrap is getting better or worse; this is how to
establish which way the catheter must be rotated.
Another maneuver is as follows. In some patients
it makes sense to advance the hook-shaped or
Omni
®
Flush catheter only to the level of the ipsi-
lateral common iliac artery and then advance the
wire for sha stiness. en advance the catheter
so that the tip itself is leading into the contralateral
side. is is particularly helpful when the infrare-
nal aorta is aneurysmal or has signicant mural
thrombus that must be avoided. Yet another option
is to use a catheter with a tighter curve at the tip,
such as a RIM catheter.
In some patients, aer the guidewire is
advanced, the hook-shaped catheter is unable to
advance over it. In this case it usually means that
the irregularity of the contour of the catheter
where the hook-shaped tip is located is catching on
some calcic plaque. Consider carefully removing
the Omni
®
Flush catheter and advancing a straight
or angled 4-Fr or 5-Fr Glidecath
®
.
If the hook-shaped catheter head goes over the
aortic bifurcation but the wire repeatedly goes
https://t.me/med1917
338 The infrainguinal arteries: Advice about balloon angioplasty and stent placement
into the internal iliac artery or consistently hangs
up on a plaque, consider adjusting the hook shape
as it sits on the bifurcation to point the wire in a
slightly dierent direction. A slight traction on the
catheter usually allows the pointing tip of the cath-
eter to follow the external wall of the iliac artery
(Figure24.4).
In some patients, ipsilateral iliac artery occlu-
sive disease, which the operator may prefer to treat
secondarily, must be treated primarily, because it
is causing a signicant decrease in maneuverabil-
ity or increased resistance to sheath placement.
erefore, the ipsilateral iliac artery occlusive
disease may be treated before contralateral access is
achieved. In this case a sti wire is inserted on the
ipsilateral side, extending into the infrarenal aorta,
and a 6-Fr or 7-Fr sheath advanced retrograde into
the iliac artery. Aer treatment of the iliac artery,
the sheath can then be advanced so that its tip is
in the proximal ipsilateral common iliac artery.
e hook-shaped catheter is then passed through
the sheath and used to cannulate the contralateral
side. e ipsilateral sheath is used as a platform for
cannulation of the aortic bifurcation.
Aer the catheter has been advanced to the
contralateral side, if it is a dicult aortic bifurca-
tion, it is usually best to advance it as far as pos-
sible. It can be advanced into either the SFA and
popliteal artery or into the profunda femoris
artery. Aer that, a sti exchange wire is advanced.
Sti exchange wires may include an Amplatz Super
Sti
®
or a Supra Core
®
guidewire. ese are typi-
cally 0.035-inch diameter guidewires. ey are sti
in the sha but have a variable length of oppy tip
so that the leading wire tip will pass easily through
signicant curvature before the sti part of the
wire arrives. In the usual scenario, the guidewire
advances to the desired location in the contralat-
eral limb so that the sheath can be easily advanced.
In some patients who have a narrow aortic bifur-
cation or a severely calcied bifurcation that is
very sti, the guidewire will not advance because
the anatomy will not relax enough to the shape
that the sti wire is imposing. In this case, con-
sider advancing a sti Glidewire
®
. Sometimes, the
exchange wire will advance more readily if any tor-
tuosity or resistance in the ipsilateral iliac artery
is removed. is can be done by placing a sheath
along the length of the diseased or tortuous ipsilat-
eral iliac artery.
Aer the guidewire is placed, the sheath is
advanced over it. In a situation of dicult access,
it usually makes sense to advance the sheath under
uoroscopic guidance so that if the progress stops,
the location can be identied. is is sometimes a
location that can be dilated with a balloon placed
out ahead of the sheath. Another option with a dif-
cult sheath passage is to use a longer dilator for
the sheath and advance that rst and then tele-
scope the sheath over it. is is demonstrated in
Chapter 14 (Figure 14.8). An example would be to
use a 65-cm dilator for a 45-cm sheath. e dilator
A B C D
Fig. 24.4 Adjusting the up-and-over catheter to obtain the desired trajectory for the wire. (A) A hook-
shaped, Omni
®
Flush-style catheter is used to cannulate the contralateral iliac artery over the aortic
bifurcation. (B) As the catheter is withdrawn to the aortic bifurcation, the shape of the catheter head
changes significantly as it rests on the flow divider. The angle of the curve is much wider at this point.
This angle can be used to direct the guidewire into different trajectories. (C) If a slight amount of
traction is placed on the catheter, the tip of the catheter points toward the outer wall or outer curve
of the iliac artery. (D) If the catheter is advanced slightly and the hook shape is allowed to return to a
little closer to its normal configuration, the tip of the catheter points the wire toward the inner wall or
in a curve of the iliac artery. This can be helpful when the wire immediately encounters a lesion in the
proximal common iliac artery that must be crossed.
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Access related issues: Difficult up-and-over approach to the superficial femoral and popliteal arteries 339
extends well beyond the tip of the sheath. When
the dilator cannot be advanced any further, the
sheath is advanced (telescoped) over the dilator.
Another option is to use a sheath-within-a-
sheath, as demonstrated in Figure 24.5. e sheath
of choice is advanced as far as it can be. Ifthe plat-
form is not adequate, a smaller sheath can be passed
through it and this will usually pass further. In
general, for a sheath-within-a-sheath approach, the
sheath size dierential needs to be 2 Frenchsizes
(i.e., a 5-Fr sheath will go through a 7-Fr sheath
and a 4-Fr sheath will go through a 6-Fr sheath).
Figure24.5 also shows how this is most commonly
used. In patients who require treatment for multi-
level occlusive disease, a 6-Fr or 7-Fr sheath is used
to treat the femoropopliteal segment. If the infra-
geniculate arteries also require treatment, a longer,
lower-prole sheath (4-Fr or 5-Fr) is passed through
A B
C D
Fig. 24.5 Sheath-within-a-sheath to reach more distally. (A) The sheath is passed into a difficult
aortic bifurcation. In this case the tip of the sheath only passed into the proximal contralateral iliac
ar ter y. (B)Because the original sheath would not advance without difficulty, and additional support is
required, a second smaller sheath is passed through the first sheath. In many situations this platform is
adequate for treatment. Sometimes, the original sheath will advance slightly further over the second
sheath in a telescoping fashion if more support is needed. (C) The situation in which a sheath-within-
a-sheath is most commonly used is when a larger sheath is required for iliac artery or SFA treatment,
but additional more distal support is needed to treat smaller runoff vessels. (D) Additional treatment
is required of the tibial arteries. A smaller sheath, usually a 4-Fr or 5-Fr sheath, is advanced through
the original existing platform sheath.
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340 The infrainguinal arteries: Advice about balloon angioplasty and stent placement
the rst sheath to create a better platform for more
distal treatment.
If the sheath of choice will not go over the bifur-
cation or cannot be advanced to the desired loca-
tion, consider using a smaller sheath altogether.
Many dierent types of interventions can be per-
formed using a modied plan and a smaller sheath
than was the operator’s original intent. Another
option is to advance a percutaneous transluminal
angioplasty (PTA) balloon over the wire and ahead
of the sheath. e PTA balloon is inated in a safe
location that is appropriately sized to the balloon
and the structure is used as an anchor over which
to advance the sheath (Figure 24.6). ere is one
other maneuver worth considering but is rarely
required. Obtain a 3 mm or 4 mm diameter bal-
loon, 40–80 mm in length and 0.035-inch diameter
compatible so that it has a 5-Fr sha (Figure24.7).
If the sheath tip stalls on the proximal ipsilat-
eral iliac artery or over the bifurcation, or along
the very contralateral proximal iliac artery, the
lower-prole balloon can be advanced ahead of
the sheath. e balloon is then gently inated to
about 2 atm of pressure. As the balloon is deated
the sheath is advanced over the deating balloon.
is type of inchworm approach can be used to get
the sheath tip past high-risk areas and is relatively
atraumatic.
Lastly, it is better to change the approach, or per-
haps not do the case, than to have an access-related
complication before the intended treatment is even
attempted. Access-related complications for up-
and-over access could include embolization, vessel
rupture, or iliac dissection. Management of these
complications is considered in other sections, but
it is better not to have them. If more than 5 min-
utes have been spent attempting to traverse the
aortic bifurcation, consideration should be given
to selecting an alternative approach.
Strategy: The difficult up-and-over
access
●
Hook-shaped catheter will not point to the
contralateral side: pass the wire then untwist
the catheter; do not attempt to turn the cath-
eter to the perfect direction.
●
Catheter on the bifurcation but wire will not
advance to the correct location: adjust the
hook-shaped catheter to aect the wire trajec-
tory (Figure 24.4).
●
Very narrow aortic bifurcation: use a catheter
with a tighter curve, such as a RIM catheter.
●
Aer cannulation of contralateral iliac artery,
put the wire as far down as possible.
●
Dilate the ipsilateral iliac artery, if needed.
●
Use a longer dilator, then telescope the sheath
over the dilator (see Chapter 14, Figure 14.8).
●
Use a sheath-within-a-sheath if the original
sheath choice will not pass (Figure 24.5)
●
Downsize sheath: if original sheath choice is
not tolerated by the system, sometimes the
A B C
Fig. 24.6 Using an angioplasty balloon to anchor the sheath. (A) A sheath and dilator are advanced over
a difficult aortic bifurcation, but the sheath will not advance beyond the common iliac artery. (B) A P TA
balloon catheter is advanced. The balloon is advanced to a section of normal artery located more dis-
tally, in the distal external iliac artery, the common femoral artery, or the proximal SFA, with the balloon
sized for the chosen anchor location. (C) The balloon is inflated to anchor and stabilize the wire. The
sheath is advanced over the 5-Fr balloon catheter, which has been stabilized by inflating the balloon.
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Tibial artery occlusive disease: Angioplasty and stenting 341
plan can be altered to allow the case to be done
through a one size smaller sheath.
●
Use a PTA balloon to anchor the wire so that
the sheath can be advanced (Figure 24.6).
●
Use a 3- or 4-mm balloon on a 5-Fr sha and
do incremental advancement by advancing
the stalled sheath over the deating balloon
(Figure 24.7).
TIBIAL ARTERY OCCLUSIVE DISEASE:
ANGIOPLASTY AND STENTING
Tibial revascularization is a rapidly growing part
of endovascular practice. Tibial artery disease
causing limb-threatening ischemia may present as
a single level of disease or as multilevel disease that
also involves several inow segments, including the
femoropopliteal arteries. In the case of multilevel
disease, all inow arteries must be treated rst,
either in the same setting or at an interval prior
to tibial artery revascularization. In patients with
rest pain or supercial ulcers, inow treatment is
oen all that is required to manage the patient’s
ischemia, without tibial artery intervention. e
long-term success of most catheter-based tibial
procedures is poor, therefore it is not oen used in
patients with claudication.
Over recent years, a wide variety of tibial
artery pathologies have become manageable with
catheter-based techniques. Occasionally, focal
tibial artery lesions require treatment to amelio-
rate limb-threatening ischemia. In this situation,
A B C
D E
Fig. 24.7 Advancing the sheath over a deflating balloon. (A) A heavily calcified aortic bifurcation
poses a significant challenge to establishing an adequate platform. The guidewire has been placed
across the aortic bifurcation. (B) When the sheath is advanced, the tip of the sheath only goes to the
flow divider and then stops. (C) A balloon catheter is advanced. This is a 3-mm or 4-mm diameter
balloon on a 5-Fr shaft that is compatible with a 0.035-inch diameter guidewire. (D) The balloon is
inflated gently, to approximately 2 atm of pressure. This has the effect of centering the guidewire
and pulling it gently away from the jagged wall of the artery. (E) As the balloon is slowly deflated the
sheath is advanced gently over it in an inchworm fashion.
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342 The infrainguinal arteries: Advice about balloon angioplasty and stent placement
there may be focal lesions in multiple tibial arter-
ies or long lesions in some vessels and focal lesions
aecting single vessel runo. e more common
situation is the presentation of long lesions, up to
25 or 30 cm, and a large proportion of these are
likely to be occlusions. e ability to cross long
tibial artery occlusions has made this a viable
therapy in a large segment of patients who require
revascularization for limb salvage.
Many of the principles, techniques, and devices
required to make tibial procedures a reality have
been adopted from other vascular beds. e best
factors suggesting success are in cases where the
foot damage is minimal and also where the run-
o into the foot is intact. Patients with major foot
damage, exposure of vital structures, or with severe
intrapedal occlusive disease have a lesser chance of
salvage with endovascular approaches. Because
endovascular revascularization rarely provides the
robust level of perfusion that results from bypass to
the tibial arteries, it is oen desirable to open more
than one tibial artery. No matter whether the per-
fusion of the foot is robust or not, the foot should
be managed aggressively to achieve wound heal-
ing. e long-term patency of tibial angioplasty
and stenting may be only fair, but limb salvage is
oen achieved without bypass. Aer revascular-
ization, monitoring of the progress of the wound is
essential since early failure is common. When this
occurs, the opportunity for bypass or repeat endo-
vascular treatment may present itself in a narrow
window during which the wound healing is not
progressing.
Whenever possible, the tip of the sheath is placed
just proximal to the area of treatment. Ideally,
the sheath tip is placed in the popliteal artery so
that minimal contrast can be used and the plat-
form provides good support for the intervention.
A B
C D
E
Fig. 24.8 Balloon angioplasty of the tibial artery. (A) Femoral arteriography is performed. (B) The
guidewire is advanced through a posterior tibial artery stenosis. (C) The angioplasty catheter is
positioned across the lesion. (D) Balloon dilation of the posterior tibial artery is performed. (E) The
balloon is removed and completion arteriography performed.
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Tibial artery occlusive disease: Angioplasty and stenting 343
Balloons range from 1.5 to 4.5 mm in diameter.
Longer low-prole balloons, up to 20 cm or even
30 cm in length, are available for the tibial arter-
ies. e usual platform is 0.014-inch compatible
and some prefer a 0.018-inch platform. An angled
catheter is used to direct the guidewire into the
tibial artery of choice. Aer the wire is across the
lesion, it is best, if possible, to place a balloon that
is long enough to cover the whole lesion with a sin-
gle ination (Figure 24.8). e balloon is inated
slowly until it reaches its full prole and ination
is maintained for a few minutes; 3 minutes is desir-
able. As the balloon expands and the constrict-
ing segments of the lesion give way, the pressure
within the balloon typically decreases and this is
reected in the ination manometer. It is com-
mon to underestimate the true diameter of the
artery since the disease is typically in the medial
layer of the artery and the overall caliber may not
be apparent to the operator on angiography alone.
Some hints of the true vessel caliber may be pres-
ent by observation under plain uoroscopy, as the
A
B C
D E
Fig. 24.9 Tibial artery balloon angioplasty and stenting. (A) A sheath is placed just proximal to the
lesion. (B) A directional catheter is used to help direct the guidewire into the appropriate tibial
ar ter y. (C) A low-profile angioplasty balloon that covers the length of the lesion is placed and inflated.
(D) A significant postangioplasty dissection is present. (E) A stent is placed to treat the dissection.
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