Semi-automatic Vendor-Independent Software for Assessment of Local Arterial Stiffness

Background: Stiffened arteries represent a major cardiovascular risk. Aim: We describe a vendor independent software for the non-invasive determination of arterial stiffness using ultrasound images. Methods: We have developed an intensity-based semiautomatic software for determining the edges of the luminal arterial walls (M-mode) and blood velocity (PW Doppler) to extract diameter and velocity waveform from ultrasound images. The upstroke of the two waveforms is automatically determined as well as the fit of the initial linear portion of the ln(D)U-loop. Pulse wave velocity (PWV), which is proportional to the slope of ln(D)U-loop during early systole is calculated as a measure of arterial stiffness. The user can over-ride and correct the automatically determined parameters if necessary. Results: A semi-automatic code was developed for tracing the luminal diameter and blood velocity in the human ascending aorta. D and U waveforms were extracted and used in ln(D)U-loops to calculate PWV. Conclusions: The software described here can be used to assess, local aortic stiffness non-invasively, by using ultrasound measurements/images of the diameter and velocity waveforms.