RVT - Registered Vascular Technologist Post-Intervention and Grafts Questions and Answers

Question 1

A patient undergoes duplex surveillance one year after an endovascular aortic aneurysm repair (EVAR).
The aneurysm sac has increased in diameter by 7 mm since the last study, but no endoleak can be visualized with color or spectral Doppler.
This condition is best described as:

Accepted Answer

Endotension

Answer

Graft limb thrombosis

Answer

A Type II endoleak

Answer

A Type III endoleak

Question 2

During surveillance of a prosthetic femoropopliteal bypass graft, a focal area of color aliasing is noted mid-graft. The peak systolic velocity (PSV) within this segment is 320 cm/s. The PSV in a normal-appearing graft segment just proximal to this area is 150 cm/s. What is the velocity ratio (Vr), and what is the most likely interpretation?

Accepted Answer

Vr = 2.1; Significant (≥50%) stenosis

Answer

Vr = 1.7; Mild (<50%) stenosis

Answer

Vr = 0.47; Suggests proximal disease

Answer

Vr = 2.5; Suggests impending occlusion

Question 3

Which of the following sonographic findings is a key component of the 'Rule of 6s' for assessing the maturation of a newly created arteriovenous fistula (AVF) for hemodialysis access?

Accepted Answer

Volume flow should be greater than 600 mL/min

Answer

Fistula depth from the skin surface must be greater than 6 mm

Answer

Minimum fistula diameter must be at least 6 cm

Answer

The fistula should be at least 6 cm from the antecubital fossa

Question 4

A patient is being evaluated one year after undergoing carotid artery stenting (CAS). Duplex ultrasound of the stented segment reveals a peak systolic velocity (PSV) of 350 cm/s and an end-diastolic velocity (EDV) of 145 cm/s. These findings are most consistent with:

Accepted Answer

Severe (≥70-80%) in-stent restenosis.

Answer

Normal, expected velocities within a carotid stent.

Answer

Mild (<50%) in-stent restenosis.

Answer

Stent occlusion with collateral flow.

Question 5

What is the expected spectral Doppler waveform morphology in a normally functioning, mature lower extremity reversed saphenous vein bypass graft that is supplying the ankle and foot?

Accepted Answer

High-resistance, multiphasic (triphasic or biphasic)

Answer

Low-resistance, monophasic with high diastolic flow

Answer

A 'tardus parvus' waveform

Answer

A continuous, non-pulsatile venous-like signal

Question 6

During an EVAR follow-up ultrasound, flow is detected originating from patent lumbar arteries that perfuses the aneurysm sac in a retrograde fashion. This finding is the classic presentation of which type of endoleak?

Accepted Answer

Type II

Answer

Type I

Answer

Type III

Answer

Type IV