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Diagnostic Evaluation ofArterial
Disease inLimb Salvage
MichaelSiah andCameronM.Akbari
20
Introduction
Many studies have established the association
between diabetes mellitus and peripheral arterial
disease (PAD). Although atherosclerosis is a generalized process that can occur in diabetics and
non-diabetics alike, the prevalence of PAD is
more common in diabetic patients. In patients
with diabetes, for every 1% increase in hemoglobin A1c, there is a 26% associated increase in the
risk of PAD [1]. In fact, PAD in conjunction with
diabetic neuropathy contributes to 50% of diabetic foot ulcerations [2].
The predominant arterial beds impacted by
PAD in the diabetic patient are typically infrageniculate, or below the knee. The pathophysiologic mechanism of disease of the anterior tibial,
posterior tibial, peroneal, dorsalis pedis, and
geniculate arteries is most frequently medial cal-
M. Siah (*)
Surgery, University of Texas Southwestern Medical
Center, Dallas, TX, USA
Clements University Hospital, Dallas, TX, USA
Parkland Memorial Hospital, Dallas, TX, USA
e-mail: michael.siah@utsouthwestern.edu
C. M. Akbari
Surgery, Georgetown University Medical School,
Washington, DC, USA
Vascular Surgery, Medstar Georgetown University
Hospital, Washington, DC, USA
e-mail: cameron.akbari@medstar.net
cinosis [3]. Below the ankle, the infra-malleolar
and pedal arch vessels may be impacted by nonenzymatic glycation due to elevated blood sugar
[4]. Disease in any vascular bed may impact
wound healing. For example, even an incomplete
pedal arch is associated with recurrent ulceration
within 1 year after primary ulcer healing [5].
These implications highlight the importance of
vigilant perfusion screening in both symptomatic
and asymptomatic diabetic patients to improve
the healing of and prevent new and recurrent
ulcerations.
History andPhysical Examination
Perfusion assessment of the diabetic patient
begins with a complete history and careful physical examination. It should include gross examination of the patient for the stigmata of peripheral
vascular disease. Broadly classied, this bedside
assessment includes the healing potential of the
foot, the details of the foot problem (e.g., ulcer,
gangrene, infection, osteomyelitis, etc.), the systemic consequences of diabetes, and any immediate threats to life and/or limb. By carefully
following these considerations, the astute surgeon can usually make an accurate diagnosis and
reliably start a comprehensive treatment plan
without the need for further costly and timeconsuming diagnostic tests.
© Springer Nature Switzerland AG 2023
C. E. Attinger, J. S. Steinberg (eds.), Functional Limb Salvage,
https://doi.org/10.1007/978-3-031-27725-2_20
251
252
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M. Siah and C. M. Akbari
The history of the foot problem itself can give
valuable insight as to the potential for healing,
the presence of coexisting infection or arterial
occlusive disease, and the need for further treatment. Any patient presenting with a foot ulceration or gangrene should immediately arouse
suspicion of underlying arterial insufciency,
even if neuropathy or infection is present. In the
patient with diabetes and arterial insufciency,
the inciting event for a nonhealing foot ulcer may
be a seemingly benign event such as cutting a
toenail, soaking the foot in a warm bath, or a
heating pad.
The duration of the ulcer also provides important clues, insofar as a long-standing, nonhealing
ulcer is strongly suggestive of ischemia.
Certainly, an ulcer or gangrenous area that has
been present for several months is unlikely to
heal without some type of further additional
treatment, whether it be off-loading of weightbearing areas, treatment of infection, or, most
commonly, correction of arterial insufciency.
Did the present ulcer heal previously, and is the
present episode a relapsing problem? A history of
intermittent healing followed by relapse should
raise suspicion of underlying untreated infection,
such as recurrent osteomyelitis, or uncorrected
architectural abnormality, such as a bony pressure point or varux deformity.
It is helpful to consider past opinions and
treatments, while still formulating an objective
treatment plan based on presenting data. Many
diabetic patients with correctable foot ulceration
and limb ischemia have been told that the only
option is limb amputation, usually due to “inherited pessimism” and inadequate knowledge of
the advances made in limb and foot salvage. In
these circumstances, when sought for an additional treatment opinion, it is best to “start at the
beginning” rather than blindly concur with previous actions.
The past history should be rst directed to previous foot and limb problems. Recent ipsilateral
ulceration or foot surgery that healed in a timely
and uncomplicated course may suggest adequate
arterial supply; with a more remote history, however, such information becomes less useful. A
history of previous leg revascularization (including percutaneous therapies) also provides an
important clue as to underlying arterial insufciency. Other cardiovascular risk factors, such as
cigarette smoking or hyperlipidemia, should also
be considered, as their presence increases the
likelihood that ischemia is contributing to the
present foot problem.
Although claudication or rest pain has traditionally been associated with vascular disease,
diabetic neuropathy may obscure those symptoms, and their absence in the diabetic patient
certainly does not rule out ischemia. Because
even moderate ischemia will preclude healing in
the diabetic foot, the absence of rest pain is not a
reliable indicator of adequate arterial blood supply; moreover, many patients may not ambulate a
sufcient distance to develop true vasculogenic
claudication. Conversely, some patients with true
ischemic rest pain are dismissed for years as having “painful neuropathy.”
Because unrecognized infection in the diabetic patient may rapidly progress to a lifethreatening condition, attention should be
directed toward detecting the subtle manifestations of an infected foot ulcer. Worsening hyperglycemia, recent erratic blood glucose control,
and higher insulin requirements all suggest
untreated infection. Due to the microvascular and
neuropathic abnormalities in the diabetic foot,
classical symptoms of infection such as chills or
pain are often absent, and hyperglycemia is often
the sole presenting symptom of undrained infection. With ongoing infection and hyperglycemia,
impending ketoacidosis or nonketotic hyperglycemic hyperosmolar coma may develop, with
symptoms of weakness, confusion, and altered
mental status.
The history should also include a comprehensive assessment of the patient’s overall health, to
help stratify perioperative risk should some type
of operative intervention be needed. Knowledge
of previous cardiac events, such as myocardial
infarction or revascularization, and present cardiac status, anginal severity, and heart failure
symptoms are all mandatory components of the
history taking. Similarly, in the patient with suspected infection and ischemia, a history of worsening renal function or impending need for
hemodialysis will help determine the dose and
choice of antibiotics and may alter plans for stan-
20 Diagnostic Evaluation ofArterial Disease inLimb Salvage
253
dard contrast arteriography. Functional status
also becomes an important consideration at this
point, and the history should carefully determine
the ambulatory and rehabilitative potential of the
patient, so that appropriate decisions may be
made for limb salvage or amputation.
Examination of each limb should identify
scars indicating healed arterial or venous ulcers,
prior surgical interventions such as saphenous
vein harvesting or distal bypass, and biomechanical callous formation. Trophic skin lesions such
as pale, cool skin or shiny, thickened nail beds
may be visible. Hair loss is an unreliable sign of
ischemia and is of little clinical value [6].
Capillary rell in the soft tissue or under the nail
bed should be assessed. Atrophy, pallor, and
asymmetric peripheral temperatures should be
noted. Ulcerations and areas of necrosis or gangrene should be described, measured, and
photographed.
The pulse examination, including the status of
the foot pulses, is the single, most important
component of the physical exam and remains as a
cornerstone in the treatment algorithm. As has
been emphasized, ischemia is always presumed
to be present in the absence of a palpable pulse.
Identication of diminished or absent pedal
pulses provides a general indication as to the
presence and level of atherosclerotic disease burden. For example, a palpable popliteal pulse in
the setting of absent pedal pulses suggests isolated tibial disease whereas an absent popliteal
pulse may suggest a more proximal disease burden. Regardless of the level of disease, the UK
NICE National Guidelines for the diabetic foot
suggest that the absence of palpable pedal pulses
is sufcient for the identication of vascular
impairment [7]. Any atherosclerotic disease
resulting in the loss of a pulse may cause inadequate perfusion for wound healing [3].
Although not difcult, an accurate pulse
examination of the lower extremities is an
acquired skill, and time should be devoted to
practicing and perfecting the technique. The femoral pulse is palpated midway between the superior iliac spine and the pubic tubercle, just below
the inguinal ligament. The popliteal pulse should
be palpated with both hands and with the knee
exed no more than 15° (Fig.20.1).
Great attention should be directed toward the
foot pulses, which requires a knowledge of the
usual location of the native arteries. The dorsalis
pedis artery is located between the rst and second metatarsal bones, just lateral to the extensor
hallucis longus tendon, and its pulse is palpated
by the pads of the ngers as the hand is partially
wrapped around the foot (Fig.20.2).
If the pulse cannot be palpated, the ngers
may be moved a few millimeters in each direction, as the artery may have an occasional slight
aberrant course. A common mistake is to place a
Fig. 20.1 Proper technique for the palpation of a popliteal pulse
Fig. 20.2 Palpation of the right dorsalis pedis artery
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M. Siah and C. M. Akbari
single nger at one location on the dorsum of the
foot. The posterior tibial artery is typically
located in the hollow just behind the medial malleolus, approximately halfway between the malleolus and the Achilles tendon. The examiner’s
hand should be contralateral to the examined foot
(i.e., the right hand should be used to palpate the
left foot and vice versa), so as to allow the hand
curvature to follow the ankle (Fig.20.3).
There are many published scales that may aid
in the standardization of physical exam reporting.
Consistent use allows for the clinician to track
patient improvement or decline. The Fontaine and
Rutherford classications, as well as the
University of Texas system, have historically been
used to guide wound assessments; however each
do not incorporate all the etiologies of threatened
Fig. 20.3 Palpation of the right posterior tibial artery
limbs. The presence of infection and involvement
of deeper structures increases the metabolic
requirement of ulcer healing [8]. To account for
this, the Society for Vascular Surgery devised the
WI System to better predict amputation risk and
better evaluate outcomes in the treatment of
peripheral vascular disease. By integrating the
key factors associated with tissue loss, the WI
classication system is able to combine perfusion
and tissue assessment to better predict clinical
outcomes than previous scoring systems.
Ultimately, the use of any of these scoring systems allows for objective assessment of patients
that can guide care and monitor outcomes.
Noninvasive Perfusion Assessment
Noninvasive testing is benecial in both the diagnosis of existing peripheral vascular disease and
in screening patients for advancing atherosclerotic
disease. The simplest of noninvasive exam that can
be performed is the ankle-brachial index (ABI)
(Fig.20.4). It is a critical extension of the vascular
physical exam and can be performed by the clinician at the bedside. The ABI is a ratio of the ankle
and brachial systolic blood pressures. A normal
ABI can range from 0.9 to 1.2 [10]. Generally,
an ABI of >0.8 is not associated with impaired
wound healing [11]. Given the ease with which
an ABI can be performed, the American Diabetes
Association recommends PAD screening with an
ABI every 5years in patients with diabetes [12].
Unfortunately, ABI values can often be unreli-
able in the diabetic patient due to the extensive
Fig. 20.4 Bedside technique for performed ankle pressure measurement using a Doppler probe at the (a) posterior
tibial artery and (b) dorsalis pedis artery [9]
20 Diagnostic Evaluation ofArterial Disease inLimb Salvage
255
calcication, or medial calcinosis, of the infrapopliteal blood vessels. This extensive calcication prevents proper compression of the tibial
arteries and results in either a falsely elevated ABI
or a value that is unattainable due to the inability
to achieve a vessel compression at a supra-systolic cuff pressure. Therefore, any abnormal, be
it diminished or falsely elevated (non-compressible), ABI indicates the presence of arterial disease that should be further evaluated.
When ABIs are impaired or unattainable, a
vascular lab can provide other useful diagnostic
tests to assess perfusion in the diabetic patient.
Pulse volume recording (PVR), also known
as plethysmography, is a noninvasive method
to evaluate the arteries of the lower extremity.
The pulsed volume recorder (PVR) is a form of
volume plethysmography, which measures the
pulsatile volume changes that occur in the limb
with each heartbeat. A pneumatic cuff is placed
around a specic level of the limb (thigh, calf,
and ankle) and inated with air to a preset pressure between 10 and 65mmHg. During systole,
blood enters the limb, the limb expands, this
expansion presses upon the cuff, and the pressure
within the cuff increases. During diastole, limb
volume is reduced and cuff pressure falls. Therefore, volume changes within a specic level of
the limb beneath the cuff are indirectly studied by
measuring pulsatile pressure changes within the
cuff. These changes are converted into a waveform by a strip recorder.
The normal PVR waveform displays a brisk
rise during systole, a sharp systolic peak, a
dicrotic notch, and a rapid downslope to baseline.
Segmental pressures and waveforms are analyzed to identify the level and degree of potential
stenosis. Pressure cuffs are used to measure the
pulsatile change in blood pressure at various levels of a limb (Fig.20.5). Abnormal PVR ndings
include decreased amplitude, a attened peak,
and an absent dicrotic notch. Amplitudes of less
than 5mm from trough to peak have been used as
a criterion for the diagnosis of peripheral vascular disease [13].
Because the PVR measures volume change
and not pressure, it is also unaffected by noncompressible arteries and may be a valuable adjunct
in the evaluation of the diabetic foot. However,
as with all noninvasive tests, the PVR has several
limitations. Although there are some semiquantitative criteria, these have not been correlated
clinically, and the test is essentially qualitative.
Therefore, a completely normal study is helpful, but it is difcult to quantitate the degree of
ischemia with any abnormal study. Indeed, one
major shortcoming of the PVR test is that it frequently underestimates the severity of proximal
arterial disease (due to the presence of collateral
vessels). Additionally, the test is affected by several variables, including room temperature (since
temperature differences in the air cuff can change
the pressure measured by the air-lled plethysmograph). Peripheral edema and obesity will also
affect the quality of the waveforms.
Toe systolic pressure measurements (TSP)
and transcutaneous partial oxygen pressure measurements (TcPO2) are useful modalities to attain
a better understanding of tissue perfusion. Transcutaneous oxygen tension measurements reect
the resting oxygen tension (and the metabolic
state) of the underlying tissue. The test involves
the placement of a probe (with a sensitized electrode) on the dorsum of the proximal foot, and
the local tissue is heated to about 40–42°C.Following an equilibration period of 20–25 min,
the local resting oxygen tension of the skin is
recorded in mm Hg. The measurement of toe
pressures allows for an accurate assessment of
pedal perfusion as digital vessels are often free
of atherosclerotic disease burden. Toe pressures
are usually 30 mmHg less than ankle pressures
and an abnormal toe-brachial index (TBI) is
<0.70 [14]. However, digital ulceration or prior
amputation may limit the usefulness of the TBI
examination.
Transcutaneous measurement (TcPO2) of
the partial oxygen pressure is performed at the
back of the foot and between the rst and second
toe space. Normal TcPO2 for a diabetic patient
is 50 mmHg [15]. Because hemodynamics are
not measured, the test is immune to many of
the problems facing other noninvasive tests
in the presence of diabetes, such as noncompressible vessels. However, due to the unique
considerations of the diabetic foot, TcPO2
measurements are not entirely reliable in the
diabetic patient with foot ulceration. Lockhart
256
Doppler
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M. Siah and C. M. Akbari
R) Femoral
Gain: 18%
R) Sup Femoral
Gain: 18%
R) Popliteal
Gain: 24%
R) Post Tibial
Gain: 24%
R) Dors: Pedis
L) Femoral
Segmental BP
Segment/Brachial Index
RL
148
Brachial
150
Gain: 24%
L) Sup Femoral
Gain: 24%
L) Popliteal
Gain: 24%
L) Post Tibial
100 (PT) (PT) 96
0.67 0.64
99 (DP)
0.66
(DP) 99
Gain: 24%
L) Dors: Pedis
0.66
30
Gain: 24%
R) Digit
Gain: 85% Amp; 1mm Amp; 3mm
0.20
0.67
Ankle/Brachial Index
TBI
0.53
0.66
80
Gain: 85%
L) Digit
Gain: 85%
Fig. 20.5 Physiologic study demonstrating segmental pulse volume recording associated with an aortic occlusion
etal. demonstrated pressures <30mmHg to be
associated with severe ischemia, while pressures
>40 mmHg are associated with wound healing
with conservative therapy [16, 17]. Additionally, Kalani etal. demonstrated that TcPO2 can
be a better predictor for ulcer healing than toe
pressures in diabetics with foot ulcerations and
conrmed a low likelihood of wound healing
with pressures <25mmHg [18]. Therefore, the
likelihood of wound healing increases with skin
perfusion pressures of >40mmHg, toe pressures
>30mmHg, or TcPO2 >25mmHg [19]. Values
below these levels suggest a role for invasive
diagnostic and therapeutic measures. It should
be noted, though, that despite the documented
utility of skin perfusion pressure measurements
20 Diagnostic Evaluation ofArterial Disease inLimb Salvage
257
and TcPO2, they are not typically performed.
Even in the patient with a “normal” TcPO2 value,
the measurement may not accurately reect the
healing potential at the target area. TcPO2 measurements may be inuenced by many technical
features, including the type of equipment used,
monitor placement, and surface temperature of
the measured area.
Hyperspectral Imaging (HSI) has emerged
as an additional noninvasive way to assess tissue perfusion and may have a role in predicting wound healing in diabetic patients with
tissue loss. HSI identies tissue oxygenation
on a microvascular level and anatomically
demonstrates changes in the microcirculation
(Fig.20.6). Unlike TpCO2, HSI measurements
Fig. 20.6 Visual hyperspectral images of pedal perfusion in a foot with no peripheral vascular disease (left) and a foot
with peripheral vascular disease (right) [20]
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can be performed quickly in the clinic. Additionally, HSI can directly evaluate perfusion
in the ulcer bed. One of the major barriers to
widespread application of the technology is
cost, as the devices are generally very expensive. Additionally, at present time, there is a lack
of evidence demonstrating the reliability of HIS
measurements in diabetics with tissue loss.
Noninvasive Diagnostic Imaging
Of the many modalities available to assess the
arterial supply of the lower extremity, the most
commonly utilized are duplex ultrasound, computed tomography angiography (CTA), and magnetic resonance angiography (MRA). In general,
these imaging tests should be reserved for
patients prior to or after endovascular or surgical
therapy. Ultrasound may be considered as the
rst-line study given its low cost and the lack of
potentially adverse side effects.
Duplex scanning employs the dual modalities of B-mode (gray scale) imaging and pulsed
wave Doppler spectral frequency analysis. In
addition, most Duplex scanners are actually
“triplex,” with the third modality being color
ow imaging. The vessel being insonated may
be localized by B-mode imaging, and the pulsed
wave Doppler allows for range specicity. Color
ow imaging evaluates the Doppler information
and determines whether ow is toward or away
from the transducer as well as frequency
content.
The information obtained from Duplex arterial scanning includes the gray scale ultrasound
structural characteristics of the artery (such as
wall thickness or type of plaque), as well as
Doppler waveform, velocities, and direction of
ow. Analysis of the Doppler waveform characteristics is similar to the preceding discussion on
segmental waveform analysis (considered as triphasic, biphasic, or monophasic), but the principal advantage of Duplex is that the vessel may be
localized by the gray scale ultrasound. Duplex
also allows for an estimation of the degree of stenosis based on velocities and degree of spectral
broadening: as an artery narrows, there will be a
velocity increase in the stenosis with spectral
broadening.
Despite the invaluable role of Duplex ultrasound in the diagnosis of carotid arterial disease
and for postoperative graft surveillance, there are
multiple limitations in its use for the diagnosis of
lower extremity arterial disease. There is a large
variation in the range of “normal” velocities for
the leg arteries, and therefore a signicant stenosis may be misinterpreted. Although the femoral
and popliteal vessels may be visualized relatively
easily, the tibial vessels are more cumbersome to
scan, and the velocities in the tibial arteries may
be even more difcult to interpret. When one
considers the usual pattern of vascular disease in
diabetes (with a predilection toward atherosclerotic involvement of the tibial vessels), the limitations of Duplex in the diagnosis of arterial
insufciency in the diabetic patient are realized.
Because the study depends on accurate sonographic localization of the vessel, Duplex is quite
“operator dependent.” Finally, multiple other
variables can inuence the quality of the image,
including medial arterial calcication (which can
cause artifactual shadowing), obesity, and peripheral edema (which can preclude imaging of the
tibial vessels).
In patients in whom ultrasound is unlikely to
be successful, particularly patients that have morbid obesity or extensive dressings or tissue loss,
CTA and MRA are reasonable second-line
imaging modalities. Both CTA and MRA allow
for visualization of supra-inguinal blood vessels,
for the localization of infra-inguinal disease burden and the characterization of stenotic or occlusive lesions. Most importantly, they can show the
quality of tibial runoff, which is vital for deciding
between different interventional strategies. A
CTA can be performed rapidly and allows for
easy evaluation of previously placed stents and
bypasses. However, in the setting of severe calcication, CTA may overestimate the degree of stenosis and lack accuracy of ow assessment of the
tibial arteries. Additionally, CTA requires radiation exposure and the use of iodinated contrast
agents for vasculature visualization. Such agents
are contraindicated in patients with underlying
renal dysfunction due to the risk of contrast-
20 Diagnostic Evaluation ofArterial Disease inLimb Salvage
induced nephropathy. However, they can be used
in patients with end-stage renal disease (ESRD).
MRA is useful in patients with mild renal dysfunction, as unlike CTA, MRA does not require
iodinated contrast. MRA uses a gadoliniumbased contrast agent to provide better visualization of the arterial system in the lower extremity.
Gadolinium contrast, however, has been associated with the development of nephrogenic systemic brosis in patients with impaired creatinine
clearance and is contraindicated in patients with
ESRD. MRA utilization may be limited in
patients with claustrophobia or metallic implants
and long acquisition times are associated with
more patient-generated motion artifact.
Ultimately, the selection between the use of
duplex, CTA, or MRA depends upon patientspecic factors, local expertise, and safety prole
and is up to the discretion of the clinician.
Invasive Diagnostic Imaging
259
Invasive diagnostic imaging in diabetics with
signs of tissue loss and ischemia should be limited to those patients who would not benet from
primary amputation. Arteriography is the best
means of identifying the distribution and extent
of PAD. Angiography allows for real-time ow
assessment using either carbon dioxide, iodinated contrast, or gadolinium contrast to visualize
arterial ow under uoroscopy. Arterial stenosis,
occlusive lesions, and named-vessel collateral
reconstitution may all be assessed (Fig. 20.7).
Diagnostic imaging may then translate into endovascular intervention or become the basis for
open surgical intervention.
Angiography also allows for angiosome characterization. Introduced nearly 30years ago, an
angiosome refers to a 3-dimensional unit of tissue comprised of skin, subcutaneous tissue, muscle, and bone, supplied by a clear arterial source.
In the lower leg and foot, there are six angiosomes: three fed by the posterior tibial artery, one
fed by the anterior tibial artery, and two supplied
by the peroneal artery. Attinger et al. have
demonstrated the validity of the angiosome concept in free ap procedures; however the data
Fig. 20.7 Diagnostic arteriogram revealing an occlusion
of the anterior tibial artery and a patent peroneal and posterior tibial artery
regarding the angiosome in diabetic patients with
PAD is less conclusive.
The clinical application of the angiosome concept requires an understanding of perfusion
sources of the foot and to consider these as therapeutic targets for intervention. Interventionalists
can perform angiosome-directed revascularization procedures, which focus on intervening on
the source vessel/angiosome of ulceration, as
opposed to indirect revascularization procedures.
Some studies have demonstrated more rapid
times to healing with angiosome-directed revascularization procedures; however there is no difference in amputation rates. Ultimately,
considering the option of angiosome-directed
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revascularization should be performed, however
revascularization should still be pursued indirectly if no direct revascularization targets are
available.
Given the challenge of correlating angiosome
and non-angiosome-based perfusion assessment
with clinical outcomes, the use of indocyanine
green angiography (ICGA) has also emerged as a
perfusion assessment tool. ICGA has been studied extensively in free ap creation and has been
shown to provide perfusion information that predicts tissue survival in assessing ap viability
[21–23]. ICG is administered intravascularly
where it binds to serum proteins. The uptake of
ICG can be quantied in tissue bed of interest
and this value may serve as a surrogate for tissue
perfusion. Ongoing studies are being performed
to determine the role of IGCA in determining the
optimal treatment of peripheral vascular disease,
as well as assessing the success of revascularization procedures [24, 25].
Therapeutic Options
There are two modalities to address perfusion
decits in diabetic patients with tissue loss: open
and endovascular surgery. Open techniques,
namely surgical bypass, historically have been
the mainstay of treatment. Bypass with autogenous conduit, most commonly the greater saphenous vein, represents the gold standard for
revascularization techniques, as it is associated
with better patency and increased amputation
free survival compared to bypass using prosthetic
conduits [26]. However, endovascular therapies
have emerged as an acceptable rst line in the
surgical management of ischemic diabetic foot
ulcerations. This is likely due to the ease with
which diagnostic and therapeutic procedures can
now be performed, as well as the wide variety of
interventionalists who are capable of performing
them.
Coming to a decision between bypass rst
versus an endovascular rst strategy is challenging due to the absence of randomized controlled
data demonstrating the superiority of either
modality in patients with diabetes. The BASIL
trial, a randomized controlled trial, compared the
results of angioplasty versus bypass and examined amputation rates and survival for the two
methods. There was no signicant difference
between the two techniques, but there was a
marked advantage of endovascular techniques in
patients with elevated surgical risk, and better
results than prosthetic bypasses. Additionally, the
trial suggested that bypass outcomes following
failed endovascular interventions were worse
than those performed prior to endovascular therapy. Since BASIL, there has been little randomized controlled data to guide clinical decision
making in the management of critical limb ischemia, but there has been a marked proliferation in
the endovascular tools available to the interventionalists. Newer wires, catheters, sheaths, and
other devices like drug eluting stents (DESs),
drug-coated balloons (DCBs), and atherectomy
devices have become readily available and have
made treating TASC C and D lesions much easier
than before [27–29]. These newer techniques are
frequently used to treat PAD despite an absence
of level one data. To address the lack of treatment
consensus in PAD management, the BEST-CLI
(Best Endovascular versus Best Surgical Therapy
for Patients With Critical Limb Ischemia) trial is
currently being conducted. This trial will compare outcomes of the best endovascular and open
surgical revascularization strategies in patients
with tissue loss and infrainguinal PAD.
Conclusion
Peripheral arterial disease in the diabetic patient
is a growing problem and will continue to represent a tremendous economic and social burden
facing modern societies in the twenty-rst century. Early recognition of perfusion decits is
critical in curtailing the extent of this problem,
and there are a variety of noninvasive tests that
allow for the objective identication of
PAD.Once diagnosed, referral to a vascular specialist allows for the restoration of arterial perfusion either by open or endovascular techniques.
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