CCI Peripheral Arterial Evaluation 5 — Questions and Answers
Question 1: A duplex scan reveals a focal aneurysm of the popliteal artery measuring 2.5 cm. Which complication is most commonly associated with popliteal artery aneurysms?
- Spontaneous rupture
- Thromboembolism causing acute limb ischemia (Correct answer)
- Arteriovenous fistula formation
- Vessel wall dissection
Correct answer: Thromboembolism causing acute limb ischemia
Popliteal artery aneurysms most commonly cause limb-threatening thromboembolism rather than rupture.
Question 2: When performing an arterial duplex of the lower extremity, which transducer frequency is most appropriate for imaging the deep femoral (profunda femoris) artery in an obese patient?
- 12–15 MHz
- 7.5–10 MHz
- 3–5 MHz (Correct answer)
- 1–2 MHz
Correct answer: 3–5 MHz
A lower frequency of 3–5 MHz provides greater tissue penetration needed to image deep vessels in obese patients despite reduced resolution.
Question 3: A patient has a normal ABI at rest but develops claudication after walking. Which test is most appropriate to evaluate for hemodynamically significant PAD?
- Venous duplex scan
- Treadmill exercise ABI testing (Correct answer)
- Computed tomography without contrast
- Capillary refill time assessment
Correct answer: Treadmill exercise ABI testing
Treadmill exercise ABI testing reveals pressure gradients across stenoses that are compensated and undetectable at rest.
Question 4: On a lower extremity arterial duplex scan, spectral broadening within the waveform most likely indicates:
- Normal laminar flow
- Turbulent flow associated with stenosis (Correct answer)
- Venous reflux
- Arterial vasospasm
Correct answer: Turbulent flow associated with stenosis
Spectral broadening occurs when multiple velocities are present simultaneously, which is characteristic of turbulent flow at or downstream from a stenosis.
Question 5: A patient post-femoral-popliteal bypass graft surveillance duplex shows a PSV of 45 cm/s throughout the graft with a monophasic low-velocity waveform. What does this suggest?
- Normal graft with low resting cardiac output
- Graft at high risk for thrombosis due to low flow state (Correct answer)
- Graft hyperemia from recent surgery
- Inflow vessel stenosis with compensated graft flow
Correct answer: Graft at high risk for thrombosis due to low flow state
A graft PSV below 45–50 cm/s with a low-flow monophasic pattern indicates a failing graft at high risk for thrombosis.
Question 6: Which condition can produce falsely elevated ankle-brachial index values, potentially masking severe PAD?
- Severe anemia
- Medial arterial calcinosis (Mönckeberg's sclerosis) (Correct answer)
- Chronic venous insufficiency
- Peripheral neuropathy
Correct answer: Medial arterial calcinosis (Mönckeberg's sclerosis)
Medial arterial calcinosis renders vessel walls non-compressible, producing artificially high or non-compressible ABI readings despite severe disease.
Question 7: During evaluation of a femoral artery pseudoaneurysm post-catheterization, duplex imaging reveals a to-and-fro flow pattern in the neck connecting the pseudoaneurysm sac to the native artery. What does this pattern represent?
- Normal post-procedure arterial flow
- Bidirectional flow characteristic of a pseudoaneurysm neck (Correct answer)
- Arteriovenous fistula communication
- Turbulence from vessel stenosis
Correct answer: Bidirectional flow characteristic of a pseudoaneurysm neck
The classic to-and-fro pattern in the pseudoaneurysm neck reflects inflow during systole and outflow during diastole between the sac and native artery.
CCI Peripheral Arterial Evaluation 5
A duplex scan reveals a focal aneurysm of the popliteal artery measuring 2.5 cm.
Which complication is most commonly associated with popliteal artery aneurysms?