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194 Balloon angioplasty: Minimally invasive autologous revascularization
is low. If it is a semicompliant balloon with a
range of diameters that can be reached with
increased pressure, the operator can adjust the
dilation during the procedure. Another method
of doing this is to perform a road map of the
artery, inate the balloon superimposed on the
road map, and look for the appropriateness of
the size match. e operator will have a sense
for whether the balloon appears appropriate for
that artery. If it appears that the balloon is too
small, it may be exchanged for a larger one. If
it appears to be appropriate in size, the opera-
tor proceeds to evaluate the treated artery for
evidence of residual stenosis. Steps for assessing
the adequacy of angioplasty are described later
in this chapter.
2. Digital measurement. Another option is to
perform arteriography with a catheter that
has graduated radiopaque centimeter mark-
ers and to use this known length to calculate
vessel diameter. is method is not without the
potential for error. If the catheter is traveling in
the anteroposterior plane, the marked centimeter
may appear shorter than it really is and cause an
overestimation of vessel size. Avariation of this
method is available in some angio suite cockpits
that have the soware to estimate vessel diam-
eter using a known standard for comparison,
such as a 5-Fr catheter. is takes a moment, so it
does tend to interrupt the ow of the procedure.
ere are also potential sources of error based on
where the cursor is placed. What many opera-
tors nd is that the visual assessment is fast and
workable and rarely leads to trouble. Given that
digital measurement also has the potential for
small errors of diameter assessment, it is really
up to the operator which method to use to assess
the diameter of the artery. Dissection or rupture
can result if the balloon is too large, therefore
when in doubt, start small.
e balloon should be long enough to dilate the
lesion in a single ination, if possible, and allow a
short overhang on either end. Balloon length choices
have increased signicantly over the past few years.
If a balloon is available that can be used to dilate the
entire lesion in one single ination, it is faster and
probably a little less likely to cause as much dissec-
tion as when multiple overlapping inations with a
short balloon are performed. If the balloon used is
too short to cover the whole diseased segment, addi-
tional inations are required. Longer balloons have
been developed, especially for lesions of the super-
cial femoral, popliteal, and tibial arteries.
e prole of the unexpanded balloon is impor-
tant to ease passage through the sheath and across
the lesion and should be minimized as much
as possible. Other balloon types may be chosen
for certain lesions. Reinforced polymer (high-
pressure) balloons are used for recalcitrant lesions.
Puncture-resistant balloons are used for placement
of balloon-expandable stents. e sha length
must be adequate to reach the lesion from the
entry site. Sha size should be as small as possible.
Most angioplasty is performed with either 3-Fr or
5-Fr balloon catheters, for low-prole (0.014-inch)
and standard (0.035-inch) systems, respectively.
e hemostatic access sheath should be selected in
anticipation of the balloon to be used. If a stent is
likely to be required to treat the lesion, the opera-
tor will choose the sheath size in anticipation of
the balloon–stent combination. More information
about sheaths can be found in Chapter 14.
e length of the balloon catheter itself must
also be considered. More information about this
can be found in the individual chapters about
intervention in specic vascular beds. Table 17.2
provides some guidelines. Balloon catheter lengths
vary from 40 to 150 cm. A full complement of
balloon catheter lengths should be maintained
in an active inventory. Longer catheters, ranging
Table 17.1 Balloon sizing for angioplasty
a
Angioplasty site Balloon diameter (mm)
Abdominal aorta 8–18
Aortic bifurcation
b
6–10
Common iliac artery 6–10
External iliac artery 6–8
Superficial femoral artery 4–7
Popliteal artery 3–6
Tibial artery 1.5–4
Renal artery 4–7
Subclavian artery 5–8
Dialysis graft 4–6
Infrainguinal graft 4–6
a
Each arterial segment has a general range of appro-
priate balloon sizes from which to choose.
b
When kissing balloons are used at the aortic bifurca-
tion, the diameters of the 2 balloons are additive.
Kissing 10-mm balloons should be used only if the
distal aorta can tolerate dilation to 20 mm.
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Supplies for percutaneous balloon angioplasty 195
from 90 to 120 cm, are also useful for angioplasty
using remote access. e length of the angioplasty
catheter sha can usually be estimated using the
catheter length required to perform selective angi-
ography of the lesion.
Strategy: How to choose the right
balloon for the job
1. Balloon diameter. Start small if there is any
doubt. Use guidelines based on which artery is
being dilated (Table 17.1).
2. Balloon length. Aim to cover the lesion and a
little beyond.
3. Balloon type. Choose material based on the
type of lesion.
4. Sha length. Must reach the lesion from the
entry site (range from 75 to 150 cm). Table 17.2
provides guidelines for choosing balloon cathe-
ter lengths. Additional information is available
in the sections on angioplasty at specic sites.
5. Sha size. Use as small a sha size as possible
(usually 3-Fr or 5-Fr).
6. Shoulder length. e length of the shoulder
is important if the lesion is near an area that
should not be dilated. e shoulder of the bal-
loon is the end that extends beyond the radi-
opaque marker. If the shoulder extends into an
adjacent branch vessel that is not intended for
treatment, overdilation may result.
7. Balloon prole. A lower prole is better but the
prole varies with balloon type and to some
extent from one manufacturer to another.
WHEN TO USE A MONORAIL
SYSTEM
Larger platform devices (0.035-inch and 0.038-
inch compatible) are designed for use in coaxial
systems. Smaller platform systems (those designed
for use with 0.014-inch guidewires) may be either
coaxial or monorail systems. Some procedures
are substantially facilitated by low-prole mono-
rail systems. ese include carotid stenting,
some tibial interventions, and other small artery
procedures. e residual lumen of a critical or even
preocclusive stenosis much more readily accepts
a lower-prole guidewire. ere are several situa-
tions where either a monorail or a coaxial system
is satisfactory. ese include supercial femoral
arter y (SFA) interventions and renal a nd subclavian
stenting. Many operators are using the monorail
system with increasing frequency in these vascular
beds, especially since a stent can oen be placed
through the lesion without predilation when using
the smaller platform systems. ere are also some
situations where the overall strength and prole of
the 014 system are not adequate for the procedure,
including most aortic and iliac cases.
SUPPLIES FOR PERCUTANEOUS
BALLOON ANGIOPLASTY
Table 17.3 is list of items that should be available
to initiate a balloon angioplasty procedure. (See
Chapter 10, Table 10.1 for an “arteriography pack”
of basic supplies.) An inventory of disposable
Table 17.2 Angioplasty balloon catheter length
Location of
balloon
angioplasty Entry site
Length
(cm)
Carotid Femoral 110–130
Subclavian Femoral 110–120
Brachial 75
Visceral Femoral 60–75
Renal Femoral 60–75
Brachial 90–110
Aorta Femoral 65–75
Iliac Ipsilateral femoral 40–75
Contralateral femoral 75
Femoropopliteal Ipsilateral femoral 75
Contralateral femoral 75–110
Infrapopliteal Ipsilateral femoral 75–90
Contralateral femoral 90–150
Table 17.3 Supplies for balloon angioplasty
Starting guidewire Balloon angioplasty catheter
Selective guidewire Inflation device
Exchange guidewire Balloon-expandable stent
Dilator Self-expanding stent
Flush catheter Arteriography pack
Selective catheter Heparinized saline
Exchange catheter Contrast
Access sheath
Guide sheath
Protective gear
(e.g.,leaded apron)
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196 Balloon angioplasty: Minimally invasive autologous revascularization
endovascular supplies, such as guidewires, cath-
eters, sheaths, angioplasty balloons, and stents,
must be maintained and continuously updated.
More specic information about which supplies
should be available for balloon angioplasty can be
found in the chapters that cover intervention in the
dierent vascular beds.
SHEATH SELECTION AND
PLACEMENT
Sheaths have been introduced and discussed in
Chapter 14. Sheath access to the arterial system is
part of the standard approach to percutaneous bal-
loon angioplasty.
e access sheath maintains control of the
access site, provides hemostasis, and functions
asa conduit for simple placement of balloon cath-
eters and angiographic catheters. In general, the
sheath is selected on the basis of the French sizing
of itscaliber and its length. General access sheaths
are straight and are available with radiopaque tips
if desired. Special sheath congurations may be
required for some types of angioplasty where a
high degree of selectivity is required. ese guid-
ing sheaths are discussed in Chapter 14.
e size of the sheath is selected to t the endo-
vascular device. In the case of balloon angioplasty,
the sheath must accommodate the balloon aer
it has been inated and aspirated and it is time to
withdraw it from the patient. (See Chapter 14, sec-
tion ‘What Fits Into What?’ [Table 14.3].) As a gen-
eral rule, a 5-Fr sheath will accommodate balloons
up to 6 mm. A 6-Fr sheath will permit balloons up
to 8 mm to pass. A 7-Fr sheath will accommodate
a balloon up to 10 mm, as long as it is mounted
on a 5-Fr sha. Larger balloons may come on 5-Fr
shas or larger and generally require 8-Fr to 10-Fr
sheaths.
If stent placement is anticipated, the sheath size
must be increased accordingly. Most peripheral
indications that require either balloon- expandable
or self-expanding stents up to 10 mm can be man-
aged with 6-Fr or 7-Fr sheaths. Balloon-expandable,
premounted stents may also be obtained on 0.018-
inch compatible systems, which permits placement
of an 8 mm stent through a 6-Fr sheath. Self-
expanding nitinol and other metal stents require
a 6-Fr to 9-Fr sheath, depending on the diameter
of the stent. Vessel diameters up to 12 mm can
be treated with self-expanding stents using 6-Fr
sheaths. More information about sheath sizing
requirements for stent placement can be found in
Chapter 19. Self-expanding stents with larger diam-
eters of 12 mm or more have a variety of indica-
tions. In the venous system, stents up to 24 mm in
diameter may be indicated and a sheath up to 12-Fr
required to place it. However, sheath sizes on the
lower pressure venous system are less crucial than
when large bore access is required for arterial revas-
cularization. In addition, a variety of covered stents
are available, with their own sheath size require-
ments, and this is discussed in Chapter 18. e
important issue is that the operator must take into
account the entire procedure before initiating treat-
ment with balloon angioplasty.
Sheath type, size, and length should be selected
based on the individual case. How to do this
is described in Chapter 14. Later in the book,
when therapy is described for specic vascular
beds, this issue is considered in more detail. e
sheath is placed over the guidewire, to the desired
location. e usual scenario is that aer arteriog-
raphy, the catheter (either a ush or selective cath-
eter) through which it was performed is already
in place. An exchange guidewire is then placed
through the catheter and the catheter removed.
e sheath that has been selected to use as a plat-
form for treatment is placed over the exchange
guidewire. Pressure is held at the arterial punc-
ture site as the angiographic catheter and/or ini-
tial access sheath are removed and the treatment
sheath is placed. Preparation and management of
the sheath are detailed in Chapter 14. e sheath is
advanced into the desired position and the dilator
removed. Turn the sheath appropriately so that the
side arm is oriented toward the operator for ease
of use. e sheath may be rocked back and forth
slightly during advancement to help make this
easier. As the tip of the sheath enters the skin entry
site, the sheath is gripped by the operator along its
sha, close to its leading edge. Watch the sheath
to ensure that the dilator does not pop backward.
Most sheaths have a mechanism to lock the dilator
in place. If the lesion is in proximity to the arterial
entry site, care should be taken to avoid advanc-
ing the sheath, or the dilator tip, across the lesion
and unintentionally dottering the planned balloon
angioplasty site. e sheath is generally advanced
to its hub, unless it is too close to the lesion. Aer
the dilator is removed, the sheath is ushed with
heparinized saline. Arteriograms are obtained
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Heparin administration during intervention 197
prior to endovascular treatment. Placement of an
external marker, such as radiopaque marking tape,
is performed at this point if desired and a contrast
run is performed with the marker in place. is
run with the marker helps select the length of the
balloon.
BALLOON PREPARATION AND
PLACEMENT
e balloon catheter is taken from its sterile
package. e protective plastic cover that is placed
over the balloon for shipping is removed. is is
saved on the sterile eld so that it can be used to
help refold the balloon wings later if the catheter is
going to be used again during the same procedure.
Balloons of widely varying diameters appear simi-
lar in the nondilated state, tightly folded around the
sha. Prior to insertion, the operator must ensure
that the correct size of balloon is being placed by
checking the size inscribed on the balloon cath-
eter head. Inadvertent ination of a balloon that is
too large must be avoided. e catheter and bal-
loon are wiped with a heparin–saline soaked gauze
sponge. e guidewire (distal) port is irrigated
with heparin–saline. e balloon should not be
preinated; this raises the prole of the balloon.
e manufacturing companies are responsible for
quality control and do a remarkable job, in general.
e balloon catheter is placed on the guidewire and
advanced toward the entry site until wire is avail-
able to be grasped on the other end of the catheter.
Do not insert the balloon catheter unless manual
guidewire control has been achieved.
Monorail balloons are prepped by wiping the
catheter. ere is usually a throwaway metal wire
or trocar in the short guidewire port to keep the
treatment end of the balloon catheter straight and
protected. is is removed. e balloon catheter
usually comes with a small gauge needle that is
used with a 3-mL syringe to ush air out of the
guidewire port. is guidewire port ush is very
important in the carotid circulation, where every
eort must be taken to remove air from the sys-
tem prior to initiating treatment. Do not kink
the sha of the catheter, otherwise it will be dif-
cult to pass the guidewire through it. e balloon
port is aspirated with a syringe containing dilute
contrast. As suction is applied, air bubbles egress
and are replaced as far as possible with the dilute
contrast. is maneuver is called “priming” the
balloon catheter. In general, low-prole (0.014-
inch or 0.018-inch) balloons are small enough that
even a small amount of air in the balloon during
ination makes the visibility poor. In addition,
if the balloon pops during usage in the carotid
system and air bubbles are released, this could lead
to a neurologic event. e small caliber balloons
are “primed” or prepared using a small syringe of
dilute contrast, usually a 50/50 mixture. e bal-
loon catheter is gently aspirated, air bubbles come
out, and these are replaced passively with a few
drops of contrast. is is done several times until
no additional bubbles can be removed. e balloon
is not inated; this is done by gentle aspiration and
then passive release of the syringe to replace air in
the dead spaces with uid.
HEPARIN ADMINISTRATION
DURING INTERVENTION
ere are no clear scientic data on how much
anticoagulation is required for safe conduct of
interventions. Heparin is most widely used, but
other agents are available and are described in
Chapter 13. A wide variety of heparin protocols
are available and these may vary tremendously
from one practice to the next. Previously, one of
the main considerations was that if the patient
was fully anticoagulated, the ability to remove
the sheath and achieve adequate hemostasis with
manual compression would be compromised for
a couple of hours. e addition of closure devices
has generally alleviated this concern and in each
case the patient can be anticoagulated based on the
needs of the procedure, rather than the logistics
of what happens aer the procedure. One way of
proceeding with periprocedural anticoagulation is
described here.
Heparin is administered as indicated by the
type of procedure being performed (Table 17.4).
Usually, administration of 100 units/kg body
weight will achieve an activated clotting time
(ACT) of >250 seconds. is is the ACT level
generally used for percutaneous coronary inter-
ventions. Some patients are heparin resistant
and, occasionally, a patient will require two or
three times this amount of heparin. Although
heparin resistance is rare, it is important to
check the ACT to ascertain if this is so, and this
is highly individualized from operator to opera-
tor. In general, the smaller the artery, and slower
https://t.me/med1917
198 Balloon angioplasty: Minimally invasive autologous revascularization
the ow, the more anticoagulation is required.
More thorough anticoagulation is desirable in
procedures that involve carotid and tibial or
pedal vessels. Renal and visceral cases require
more anticoagulation than routine iliac or SFA
cases. During drug-coated balloon angioplasty
of the lower extremity, even for a routine lesion,
if balloon ination is planned for 3 minutes, the
ACT should be more than 180 seconds to avoid
thrombus formation. ere may be other situa-
tions where more anticoagulation is desired. If
ow will be stopped for more than a few minutes
(e.g., large sheath passing through small artery or
through a moderate stenosis that compromises
ow), the patient should be fully anticoagulated.
If there is a potential that the primary lesion
intended for treatment has caused embolization,
more anticoagulation is indicated.
When heparin administration is required, this
should occur at least 3 minutes prior to balloon
ination. As with open vascular surgery, there
is a high degree of variability between dierent
vascular specialists as to appropriate heparin indi-
cations and dosages. Table 17.4 lists one operator’s
method and is intended for use as a general guide-
line. Before placing the balloon catheter, conrm
the appropriate heparin administration and pre-
pare the ination device so that angioplasty is
ready to proceed as soon as the balloon is in place.
e balloon catheter is advanced through the
sheath (Fi gure 17.3). e location of the lesion is
marked aer arteriography using bony landmarks,
an external radiopaque marker, or road mapping.
e catheter is advanced using uoroscopic guid-
ance, and the radiopaque markers on the balloon
are placed across the location of the lesion. e
shoulder of the balloon must not extend into an
area where angioplasty is not desired. e balloon
is centered in the lesion so that the most stenotic
segment is dilated by the central portion of the
balloon.
Technique: Tips for optimal
angioplasty
1. Use correct balloon diameter and length, as
described in the preceding sections.
2. Use a single balloon to treat entire lesion if pos-
sible, with a slight amount of balloon overhang
beyond the end of the lesion.
3. Slow ination. Inate balloon 1–2 atm at a time
until a waist forms. Leave the balloon static
for 20 seconds and see if the waist opens on its
own.
4. Slowly inate the balloon until the waist is
resolved.
5. Ideal balloon ination time is 2–3 minutes.
6. Bring the balloon ination to nominal pressure
as indicated by the desired vessel diameter.
7. Release the balloon by dialing down the pres-
sure on the ination device.
BALLOON INFLATION
Balloons can be inated with 2–12 mL of contrast
and saline solution, depending on the diameter and
length of the balloon. e ination devices usually
hold 10–15 mL. A 30% to 50% contrast solution
allows the outline of the balloon to be visualized u-
oroscopically. Full-st rength contrast is more viscous
and therefore prolongs ination and deation and
is not used for this purpose. Air should be removed
from the ination device. Sizable air bubbles inside
the balloon may make it dicult to tell whether or
Table 17.4 Heparin administration during percutaneous balloon angioplasty
Procedure Systemic heparin administration (units/kg) Other considerations
Brachiocephalic 100 Dual antiplatelet therapy
Renal 75–100 Nitroglycerine for spasm
Aortoiliac
Simple 50–75
Complex 75
Femoropopliteal
Simple 75
Complex 75–100
Tibial or pedal 100 Nitroglycerine for spasm
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Balloon inflation 199
not the balloon is fully expanded. If the balloon
breaks, the patient will receive an intra-arterial
bolus of air. When using small caliber balloons, air
in the balloon may make it impossible to visualize
the inated balloon. Balloon ination is usually, but
not always, performed with an ination device. e
plunger on the ination device is compressed until
a few atmospheres register on the pressure gauge.
e plunger is locked in compression mode. At this
point, the outline of the partially inated balloon is
visible on the uoroscopic monitor. Ination of the
balloon is completed by turning the screw handle of
the ination device to gradually increase pressure
in the balloon while the uoroscopic image is mon-
itored for complete balloon dilation. An ination
device permits pressure within the balloon to be
measured during ination to avoid exceeding the
balloon’s bursting pressure. Observation of balloon
expansion can be compared with the pressure data
to gain a better understanding of the lesion. Higher
pressures required to dilate recalcitrant lesions
can be sustained and monitored with an ination
device. When kissing balloons are required, as with
aortic bifurcation lesions, pressure in the two bal-
loons can be equalized by simultaneous use of ina-
tion devices.
e balloon may also be inated by hand. A
10-mL syringe is lled to the 8-mL level and used
to expand the balloon directly by hand-generated
pressure. is is eective but may generate high
A B C D
Fig. 17.3 Balloon angioplasty. (A) The guidewire is placed across an external iliac artery stenosis.
Thediameter of the balloon is selected based on the diameter of the uninvolved, juxtaposed iliac
artery as measured on an arteriogram. (B) The balloon catheter is passed over the guidewire, through
the hemostatic sheath, and into position across the stenosis. (C) The balloon is inflated using an infla-
tion device. Pressure within the angioplasty balloon can be monitored as the waist of atherosclerotic
material resolves. (D) The lesion is fully dilated and the cylindrical shape of the balloon is confirmed
using fluoroscopy.
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200 Balloon angioplasty: Minimally invasive autologous revascularization
pressures, which are not desirable. Use a Luer Lock
syringe when dilating by hand. In practice, this
is simple, fast, and inexpensive, but probably not
designed for optimal results of angioplasty.
Angioplasty is performed without delay aer
the balloon is placed, since the presence of the
catheter alone in the remaining patent lumen can
decrease ow and enhance thrombus formation.
With drug-coated balloon angioplasty, there is
also the potential that medication will be released
from the balloon while it sits uninated in the ow
stream. Angioplasty is performed using intermit-
tent uoroscopic guidance. Atherosclerotic nar-
rowing makes itself apparent on the outline of the
balloon as it is being inated under uoroscopy
(i.e., by the atherosclerotic waist). e atheroscle-
rotic waist, which is present at the most stenotic
part of the lesion, usually resolves when adequate
pressure is applied by the balloon (Fig u re 17.4).
Usually, as the waist of atherosclerosis gives way,
there is a perceptible decrease in pressure in the
balloon. For example, the ination device may
read 6 atm and suddenly decrease to 4 atm. e
accompanying uoroscopic image usually dem-
onstrates the balloon coming into prole as that
occurs.
ere are many recommendations to guide
ination parameters but almost no data to support
them: the amount of pressure to apply, the length
of time balloon ination is maintained, the num-
ber of times the balloon is expanded at the same
location, and the length of time between ina-
tions. Acommon approach is to dilate a lesion to a
slightly higher pressure than that required for full
balloon expansion as observed under uoroscopy.
A slow ination is thought to decrease the rate
of severe dissection. Ination is maintained for
a minimum of 60 seconds. Additional inations
2
0
4
6
8
10
ATM
12
14
16
18
20
2
0
4
6
8
10
ATM
12
14
16
18
20
2
0
4
6
8
10
ATM
12
14
16
18
20
2
0
4
6
8
10
ATM
12
14
16
18
20
2
0
4
6
8
10
ATM
12
14
16
18
20
A B C
D E
Fig. 17.4 Dilating the atherosclerotic waist. This is an example, but the principle generally holds true
that with steadily increasing balloon pressure, most lesions will give way to dilation. (A) The balloon
catheter is placed within the lesion. The radiopaque markers straddle the stenosis. (B) The balloon
begins to take shape at low pressure. (C) At 2 atm of pressure, the waist begins to become evident.
A waist of atherosclerotic material represents the area of heaviest plaque formation and is usually the
last area to be fully dilated. (D) At 4 atm of pressure exerted by the balloon, a substantial residual,
unresolved stenosis is apparent. (E) When the pressure is doubled to 8 atm, the waist of atherosclero-
sis has been completely dilated. As the plaque shifts, it is common to notice a small but spontaneous
decrease in pressure reading.
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Balloon removal and completion arteriography 201
to higher pressure are recommended if a waist is
still present at the lesion. In practice, however, it is
usually acceptable to dilate the lesion with a single
balloon ination until the waist expands. Longer
ination times at higher pressures are required
for intimal hyperplasia, recurrent lesions, residual
lesions, and occasionally heavily calcied lesions.
Most lesions are fully dilated with less than 8 atm
of pressure. Intimal hyperplasia is a notable excep-
tion and may require 20 or 30 atm. Resolution of
the waist is an important factor in assessing the
adequacy of dilation. If the balloon will not main-
tain pressure, this may be due to rupture of the
balloon. Sometimes, contrast can be seen leak-
ing from the balloon on the uoroscopic image.
Aspiration of the balloon may reveal blood in the
ination mixture. Usually, the balloon must be
exchanged in this case. Deate the balloon as well
as possible. Remove the balloon under uoroscopic
guidance to be certain that theirregular, torn bal-
loon wings are not caught onthe lesion.
e likely shape of the balloon aer ination
is anticipated by the operator in deciding where
to place it. Already mentioned is the concept that
the shoulder of the balloon should not protrude
into an adjoining segment that the operator is not
intending to dilate. In addition, if there is an area
of tortuosity or the balloon is placed around a cor-
ner, the balloon will straighten out when inated.
e balloon is a longitudinal structure. When it
is fully inated it will completely straighten out
and will not angulate around a corner or a bend.
is is usually not a signicant issue but the opera-
tor has to be able to anticipate what the shape of
the inated balloon will look like. When dilating
a branch vessel from the aorta, the longitudinal
nature of the balloon ination has to protrude
somewhere, and this is usually into the aorta.
e small caliber, lower-prole, monorail sys-
tem balloons are oen semicompliant in order
to adjust to small changes in the sizes of smaller
arteries. In this case, the higher the adminis-
tered pressure, the larger the resulting balloon
diameter. Each semicompliant balloon comes with
a specication sheet that correlates the number of
atmospheres of pressure with the diameter of the
balloon when inated.
A common nding in the awake patient is a
complaint of pain at the angioplast y site during ba l-
loon ination. is generally is a sign that balloon
pressure has reached its reasonable maximum.
e pain should resolve when the balloon is
deated. Continued pain may be a sign of dis-
section or rupture and should be evaluated with
immediate repeat angiography. In the sedated
patient, even if there is not a specic complaint,
there is frequently a more subtle response such as
some movement or a change in breathing pattern.
is kind of information helps the operator under-
stand the patient’s tolerance and also know that the
balloon size is in the right range. When a patient
feels the ination of the balloon, the upper range
of acceptable balloon size is close.
When residual stenosis is present, usually the
balloon is inated at the same location to a higher
pressure. e physics of expansion of the shoulder
of the balloon is a little dierent to expansion of
the middle portion of the balloon, and this seems
to be able to generate more expansion force. If
reinating the balloon does not work, sometimes
reinating it with the shoulder located at the recal-
citrant segment is helpful.
Aer angioplasty, the balloon is completely
deated. e balloon port is aspirated vigorously,
usually by reversing the plunger on the ination
device to apply suction or negative pressure to
the balloon. If this method is not adequate or is
too slow, the operator can use an empty 20-mL or
30-mL syringe. e balloon is not moved until it is
visualized, using uoroscopy, to ensure complete
deation.
BALLOON REMOVAL AND
COMPLETION ARTERIOGRAPHY
e balloon should be withdrawn but the guide-
wire kept in place. Occasionally, the balloon mate-
rial catches on some irregular or sharp part of the
dilated lesion, usually when there is signicant
calcication. If the balloon is caught, deate it
again with constant negative pressure. Rotate the
balloon on the guidewire. Advance the catheter
a centimeter and then withdraw it. Remember to
hold the sheath so that it does not pull out when
the balloon catheter is removed. When the balloon
wings reach the tip of the sheath, there is increased
resistance as the redundant material is forced into
the sheath.
ere are several methods of assessing the results
of balloon angioplasty (Table 17.5). Acombination
of these methods is usually performed. Completion
arteriography is the most widely applicable method.
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202 Balloon angioplasty: Minimally invasive autologous revascularization
e quality of completion arteriography may be
improved by magnied views of the angioplasty
site, oblique views, and a qualitative assessment of
contrast ow through the angioplasty site during
digital subtraction arteriography. In general, a
residual stenosis of less than 30% is acceptable, even
if the angioplasty site has a somewhat irregular
surface. Although completion arteriography is the
most widely used and readily accessible method of
assessing the results of balloon angioplasty, aer
the dissection planes are raised by angioplasty the
degree of stenosis may be very dicult to assess.
Pressure may be measured proximally and dis-
tally tothe lesion. is is relatively simple to do by
measuring the pressure through an angiographic
catheter placed over the guidewire that crosses
the angioplasty site, and measuring through the
side arm of the sheath that is on the other side of the
angioplasty site. A pressure wire may also be used to
make this assessment. Any pressure gradient follow-
ing angioplasty is probably signicant. Remember
that when outow occlusion is present, the pressure
will tend to equalize proximally and distally to the
lesion or the angioplasty site. IVUS may also be used
in this setting and is most accurate for assessing the
precise degree of stenosis aer angioplasty.
Fi gure 17.5 illustrates methods for performing
completion arteriography aer aortoiliac angio-
plasty. If the sheath tip is in proximity to the treat-
ment site, contrast can usually be administered
through the sheath and will illuminate the results
of balloon angioplasty. Completion arteriography
may also be performed using a catheter placed
through the sheath and over the access guidewire
aer the balloon catheter is removed. If a previous
contralateral puncture has been performed, a sepa-
rate catheter may be placed through this access site
to obtain a completion study. Sometimes, comple-
tion arteriography is performed simply by injecting
contrast through the side arm of the sheath with the
tip either proximal or slightly distal to the angio-
plasty site. High-pressure contrast injection should
not be performed directly into the fresh angioplasty
site because it may extend a local dissection plane
caused by the balloon injury. General options and
techniques for completion arteriography at various
sites are presented in Table 17.6. Further examples of
completion arteriography are provided in the chap-
ters on angioplasty in dierent vascular beds. In
general, if the angioplasty site is downstream from
the access site, contrast is administered through the
sheath to evaluate the results of treatment. A com-
mon example of this is in infrainguinal angioplasty,
in which the access sheath is always approaching
from the proximal portion of the artery.
e guidewire is maintained in its position
across the lesion until the completion arteriography
has been deemed satisfactory. If for some reason the
guidewire is no longer across the lesion and more
endovascular intervention is required, the lesion is
recrossed with a J-tip or atraumatic guidewire to
avoid entering a newly created dissection plane.
A balloon can be reused during the same
angioplasty procedure. e balloon arrives in the
package with a funnel-shaped plastic cover that
protects the balloon during shipping. With a rm
negative-pressure aspiration on the balloon port,
the balloon material can be folded and reshaped
by hand and advanced into the funnel to lower its
prole for repeat use.
Table 17.5 How to assess the results of a balloon angioplasty
a
Method Comment
Completion arteriogram Obtained in all cases
Magnified view Enhanced detail at angioplasty site
Oblique projection Assesses residual stenosis or dissection flap
Measure pressure Quantitative hemodynamic assessment
Intravascular ultrasound Useful for evaluating dissection or residual stenosis
Clinical evaluation Helpful in identifying complications
Hemodynamic stability
Pulse/color of extremity
Flank pain
a
Modified from Schneider PA. Balloon angioplasty catheters. In: Moore WS, Ahn SS, eds. Endovascular Surgery.
Philadelphia: WB Saunders, 2001:61.
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Balloon removal and completion arteriography 203
A
B
C
D
Table 17.6 Options for completion arteriography after endovascular intervention
General options
Technique
Proximal flush
catheter
Place flush catheter over guidewire used for balloon angioplasty. Place catheter
head proximal to balloon angioplasty site and administer contrast. Use flush
catheter to maintain control at intervention site. This technique is most common
in aortoiliac intervention
Access sheath Maintain guidewire control with original wire. Administer contrast through side
arm of access sheath. Tip of sheath must be proximal to lesion (e.g., in SFA
balloon angioplasty) or just distal to the lesion (e.g., retrograde femoral
approach to iliac lesion)
Straight catheter Place multiple side hole straight catheter through the lesion and remove the
guidewire. The straight catheter may extend slightly beyond the lesion and is used
to maintain control of the lesion. Contrast fills the angioplasty site by passing
through the side holes on the catheter. This technique is useful for side branch
balloon angioplasty, which is done without a guiding sheath (e.g., renal, subclavian)
Separate
catheter
Administer contrast through a separately placed catheter. When arteriography is
performed through one puncture site and intervention performed through an
alternative site, the original access site can be used for the completion
arteriography. An example of this is transfemoral arch aortography, followed by
transbrachial, retrograde subclavian intervention. The completion arteriography
is performed through a transfemoral catheter
Guiding sheath Long access sheaths with shaped tips are used for branch vessel balloon
angioplasty (e.g., carotid, renal). After angioplasty, contrast is administered
through the sheath and directly into the vessel origin
Fig. 17.5 Completion arteriography.
(A) After iliac angioplasty, the balloon
catheter is withdrawn from the angio-
plasty site. Completion arteriography
can be performed through a proximal
catheter placed in the aorta through
the contralateral femoral artery.
This is a reasonable approach if an
arteriographic catheter had been
originally placed to perform strategic
aortography prior to the angioplasty
procedure. (B) The balloon catheter is
removed and exchanged for an arte-
riographic catheter. The intraluminal
position across the angioplasty site is
maintained by the catheter itself and
the catheter tip is advanced proximal
to the lesion. (C) Another option is
to place the dilator into the sheath
and advance it through the lesion.
Contrast administration through the
side arm of the sheath permits com-
pletion arteriography. (D) Retrograde
arteriography can also be performed
through the sheath and this is usually
adequate.
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