SYSTEM FOR PERFORMING REAL-TIME AORTIC VALVE DIAMETER MEASUREMENT

Abstract

A method and apparatus for measuring the inflation diameter, cross-sectional area, and/or volume of an inflatable balloon on a balloon catheter.

Claims

1. A method for measuring a) a diameter of at least a portion or all of a medical device that is expanded in a body passageway, b) a cross-sectional area of at least a portion or all of said medical device that is expanded in said body passageway, and/or c) a volume of at least a portion or all of said medical device that is expanded in said body passageway comprising: providing said medical device; said medical device includes a balloon catheter; said balloon catheter includes a catheter body having a distal portion, a central portion, and proximal portion; said balloon catheter includes an inflatable balloon connected at or near said distal portion; providing a diameter measurement device (DMD) is configured to measure a) said diameter of at least a portion or all of said medical device that is expanded in said body passageway, b) said cross-sectional area of at least a portion or all of said medical device that is expanded in said body passageway, and/or c) said volume of at least a portion or all of said medical device that is expanded in said body passageway; said DMD includes a plurality of excitation electrodes and a plurality of sensor electrodes; said plurality of excitation electrodes and said plurality of sensor electrodes are positioned inside said inflatable balloon; said plurality of excitation electrodes and said plurality of sensor electrodes are spaced from one another; inserting said distal portion and a portion of said central portion of said catheter into said body passageway; moving said distal portion of said catheter in said body passageway until said distal portion is positioned at a treatment area; expanding said inflatable balloon at said treatment area; and measuring a change in impedance by said DMD to determine at said treatment area a) said diameter of at least a portion or all of said medical device that is expanded in said body passageway, b) said cross-sectional area of at least a portion or all of said medical device that is expanded in said body passageway, and/or c) said volume of at least a portion or all of said medical device that is expanded in said body passageway, and wherein said change in impedance is at least partially related to said cross-sectional area and/or a pressure of said inflatable balloon.

2. The method as defined in claim 1, wherein said measuring a) said diameter of at least a portion or all of said medical device that is expanded in said body passageway, b) said cross-sectional area of at least a portion or all of said medical device that is expanded in said body passageway, and/or c) said volume of at least a portion or all of said medical device that is expanded in said body passageway is in real time or near real time.

3. The method as defined in claim 1, wherein said medical device includes a stent or prosthetic heart valve that is at least partially positioned about said inflatable balloon.

4. The method as defined in claim 1, wherein said distal portion of said catheter includes a temperature sensor.

5. The method as defined in claim 1, wherein said DMD includes multiplexed inputs.

6. The method as defined in claim 1, wherein said DMD includes a wireless transmitter that wirelessly transmits data to a remote location so that data can be stored and/or displayed at said remote location.

7. The method as defined in claim 1, wherein said DMD includes a reference container; said reference container has a) fixed and constant cross-sectional area along a longitudinal length of said reference container, b) a fixed and constant volume, c) a fixed and constant cross-sectional area along a longitudinal length of said reference container, and/or d) a fixed and constant cross-sectional shape along a longitudinal length of said reference container; said reference container includes a plurality of reference electrodes located in said reference container; a number, orientation, and/or spacing of said plurality of reference electrodes in said reference container is the same or substantially the same as a number, orientation, and/or spacing of said excitation and senor electrodes in said inflatable balloon.

8. The method as defined in claim 7, wherein said reference container has the same or similar a) longitudinal length, b) volume, c) cross-sectional area along a longitudinal length of said reference container, and/or d) cross-sectional shape along said longitudinal length of said reference container as said inflatable balloon when said inflatable balloon is partially or fully inflated.

9. The method as defined in claim 7, wherein said reference container is used to calculate a medium conductivity of a medium; said medium is used to inflate said inflatable balloon.

10. The method as defined in claim 9, wherein said medium includes a saline solution.

11. The method as defined in claim 1, wherein said step of measuring a change in said impedance includes impedance planimetry, wherein a constant voltage source having a high precision waveform is used across a known calibration resistor and impedance measurements are optionally sequenced across electrodes for segmental impedance measurements using the calibrated current value and voltages determined from each segment.

12. The method as defined in claim 1, further includes a flow sensor to provide information about a total volume of fluid into said inflatable balloon, and wherein said flow sensor can be optionally used to monitor a fluid flow rate and/or a total fluid volume delivered to said inflatable balloon to provide additional information for determining said diameter, said cross-sectional area and/or said volume of at least a portion or all of said medical device based on known relationships of said inflatable balloon.

13. The method as defined in claim 1, further includes a pressure sensor located distally in said inflation balloon and/or proximally in an inflating system, and wherein said pressure sensor is optionally used to facilitate determining said diameter, said cross-sectional area and/or said volume of at least a portion or all of said medical device by known pressure volume compliance calculations for said inflatable balloon and/or said inflating system.

14. A diameter measurement device system (DMDS) configured to measure a) a diameter of at least a portion or all of a medical device that is expanded in a body passageway, b) a cross-sectional area of at least a portion or all of said medical device that is expanded in said body passageway, and/or c) a volume of at least a portion or all of said medical device that is expanded in said body passageway; said DMDS comprises: said medical device; said medical device includes a balloon catheter; said balloon catheter includes a catheter body having a distal portion, a central portion, and proximal portion; said balloon catheter includes said inflatable balloon that is connected at or near said distal portion; a plurality of excitation electrodes and a plurality of sensor electrodes; said plurality of excitation electrodes and said plurality of sensor electrodes are positioned inside said inflatable balloon; said plurality of excitation electrodes and said plurality of sensor electrodes are spaced from one another; a plurality of wires that provide current to said plurality of excitation electrodes and said plurality of sensor electrodes; each of said plurality of excitation electrodes and said plurality of sensor electrodes partially or fully encircle said plurality of wires; and wherein said DMDS is configured to measure a change in an impedance derived cross-sectional area and pressure of said inflatable balloon as said inflatable balloon is inflated to determine a) said diameter of at least a portion or all of said medical device that is expanded in said body passageway, b) said cross-sectional area of at least said portion or all of the medical device that is expanded in said body passageway, and/or c) said volume of at least said portion or all of said medical device that is expanded in said body passageway.

15. The diameter measurement device system as defined in claim 14, wherein said medical device includes a stent or prosthetic heart valve that is at least partially positioned about said inflatable balloon.

16. The diameter measurement device system as defined in claim 14, wherein said distal portion of said catheter includes a temperature sensor.

17. The diameter measurement device system as defined in claim 14, wherein said DMDS includes multiplexed inputs.

18. The diameter measurement device system as defined in claim 14, wherein said DMDS includes a wireless transmitter that wirelessly transmits data to a remote location so that data can be stored and/or displayed at said remote location.

19. The diameter measurement device system as defined in claim 14, wherein said DMD includes a reference container; said reference container has a) fixed and constant cross-sectional area along a longitudinal length of said reference container, b) a fixed and constant volume, c) a fixed and constant cross-sectional area along a longitudinal length of said reference container, and/or d) a fixed and constant cross-sectional shape along a longitudinal length of said reference container; said reference container includes a plurality of reference electrodes located in said reference container; a number, orientation, and/or spacing of said plurality of reference electrodes in said reference container is the same or substantially the same as a number, orientation, and/or spacing of said excitation and senor electrodes in said inflatable balloon.

20. The diameter measurement device system as defined in claim 19, wherein said reference container has the same or similar a) longitudinal length, b) volume, c) cross-sectional area along a longitudinal length of said reference container, and/or d) cross-sectional shape along said longitudinal length of said reference container as said inflatable balloon when said inflatable balloon is partially or fully inflated.

21. The diameter measurement device system as defined in claim 19, wherein said reference container is used to calculate a medium conductivity of a medium; said medium is used to inflate said inflatable balloon.

22. The diameter measurement device system as defined in claim 21, wherein said medium includes a saline solution.

23. The diameter measurement device system as defined in claim 14, wherein a constant voltage source having a high precision waveform is used across a known calibration resistor and impedance measurements are optionally sequenced across electrodes for segmental impedance measurements using the calibrated current value and voltages determined from each segment.

24. The diameter measurement device system as defined in claim 14, further including a flow sensor to provide information about total volume of fluid in said inflatable balloon, and wherein said flow sensor can be optionally used to monitor a fluid flow rate and/or a total fluid volume delivered to said inflatable balloon provide additional information for determining said diameter of at least a portion or all of said medical device, said cross-sectional area of at least a portion or all of said medical device and/or said volume of at least a portion or all of said medical device based on known relationships of said inflatable balloon.

25. The diameter measurement device system as defined in claim 14, further including a pressure sensor located distally in said inflation balloon and/or proximally in an inflating system, and wherein said pressure sensor is optionally used to facilitate determining said diameter, said cross-sectional area, and/or said volume of at least a portion or all of said medical device by known pressure volume compliance calculations for said inflatable balloon and/or said inflating system.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0048] The above and other features and advantages of the disclosure will become apparent from a consideration of the subsequent detailed description presented in connection with the accompanying drawings in which:

[0049] FIG. 1 illustrates a block diagram of a catheter that includes a diameter measurement device (DMD) that can be used to measure in real-time a) the diameter of a medical device that is expanded in the cardiovascular system, b) the cross-sectional area of a medical device that is expanded in the cardiovascular system, and/or c) the volume of a medical device that is expanded in the cardiovascular system.

DETAILED DESCRIPTION OF NON-LIMITING EMBODIMENTS

[0050] A more complete understanding of the articles/devices, processes and components disclosed herein can be obtained by reference to the accompanying drawings. These figures are merely schematic representations based on convenience and the ease of demonstrating the present disclosure, and are, therefore, not intended to indicate relative size and dimensions of the devices or components thereof and/or to define or limit the scope of the exemplary embodiments.

[0051] These and other advantages will become apparent to those skilled in the art upon the reading and following of this description.

[0052] Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the embodiments selected for illustration in the drawings and are not intended to define or limit the scope of the disclosure. In the drawings and the following description below, it is to be understood that like numeric designations refer to components of like function.

[0053] The singular forms a, an, and the include plural referents unless the context clearly dictates otherwise.

[0054] As used in the specification and in the claims, the term comprising may include the embodiments consisting of and consisting essentially of. The terms comprise(s), include(s), having, has, can, contain(s), and variants thereof, as used herein, are intended to be open-ended transitional phrases, terms, or words that require the presence of the named ingredients/steps and permit the presence of other ingredients/steps. However, such description should be construed as also describing compositions or processes as consisting of and consisting essentially of the enumerated ingredients/steps, which allows the presence of only the named ingredients/steps, along with any unavoidable impurities that might result therefrom, and excludes other ingredients/steps.

[0055] Numerical values in the specification and claims of this application should be understood to include numerical values which are the same when reduced to the same number of significant figures and numerical values which differ from the stated value by less than the experimental error of conventional measurement technique of the type described in the present application to determine the value.

[0056] All ranges disclosed herein are inclusive of the recited endpoint and independently combinable (for example, the range of from 2 grams to 10 grams is inclusive of the endpoints, 2 grams and 10 grams, and all the intermediate values).

[0057] The terms about and approximately can be used to include any numerical value that can vary without changing the basic function of that value. When used with a range, about and approximately also disclose the range defined by the absolute values of the two endpoints, e.g., about 2 to about 4 also discloses the range from 2 to 4. Generally, the terms about and approximately may refer to plus or minus 10% of the indicated number.

[0058] Percentages of elements should be assumed to be percent by weight of the stated element, unless expressly stated otherwise.

[0059] Some portions of the detailed description herein are presented in terms of algorithms and symbolic representations of operations on data bits performed by conventional computer components, including a central processing unit (CPU), memory storage devices for the CPU, and connected display devices. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is generally perceived as a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.

[0060] It should be understood, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise, as apparent from the discussion herein, it is appreciated that throughout the description, discussions utilizing terms such as processing or computing or calculating or determining or displaying or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.

[0061] The exemplary embodiment also relates to an apparatus for performing the operations discussed herein. This apparatus may be specially constructed for the required purposes, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a computer readable storage medium, such as, but not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.

[0062] The algorithms and displays presented herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform the methods described herein. The structure for a variety of these systems is apparent from the description above. In addition, the exemplary embodiment is not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the exemplary embodiment as described herein.

[0063] A machine-readable medium includes any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For instance, a machine-readable medium includes read only memory (ROM), random access memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, and electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.).

[0064] The methods illustrated throughout the specification, may be implemented in a computer program product that may be executed on a computer. The computer program product may comprise a non-transitory computer-readable recording medium on which a control program is recorded, such as a disk, hard drive, or the like. Common forms of non-transitory computer-readable media include, for example, floppy disks, flexible disks, hard disks, magnetic tape, or any other magnetic storage medium, CD-ROM, DVD, or any other optical medium, a RAM, a PROM, an EPROM, a FLASH-EPROM, or other memory chip or cartridge, or any other tangible medium from which a computer can read and use.

[0065] One non-limiting exemplary embodiment is described herein. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

[0066] Referring now to FIG. 1, there is illustrated a block diagram of a catheter 100 that includes a diameter measurement device (DMD) 200 that can be used to measure in real-time a) the diameter of a medical device that is expanded in the cardiovascular system, b) the cross-sectional area of a medical device that is expanded in the cardiovascular system, and/or c) the volume of a medical device that is expanded in the cardiovascular system. Positioned on the distal portion of catheter 100 is an inflatable balloon 300.

[0067] DMD 200 includes a plurality of wires 210 that conducts current from a power source (not shown). Positioned inside inflatable balloon 300 are a plurality of excitation electrodes 220 and a plurality of sensor electrodes 230. The two sensor electrodes 230 are illustrated as being positioned between excitation electrodes 220; however, this is not required.

[0068] A temperature sensor 400 is optionally positioned at or near the distal tip of catheter 100.

[0069] Positioned at or near the posterior end of catheter 100 is an optional reference tube 500.

[0070] Reference tube 500 can be optionally fluidly connected to the body 110 of the catheter 100. Reference tube 500 is a fixed and constant diameter tube and/or a fixed and constant cross-sectional shape and size along a longitudinal length of the tube (e.g., cylindrical tube, etc.) that includes a circuit 510 that is the same or similar to DMD 200 inside inflatable balloon 300. As such circuit 510 includes two excitation electrodes 520 and two sensor electrodes 530 positioned between the two excitation electrodes.

[0071] Body 110 can includes one or more internal passageways that extend along the longitudinal length of body 110. The one or more internal passageways can include wires 210. The one or more internal passageways include a fluid passageway that allows fluid (e.g., saline, etc.) to flow from the proximal end of the catheter to the distal portion of the catheter to enable the inflatable balloon to be inflated and deflated.

[0072] It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the constructions set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. The invention has been described with reference to preferred and alternate embodiments. Modifications and alterations will become apparent to those skilled in the art upon reading and understanding the detailed discussion of the invention provided herein. This invention is intended to include all such modifications and alterations insofar as they come within the scope of the present invention. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, which, as a matter of language, might be said to fall there between. The invention has been described with reference to the preferred embodiments. These and other modifications of the preferred embodiments as well as other embodiments of the invention will be obvious from the disclosure herein, whereby the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims.

[0073] To aid the Patent Office and any readers of this application and any resulting patent in interpreting the claims appended hereto, applicants do not intend any of the appended claims or claim elements to invoke 35 U.S.C. 112(f) unless the words means for or step for are explicitly used in the particular claim.