Approach
Your Organizational Guidance
ebpracticenet urges you to prioritize the following organizational guidance:
Revascularisatie bij perifeer vaatlijden van de onderste ledematenPublished by: KCELast published: 2015Revascularisation en cas d’artériopathie périphérique du membre inférieurPublished by: KCELast published: 2015Peripheral arterial disease (PAD) is often under-recognized and undertreated.[3][7] Many patients with PAD are asymptomatic, but will have 1 or more risk factors.[2][3] The resting ankle-brachial index (ABI) is the initial diagnostic test for PAD.[2] It is recommended in all patients with suspected lower limb disease with a history of exertional leg symptoms, nonhealing wounds/foot ulcers, or abnormal lower extremity pulse exam. The toe brachial index (TBI) is useful in those patients where the ABI is unreliable (e.g., noncompressible arteries in patients with diabetes and advancing age, as well as in many renal patients on dialysis). Other tests used to establish diagnosis include:[2][43]
Segmental pressure examination
Duplex ultrasound
Pulse volume recording
Continuous wave Doppler ultrasound
Exercise ABI
Computed tomography angiography (CTA)
Magnetic resonance angiography (MRA)
Angiography
Patients at risk
Classic claudication symptoms occur in a minority of patients and it is reasonable to measure the ABI in people at increased risk of PAD but who have no history or physical exam. This includes people:[2]
Ages 65 years or older
Ages 50-64 years with risk factors for atherosclerosis (e.g., diabetes mellitus, history of smoking, hyperlipidemia, hypertension) or a family history of PAD
Who are less than 50 years old with diabetes mellitus and one additional risk factor for atherosclerosis
With known atherosclerotic disease in another vascular bed (e.g., coronary, carotid, subclavian, renal, mesenteric artery stenosis, or abdominal aortic aneurysm).
Other symptoms and signs
Further symptoms and signs may lead to a diagnosis of PAD in the presence of risk factors:
Calf or foot cramping with walking that is relieved with rest
Thigh or buttock pain with walking that is relieved with rest
Erectile dysfunction
Pain worse in one leg
Diminished pulse.
Critical limb ischemia should be suspected with the following:
Foot pain at rest
Gangrene
Nonhealing wound/foot ulcer
Muscle atrophy
Dependent rubor
Pallor when the leg is elevated
Loss of hair over the dorsum of the foot
Thickened toenails
Shiny/scaly skin.
Acute limb ischemia should be suspected with the following:[2]
The classic 6 signs of acute limb ischemia, which are pain, paralysis, paresthesias, pulselessness, poikilothermia, and pallor
Symptom duration less than 2 weeks.
Ankle-brachial index
An ABI should be performed in patients who have symptoms or answered positively to a review of questions regarding PAD.[44] An ABI ≤0.9 is diagnostic for the presence of PAD. The resting ABI should be used to establish the diagnosis of PAD in patients with exertional low-extremity claudication, rest pain, chronic limb ischemia, or nonhealing wounds/foot ulcers. It is an inexpensive and rapid office-based test.[2][3] ABI is performed by measuring the systolic pressure of the left and right brachial arteries and the left and right posterior tibial and dorsalis pedis arteries pressure. The ABI is the highest of the dorsalis pedis and posterior tibial arteries' pressure divided by the higher of the left and right arm brachial artery pulse pressure.
ABI may not be accurate in patients with noncompressible arteries, such as those with comorbid diabetes mellitus or chronic kidney disease (CKD), particularly those on dialysis. Patients with either severely stenotic or totally occluded arteries may also have normal ABI if there is abundant collateral system present.[44] Diagnosis of PAD should not be excluded based on normal or raised ankle-brachial pressure index alone in people with diabetes or CKD.[2][45] The ABI is a marker of peripheral atherosclerosis as well as a predictor of vascular events.[46]
Toe-brachial index
A TBI should be used to establish the diagnosis of PAD in patients in whom lower extremity PAD is clinically suspected, but in whom the ABI test is not reliable due to noncompressible vessels, such as in patients with comorbid diabetes or CKD, or those with advanced age. TBI should also be measured to diagnose patients with suspected PAD when the resting ABI is >1.40.[2]
Additional tests to help diagnose PAD
Evaluation of the arterial pressure waveform using pulse volume recording via pneumoplethysmography can add valuable information to the isolated ABI, particularly if the ABI is falsely elevated. Exercise ABIs are also a valuable adjunct. An exercise ABI does not provide information about the location of the lesion. It is useful, however, in establishing the diagnosis of lower extremity PAD in symptomatic patients when resting ABIs are normal or borderline.[2] Walking limitations can be measured with exercise ABI, along with the onset of symptoms, recovery time, and the total walking time.
Location and severity of PAD, using continuous wave Doppler ultrasound, is measured through a decrease in pulsatility index between adjacent proximal and distal anatomic segments.
Pulsatility index is calculated as Vmax - Vmin/Vmean, where:
Vmax = peak systolic velocity
Vmin = minimum diastolic velocity
Vmean = mean blood flow velocity.
Location and magnitude of stenosis can be determined with segmental pressure examination, based on pressure gradients between adjacent segments. Segmental pressure measurement may be artifactually elevated in patients with noncompressible arteries.
Further tests
Depending on the patient's symptoms, other diagnostic tests may be needed, including a more thorough assessment of the lower-extremity vasculature.[2][3] If the ABI/TBI is abnormal and symptoms warrant revascularization, the next test to guide the therapeutic decision is duplex ultrasonography of the lower-extremity arteries.[47] The duplex ultrasound is cost-effective and noninvasive, and should be done first to verify stenoses. This is most useful for counseling patients who may not have a minimally-invasive option to treat mild or moderate claudication.
Computed tomography angiography (CTA), magnetic resonance angiography (MRA), and catheter angiography can provide the anatomic detail necessary to determine a revascularization strategy and are appropriate initial investigations for patients presenting with acute limb ischemia but require intravenous contrast.[48] The spatial resolution of CTA and MRA may be lower than digital subtraction angiography.
The location and degree of stenosis can also be assessed by duplex ultrasound. This is the preferred and most widely used modality to assess stenoses.[47] The accuracy is diminished in tortuous, calcified prosthetic bypass grafts, and in vessels with multiple stenoses. In the aortoiliac arterial segment, accuracy can also be diminished due to bowel gas and body habitus.
Visualization of tissue surrounding the artery using CTA can demonstrate stenosis due to aneurysms, popliteal entrapment, or cystic adventitial disease that cannot be detected by angiography.
Revascularization can occur at the same time as catheter angiography. It is the only accepted modality and is considered the investigation of choice for assessing vascular anatomy and stenosis.
Anatomic location and stenosis can be diagnosed using MRA, although patients with pacemakers, defibrillators, and some cerebral aneurysm clips cannot be scanned safely. Gadolinium has caused nephrogenic systemic fibrosis in patients with chronic renal insufficiency.
Evaluation for comorbidities and risk enhancers
The presence of specific comorbidities and risk factors increases the risk for major adverse cardiovascular events and major adverse limb events in those with PAD, which may affect management choices. Evaluation of patients with PAD should include assessment for:[2]
Hypertension
Dyslipidemia
Diabetes
CKD/end-stage renal disease
Depression
Atherosclerotic disease in more than one vascular bed (PAD, coronary artery disease, cerebrovascular disease)
Microvascular disease (retinopathy, neuropathy, nephropathy)
Current smoking/tobacco use
Older age and geriatric syndromes (frailty, mobility impairment, sarcopenia, malnutrition)
Use of this content is subject to our disclaimer