RVT Peripheral Arterial Physiologic Testing 2 — Questions and Answers
Question 1: A patient with claudication has an ABI of 0.62 at rest. After treadmill exercise, the ABI drops to 0.31 and takes 8 minutes to recover. What does this pattern indicate?
- Mild arterial disease with good collateral flow
- Moderate-to-severe arterial disease with poor collateral compensation (Correct answer)
- Normal exercise response with physiologic hyperemia
- Venous insufficiency masking arterial disease
Correct answer: Moderate-to-severe arterial disease with poor collateral compensation
A post-exercise ABI drop >20% with prolonged recovery (>3 minutes) indicates hemodynamically significant arterial disease with inadequate collateral circulation.
Question 2: Which waveform characteristic on PVR (pulse volume recording) is MOST consistent with proximal aortoiliac occlusive disease?
- Peaked systolic upstroke with sharp dicrotic notch
- Flat, broad waveform with absent dicrotic notch throughout the limb (Correct answer)
- Normal waveform at thigh with abnormal calf waveform
- Biphasic waveform at the ankle with triphasic at the thigh
Correct answer: Flat, broad waveform with absent dicrotic notch throughout the limb
Aortoiliac disease produces diffusely flattened, broadened PVR waveforms throughout the entire lower extremity due to inflow obstruction affecting all segments.
Question 3: During segmental pressure testing, a 30 mmHg pressure gradient is found between the proximal thigh and above-knee segments. Where is the disease most likely located?
- Aortoiliac segment
- Superficial femoral artery (Correct answer)
- Popliteal artery
- Tibial vessels
Correct answer: Superficial femoral artery
A gradient >20 mmHg between proximal thigh and above-knee cuffs localizes disease to the superficial femoral artery in the mid-thigh region.
Question 4: A diabetic patient has non-compressible tibial arteries with ABIs >1.3. Which alternative test is MOST reliable for assessing arterial perfusion in this patient?
- Segmental limb pressures
- Toe-brachial index (TBI) (Correct answer)
- Venous duplex ultrasound
- CT angiography without contrast
Correct answer: Toe-brachial index (TBI)
The toe arteries are typically spared from medial calcification in diabetics, making the TBI the preferred non-invasive pressure index when ABIs are non-compressible.
Question 5: What is the normal toe-brachial index (TBI) value in a healthy adult?
- >0.60 (Correct answer)
- >0.80
- >1.00
- >0.40
Correct answer: >0.60
A normal TBI is ≥0.70 in most references, with values below 0.60 generally considered abnormal and indicating significant digital arterial disease.
Question 6: Which finding on continuous-wave Doppler examination is MOST indicative of a hemodynamically significant proximal stenosis?
- High-pitched, multiphasic signal with clear window
- Monophasic, low-velocity signal with loss of reverse flow component (Correct answer)
- Biphasic signal with mild spectral broadening
- Triphasic waveform with normal peak systolic velocity
Correct answer: Monophasic, low-velocity signal with loss of reverse flow component
A monophasic, damped signal distal to a significant stenosis results from loss of pulsatility as pressure energy is dissipated across the lesion.
Question 7: A patient undergoing reactive hyperemia testing shows an ABI that falls from 1.0 to 0.55 after 3 minutes of cuff occlusion and takes 5 minutes to return to baseline. What does this indicate?
- Normal arterial response to ischemic stress
- Hemodynamically significant arterial disease (Correct answer)
- Venous obstruction mimicking arterial disease
- Sympathetic nervous system dysfunction
Correct answer: Hemodynamically significant arterial disease
In reactive hyperemia, an ABI drop >15-20% with slow recovery indicates significant arterial occlusive disease unable to meet increased metabolic demand.
RVT Peripheral Arterial Physiologic Testing 2
A patient with claudication has an ABI of 0.62 at rest.
After treadmill exercise, the ABI drops to 0.31 and takes 8 minutes to recover.
What does this pattern indicate?