Intravascular sensing method and system

A method of calculating a corrected Fractional Flow Reserve comprising:

• delivering a pressure sensing device to a location in an artery, the location having a stenosis;
• positioning the pressure sensing device distal to the stenosis;
• measuring a pressure distal to the stenosis while the pressure sensing device is positioned distal to the stenosis;
• measuring a pressure proximal to the stenosis;
• selecting a correction factor or correction equation, wherein the selection of the correction factor or correction equation is determined by the maximum cross-sectional area of a portion of the pressure sensing device crossing the stenosis during the step of measuring the distal pressure;
• and
• calculating a corrected Fractional Flow Reserve using the measured proximal and distal pressures and applying the correction factor or correction equation;
• wherein the corrected Fractional Flow Reserve approximates a Fractional Flow Reserve that would have been obtained if the distal pressure was measured using a different device having a different maximum cross-sectional area in a portion of the different device crossing the stenosis while measuring the distal pressure or if no device was present crossing the stenosis while measuring the distal pressure.

A system for calculating a corrected Fractional Flow Reserve associated with a stenosis in an artery comprising:

• a pressure sensing device configured for placement within an artery to measure pressure distal to a lesion;
• a processing device in communication with the pressure sensing device;
• and
• a data set comprising a group of at least two correction factors or correction equations, each correction factor or correction equation corresponding to a maximum cross-sectional area of a portion of a standard pressure sensing device that crosses a stenosis when measuring a pressure distal to the stenosis or to an identity of a standard pressure sensing device, wherein the data set is stored within a memory component of the processing device or within a memory component accessible by the processing device;
• wherein the processing device is configured to select a correction factor or correction equation based upon a maximum cross-sectional area of a portion of the pressure sensing device of the system which crosses a stenosis when measuring a pressure distal to the stenosis or based on an identity of the pressure sensing device of the system;
• wherein the processing device is further configured to calculate a corrected Fractional Flow Reserve using the selected correction factor or correction equation and pressure data received from the pressure sensing device.