WO2023073459A1 - Capteur d'hématocrite reposant sur une mesure d'impédance dans des dispositifs électroniques implantables cardiovasculaires - Google Patents

Capteur d'hématocrite reposant sur une mesure d'impédance dans des dispositifs électroniques implantables cardiovasculaires Download PDF

Info

Publication number
WO2023073459A1
WO2023073459A1 PCT/IB2022/059510 IB2022059510W WO2023073459A1 WO 2023073459 A1 WO2023073459 A1 WO 2023073459A1 IB 2022059510 W IB2022059510 W IB 2022059510W WO 2023073459 A1 WO2023073459 A1 WO 2023073459A1
Authority
WO
WIPO (PCT)
Prior art keywords
impedance
indication
processing circuitry
hematocrit
anemia
Prior art date
Application number
PCT/IB2022/059510
Other languages
English (en)
Inventor
Geert Morren
Original Assignee
Medtronic, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US17/955,607 external-priority patent/US20230136130A1/en
Application filed by Medtronic, Inc. filed Critical Medtronic, Inc.
Publication of WO2023073459A1 publication Critical patent/WO2023073459A1/fr

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/18—Applying electric currents by contact electrodes
    • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/36014—External stimulators, e.g. with patch electrodes
    • A61N1/3603—Control systems
    • A61N1/36031—Control systems using physiological parameters for adjustment
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/145—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue
    • A61B5/14535—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue for measuring haematocrit
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/145—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue
    • A61B5/14503—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors

Definitions

  • the disclosure relates to medical devices, and, more particularly, to cardiovascular medical device systems configured to sense hematocrit in a patient.
  • Implantable cardioverter defibrillators (ICDs) and implantable artificial pacemakers may provide cardiac pacing therapy to a patient’s heart when the natural pacemaker and/or conduction system of the heart fails to provide synchronized atrial and ventricular contractions at rates and intervals sufficient to sustain healthy patient function.
  • Such antibradycardial pacing may provide relief from symptoms, or even life support, for a patient.
  • Cardiac pacing may also provide electrical overdrive stimulation, e.g., ATP therapy, to suppress or convert tachyarrhythmias, again supplying relief from symptoms and preventing or terminating arrhythmias that could lead to sudden cardiac death.
  • electrical overdrive stimulation e.g., ATP therapy
  • Cardiac resynchronization therapy is another type of cardiac pacing that may help enhance cardiac output by resynchronizing the electromechanical activity of the ventricles of the heart.
  • Ventricular desynchrony may occur in patients that suffer from heart failure.
  • Treatment of end stage heart failure may include implant of a mechanical circulatory support device (e.g., a ventricular assist device, such as a left ventricular assist device) to aid the heart in pumping blood to the body.
  • a mechanical circulatory support device e.g., a ventricular assist device, such as a left ventricular assist device
  • Hematocrit of blood samples may be determined by sensing the conductance of blood because the conductivity of blood is inversely correlated with the hematocrit.
  • the impedance is measured intracardially (in-vivo), however, there are many confounding factors, such as changes in the sample volume/geometry and motion.
  • FIG. 7A is a conceptual diagram illustrating an example positioning of leads and electrodes used to sense an intrathoracic impedance according to the techniques of this disclosure.
  • FIG. 9 is a flow diagram illustrating example hematocrit sensing techniques of this disclosure.
  • FIG. l is a schematic diagram of an example implantable medical device system 100 in conjunction with a patient 114.
  • a medical device system 100 for sensing cardiac events e.g., P-waves, R-waves, QRS complexes, etc.
  • detecting tachyarrhythmia episodes may include an implantable medical device (IMD) 110, right ventricular lead 118, left ventricular lead 120, and atrial lead 121.
  • IMD implantable medical device
  • Left ventricular lead 120 includes one or more electrodes 130 positioned in the patient’s left ventricle (LV) for sensing ventricular electrogram signals and pacing the LV.
  • Atrial lead 121 includes electrodes 126 and 128 positioned on the lead in the patient's right atrium (RA) for sensing atrial electrogram signals and pacing in the RA.
  • LV left ventricle
  • RA right atrium
  • EGM signal data, hematocrit data, and/or true anemia or fluid overload data acquired by PCD 110 may be transmitted to an external device 21.
  • External device 21 may be embodied as a programmer, e.g., used in a clinic or hospital to communicate with PCD 110 via wireless telemetry.
  • External device 21 may be coupled to a remote patient monitoring system, such as CarelinkTM, available from Medtronic pic, of Dublin, Ireland.
  • External device 21 is used to program commands or operating parameters into PCD 110 for controlling PCD function and to interrogate PCD 110 to retrieve data, including device operational data as well as physiological data accumulated in a memory of PCD 110.
  • Examples of communication techniques used by PCD 110 and external device 21 include low frequency or radiofrequency (RF) telemetry, which may be an RF link established via Bluetooth®, WiFi, medical information communication service (MICS), or another public or proprietary communication protocol.
  • RF radiofrequency
  • external device 21 may receive from PCD 110 an indication of a measurement of hematocrit, an indication of true anemia, or an indication of fluid overload, which a clinician may use to guide treatment of patient 114.
  • the user is a physician, technician, surgeon, electrophysiologist, or other healthcare professional, the user may be patient 14 in some examples.
  • External device 21 may communicate with PCD 110 via wireless communication using any techniques known in the art. Examples of communication techniques are described above with reference to FIG. 1.
  • external device 21 may include a programming head that may be placed proximate to patient 14’s body near the PCD 110 implant site in order to improve the quality or security of communication between PCD 110 and external device 21.
  • a user such as a clinician or patient 114, may interact with external device 21 through user interface 406.
  • User interface 406 may include a display, such as an LCD or LED display or other type of screen, to present information.
  • user interface 406 may be configured to alert a clinician of a measure of hematocrit, an indication of true anemia, or an indication of fluid overload of patient 114, such that the clinician may take the appropriate measures to treat patient 114.
  • user interface 406 may include an input mechanism to receive input from the user.
  • the input mechanisms may include, for example, buttons, a keypad (e.g., an alphanumeric keypad), a peripheral pointing device or another input mechanism that allows the user to navigate through user interfaces presented by processing circuitry 400 of external device 21 and provide input.
  • processing circuitry 400 may determine hematocrit values based on impedance values measured by PCD 110, and/or may determine whether to indicate fluid overload or anemia of patient 114 based on data received from PCD 110.
  • Memory 402 may include instructions for operating user interface 406 and communication circuitry 408, and for managing power source 404. Memory 402 may also store any data retrieved from PCD 110. The clinician may use this therapy data to determine the progression of the patient condition in order to determine future treatment.
  • Memory 402 may include any volatile or nonvolatile memory, such as RAM, ROM, EEPROM or flash memory. Memory 402 may also include a removable memory portion that may be used to provide memory updates or increases in memory capacities. A removable memory may also allow sensitive patient data to be removed before external device 21 is used by a different patient.
  • Wireless telemetry in external device 21 may be accomplished by use of communication circuitry 408, which may communicate with a proprietary protocol or industry-standard protocol such as using the Bluetooth® specification set. Accordingly, communication circuitry 408 may be similar to the communication circuitry contained within by PCD 110. In alternative examples, external device 21 may be capable of infrared communication or direct communication through a wired connection. In this manner, other external devices may be capable of communicating with external device 21 without needing to establish a secure wireless connection.
  • Power source 404 may deliver operating power to the components of external device 21.
  • Power source 404 may include a battery and a power generation circuit to produce the operating power.
  • the battery may be rechargeable to allow extended operation. Recharging may be accomplished by electrically coupling power source 308 to a cradle or plug that is connected to an alternating current (AC) outlet. In addition, recharging may be accomplished through proximal inductive interaction between an external charger and an inductive charging coil within external device 21. In other examples, traditional batteries (e.g., nickel cadmium or lithium ion batteries) may be used.
  • external device 21 may be directly coupled to an alternating current outlet to operate.
  • Power source 404 may include circuitry to monitor power remaining within a battery. In this manner, user interface 406 may provide a current battery level indicator or low battery level indicator when the battery needs to be replaced or recharged. In some cases, power source 404 may be capable of estimating the remaining time of operation using the current battery.
  • FIG. 3 is a functional block diagram illustrating an example configuration of pacemaker/cardioverter/defibrillator (PCD) 110.
  • PCD 110 includes sensing circuitry 422, pulse generation circuitry 420, processing circuitry 416 and associated memory 418, communication circuitry 424, power source 426, and switch circuitry 428.
  • the electronic components may receive power from power source 426, which may be a rechargeable or non-rechargeable battery.
  • PCD 110 may include more or fewer electronic components.
  • the described circuitry may be implemented together on a common hardware component or separately as discrete but interoperable hardware or software components.
  • circuitry Depiction of different features as circuitry is intended to highlight different functional aspects and does not necessarily imply that such circuitry must be realized by separate hardware or software components. Rather, functionality associated with one or more circuitries may be performed by separate hardware or software components or integrated within common or separate hardware or software components.
  • Sensing circuitry 422 receives cardiac electrical signals from electrodes 112, 122, 124, 126, 128, 130, 132, 142 and 144 carried by right ventricular lead 118, left ventricular lead 120, and atrial lead 121, along with housing electrode 112 associated with the housing 112, for sensing cardiac events attendant to the depolarization of myocardial tissue, e.g., P-waves and R-waves, and sensing impedances indicative of hematocrit, true anemia, and/or fluid overload.
  • cardiac events attendant to the depolarization of myocardial tissue e.g., P-waves and R-waves
  • PCD 110 may include switch circuitry 428 for selectively coupling electrodes 122, 124, 126, 128, 130, 132, 142, 144, and housing electrode 112 to sensing circuitry 422.
  • Switch circuitry 428 may include a switch array, switch matrix, multiplexer, or any other type of switching device suitable to selectively couple one or more of the electrodes to sensing circuitry 422.
  • processing circuitry 416 selects the electrodes to function as sense electrodes, or the sensing vector, via switch circuitry 428.
  • PCD 110 may not include switch circuitry 428.
  • processing circuitry 416 may determine a first impedance associated with a heart of patient 114 and determine a second impedance associated with the heart of patient 114. Processing circuitry 416 may determine a measure of hematocrit, an indication of fluid overload, or an indication of true anemia based at least in part on the first impedance and the second impedance. Processing circuitry 416 may output an indication of the measure of hematocrit, the indication of fluid overload, or the indication true anemia, for example, to external device 21 via communication circuitry 242, to inform a clinician.
  • sensing circuitry 422 may be analog components, digital components or a combination thereof.
  • Sensing circuitry 422 may, for example, include one or more sense amplifiers, filters, rectifiers, threshold detectors, analog-to-digital converters (ADCs) or the like.
  • Sensing circuitry 422 may convert the sensed signals to digital form and provide the digital signals to processing circuitry 416 for processing or analysis.
  • sensing circuitry 422 may amplify signals from the sensing electrodes and convert the amplified signals to multi-bit digital signals by an ADC.
  • Sensing circuitry 422 may also compare processed signals to a threshold to detect the existence of atrial or ventricular depolarizations (e.g., P- or R-waves) and indicate the existence of the atrial depolarization (e.g., P-waves) or ventricular depolarizations (e.g., R- waves) to processing circuitry 416. In addition to detecting and identifying specific types of cardiac rhythms, sensing circuitry 422 may also sample the detected intrinsic signals to generate an electrogram or other time-based indication of cardiac events.
  • a threshold to detect the existence of atrial or ventricular depolarizations (e.g., P- or R-waves) and indicate the existence of the atrial depolarization (e.g., P-waves) or ventricular depolarizations (e.g., R- waves) to processing circuitry 416.
  • sensing circuitry 422 may also sample the detected intrinsic signals to generate an electrogram or other time-based indication of cardiac events.
  • Processing circuitry 416 may process the signals from sensing circuitry 422 to monitor electrical activity of the heart of the patient. Processing circuitry 416 may store signals obtained by sensing circuitry 422 as well as any generated electrogram waveforms, marker channel data or other data derived based on the sensed signals in memory 418. Processing circuitry 416 may analyze the electrogram waveforms and/or marker channel data to detect cardiac events (e.g., tachycardia). In response to detecting the cardiac event, processing circuitry 416 may control pulse generation circuitry 420 to deliver the desired therapy to treat the cardiac event, e.g., ATP therapy.
  • cardiac events e.g., tachycardia
  • Memory 418 may include computer-readable instructions that, when executed by processing circuitry 416, cause PCD 110 to perform various functions attributed throughout this disclosure to PCD 110 and processing circuitry 416.
  • the computer- readable instructions may be encoded within memory 418.
  • Memory 418 may comprise computer-readable storage media including any volatile, non-volatile, magnetic, optical, or electrical media, such as a random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically-erasable programmable ROM (EEPROM), flash memory, or any other digital media.
  • RAM random access memory
  • ROM read-only memory
  • NVRAM non-volatile RAM
  • EEPROM electrically-erasable programmable ROM
  • flash memory or any other digital media.
  • Processing circuitry 416 may include any one or more of a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or equivalent discrete or integrated logic circuitry or state machine.
  • processing circuitry 416 may include multiple components, such as any combination of one or more microprocessors, one or more controllers, one or more DSPs, one or more ASICs, or one or more FPGAs, as well as other discrete or integrated logic circuitry or state machines.
  • the functions attributed to processing circuitry 416 herein may be embodied as software, firmware, hardware or any combination thereof.
  • processing circuitry 416 may determine a first impedance associated with a heart of patient 114 and determine a second impedance associated with the heart of patient 114 to determine a hematocrit value of patient 114 according to the techniques of this disclosure.
  • processing circuitry 416 may control pulse generation circuitry 420 to generate measurement or input signals (voltage or current) and sensing circuitry 422 may sense or measure resulting or output signals (current or voltage) via selected combinations of electrodes 122, 124, 126, 128, 130, 132, 142, 144, and housing electrode 112.
  • Communication circuitry 424 is used to communicate with external device 21 for transmitting data accumulated by PCD 110 and for receiving interrogation and programming commands to and/or from external device 21.
  • Communication circuitry 268 includes any suitable hardware, firmware, software or any combination thereof for communicating with another device, such as external device 21 (FIGS. 1 and 2), a clinician programmer, a patient monitoring device, or the like.
  • communication circuitry 424 may include appropriate modulation, demodulation, frequency conversion, filtering, and amplifier components for transmission and reception of data. Under the control of processing circuitry 416, communication circuitry 424 may receive downlink telemetry from and send uplink telemetry to external device 21 with the aid of an antenna, which may be internal and/or external.
  • Processing circuitry 416 may provide the data to be uplinked to external device 21 and the control signals for the telemetry circuit within communication circuitry 424, e.g., via an address/data bus.
  • communication circuitry 424 may provide received data to processing circuitry 416 via a multiplexer.
  • Ep vary as a function of frequency.
  • An alternative embodiment uses information from a second set of impedance measurements in the same tissue but at a different condition (providing different admittance measurements).
  • second set of data can be obtained from measurements at different states of contraction of the heart (e.g., systole vs diastole).
  • Gb may be determined using the following formula: where Y c represents the admittance measured in the alternative condition.
  • Any of the above formulas may provide a quantity which is solely dependent on the conductivity of the blood and is not affected by the surrounding tissue. As the hematocrit is inversely related to the conductivity of the blood, the quantity, as such, can be used to monitor (relative) changes in hematocrit (independent from changes in the surrounding tissue).
  • processing circuitry 416 may determine a first measure of hematocrit based on the blood conductance (e.g., there may be an inverse relationship between hematocrit and blood conductance). In some examples, processing circuitry 416 may receive a second measure of hematocrit from another device (such as a hematocrit sensor), and based on the second measure, determine a calibration factor for processing circuitry 416 to apply to the first measure.
  • part of current may travel to tissue which may make a determined value of impedance inaccurate.
  • tissue may be both resistive and conductive.
  • PCD 110 may take into account the properties of surrounding tissue.
  • treatment for true anemia may depend on pathophysiology, for example, intravenous administration of iron in the case of iron deficiency.
  • Treatment for fluid overload may include, for example, the administration of diuretics to the patient. Therefore, it may be desirable to be able to distinguish or discriminate between true anemia and fluid overload and to output an indication of which condition patient 114 may have in order to guide a clinician in administering the appropriate treatment.
  • processing circuitry 416 may determine an absolute change in intracardiac impedance and an absolute change in intrathoracic impedance and compare the absolute changes to determine an indication of fluid overload or true anemia. In some examples, other measures may be determined as appropriate to determine an indication of fluid overload or true anemia.
  • FIG. 7A is a conceptual diagram illustrating an example positioning of leads and electrodes used to determine an intrathoracic impedance according to the techniques of this disclosure.
  • intrathoracic impedance may be determined by stimulating (e.g., delivering an input signal) from a first electrode (e.g., tip electrode 122) of right ventricular lead 118 to housing electrode 112 of PCD 110 and sensing (e.g., sensing an output signal) between a second electrode (e.g., ring electrode 124) of right ventricular lead 118 and housing electrode 112 of PCD 110.
  • FIG. 7B is a conceptual diagram illustrating an example positioning of leads and electrodes used to determine an intracardiac impedance according to the techniques of this disclosure.
  • intracardiac impedance may be determined by stimulating from a first electrode (e.g., tip electrode 122) of right ventricular lead 118 to a second electrode (e.g., coil electrode 142) of right ventricular lead 118 and sensing between a third electrode (e.g., ring electrode 124) of right ventricular lead 118 and the second electrode of right ventricular lead 118.
  • FIGS. 8 A and 8B are conceptual diagrams illustrating example electrode locations.
  • may be measured at one frequency rather than two frequencies.
  • An initial calibration may be performed, and the admittance may be used to determine a hematocrit level.
  • HCT (
  • Yc is the calibrated admittance
  • HCTc is the calibrated hematocrit level.
  • PCD 110 may determine a first complex impedance based on the first determined impedance, wherein the first determined impedance is determined at a first frequency; and determine a second complex impedance based on the second determined impedance, wherein the second determined impedance is determined at a second frequency. In some examples, determining the measure of hematocrit is based on the first complex impedance and the second complex impedance. In some examples, PCD 110 may determine a phase shift between an input current and an output voltage to calculate a real admittance and an imaginary admittance.
  • PCD 110 may determine blood conductance based on the first complex impedance and the second complex impedance, wherein the determining a measure of hematocrit is further based on the determined blood conductance. In some examples, PCD may calibrate the measure of hematocrit.
  • the relative change in intracardiac impedance is greater than or equal to the relative change in intrathoracic impedance and wherein the indication comprises an indication of true anemia. In some examples, the relative change in intracardiac impedance is less than the relative change in intrathoracic impedance and wherein the indication comprises an indication of fluid overload.
  • any suitable modifications may be made to the techniques described herein and any suitable device, processing circuitry, pulse generation circuitry, and/or electrodes may be used for performing the steps of the methods described herein.
  • the steps of the methods may be performed by any suitable number of devices.
  • a processing circuitry of one device may perform some of the steps while a pulse generation circuitry and/or sensing circuitry of another device may perform other steps of the method, while communication circuitry may allow for communication needed for the processing circuitry to receive information from other devices. This coordination may be performed in any suitable manner according to particular needs.
  • the disclosure contemplates computer-readable storage media comprising instructions to cause a processor to perform any of the functions and techniques described herein.
  • the computer-readable storage media may take the example form of any volatile, non-volatile, magnetic, optical, or electrical media, such as a RAM, ROM, NVRAM, EEPROM, or flash memory.
  • the computer-readable storage media may be referred to as non-transitory.
  • a programmer such as patient programmer or clinician programmer, or other computing device may also contain a more portable removable memory type to enable easy data transfer or offline data analysis.
  • processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components, embodied in programmers, such as physician or patient programmers, stimulators, remote servers, or other devices.
  • processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components, embodied in programmers, such as physician or patient programmers, stimulators, remote servers, or other devices.
  • processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components, embodied in programmers, such as physician or patient programmers, stimulators, remote servers, or other devices.
  • processors including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of
  • Such hardware, software, firmware may be implemented within the same device or within separate devices to support the various operations and functions described in this disclosure.
  • any of the techniques or processes described herein may be performed within one device or at least partially distributed amongst two or more devices, such as between PCD 110 and external device 21.
  • any of the described units, circuitry or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as circuitry is intended to highlight different functional aspects and does not necessarily imply that such circuitry must be realized by separate hardware or software components. Rather, functionality associated with one or more circuitry may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.
  • Example non-transitory computer-readable storage media may include random access memory (RAM), read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), electronically erasable programmable read only memory (EEPROM), flash memory, a hard disk, a compact disc ROM (CD-ROM), a floppy disk, a cassette, magnetic media, optical media, or any other computer readable storage devices or tangible computer readable media.
  • the term “circuitry” refers to an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that execute one or more software or firmware programs, a combinational logic circuit, or other suitable components that provide the described functionality.
  • ASIC application specific integrated circuit
  • a computer-readable storage medium comprises non- transitory medium.
  • the term “non-transitory” may indicate that the storage medium is not embodied in a carrier wave or a propagated signal.
  • a non-transitory storage medium may store data that can, over time, change (e.g., in RAM or cache).

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biophysics (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Physics & Mathematics (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • Veterinary Medicine (AREA)
  • Radiology & Medical Imaging (AREA)
  • Physiology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Optics & Photonics (AREA)
  • Pathology (AREA)
  • Medical Informatics (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Electrotherapy Devices (AREA)

Abstract

Un dispositif donné à titre d'exemple comprend une mémoire configurée pour stocker une première impédance et une seconde impédance associées chacune à un cœur d'un patient, et un circuit de traitement couplé en communication à la mémoire. Le circuit de traitement est configuré pour déterminer au moins l'une d'une mesure d'hématocrite, d'une indication de surcharge de fluide, ou d'une indication d'anémie vraie sur la base au moins en partie de la première impédance et de la seconde impédance. Le circuit de traitement est configuré pour émettre une indication de la mesure d'hématocrite, l'indication d'une surcharge de fluide ou l'indication d'une anémie vraie.
PCT/IB2022/059510 2021-11-01 2022-10-05 Capteur d'hématocrite reposant sur une mesure d'impédance dans des dispositifs électroniques implantables cardiovasculaires WO2023073459A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US202163274295P 2021-11-01 2021-11-01
US63/274,295 2021-11-01
US17/955,607 US20230136130A1 (en) 2021-11-01 2022-09-29 Hematocrit sensor based on impedance measurement in cardiovascular implantable electronic devices
US17/955,607 2022-09-29

Publications (1)

Publication Number Publication Date
WO2023073459A1 true WO2023073459A1 (fr) 2023-05-04

Family

ID=83899647

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2022/059510 WO2023073459A1 (fr) 2021-11-01 2022-10-05 Capteur d'hématocrite reposant sur une mesure d'impédance dans des dispositifs électroniques implantables cardiovasculaires

Country Status (1)

Country Link
WO (1) WO2023073459A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010111349A1 (fr) * 2009-03-24 2010-09-30 Cardiac Pacemakers, Inc. Systèmes de détection, de surveillance et de traitement de l'anémie
US20110098546A1 (en) * 2008-02-08 2011-04-28 Taraneh Ghaffari Farazi Assessing medical conditions based on venous oxygen saturation and hematocrit information
US20130116583A1 (en) * 2011-11-03 2013-05-09 Pacesetter, Inc. Systems and methods for predicting and corroborating pulmonary fluid overloads using an implantable medical device
US20140288551A1 (en) * 2013-03-15 2014-09-25 Pacesetter, Inc. Erythropoeitin production by electrical stimulation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110098546A1 (en) * 2008-02-08 2011-04-28 Taraneh Ghaffari Farazi Assessing medical conditions based on venous oxygen saturation and hematocrit information
WO2010111349A1 (fr) * 2009-03-24 2010-09-30 Cardiac Pacemakers, Inc. Systèmes de détection, de surveillance et de traitement de l'anémie
US20130116583A1 (en) * 2011-11-03 2013-05-09 Pacesetter, Inc. Systems and methods for predicting and corroborating pulmonary fluid overloads using an implantable medical device
US20140288551A1 (en) * 2013-03-15 2014-09-25 Pacesetter, Inc. Erythropoeitin production by electrical stimulation

Similar Documents

Publication Publication Date Title
US20210369167A1 (en) Using multiple diagnostic parameters for predicting heart failure events
US8494618B2 (en) Intracardiac impedance and its applications
US8849385B2 (en) Lead integrity testing during suspected tachyarrhythmias
EP2211702B1 (fr) Surveillance d'état hémodynamique sur la base d'une impédance intracardiaque ou vasculaire
EP2303403B1 (fr) Mémorisation d'électrogrammes pour des épisodes non physiologiques suspects
US20110106200A1 (en) Stroke risk monitoring system including implantable medical device
US9555249B2 (en) Assessment of cardiac wall motion using impedance measurements
US8380294B2 (en) Cardiac risk stratification
EP2187807B1 (fr) Systeme d'utilisation de multiples paramètres de diagnostic pour la prédiction d'événements d'insuffisance cardiaque
US8718769B2 (en) Monitoring ventricular capture of applied stimulation using sensed ventricular pressures
US20150157229A1 (en) Measuring atrial fibrillation burden using implantable device based sensors
US9839781B2 (en) Intracardiac impedance and its applications
US20230136130A1 (en) Hematocrit sensor based on impedance measurement in cardiovascular implantable electronic devices
EP2194865A1 (fr) Détection d'une aggravation d'insuffisance cardiaque selon des mesures d'impédance
WO2023073459A1 (fr) Capteur d'hématocrite reposant sur une mesure d'impédance dans des dispositifs électroniques implantables cardiovasculaires
WO2024020918A1 (fr) Discrimination entre une stimulation de la branche gauche du faisceau de his et une stimulation septale ventriculaire
US20220313105A1 (en) Medical device and method for impedance monitoring
CN117119954A (zh) 用于阻抗监测的医疗装置和方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22792912

Country of ref document: EP

Kind code of ref document: A1