ESC Guidelines on the diagnosis and treatment of peripheral artery ...

Page 24 of 56
In more severe cases pain is present at rest, in the supine position
(Fontaine stage III; Rutherford grade II). Rest pain is localized more
often in the foot and should be distinguished from muscle cramping
or arthritis. Patients often complain of permanent coldness in the
feet. Ulcers and gangrene (Fontaine stage IV; Rutherford grade III)
indicate severe ischaemia and begin mostly at the level of toes and
the distal part of the limb. Arterial ulcers are, in most cases, extremely
painful; they are frequently secondary to local trauma, even
minor, and should be distinguished from venous ulcers. When pain
is absent, peripheral neuropathy should be considered. Ulcers are
often complicated by local infection and inflammation.
Critical limb ischaemia is the most severe clinical manifestation
of LEAD, defined as the presence of ischaemic rest pain, and
Table 5 Clinical staging of LEAD
Fontaine
classification
Rutherford classification
Stage Symptoms Grade Category Symptoms
I Asymptomatic 0 0 Asymptomatic
II
III
IV
Intermittent
claudication
Ischaemic
rest pain
Ulceration or
gangrene
LEAD ¼ lower extremity artery disease.
I 1
I 2
I 3
II 4
III 5
III 6
Mild
claudication
Moderate
claudication
Severe
claudication
Ischaemic
rest pain
Minor tissue
loss
Major tissue
loss
<strong>ESC</strong> <strong>Guidelines</strong>
ischaemic lesions or gangrene objectively attributable to arterial
occlusive disease.
4.5.1.2 Clinical examination
Clinical examination can be quite informative both for screening
and for diagnosis. Patients should be relaxed and acclimatized to
the room temperature. Inspection may show pallor in more
severe cases, sometimes at leg elevation. Pulse palpation is very
informative for screening purposes and should be done systematically.
Pulse abolition is a specific rather than a sensitive clinical sign.
Auscultation of bruits over the femoral artery at the groin and
more distally is also suggestive, but poorly sensitive. The value of
the clinical findings in patients with LEAD can be strongly improved
by measuring the ABI. The blue toe syndrome is characterized by a
sudden cyanotic discolouration of one or more toes; it is usually
due to embolic atherosclerotic debris from the proximal arteries.
4.5.2 Diagnostic tests
4.5.2.1 Ankle–brachial index
The primary non-invasive test for the diagnosis of LEAD is the ABI.
In healthy persons, the ABI is .1.0. Usually an ABI ,0.90 is used
to define LEAD. The actual sensitivity and specificity have been
estimated, respectively, at 79% and 96%. 226 For diagnosis in
primary care, an ABI ,0.8 or the mean of three ABIs ,0.90
had a positive predictive value of ≥95%; an ABI .1.10 or the
mean of three ABIs .1.00 had a negative predictive value of
≥99%. 227 The level of ABI also correlates with LEAD severity,
with high risk of amputation when the ABI is ,0.50. An ABI
change .0.15 is generally required to consider worsening of
limb perfusion over time, or improving after revascularization. 228
For its measurement (Figure 2), a 10–12 cm sphygmomanometer
cuff placed just above the ankle and a (handheld) Doppler instrument
(5–10 MHz) to measure the pressure of the posterior and
anterior tibial arteries of each foot are required. Usually the
highest ankle systolic pressure is divided by the highest brachial systolic
pressure, resulting in an ABI per leg. Recently some papers
reported higher sensitivity to detect LEAD if the ABI numerator is
the lowest pressure in the arteries of both ankles. 229
Figure 2 Measurement of the ankle–brachial index (ABI), calculated by dividing the ankle systolic blood pressure by the arm systolic blood
pressure.