Non-invasive estimation of arterial compliance

The evaluation of arterial compliance is very important in cardiovascular screening of "at-risk" patients. Existing techniques for local arterial stiffness estimation put a premium on technology and operator expertise. Regional stiffness, measured in terms of the pulse wave velocity, is prone to errors in both path-length and delay estimation. Here, we present a Virtual Instrument (VI) for automated estimation of both local and regional arterial compliance measures. Local arterial compliance is evaluated by utilizing an ultrasound transducer to measure the distension and lumen diameter of the carotid artery. The regional stiffness is estimated from the pulse wave velocity, measured using two magnetic transducers in a dual-channel arrangement. The automated measurement algorithms are thoroughly analyzed, to identify and minimize possible error sources as well as to optimize the design of both the transducer and the virtual instrument. The results of a few human trials are also presented to illustrate the capability of the VI to measure arterial compliance in-vivo.