Normal Femoral Artery Peak Systolic Velocity on Ultrasound
The femoral artery is the principal conduit supplying the lower extremity, comprising the common femoral artery (CFA) and its continuation as the superficial femoral artery (SFA). Peak systolic velocity (PSV) is a key duplex ultrasound parameter used to quantify blood flow and detect hemodynamically significant stenosis or occlusion. Accurate PSV measurement is foundational in the noninvasive workup of peripheral arterial disease (PAD).
Normal Reference Values
| Location | Measurement |
|---|---|
| Common | 89-141 cm/s |
| Superficial | 77-108 cm/s |
Clinical Significance
Normal PSV in the common femoral artery ranges from 89–141 cm/s and in the superficial femoral artery from 77–108 cm/s. A focal PSV elevation exceeding these baseline values — particularly a PSV ratio ≥2.0 compared with an adjacent normal segment — indicates a hemodynamically significant stenosis of ≥50%. Markedly elevated focal velocities (often >200–300 cm/s) correspond to severe stenoses, while absent or markedly reduced velocities suggest near-occlusion or occlusion.
Diffusely reduced PSV throughout the femoral segments may reflect proximal inflow disease (e.g., aortoiliac stenosis) rather than intrinsic femoral pathology, a common interpretive pitfall. Waveform morphology — triphasic, biphasic, or monophasic — provides additional physiologic context beyond PSV alone.
- Atherosclerotic stenosis — focal PSV elevation with post-stenotic turbulence
- Femoral artery occlusion — absent flow, collateral recruitment
- Aortoiliac inflow disease — diffusely dampened, monophasic waveforms
- Pseudoaneurysm — to-and-fro “yin-yang” flow pattern at anastomotic or puncture sites
- Arteriovenous fistula — markedly elevated PSV with low-resistance waveform
Reference: Shionoya S. Noninvasive diagnostic techniques in vascular disease. Int Angiol. 6 (3): 213-21.
Imaging Notes
PSV is obtained with duplex (B-mode + pulsed-wave Doppler) ultrasound. Place the sample gate within the vessel lumen, keeping the Doppler angle at 60° or less to the vessel wall — angles exceeding 60° introduce significant velocity overestimation. The sample volume should be positioned at the point of maximum flow, typically the center of the lumen. Optimize the angle correction cursor parallel to the vessel wall rather than the direction of flow for greatest reproducibility.
For the common femoral artery, image just distal to the inguinal ligament; for the superficial femoral artery, trace the vessel through the adductor canal, adjusting probe position to maintain adequate insonation angle throughout. Wall calcification may cause acoustic shadowing, limiting angle correction accuracy, and should be documented as a technical limitation.