PERIPHERAL VASCULAR DISEASE
32
Jeffrey A. Solomon, MD, MBA, and
Jeffrey I. Mondschein, MD
1. What is the appropriate landmark for a femoral artery puncture?
Some risks of arteriography can be minimized by properly selecting the puncture site. Above the inguinal canal, the
femoral artery (or, more correctly, the external iliac artery) dives posteriorly. Punctures above the inguinal canal may
be problematic for several reasons. Because the artery is so deep to the puncture site, manual compression may
be difficult, leading to a hematoma or pseudoaneurysm formation. In the event of an access site complication that
requires surgical intervention, the surgical approach for puncture above the inguinal ligament is more involved. A
puncture that is too low may result in an arteriovenous fistula. The inguinal crease is a landmark that is commonly
used for femoral artery puncture. This is a very inaccurate estimate for the location of the inguinal ligament,
especially in obese patients. The best landmark is the middle of the medial third of the femoral head identified
fluoroscopically (Fig. 32-1).
2. What is Cope s law of vascular access?
 You can t stick a vessel where it isn t. The puncture site should not be where
you think the artery might be, but instead where it actually is as determined with
palpation or ultrasound (US).
A
3. If the femoral artery cannot be accessed, what are other
options for obtaining access for an arteriogram?
Multiple options for access may exist in any given patient. The appropriate access B
site depends on the patient s symptoms, intended procedure, prior surgical history,
and clinical setting. A brachial approach may be used if a femoral approach is
C
impossible. Other access options include direct puncture of bypass grafts, direct
translumbar aortic puncture, and retrograde popliteal access.
4. If a brachial approach must be used, is the right or left arm
used?
D
A left brachial approach is preferred. A catheter placed from the left arm traverses
the left vertebral artery orifice, but not that of the left common carotid artery; this
may reduce the risk of stroke.
5. What are some complications unique to brachial access?
There is a small risk of stroke associated with brachial access. The arm cannot
tolerate large hematomas, and bleeding after removal of a catheter or sheath may
E
result in compartment syndrome. If a hematoma does develop, it must be followed
up carefully to ensure that neurovascular compromise does not occur. Surgical
F
evacuation of the hematoma may be required to prevent a neurologic deficit.
G H
6. What is claudication?
Claudication is derived from the Latin verb claudicare, which means  to limp.
Claudication describes exercise-induced leg pain secondary to peripheral vascular
Figure 32-1. Leg arterial vascular
disease (PVD). Patients with claudication typically complain of a burning or aching
anatomy. The arrow and blue
sensation in the thigh or calf, which starts after a predictable distance and remits
circle indicate the preferred site
with rest. With advanced disease, there may be progression to rest pain, skin
for percutaneous access to the
ulceration, and tissue loss.
common femoral artery, over the
middle third of the femoral head
(A = external iliac artery, B = femoral
7. What are the risk factors for PAD (Peripheral arterial disease)?
bifurcation, C = deep femoral artery,
Risk factors for claudication and PAD include hypertension, diabetes, high
D = superficial femoral artery,
cholesterol, cigarette smoking, and older age. Claudication is also more likely in
E = popliteal artery, F = anterior
individuals who already have atherosclerosis in other arteries, such as the coronary
tibial artery, G = peroneal artery,
or carotid arteries. H = posterior tibial artery).
235
C
H A P T E R
236 PERIPHERAL VASCULAR DISEASE
8. Does the location of leg pain suggest the location of arterial stenosis?
Leg pain usually occurs downstream to hemodynamically significant stenoses. Calf pain may result from disease of the
superficial femoral artery, whereas thigh or buttock pain may be caused by iliac disease.
9. What is Legs For Life?
Legs For Life is a national screening program initiated by the Society of Interventional Radiology (http://www.sirweb.org/)
that is dedicated to improving the cardiovascular health of the community. It is a public education/community wellness
program that screens people who may be at risk for PVD and helps them take the next step in resolving the pain they are
experiencing. The primary goals of the Legs For Life program are to educate the public, primary care physicians, and medical
community; identify patients at risk; and strengthen collaborative relationships among health care professionals who treat
this condition.
10. Why is it important to identify patients with claudication?
PVD affects more than 10 million Americans, and its prevalence is increasing. PVD is an important marker for many
other serious conditions, including coronary artery disease, cerebrovascular disease, aneurysms, diabetes, and
hypertension. Patients with PVD have a fourfold to sixfold increase in cardiovascular mortality compared with age-
matched controls. The mortality rate for patients with claudication may be 75% 15 years after diagnosis of PVD. Early
diagnosis of claudication gives patients the chance to modify their atherosclerotic risk factors and reduce their risk
of coronary and carotid artery disease.
Key Points: Peripheral Vascular Disease
1. Asymptomatic arterial lesions rarely require treatment.
2. Patients rarely die from PVD, but this disease serves as a marker for other, potentially life-threatening
processes, such as cerebrovascular disease and coronary artery disease.
3. PVD is underdiagnosed in women.
11. What is the Fontaine classification?
The Fontaine classification is a widely used classification system for lower extremity ischemia. It describes four stages
based on signs and symptoms.
" Stage 1 is asymptomatic disease.
" Stage 2a is intermittent claudication when walking more than 200 m.
" Stage 2b is intermittent claudication when walking less than 200 m.
" Stage 3 is rest pain.
" Stage 4 is tissue necrosis or gangrene.
12. What is the Rutherford-Becker classification system?
This is another classification system for chronic lower extremity ischemia. It is popular in the United States and is based
on clinical and objective criteria (Table 32-1).
Table 32-1. Rutherford Becker Classification System
GRADE CATEGORY CLINICAL DESCRIPTION OBJECTIVE CRITERIA
0 0 Asymptomatic Normal treadmill/stress test
1 1 Mild claudication Complete treadmill test, ankle pressure
after exercise <25-50 mm Hg less than
blood pressure
2 Moderate claudication Between categories 1 and 3
3 Severe claudication Cannot complete treadmill test, ankle
pressure after exercise <50 mm Hg
2 4 Rest pain Resting ankle pressure <40 mm Hg, flat
or barely pulsatile ankle or metatarsal
pulse volume recording
3 5 Minor tissue loss, nonhealing Resting ankle pressure <60 mm Hg
6 Major tissue loss, functional Same as category 5
foot no longer salvageable
INTERVENTIONAL RADIOLOGY 237
13. What are the clinical categories of leg ischemia?
The clinical categories of leg ischemia are presented in Table 32-2.
Table 32-2. Clinical Categories of Acute Leg Ischemia
CAPILLARY MUSCLE SENSORY ARTERIAL VENOUS
CATEGORY DESCRIPTION RETURN WEAKNESS LOSS DOPPLER DOPPLER
Viable Not immediately Intact None None Audible Audible
threatened (ankle
pressure
>32 mm
Hg)
Threatened Salvageable Intact, but Mild, partial Mild, Inaudible Audible
if treated slow incomplete
promptly
Irreversible Major tissue loss, Absent Profound Profound, Inaudible Inaudible
amputation (marbling) paralysis, anesthetic
indicated rigor
regardless of
treatment
14. What is the ankle-brachial index (ABI)?
The ABI is an essential component used for risk stratification for PVD. The ABI is used to screen for hemodynamically
significant disease and to help define its severity. With the patient in the supine position, bilateral brachial blood
pressures are obtained. A blood pressure cuff is placed on the calf of each leg, and an ankle systolic pressure is
obtained. Determining ankle systolic pressure may require the use of Doppler. The ABI is calculated by dividing the ankle
systolic pressure by the highest systolic pressure from either arm.
15. How is the ABI interpreted?
A normal ABI is slightly greater than 1. A significant obstruction to blood flow to the lower extremities reduces
the ankle pressure and the ABI. The risk of PVD and symptoms increases as the ABI decreases (Tables 32-3
and 32-4).
Table 32-3. Ankle-Brachial Index (ABI) by Symptoms
ABI SYMPTOMS
1-1.10 Normal
0.3-0.9 Claudication
d"0.5 Rest pain
d"0.2 Tissue loss
Table 32-4. Ankle-Brachial Index (ABI) by Risk
ABI CATEGORY
e"1 Normal (no/low risk)
0.90-0.99 Borderline (probably normal; no/low risk)
0.70-0.89 Mildly abnormal (low/moderate risk)
0.50-0.69 Abnormal (moderate/high risk)
<0.49
16. What can cause a falsely elevated ABI?
The ability to determine the systolic blood pressure accurately is predicated by the ability to compress the artery
and obstruct blood flow. Diabetes may cause significant calcification of peripheral vessels, making them difficult to
compress; this would factiously elevate the observed cuff pressure and the calculated ABI.
238 PERIPHERAL VASCULAR DISEASE
17. What is meant by the terms inflow and outflow?
At least two criteria must be met for an artery to remain patent. There must be sufficient flow of blood into the vessel.
With respect to the femoral artery, inflow vessels include the aorta, common iliac artery, and external iliac artery.
A stenosis of any of these vessels constitutes an inflow lesion. Even with perfect inflow, there also must be flow out
of a vessel for it to remain patent. With respect to the femoral artery, the popliteal, peroneal, anterior, and posterior tibial
arteries constitute outflow vessels.
18. What are the basic steps in performing an angioplasty?
A thorough diagnostic arteriogram is performed first. This is important so that the lesion can be sized, and an
appropriate balloon can be selected. The patient is then given heparin. It is important to give heparin before crossing
the lesion to prevent thrombosis. The next step involves crossing the lesion with a catheter and guidewire. The lesion is
then dilated. After the balloon is removed, an arteriogram is performed with the wire across the lesion to evaluate the
result of the angioplasty. It is important to leave the wire in place until the follow-up arteriogram is performed in case
a complication, such as a flow-limiting dissection or arterial rupture, occurs.
Key Point: Angioplasty
1. Outflow is a key determinant for the long-term patency of angioplasty.
19. What constitutes a technically successful angioplasty?
" Restoration of luminal diameter with less than 32% residual stenosis
" A pressure gradient less than 5 mm Hg across the lesion
" Absence of a flow-limiting dissection or vessel rupture
" Relative reduction in the number and caliber of collateral vessels after a venous angioplasty
20. What are the complications of angioplasty?
The type and incidence of complications vary with the location and morphology of the lesion. Complications include
spasm, flow-limited dissection, plaque embolization, vessel rupture, access site trauma, renal dysfunction, contrast
allergy, and death.
21. What are the indications for stenting?
Primary indications for stenting include failed angioplasty caused by a flow-limiting dissection or elastic recoil.
22. What constitutes a hemodynamically significant arterial stenosis?
A stenosis is generally considered significant if the luminal diameter is reduced by 50%, and the systolic pressure
gradient is greater than 10 mm Hg across the lesion. A lumen that is diminished by 50% would have a corresponding
75% reduction in cross-sectional area, which would likely reduce flow to a clinically significant level. In patients with
claudication and lesions that are equivocal based on the aforementioned criteria, provocative testing may be performed.
Tolazoline (Priscoline), a potent arterial dilator, is no longer commercially available. One may stimulate arterial dilation
with a prolonged inflation of a blood pressure cuff above the systolic pressure. A gradient greater than 20 mm Hg after
dilation is considered significant. One should remember to treat the patient and not the arteriographic or pressure
findings. The clinical history is also important in deciding whether a lesion is significant. There are few reasons to treat
a patient with an entirely asymptomatic lesion.
23. What is the kissing balloon technique?
This technique is most commonly used to perform angioplasty of the common iliac arteries (Fig. 32-2). Often, stenoses
of the proximal common iliac arteries are associated with large, eccentric, calcified plaques. Sequential as opposed to
simultaneous angioplasty may displace the plaque and lead to compromise of the contralateral iliac artery. The kissing
technique mitigates this risk through the use of simultaneous angioplasty. This requires bilateral retrograde femoral artery
access. The kissing technique may be used for the dilation of complex bifurcation stenosis in other locations as well.
24. What are the basic principles in performing a thrombolysis procedure?
Thrombolysis therapy consists of the delivery of a lytic agent directly into a thrombosed vessel or graft. The catheter
is largely responsible for the specificity of the lysis. The immediate goal of the procedure is to lyse an unwanted
clot while preventing a systemically lytic state to minimize bleeding complications. The secondary goal of a thrombolysis
procedure is to uncover the cause of the thrombosis. Commonly, bypass grafts and native vessels thrombose because
of stenoses in inflow vessels, anastomoses, or outflow vessels. Unless the underlying cause for the thrombosis is
treated, thrombosis is likely to recur. Less commonly, there are instances in which grafts or vessels thrombose without
underlying stenoses. Embolic disease, diminished cardiac output, and noncompliance with anticoagulation therapy are
some causes of thrombosis in the absence of an underlying stenosis.
INTERVENTIONAL RADIOLOGY 239
25. In general, how is a thrombolysis
procedure performed?
A thorough history and physical examination of the
patient are performed. Particular attention should be
given to any prior surgeries described in the history.
Understanding the patient s vascular anatomy is key for
planning access and intervention. Prior arteriograms, if
available, should be reviewed. These may also help in
the planning of the access site and in determining an
appropriate end point to the procedure. A baseline physical
examination is essential to monitoring the patient s
progress or deterioration during the procedure. After
AB
laboratory findings are reviewed and consent has been
obtained, a thorough diagnostic arteriogram is performed.
The patient is given heparin, and a sheath is placed. The
thrombosis is crossed with a wire, and an infusion catheter
is placed across the clot. Lytics are infused through the
catheter, and the patient is sent to the intensive care unit
for monitoring. Every 12 to 24 hours, the patient is brought
back to the interventional suite for a follow-up arteriogram.
When the clot has resolved, the underlying lesion is
treated.
26. What is the guidewire traversal test?
The guidewire traversal test is an attempt to pass a
guidewire across a thrombosed vessel before lysis. If the
wire can be successfully passed across the occlusion, the
CD
clot is more likely to be fresh and lyse. If the guidewire
Figure 32-2. Kissing balloon technique. A, Bifurcation
traversal test fails, the occlusion is more likely to be chronic
lesion. B, Sequential angioplasty risks occlusion of the
and less responsive to lytics. An end-hole catheter, positioned
unprotected vessel. C, Simultaneous angioplasty prevents
proximal to the clot, may be used to deliver lytics and soften
plaque displacement. D, Desired result.
the clot to facilitate wire traversal. When a wire has been
passed, an infusion catheter can be placed. Placement of an
infusion catheter within the bulk of the clot helps lend specificity to the lysis procedure and may reduce the overall time
required for lysis.
27. List the contraindications to thrombolysis.
" Absolute : Active internal bleeding, known intracranial pathology, stroke within the past 6 months, craniotomy in the
past 2 months, irreversible limb ischemia, and infected bypass graft
" Relative: Uncontrollable hypertension, history of gastrointestinal bleeding, bacterial endocarditis, diabetic
retinopathy, coagulopathy, pregnancy, recent major surgery, recent major trauma, and recent cardiopulmonary
resuscitation.
In patients with relative contraindications, it is imperative to analyze the potential risk-to-benefit ratio carefully in each
case.
28. What is a PVR examination?
PVR stands for pulse volume recording, and it is a noninvasive method to evaluate arteries of the lower extremity.
A brachial pressure and arterial waveform are obtained as reference standards. The process is repeated at different
stations, including the high thigh, low thigh, calf, ankle, and foot. The segmental pressures and waveforms are analyzed
to identify the level and severity of possible stenoses. Arterial waveforms provide especially useful information in the
setting of calcified vessel. This test is one way that surveillance may be performed after a vascular intervention. It can
also be used to plan an intervention in a symptomatic patient.
29. What is Leriche syndrome?
Leriche syndrome comprises chronic, lower extremity ischemia resulting from aortoiliac obstruction that is characterized
by intermittent buttock claudication, absent femoral pulses, and sexual impotence (Fig. 32-3).
30. What is an ACT measurement?
ACT stands for activated clotting time. It is a clotting test that may be performed in the interventional suite and is
commonly used to monitor the effect of heparin. A small sample of whole blood is placed in the testing machine,
and a result is available in less than 5 minutes. The reference range varies considerably, but it is usually 70 to
240 PERIPHERAL VASCULAR DISEASE
180 seconds. Although it can be obtained quickly, ACT is less
precise than partial thromboplastin time and can be affected by
a host of factors, including ambient temperature, platelet count,
and hemodilution.
31. How are groin pseudoaneurysms managed?
Pseudoaneurysms resulting from femoral artery puncture
can be managed in several ways, based on the patient s
clinical status and the anatomy of the lesion. The first
A
step is recognizing that the complication has occurred.
A postprocedure groin check may reveal a pulsatile mass or
ecchymosis. The patient may complain of groin pain. US can be
used to diagnose or exclude the injury. If a pseudoaneurysm is
found, several options exist. Manual or US-guided compression
may cause the pseudoaneurysm to thrombose. Direct thrombin
injection can also be performed if the anatomy of the lesion
is suitable. Surgical intervention is also an option if other
techniques fail.
32. What are the major pathways of collateral
circulation to supply the lower extremities in a
patient with known aortic occlusion?
D
A simple way to help remember the collateral supply is to divide it
into anterior, middle, and posterior pathways:
E " Anterior : Subclavian artery through the internal mammary to
the superior epigastric artery to the inferior epigastric artery
and then into the external iliac artery
" Middle : Superior mesenteric to the inferior mesenteric
C B
artery via the arc of Riolan and the marginal artery of
Drummond to the superior and inferior hemorrhoidal arteries
Figure 32-3. Collateral vascular pathways in aortic
to the internal iliac arteries and then to the external iliac
occlusion. Anterior supply: Left subclavian artery to left
external iliac artery, via internal mammary and inferior arteries
epigastric arteries (A). Middle supply: Inferior mesenteric
" Posterior : Lumbar arteries to the internal iliac arteries via
artery to internal iliac artery (B ). Posterior supply: Median
the retroperitoneal collaterals and then to the external
sacral artery to internal iliac artery (C). Lumbar artery to
iliac arteries by way of the iliolumbar and circumflex iliac
internal iliac artery (D ). Lumbar artery to external iliac
arteries
artery (E ).
WEBSITE
http://www.legsforlife.org
BIBLIOGRAPHY
[1] M.J. Pentecost, H. Michael, G.D. Criqui, et al., Guidelines for peripheral percutaneous transluminal angioplasty of the abdominal aorta and
lower extremity vessels: a statement for health professionals from a special writing group of the Councils on Cardiovascular Radiology,
Arteriosclerosis, Cardio-Thoracic and Vascular Surgery, Clinical Cardiology, and Epidemiology and Prevention, the American Heart
Association, J. Vasc. Interv. Radiol. 14 (2003) 495S 515S.
[2] D. Sacks, C.W. Bakal, P.T. Beatty, et al., Position statement on the use of the ankle brachial index in the evaluation of patients with
peripheral vascular disease: a consensus statement developed by the Standards Division of the Society of Interventional Radiology,
J. Vasc. Interv. Radiol. 14 (2003) 389S.