Stent effects on duplex velocity estimates

Sonographic grading of recurrent stenosis after carotid stenting and stented peripheral arteries

“…Furthermore, stent design, which was not taken into account in many studies, seems to have an impact on the rigidity and thus the rise in PSV following stent placement. For example, closed-cell stents show a significantly higher PSV compared with open-cell stents (mean PSV 115 cm/s versus 93 cm/s, p = 0.003) [22]. This was confirmed in another study [39] (mean PSV 122 cm/s versus 93 cm/s, p = 0.007).…”

“…A mismatch between stented and native segments of the artery is also hypothetically postulated [20]. Another study described significantly reduced compliance (ratio of systolic/diastolic diameter changes and systolic/diastolic blood pressure changes) in stented arteries [21]; however, other in vitro experiments failed to detect any relevant, or at most only a slight, increase in flow velocity in stented areas in flow models between unstented and stented vessel areas [22,23]. Thus, in this experiment, the mean PSV increased by only 6.4% in a stented compared to a nonstented model [22], and in a comparison of different stents, a stent-dependent difference in PSV, partly an increase and partly also a drop in PSV, was observed [23]; however, closed-cell stents in particular exhibit a higher PSV compared to open-cell stents [24].…”

In vitro high-frame-rate contrast-enhanced ultrasound particle image velocimetry in a carotid artery stent

“…Imaging blood flow characteristics in the presence of a stent is challenging using MRI or CT, due to metal artefacts. Using ultrasound Doppler, flow velocities can be examined reliably, even in the presence of a stent [4]. However, it is difficult to visualize complex flow patterns in detail using a clinical ultrasound device, since ultrasound Doppler only measures mean velocity magnitudes.…”