Devices for determining flow reserve within a luminal organ

Abstract

Devices, systems, and methods to determine fractional flow reserve. At least one method for determining fractional flow reserve of the present disclosure comprises the steps positioning a device comprising at least two sensors within a luminal organ at or near a stenosis, wherein the at least two sensors are separated a predetermined distance from one another, operating the device to determine flow velocity of a second fluid introduced into me luminal organ to temporarily displace a first fluid present within the luminal organ, and determining fractional flow reserve at or near the stenosis based upon the flow velocity, a mean aortic pressure within the luminal organ, and at least one cross-sectional area at or near the stenosis. Devices and systems useful for performing such exemplary methods are also disclosed herein.

1 . A device for determining a flow reserve of a fluid within a luminal organ, the device comprising:
 an elongated body sized and shaped to fit within a luminal organ; and   at least two sensors separated a predetermined distance from one another;   wherein the device operable to determine a flow velocity of a fluid within a mammalian luminal organ and to obtain conductance data within the mammalian luminal organ useful to determine a cross-sectional area of the mammalian luminal organ, when at least part of the device is positioned within the mammalian luminal organ; and   wherein the device is configured to operably couple to a data acquisition and processing system configured to (a) determine the cross-sectional area using the conductance data, (b) determine a pressure measurement within the mammalian luminal organ using the flow velocity and the cross-sectional area, without the use of a pressure sensor, and (c) determine a flow reserve at or near a stenosis within the mammalian luminal organ using the cross-sectional area, the flow velocity, and the pressure measurement.   
     
     
         2 . The device of  claim 1 , wherein the device is operable to determine the flow reserve based upon the flow velocity, the pressure measurement, and the cross-sectional area comprising a cross-sectional area of the luminal organ distal to the stenosis and a cross-sectional area of the luminal organ proximal to the stenosis. 
     
     
         3 . The device of  claim 1 , wherein the device is operable to determine the flow reserve based upon the flow velocity, the pressure measurement, and the cross-sectional area comprising a cross-sectional area of the luminal organ distal to the stenosis, a cross-sectional area of the luminal organ proximal to the stenosis, and a cross-sectional area of the luminal organ at the stenosis. 
     
     
         4 . The device of  claim 1 , forming part of an impedance system, the impedance system further comprising the data acquisition and processing system. 
     
     
         5 . A device for determining a flow reserve of a fluid within a luminal organ, the device comprising:
 an elongated body sized and shaped to fit within a luminal organ; and   at least two sensors positioned along the elongated body a predetermined distance from one another;   wherein the device is operable to detect a first fluid with a first parameter having a first value using at least one of the at least two sensors when the device is positioned within the luminal organ;   wherein the device is further operable to detect a second fluid having a second parameter, wherein the second parameter of the second fluid has a second value different from the first value, upon introduction of the second fluid within the luminal organ at or near the at least two sensors; and   wherein the device is further operable to determine a flow reserve of a fluid within the luminal organ when the device is positioned within the luminal organ at or near a stenosis, wherein the flow reserve is based upon a flow velocity obtained by the device, a mean aortic pressure within the luminal organ, and at least one cross-sectional area at or near the stenosis.   
     
     
         6 . The device of  claim 5 , wherein the second fluid detected by the at least two sensors allows for the determination of the flow velocity based upon timing of the detected second fluid by the at least two sensors and the distance between the at least two sensors. 
     
     
         7 . The device of  claim 5 , wherein the device is operable to determine the flow reserve based upon the flow velocity obtained by the device, the mean aortic pressure within the luminal organ, a cross-sectional area of the luminal organ distal to the stenosis, and a cross-sectional area of the luminal organ proximal to the stenosis. 
     
     
         8 . The device of  claim 5 , wherein the device is operable to determine the flow reserve based upon the flow velocity obtained by the device, the mean aortic pressure within the luminal organ, a cross-sectional area of the luminal organ distal to the stenosis, a cross-sectional area of the luminal organ proximal to the stenosis, and at least one cross-sectional area of the luminal organ at the stenosis. 
     
     
         9 . The device of  claim 5 , wherein the flow velocity allows for the determination of volumetric flow based upon the flow velocity and the at least one cross-sectional area. 
     
     
         10 . The device of  claim 5 , wherein the flow reserve is further based upon a blood viscosity. 
     
     
         11 . The device of  claim 5 , wherein the determination of the flow reserve is made using a data acquisition and processing system operably coupled to the device. 
     
     
         12 . The device of  claim 5 , forming part of an impedance system, the impedance system further comprising the data acquisition and processing system. 
     
     
         13 . A device for determining a flow reserve of a fluid within a luminal organ, the device comprising:
 an elongated body sized and shaped to fit within a luminal organ;   at least one pair of excitation electrodes positioned along the elongated body; and   at least two pairs of detection electrodes positioned along the elongated body between the at least one pair of excitation electrodes, the at least two pairs of detection electrodes positioned a predetermined distance from each other;   wherein when the device is positioned within the luminal organ, the device is operable to detect a first conductance of a first fluid having a first conductivity within the luminal organ using the at least two pairs of detection electrodes, the device further operable to detect a second conductance of a second fluid having a second conductivity using the at least two pairs of detection electrodes upon introduction of the second fluid within the luminal organ at or near the at least two pairs of detection electrodes; and   wherein the device is further operable to determine a flow reserve of a fluid within the luminal organ when the device is positioned within the luminal organ at or near a stenosis, wherein the flow reserve is based upon the a flow velocity obtained by the device, a mean aortic pressure within the luminal organ, and at least one cross-sectional area at or near the stenosis.   
     
     
         14 . The device of  claim 13 , wherein the second fluid detected by using the at least two pairs of detection electrodes allows for the determination of flow velocity based upon timing of the detected second fluid by using the at least two pairs of detection electrodes and the distance between the at least two pairs of detection electrodes. 
     
     
         15 . The device of  claim 13 , wherein the device is operable to determine the flow reserve based upon the flow velocity obtained by the device, the mean aortic pressure within the luminal organ, a cross-sectional area of the luminal organ distal to the stenosis, and a cross-sectional area of the luminal organ proximal to the stenosis. 
     
     
         16 . The device of  claim 13 , wherein the device is operable to determine the flow reserve based upon the flow velocity obtained by the device, the mean aortic pressure within the luminal organ, a cross-sectional area of the luminal organ distal to the stenosis, a cross-sectional area of the luminal organ proximal to the stenosis, and at least one cross-sectional area of the luminal organ at the stenosis. 
     
     
         17 . The device of  claim 13 , wherein the flow velocity allows for the determination of volumetric flow based upon the flow velocity and the at least one cross-sectional area. 
     
     
         18 . The device of  claim 13 , wherein the determination of the flow reserve is made using a data acquisition and processing system operably coupled to the device. 
     
     
         19 . The device of  claim 13 , forming part of an impedance system, the impedance system further comprising the data acquisition and processing system.