Characterization of a carotid distension waveform from audio signal acquired with a stethoscope

Abstract

Non-invasive methodologies for diagnostic and prevention of cardiovascular problems has a special interest in the measurement of blood pressure because of its implications in arterial stiffness, mostly as a consequence of arteriosclerosis. Assuming an established relationship in the literature between blood pressure and the carotid artery flow measured with Doppler ultrasound, in this work a carotid distension waveform has been extracted from carotid audio signal obtained with a conventional stethoscope. For evaluation of the proposed approach fiducial points from the obtained carotid audio signal has been compared with fiducial point in the Doppler blood flow velocity waveform. Preliminary results show a good correspondence between the processed audio signals and Doppler spectrum.