Peripheral Artery Disease

Preliminary Diagnosis: Peripheral artery disease

I. What imaging technique is first-line for this diagnosis?

• Ankle-brachial index (ABI) with segmental pressures and waveforms

II. Describe the advantages and disadvantages of this technique for diagnosis of Peripheral artery disease.

Advantages

• Simple to perform, well-tolerated, and cost-effective screening examination

• Segmental pressures help localize the level of disease

• Dampened waveforms help indicate the level of significant stenosis

Disadvantages

• Screening examination that does not provide anatomic detail for treatment planning

• May be limited in patients with heavily calcified vessels (often in diabetic patients)

• Abnormalities may not be present at rest (in these cases a treadmill test may be utilized to elicit symptoms)

III. What are the contraindications for the first-line imaging technique?

• No significant contraindications exist

IV. What alternative imaging techniques are available?

• Doppler US

• CT angiography

• MR angiography

• Angiography

V. Describe the advantages and disadvantages of the alternative techniques for diagnosis of peripheral artery disease.

Doppler US

Advantages

• The level of a low-resistive waveform can help localize the disease

• The lesion can often be directly visualized

• Peak systolic velocity can help determine if a lesion is hemodynamically significant

• Inexpensive and simple examination to perform

Disadvantages

• May not provide adequate anatomic detail for treatment planning

• May not be adequate to evaluate proximal inflow disease (especially in the presence of dense calcifications)

• Dependent on operator expertise

CT angiography

Advantages

• Accurately defines the level of disease and may help characterize the nature of plaque

• Can detect stenosis and occlusions as well as adjacent nonvascular pathology

• Detailed images are useful for treatment planning

Disadvantages

• Requires intravenous contrast, which may result in contrast-induced nephropathy

• Poor evaluation in the presence of extensive calcified plaque

• Bolus timing must be appropriate to avoid artifact

• Exposure to ionizing radiation

MR angiography

Advantages

• Can detect stenosis and occlusions as well as adjacent nonvascular pathology

• Accurately defines the level of disease

• Avoids radiation exposure

Disadvantages

• Poor bolus timing may result in venous contamination artifact

• May overestimate the degree of stenosis

• Expensive

• Time consuming

• Requires significant patient cooperation to minimize motion artifact

Angiography

Advantages

• Traditional gold-standard exam

• Pressure measurements can help determine if a lesion is hemodynamically significant

• Treatment may be performed at the same time as diagnosis

Disadvantages

• Invasive procedure with potential for access site and catheter-based complications

• Not as accurate as CT or MRI in defining the degree of luminal cross-sectional narrowing

• Requires intravenous contrast, which may result in contrast-induced nephropathy

VI. What are the contraindications for the alternative imaging techniques?

Doppler US

• No significant contraindications exist

CT angiography

• Renal failure owing to the risk of contrast-induced nephropathy

• Pregnancy

• Contrast allergy may be a relative contraindication

MR angiography

• Non–MR-compatible hardware

• Renal failure due to the risk of nephrogenic systemic fibrosis

• First trimester pregnancy may be a relative contraindication

Angiography

• Renal failure due to the risk of contrast-induced nephropathy

• Pregnancy

• Contrast allergy may be a relative contraindication