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This paper reports initial results from our study on the use of non-invasive proximal and distal arterial waveforms to estimate cardiovascular risk predictors while minimizing patient discomfort. We used a pressure wave decomposition technique on carotid tonometry and ankle cuff oscillation waveforms so as to estimate pulse transit time, reflection magnitude and reflection index. We showed that the risk predictors estimated from these waveforms correlated reasonably well with those measured from carotid-femoral tonometry. The results illustrate that ankle cuff oscillation waveform may serve as a viable alternative to femoral tonometry, which requires probe contact near a patient's private area and accompanies inconvenience and discomfort.

This study investigates the validity of two non-invasive arterial pulse waveforms as viable indirect surrogates of arterial blood pressure waveforms, by conducting a data-driven modeling analysis of arterial wave propagation. Using the so-called “tube-load” model, we examined how well the relation between carotid versus femoral tonometry waveforms as well as carotid tonometry versus ankle pulse volume recording waveforms can be fitted to the model. Since the tube-load model describes the relationship between proximal versus distal blood pressures, we hypothesized that viable surrogates of blood pressure waveforms must be fitted well by the tube-load model. Preliminary results derived from 4 subjects with cardiovascular diseases indicated that carotid and femoral tonometry waveforms may serve as viable surrogate of arterial BP waveforms while PVR may need additional treatment, which was attributed to the nature of PVR waveforms: they are volume waveforms but not pressure waveforms.