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205
18
More about balloon angioplasty:
Keeping out of trouble
KEEPING OUT OF TROUBLE IS
SIMPLER THAN GETTING OUT OF
TROUBLE
ere are numerous ways to get into trouble dur-
ing the course of a balloon angioplasty procedure.
Appropriate patient selection and lesion selec-
tion remain the two most important factors in
preventing problems. However, premature loss of
guidewire access, overdilation of a lesion, throm-
bus generation caused by inadequate ushing or
lengthy catheter times, and many other avoid-
able problems may occur. e best way to ensure
success is to treat endovascular operations with
the same selectivity, preparation, and methodi-
cal approach that is required for open operations.
Balloon angioplasty may also help prevent or man-
age problems. It serves as a valuable adjunct to all
other reconstructive procedures and will remain a
useful tool for the forseeable future.
WHAT IS THE STRATEGY FOR
MANAGING MULTIPLE LESIONS?
When contemplating angioplasty for multiple
sequential lesions, it is important to remember
that the long-term success rate of the procedure
decreases with each additional angioplasty site.
is is especially true when there are several lesions
in a series in the same conduit, such as a single iliac
artery or supercial femoral artery (SFA).
When multiple sequential lesions require dila-
tion, angioplasty usually proceeds from proximal
to distal, even if the proximal lesion is less stenotic
(Figure 18.1). e iliac lesion that poses an inow
decrement to a diseased SFA is usually treated rst,
and once a satisfactory result has been obtained,
the infrainguinal arteries are treated. Dilation
of a distal critical lesion is most likely to remain
uncomplicated if there is adequate inow to the
area when the balloon is deated. It is usually safest
to dilate each lesion separately and to avoid angio-
plasty where it is not required between lesions.
Sequential ipsilateral lesions that occur in dif-
ferent arteries (e.g., the ipsilateral iliac artery and
SFA) are managed with angioplasty of the inow
artery rst. Success rates aer dilation of the proxi-
mal (larger) artery are superior to that of the dis-
tal artery in most settings. e best approach is
to assess the results of iliac angioplasty rst and
proceed with further angioplasty aer the proxi-
mal lesion has been adequately treated. When
critical limb ischemia is being treated and there
is signicant tibial occlusive disease, it is usually
best to treat femoropopliteal disease aggressively to
ensure inow to the level of the knee.
When multiple sequential signicant stenoses
occur in the same conduit artery (e.g., the SFA)
without any signicant branches between the
stenoses, all the lesions should undergo angio-
plasty if any dilation is performed. Angioplasty
of only some of the lesions changes the anatomy
but yields no hemodynamic improvement, and the
lone angioplasty site(s) may thrombose because
of continued low ow aer dilation. One pos-
sible exception to this is when a critical lesion is
located in the middle of an arterial segment that
is diusely diseased but is composed of only mild
stenoses (Figure 18.1). In this case, it may be bet-
ter to dilate the single critical area only and then
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206 More about balloon angioplasty: Keeping out of trouble
assess the results. e guidewire should be placed
across the entire arterial segment in case exten-
sive dissection occurs. An exception to the proxi-
mal to distal approach is when a distal lesion is so
tight that the balloon is placed in that one rst,
since the balloon has the lowest prole prior to its
rst ination. In other words, once the balloon is
inated to treat another lesion, the prole of the
balloon may be such that it will not subsequently
cross the very tight lesion. When a single conduit
artery is being treated, such as the femoropopliteal
segment, but there are multiple lesions, the bal-
loon is placed distally rst and then moved proxi-
mally. e whole artery must be treated, and best
balloon performance is to begin distally and move
more proximally.
A
B
C D
Fig. 18.1 Strategy for angioplasty of multiple lesions. When multiple levels of disease are being
treated (e.g., iliac and SFA) in the same session, the usual approach is to treat the proximal lesion first
and then the distal lesion. If there are multiple lesions in the same conduit artery, the approach may
be proximal to distal or distal to proximal, depending on the circumstances. (A) When multiple lesions
are in the same conduit artery, and one or more of them require dilation, all the lesions are treated.
Treat proximal to distal when the balloon size is the same for all lesions and especially if the lesions
are focal. (B) When sequential lesions are in different arteries, the proximal lesion is dilated first.
Inflow should be established prior to proceeding to the next more distal target vessel. The proximal
portion of the treatment may be done with the guidewire across the distal lesion, but it does not have
to be across the distal lesion to treat the proximal lesion. (C) When a diffusely diseased artery with
a significant plaque burden requires treatment, the operator has to decide how “perfect” a result
is desired or even possible. Sometimes in this setting, it makes sense to consider dilating only the
critical areas of stenosis. (D) If there is a long segment of disease and the balloon must be at its low-
est profile to be pushable across a long lesion, it is best to pass the balloon as far into the lesion as
possible and initiate angioplasty at the distal end of the lesion. After the balloon wings have created a
higher profile for the device, it will be easier to withdraw the balloon than it will be to advance it.
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Which lesions should be predilated? 207
Complications are avoided if lesions are dilated
on the basis of clinical problem solving rather than
the appearance of the lesions.
Technique: Keeping track of the tip
of the sheath
During the angioplasty procedure, a common con-
cern is keeping track of the location of the tip of the
sheath (Figure 18.2). Placement of the sheath too
far wit hin the arter y may unintentionally dotter t he
lesion. Balloon ination within the sheath tip may
damage the tip causing it to require exchange and
risking damage to the artery when it is removed.
e location of the sheath tip should be conrmed
prior to ination. When a stent is placed, it is also
useful to be sure that the stent placement clears the
end of the sheath.
1. When working room between the sheath tip
and the lesion is minimal, the sheath must
occasionally be withdrawn partially to make
way for the inated balloon.
2. Many dierent types of sheaths are currently
available with a radiopaque marker in the tip.
is simplies the procedure and makes it
more ecient. Routine use of sheaths with a
radiopaque marker in the tip is recommended,
especially in situations where the working
room is short.
3. A magnied view of the area of the sheath
may also visualize the end of the sheath along
the guidewire where the prole of the wire
changes.
4. Filling the sheath with contrast through its side
arm may also be helpful.
5. If the balloon catheter ts snugly within the
sheath, the operator can usually sense when
the balloon portion of the catheter is passing
through the tip of the sheath because of the
change in the friction applied to the catheter at
this point. is location can be identied using
uoroscopy.
WHICH LESIONS SHOULD BE
PREDILATED?
e use of predilation has changed signicantly
in recent years. Predilation may be used as ves-
sel preparation prior to a drug-coated balloon, a
stent or a covered stent, or other denitive ther-
apy. Balloon angioplasty as a stand-alone method
of reconstruction is decreasing in importance in
most vascular beds. One exception is the tibial
and pedal circulation, where balloon angioplasty
remains the primary therapy. Predilation may be
performed to create an adequate lumen to place
the device selected for denitive treatment, such
as a renal, visceral, or carotid stent, which may
not pass into the artery unless space has been cre-
ated. Predilation may also be used to prepare the
artery for a drug-coated balloon. In this case, the
response of the vessel to the angioplasty mecha-
nism helps the operator to determine denitive
therapy, since a severe dissection aer predilation
would probably rule out use of a drug-coated bal-
loon in that setting. e cost and speed of predi-
lation and immediate feedback of vessel lumen
and appearance with digital imaging makes this
step helpful as a part of many dierent strategies.
A B C
Fig. 18.2 How do you know where the tip of the
sheath is located? Losing track of the sheath tip
is a common mistake that leads to problems.
(A)Routine use of a radiopaque sheath tip is the
best way to keep track of the sheath location.
(B)Contrast puffed from the tip of the sheath
is also useful. (C ) A magnified view often helps
identify the outline of the sheath where the
“shadow” of the tip of the sheath is much larger
than the wire. (D) After balloon angioplasty, the
balloon on the end of the angioplasty catheter
usually is met with some resistance as it is pulled
into the sheath. The balloon location as observed
fluoroscopically identifies the location of the
sheath tip.
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208 More about balloon angioplasty: Keeping out of trouble
Predilation can be performed with angioplasty
balloons on each of the dierent wire systems (i.e.,
0.014-, 0.018-, and 0.035-inch). If a preocclusive
stenosis cannot be crossed with an appropriately
sized balloon because of the high prole of the
catheter, a lower-prole balloon is required to pass
through the lesion. e balloon catheter should
not be kept in the lumen for longer than necessary
since the potential for thrombosis at the angio-
plasty site is high. Care should be taken to ensure
adequate anticoagulation since once the ow has
been restored, a slow ow situation may encourage
fresh thrombus formation. If a stent is required, but
the minimal remaining lumen prevents passage of
the appropriate sheath or stent delivery catheter,
predilation is required. It is sometimes useful to
perform predilation of heavily calcied but criti-
cally stenotic arteries to assess how the lesion will
respond to angioplasty. When the correct balloon
size is not clear based on arteriography, predilation
with a smaller balloon is reasonable in order to
assess more accurately the diameter of the artery.
In performing predilation, to the extent possible,
use a balloon that covers the length of the lesion.
If the lesion is too long for a single balloon, use the
longest balloon available of the appropriate cali-
ber. If in passing the predilation balloon through a
long lesion, such as in the lower extremity, the for-
ward motion of the balloon stalls due to friction,
it is usually best to initiate angioplasty of as much
of the lesion as possible. Even though the balloon
wings are higher in prole aer rst ination,
the balloon usually advances because the friction
between the angioplasty balloon and the lesion is
decreased.
WHICH LESIONS ARE MOST LIKELY
TO EMBOLIZE?
Embolization of particulate matter released from
plaque is likely to occur with each angioplasty.
Fortunately, embolization of clinical importance is
not common. It seems to occur sporadically and
is usually not predictable. When it does occur,
however, it can be devastating. e incidence of
embolization is minimized with appropriate anti-
coagulation, cautious passage of endovascular
devices, and minimal manipulation of the lesion
prior to denitive therapy. Some lesions pose a
higher risk of embolization, including those that
present with embolization, occlusions, lesions that
are highly irregular or ulcerated, lesions that have
fresh thrombus associated with them, lesions that
are aneurysmal, and complex lesions located in
the infrarenal abdominal aorta or the innominate
artery. Carotid bifurcation lesions are oen friable,
may contain hemorrhage within the plaque, and
have a high risk of embolization. Use of some
method of cerebral protection in this setting is
routine. Occluded stents have a higher risk of
embolization on recanalization than many other
types of lesion.
If the risk of embolization is high and endovas-
cular treatment of the lesion is most appropriate,
consider some type of distal protection. Primary
stent placement or even placement of a covered
stent may also be considered. Use very complete
systemic anticoagulation when treating a poten-
tially embologenic lesion. If the operator is con-
cerned about the possibility of embolization, the
runo from the target lesion should be evaluated
prior to and aer the treatment.
WHAT ABOUT POSTANGIOPLASTY
DISSECTION?
Balloon angioplasty causes dissection. e lumen
gain achieved by the angioplasty mechanism is
almost entirely by plaque disruption. orough
arteriographic inspection of a balloon angioplasty
site usually reveals some evidence of dissection.
Oblique views sometimes will show additional
dissection, which can be seen on the initial post-
angioplasty angiogram. IVUS usually identies
dissections more readily. Dissections may occur
aer balloon angioplasty of any artery. e occur-
rence of a severe dissection is unpredictable, and
therefore the postangioplasty result must be evalu-
ated in each case. It is impossible to know which
dissections require treatment. In clinical treat-
ment situations in which stent placement is always
or almost always performed, such as at the carotid
bifurcation, the subclavian artery origin, or the
renal artery origin, whether or not a severe dissec-
tion has occurred is less important, since a stent
will be placed in any event. However, in situa-
tions where a stent is not mandatory or in which
a drug-coated balloon might be used, the occur-
rence, severity, and distribution of dissections are
important. is situation might be encountered
aer balloon angioplasty in the common femo-
ral, supercial femoral, popliteal, or tibial vessels.
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What about postangioplasty dissection? 209
It might also be encountered in a mid-subclavian,
axillary, brachial, or forearm artery lesion or a
mid-renal artery lesion or visceral artery lesion.
Knowing which dissections require treatment with
scaolding is not possible. Untreated dissections
may cause target lesion thrombosis or provide a
nidus for restenosis. ere is a lot of discussion
about the need to treat “ow limiting” dissections,
but to date this situation has not been dened. Flow
limitation is being measured using very qualitative
methods, typically with observation of ow on
angiography. Pressure across a dissected segment
can also be measured, but the correct threshold for
treatment is not known. Dissections may also be
somewhat dynamic, and the value of this measure-
ment while the patient is at rest may be limited.
Most of the time dissections are graded using a
system that was intended for the coronary arteries.
A better system is required.
ere are some ideas about how to minimize
the amount or severity of dissection during angio-
plasty. A slow ination over a period of about
30seconds, ination of the balloon only until the
waist on the balloon opens fully and the balloon
is eaced, and then keeping the balloon inated
for 2–3 minutes, might decrease the incidence of
severe dissections.
Dissections tend to occur at branch points, in
juxtaposition to very bulky or circumferential
plaques, and in arteries with diuse longitudi-
nal plaque formation without natural cleavage
planes, especially if the plaque is heavily calci-
ed. e external iliac artery, especially near its
origin, and the SFA, especially at its origin and in
the adductor canal, tend to dissect (Figure 18.3).
Long lesions and occlusions of the SFA frequently
produce dissection aer angioplasty. e popli-
teal artery has numerous perigenicular branches.
When a popliteal artery lesion is diuse, angio-
plasty oen results in dissection. Treatment of the
tibial artery origins are also more likely to result
in dissection. e aortic bifurcation, the common
carotid artery, and the subclavian artery also share
this propensity for dissection, although primary
stent placement during treatment of these arteries
is more common. Dissection may also occur as a
result of inadvertent overdilation of any artery.
Although dissection has been one of the feared
complications of angioplasty in the past, the devel-
opment of intravascular stents has made it possible
to successfully treat postangioplasty dissection
A
B C
D E F
Fig. 18.3 Arterial dissection after balloon
angioplasty. (A) A common iliac artery lesion
extends into the proximal external iliac artery.
(B) Balloon dilation is performed across the iliac
bifurcation. The balloon may be oversized for
the proximal external iliac artery, especially if
the location of the bifurcation is not completely
clear or if the size differential between the
common and external iliac arteries is not appreci-
ated. A contralateral anterior oblique projection
should be used for angioplasty of this segment.
(C) A postangioplasty dissection occurs that
involves the distal common iliac artery and the
proximal external iliac artery. Stent placement
is performed fairly routinely in the iliac arteries,
especially after a dissection. (D) An SFA stenosis
is identified in the adductor canal. (E) Balloon
angioplasty is performed through an ipsilateral
antegrade femoral artery approach. (F) A sig-
nificant dissection occurs at the angioplasty site.
Adissection flap impedes flow in the lumen and
some contrast is trapped in the wall of the artery
by the dissection.
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210 More about balloon angioplasty: Keeping out of trouble
when it is recognized on the angiographic table.
Nevertheless, it adds cost and needless excitement
and, if dissection is not recognized or occurs at a
later interval, it may cause acute failure of the pro-
cedure. Another benet of stent availability is that
a broader array of complex lesions may be consid-
ered for angioplasty, since a treatment option is
available if the lesion is not adequately treated or
iseven worse aer balloon angioplasty alone. is
is discussed in greater detail in Chapter 19.
A dissection may be recognized aer balloon
angioplasty by the appearance of parallel, wavy
lines in the ow stream. ese are elevated sheets
of tissue or plaque. Contrast that remains trapped
in the wall aer the main bolus of contrast has
passed is a sign of severe dissection. Flow in the
artery may stop if the ap is pressed up against an
opposing wall by oncoming inow.
WHEN TO USE KISSING BALLOONS
(
FIGURE 18.4)
e real issue is about when to be concerned that
angioplasty in one artery can cause the poten-
tial for embolization or plaque shi or damage
to another artery. is typically occurs at major
branch points. If kissing balloons are not used
in this setting, the operator might consider plac-
ing a guidewire in the branch that it is intended
to protect if plaque shi does occur. Places where
this might occur include the aortic bifurcation,
the femoral bifurcation, the tibioperoneal trunk
bifurcation, and the bifurcation of the innominate
artery. If there is truly a bifurcation lesion that
extends equally into both branches, kissing bal-
loons should be used. If the plaque is limited to
just one side, but is very close to the origin of the
juxtaposed branch, then a guidewire placed in the
branch is a good way of being prepared for a prob-
lem if one occurs.
PAIN DURING BALLOON
ANGIOPLASTY
Discomfort is common at the angioplasty site
during balloon ination. is usually indicates
stretching of the adventitia. When pain occurs,
it is usually a sign that the balloon has reached
its maximal allowable diameter. It is usually best
to avoid pushing the pressure in the balloon any
higher. Deation of the balloon should be followed
by a quick resolution of discomfort. If pain contin-
ues, it could represent rupture or dissection. ese
possibilities should be immediately ruled out with
completion arteriography. e management of
arterial rupture is discussed later in this chapter.
Pain that occurs during aortic or iliac angio-
plasty is worrying, since a rupture in this location
may result in retroperitoneal hemorrhage. It is
usually best to deate the balloon and check an
immediate angiogram if the pain is severe. Pain
that occurs during femoral or popliteal angio-
plasty is more common and is less worrying and
should not prevent keeping the balloon inated for
as long as the operator believes is indicated, as long
as the pain can be managed. Pain during tibial or
pedal angioplasty is a little bit less common and is
A
C D E
B
Fig. 18.4 When to use kissing balloons.
(A)Aproximal SFA lesion is being prepared for
treatment. (B) Because of the proximity to the
profunda femoris artery, a guidewire is placed
in the profunda femoris artery as the proximal
SFA lesion is being treated. (C) A lesion at the
bifurcation of the tibioperoneal trunk extends
into both the peroneal and posterior tibial
arteries. (D)A wire is placed in each tibial artery.
(E)Kissing balloons placed and inflated simul-
taneously in the posterior tibial and peroneal
arteries.
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What about spasm? 211
not necessarily a bad sign when it occurs. In this
arterial segment, where there are fewer options for
bailout with stents and where prolonged balloon
angioplasty is usually the best treatment, it is usu-
ally best to keep the balloon inated and simulta-
neously treat the patient’s pain.
WHAT ABOUT SPASM?
Spasm is not a frequent clinical problem. However,
a small minority of patients seem to be prone to
spasm. Arteries with severe atherosclerosis and
diuse plaque formation are less likely to develop
spasm since arterial wall thickening and plaque
formation tend to prevent this happening. e
runo arteries, however, may be less diseased
and more likely to spasm. Younger patients with
nonatherosclerotic conditions are more likely to
develop spasm. When one considers how oen and
aggressively endoluminal arterial manipulation is
performed, it is amazing that spasm does not occur
more oen.
Spasm is not much of a clinical issue at the bal-
loon angioplasty site. More commonly, it may be
considered as a possibility in the outow bed for
an angioplasty site or in a neighboring segment of
the artery being treated. If the operator is unable to
visualize the end artery or outow vessels, it may be
due to poor technique, low ow, thrombosis, embo-
lization, dissection, or spasm. Spasm should only
be accepted as a diagnosis if the other possibilities
have been ruled out. Be sure that an adequate bolus
of contrast was delivered and that the concentra-
tion was appropriate. Check to see if there are rea-
sons for a low-ow state. e usual setting where
this comes up is in the course of an endovascular
intervention when an area of the outow can no
longer be visualized or appears substantially dier-
ent from the preintervention arteriogram.
When this occurs immediately aer balloon
angioplasty and involves the angioplasty site, it is
probably dissection. Usually there is some evidence
of trapped contrast in the few centimeters distal to
the angioplasty site. If t his occurs immed iately aer
balloon angioplasty and involves a distant outow
bed, it is probably embolization and/or thrombus,
especially if the angioplasty site looks technically
well treated but ow remains slow. Spasm may be
initiated by endovascular manipulation, even by
just a guidewire, ischemia, or contrast administra-
tion. e arteries most prone to spasm include the
distal internal carotid, axillary, brachial, renal, and
tibial arteries. Balloon angioplasty in these vascu-
lar beds oen includes administration of a vasodi-
lator, such as nitroglycerine. If spasm occurs, leave
a guidewire across, but withdraw everything else
you can, such as sheaths and catheters. Administer
additional heparin intravenously if there is a pos-
sibility that there is thrombus or embolus present
and nitroglycerine into the treated artery.
Strategy: Options for treating residual
stenosis after balloon angioplasty
Some residual stenoses do not require treat-
ment. e degree of residual stenosis that may
be acceptable is dictated by the clinical situation
(Figure 18.5). For example, a mild-to-moderate
residual iliac artery stenosis may be acceptable
aer angioplasty of a critical lesion in a patient
with rest pain and high surgical risk, but not in a
patient who also needs a femoral–tibial bypass for
extensive pedal gangrene.
1. During initial evaluation of the lesion, if it
is extremely heavily calcied and eccentric,
consider debulking with atherectomy instead
of treating with angioplasty.
2. If the signicance of a mild-to-moderate
residual stenosis aer a standard angioplasty
is not clear, measure pressure across the lesion.
Proceed with other steps listed in Table 17.5 in
Chapter 17 on assessing the results of balloon
angioplasty.
3. If the atherosclerotic waist fails to resolve,
repeat dilation (up to several times) with the
same diameter balloon but to a higher pressure
and with a longer expansion time. Dilation of a
residual lesion with the shoulder of the balloon
is sometimes eective when the middle of the
balloon may not have been.
4. If the initial balloon choice is unable to with-
stand higher pressures and ruptures, use a
high-pressure polymer balloon.
5. If it is an artery in which a stent is not desir-
able, consider a modied balloon such as a
scoring or cutting balloon.
6. Place a stent and perform poststent placement
balloon angioplasty, especially if the residual
stenosis exceeds 30%. Stent placement is now
fast, reliable, and durable and it may be more
ecacious to proceed to stent placement early,
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212 More about balloon angioplasty: Keeping out of trouble
rather than struggle with a dicult residual
stenosis and risk arterial rupture from overdi-
lation (see Chapter 19). Stent placement is indi-
cated in most vascular beds when the results of
angioplasty are not adequate.
PREVENTING PUNCTURE SITE
THROMBOSIS
rombosis at the access site is rare aer arteriog-
raphy since catheters are small in caliber and the
indwelling times are short. is problem is more
common aer endovascular therapy than aer
arteriography. When endovascular manipulation
proceeds from strategic to therapeutic, the devices
become larger, the length of time they are in the
artery is longer, blood ow through the artery at
the puncture site area may be altered by upstream
endovascular intervention, and postprocedure
hemostasis is more dicult aer use of larger cali-
ber sheaths. Avoiding puncture site thrombosis of
the access artery during the angioplasty procedure
relies on the skills learned in planning arterial
access and in the strategy for performing interven-
tions (Table 18.1). Keep in mind how the sheath itself
may alter ow. For example, if the puncture site is
near a lesion, the presence of the sheath within a
moderate lesion may cause a signicant alteration
in ow. If outow is poor and inow is improved
and the puncture site is in between the two, hemo-
stasis will be more challenging. If a long sheath is
used to extend into an artery that is only slightly
larger than the sheath, the ow may be impeded.
Prior to the procedure, feel the artery. If it feels
calcied or aneurysmal, perform a duplex evalua-
tion. Access through a heavily calcied or critically
stenotic common femoral artery is not advised. Do
not puncture an aneurysm. Careful attention to
anatomy and landmarks will assist the operator in
avoiding a low puncture at the femoral bifurcation.
When initiating the procedure, use ultrasound
guidance. is is the best way to improve the like-
lihood of a safe access.
Access that is adequate for arteriography may
not be satisfactory for endovascular therapy and
the larger sheath that is required. If arteriography
shows a critical lesion just distal to the location
of the access site, do not enlarge the arteriotomy
with a sheath. Obtaining hemostasis later will
be dicult without stopping ow altogether and
A
B C D
Fig. 18.5 Management
of residual stenosis after
angioplasty. (A)Aresidual
common iliac artery ste-
nosis remains after bal-
loon angioplasty. (B) If the
significance of the lesion is
not clear, arterial pressure
can be measured proxi-
mally and distally to the
lesion to assess whether
there is a pressure gradi-
ent. The distal pressure is
measured either through
a straight catheter pulled
down through the lesion
or through the side arm
of the hemostatic sheath.
(C)Repeat dilation is per-
formed to a higher pressure
using longer expansion
times. (D)Astent is placed
at the site to treat the
residual lesion. Poststent
placement balloon angio-
plasty is often required.
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Balloon angioplasty troubleshooting 213
risking thrombosis. Consider performing inter-
vention through an alternative access site.
Aer obtaining access, use the smallest caliber
catheters and sheaths that are adequate for the job.
Arteriography can oen be accomplished with 4-Fr
catheters. Balloon angioplasty may be performed
up to a diameter of 8 mm with a sheath of 6-Fr or
smaller. Upsizing of sheaths is done aer consid-
eration, since it also increases the risk of puncture
site problems. If the puncture is close to a lesion
that may cause a problem, do not upsize the sheath.
Aer sheath removal, when manual pressure is
held to achieve hemostasis, ow through the access
artery should be allowed to continue so that plate-
lets deposit at the puncture site to initiate platelet
plug formation. If pressure is held too aggressively
and ow is stopped, brin-rich thrombus begins to
form and a puncture site thrombosis is more likely
to occur. When closure devices are used, obtain a
femoral arteriogram rst and follow the instruc-
tions for use for each specic device, since they all
have limitations.
BALLOON ANGIOPLASTY
TROUBLESHOOTING
Assessment of working room or distance between
the arterial access site and the balloon angioplasty
site is performed on every case. Long distances
require that appropriate length guidewires and
catheters are available (see Chapter 4, Tables 4.2
and 4.3). is is discussed in greater detail in
later chapters describing angioplasty in specic
arterialbeds. Occasionally, working room is inad-
equate. Adequate working room requires that a
standard 12-cm access sheath is able to t between
the puncture site and the lesion. If the tip of the
sheath extends to the lesion, the working room
will not be sucient to pass catheters and perform
interventions. Options include a percutaneous
approach at an alternative location, an arterial cut-
down at another location if percutaneous access is
not possible, or proceeding with the same access
site with the sheath partially withdrawn and well
secured (Figure 18.6). When working room is
tight, use a short bright tip sheath and support it
manually as needed.
Balloon rupture within the specied ina-
tion pressure is possible when an attempt is
made to dilate a sharp or heavily calcied lesion
(Figure 18.7). Occasionally, even aer balloon
rupture, a partial or complete dilation of the
lesioncan be accomplished by exerting high pres-
sure on the balloon. is allows the balloon to ll
to the maximum extent possible by overwhelming
the leak. Usually, however, it is necessary to switch
to a thicker and more puncture-resistant polymer
balloon. e shoulder portion of the balloon oen
successfully dilates this type of lesion without rup-
ture. e balloon is advanced in small increments
and several inations are required to dilate the
entire lesion with the shoulder of the balloon. If the
balloon ruptures again, placing a stent and dilating
the lesion through the stent should be considered.
Occasionally, the nearly fully expanded bal-
loon herniates past the resistant lesion, either
Table 18.1 Preventing puncture site thrombosis after endovascular intervention
• Palpate anatomy prior to puncture; assess quality of pulse and whether the artery is hard.
• Use ultrasound-guided puncture to avoid accessing near a lesion.
• Do not puncture an aneurysm.
• Do not puncture a heavily calcified or critically stenotic artery.
• Do not puncture the femoral bifurcation.
• Use small caliber catheters and sheaths whenever possible.
• Do not upsize the sheath if there is a critical lesion very near the puncture or the artery was more
hostile than anticipated. Consider approaching the lesion from another access site.
• Hold pressure carefully between all catheter or sheath exchanges to prevent the accumulation of
blood under the skin around the artery puncture site.
• Treat the arterial access site gently; use dilators to make a smooth track.
• If hemostasis is achieved by manual compression, when pressure is held, do not stop flow through
the artery.
• Consider using a closure device and plan the access site with that in mind.
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