Patent ID: 8099161

Claim:
A method for determining vessel compliance, the method comprising the steps of: introducing a device into a site within a vessel, the device comprising: a pair of excitation electrodes positioned along a portion of the device; and a pair of detection electrodes positioned along a portion of the device, the pair of detection electrodes comprising two detection electrodes having a known distance from one another, the pair of detection electrodes physically positioned in between the pair of excitation electrodes; operating the device in connection with two or more fluid injections in the vessel at or near the site to obtain two or more conductance values, each of the two or more fluid injections having a known conductivity; calculating a first vessel parameter of the site based on at least two of the two or more conductance values and the conductivities of at least two of the two or more fluid injections; calculating a second vessel parameter of the site based on at least two of the two or more conductance values and the conductivities of at least two of the two or more fluid injections; calculating a change in vessel parameter based upon the first vessel parameter and the second vessel parameter; calculating vessel compliance based upon the relationship between the change in vessel parameter and a change in pressure during a cardiac cycle; and calculating an index of compliance based in part upon a difference between the first vessel parameter and the second vessel parameter divided by the first vessel parameter.