# US 10,368,776 B2 · Method and apparatus for determining cardiac performance in a patient with a conductance catheter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,368,776 B2 - Document ID: US10368776B2 - Status: Granted - Kind: B2 - Application number: 15/816,048 - Filed: 2017-11-17 - Published: 2018-03-15 - Granted: 2019-08-06 - Earliest claimed: 2003-09-09 - Assignees: Board of Regents, The University of Texas System - Applicants: Marc D. Feldman; Jonathan W. Valvano; John A. Pearce; Chia-Ling Wei - Inventors: Marc D. Feldman; Jonathan W. Valvano; John A. Pearce; Chia-Ling Wei - Web page: https://patentgrep.com/patent/US10368776B2 ## CPC - A61B 5/0538: invasively, e.g. using a catheter - A61B 5/02007: {Evaluating blood vessel condition, e.g. elasticity, compliance} - A61B 5/0215: by means inserted into the body - A61B 5/029: Measuring blood output from the heart, e.g. minute volume - A61B 5/053: Measuring electrical impedance or conductance of a portion of the body - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract An apparatus for determining cardiac performance in the patient includes a plurality of electrodes adapted to be placed in the patient and in communication with a heart chamber of the patient for measuring conductance and blood volume in the heart chamber of the patient; and a processor for determining instantaneous volume of the ventricle based on measurement of complex admittance at a plurality of frequencies to identify mechanical strength of the chamber, the processor in communication with the electrodes. A method for determining cardiac performance in a patient. ## Claims ### Claim 1 An apparatus for determining cardiac performance in a patient comprising: a plurality of electrodes adapted to he placed in the patient and in communication with a heart chamber of the patient for measuring conductance and blood volume in the heart chamber of the patient and acquiring a measurement of admittance; and a processor for determining instantaneous blood volume of the ventricle based on measurement of admittance to identify mechanical strength of the chamber, the processor in communication with the electrodes. ### Claim 2 (depends on 1) An apparatus as described in claim 1 wherein the processor produces a plurality of desired wave forms at desired frequencies for the electrodes. ### Claim 3 (depends on 2) An apparatus as described in claim 2 wherein the processor produces the plurality of desired wave forms at desired frequencies simultaneously, and the processor separates the plurality of desired wave forms at desired frequencies the processor receives from the electrodes. ### Claim 4 (depends on 3) An apparatus as described in claim 3 wherein the plurality of electrodes is disposed on a conductance catheter to measure a least one segmental volume of the heart chamber. ### Claim 5 (depends on 4) An apparatus as described in claim 4 wherein the pressure sensor is in contact with the conductance catheter to measure ventricular pressure in the chamber. ### Claim 6 (depends on 5) An apparatus as described in claim 5 including a pressure sensor for measuring instantaneous pressure of the heart chamber in communication with the processor. ### Claim 7 (depends on 6) An apparatus as described in claim 6 wherein the plurality of electrodes includes intermediate electrodes to measure and instantaneous voltage signal from the heart, and outer electrodes to which a current is applied from the processor. ### Claim 8 (depends on 7) An apparatus as described in claim 7 wherein the pressure sensor is disposed between the intermediate electrodes and the outer electrodes. ### Claim 9 (depends on 8) An apparatus as described in claim 8 wherein the processor includes a computer with a signal synthesizer which produces the plurality of desired wave forms at desired frequencies and a data acquisition mechanism for receiving and separating the plurality of desired wave forms at desired frequencies. ### Claim 10 A method for determining cardiac performance in a patient comprising the steps of: measuring conductance and blood volume in a heart chamber of the patient and acquiring a measurement of admittance with a plurality of electrodes disposed in the patient and in communication with the heart chamber; and determining instantaneous volume of the ventricle based on measurement of admittance to identify mechanical strength of the chamber with a processor, the processor in communication with the electrodes. ### Claim 11 (depends on 10) A method as described in claim 10 including the step of producing a plurality of desired wave forms at desired frequencies for the electrodes disposed on a conductance catheter. ### Claim 12 (depends on 11) A method as described in claim 11 wherein the producing step includes the step of producing the plurality of desired wave forms at desired frequencies simultaneously, and including the step of the processor separating the plurality of desired wave forms at desired frequencies the processor received from the conductance catheter. ### Claim 13 (depends on 12) A method as described in claim 12 wherein the producing step includes the step of producing with the processor the plurality of desired wave forms at desired frequencies simultaneously. ### Claim 14 An apparatus for determining cardiac performance in a patient comprising: a plurality of electrodes adapted to be placed in the patient and in communication with a heart chamber of the patient for measuring blood volume in the heart chamber of the patient and acquiring a measurement of admittance; and a processor for determining instantaneous blood volume of the ventricle based on measurement of admittance magnitude to identify mechanical strength of the chamber, the processor in communication with the electrodes.