Class / Patent application number | Description | Number of patent applications / Date published |
607008000 | Computing energy required or contact impedance | 29 |
20080249581 | PAIN FREE DEFIBRILLATION THRESHOLD ESTIMATION - This document discusses, among other things, a system and method for painlessly calculating an estimated defibrillation threshold, such as by using an implantable medical device and a controller. The estimated defibrillation threshold can be calculated using a delivered first energy to a first thoracic location, an electric field detected at a second thoracic location, and an electric field detected between a third thoracic location and a fourth thoracic location. The estimated defibrillation threshold represents an energy that, when delivered at the first thoracic location, can create an electric field strength in a target region of the heart that meets or exceeds a target electric field strength. | 10-09-2008 |
20080249582 | SELF-ADJUSTING OPTIMAL WAVEFORMS - An exemplary method includes detecting fibrillation, measuring impedance of a defibrillation circuit that includes myocardial tissue, determining one or more defibrillation shock parameters based at least in part on the impedance, delivering a defibrillation shock using the one or more defibrillation shock parameters and, if the shock was unsuccessful, adjusting a membrane time constant and determining one or more new defibrillation shock parameters based at least in part on the adjusted membrane time constant. Various other exemplary methods are disclosed as well as various exemplary devices, systems, etc. | 10-09-2008 |
20090099615 | High Accuracy Painless Method for Measuring Defibrillation Lead Impedance - Methods and apparatus for accurately and painlessly measuring the impedance between defibrillation electrodes implanted in a patient utilize a high current test pulse delivered with a sufficiently high current to produce an accurate measurement of the defibrillation electrode impedance while limiting the duration of the test pulse such that the pain sensing cells in the patient do not perceive the test pulse. In one embodiment, the test pulse is generated from the high voltage transformer without storing energy in the high voltage capacitors and is delivered to the defibrillation electrodes in the patient utilizing the high voltage switching circuitry. | 04-16-2009 |
20090177242 | Apparatus and method for non-invasive induction of ventricular fibrillation - An apparatus and method for delivering an external shock pulse receive pacing pulses generated by a first device and a shock pulse generated by a second device. An output of the apparatus is coupled to patient electrodes and the apparatus controls delivery of the received pacing pulses to the output and delivery of the received shock pulse to the output. A control module, pacing control and shock control included in the apparatus cooperatively control delivery of the received shock pulse to the output at a predetermined delay after one of the received pacing pulses. | 07-09-2009 |
20100087884 | CARDIAC RHYTHM MANAGEMENT SYSTEM WITH DEFIBRILLATION THRESHOLD PREDICTION - A cardiac rhythm management device predicts defibrillation thresholds without any need to apply defibrillation shocks or subjecting the patient to fibrillation. Intravascular defibrillation electrodes are implanted in a heart. By applying a small test energy, an electric field near one of the defibrillation electrodes is determined by measuring a voltage at a sensing electrode offset from the defibrillation electrode by a known distance. A desired minimum value of electric field at the heart periphery is established. A distance between a defibrillation electrodes and the heart periphery is measured, either fluoroscopically or by measuring a voltage at an electrode at or near the heart periphery. Using the measured electric field and the measured distance to the periphery of the heart, the defibrillation energy needed to obtain the desired electric field at the heart periphery is estimated. In an example, the device also includes a defibrillation shock circuit and a stimulation circuit. | 04-08-2010 |
20100114222 | LEAD INTEGRITY TESTING TRIGGERED BY SENSED ASYSTOLE - A method includes sensing a cardiac electrogram (EGM) signal of a patient via one or more electrodes on at least one implantable medical lead. An asystolic EGM signal is detected from the patient, and a lead integrity test of the at least one implantable medical lead is initiated in response to the asystolic EGM signal. | 05-06-2010 |
20100114223 | DETERMINING INTERCARDIAC IMPEDANCE - A system and method for determining complex intercardiac impedance to detect various cardiac functions are disclosed involving a signal generator means for providing an adjustable direct current signal, a modulator for modulating the adjustable direct current signal to produce a modulated signal, at least one electrode for propagating the modulated signal across a myocardium, at least one sensor for detecting an outputted modulated signal from the myocardium, and at least one circuit to reduce the influence of process noise (aggressors) in the outputted modulated signal. The at least one circuit comprises an amplifier, a demodulator, and an integrator. The amplitude and phase of the final outputted modulated signal indicate the complex impedance of the myocardium. Changes in the complex impedance patterns of the myocardium provide indication of reduced oxygen and blood flow to the myocardium. The apparatus can be employed in implantable devices, including cardiac pacemakers and implantable cardioverter defibrillators. | 05-06-2010 |
20100114224 | IMPLANTABLE MEDICAL DEVICE CROSSTALK EVALUATION AND MITIGATION - Electrical crosstalk between two implantable medical devices or two different therapy modules of a common implantable medical device may be evaluated, and, in some examples, mitigated. In some examples, one of the implantable medical devices or therapy modules delivers electrical stimulation to a nonmyocardial tissue site or a nonvascular cardiac tissue site, and the other implantable medical device or therapy module delivers cardiac rhythm management therapy to a heart of the patient. | 05-06-2010 |
20100125305 | USE OF IMPEDANCE TO ASSESS ELECTRODE LOCATIONS - A process for determining whether the location of a stimulation electrode meets a selected heart performance criteria includes providing stimulation to the heart through the electrode and obtaining an impedance measurement during stimulation delivery using an impedance sensing vector formed by electrodes that do not include the stimulation electrode. The impedance measurements are processed, either alone or in combination with an electrogram, also obtained during stimulation, to obtain a measure of hemodynamic performance. | 05-20-2010 |
20110098765 | DETECTING LEAD RELATED CONDITION DURING DELIVERY OF THERAPEUTIC ELECTRICAL SIGNALS - In general, the disclosure describes techniques for detecting lead related conditions, such as lead fractures or other lead integrity issues. As described herein, lead related conditions are identified by detecting delivered energy and electrical path impedance during delivery of a therapeutic electrical to a patient. If one or both of the delivered energy and impedance traverse respective thresholds, a lead related condition may exist. The energy delivered during the electrical signal may be compared to the amount of energy the electrical signal was programmed to deliver to determine if the delivered energy is less than a threshold percentage of the programmed energy of the electrical signal. The impedance of the electrical path through which the therapeutic electrical signal is delivered may be compared to a threshold impedance value to determine if the impedance detected during the electrical signal is greater than the threshold. | 04-28-2011 |
20110112594 | PAIN FREE DEFIBRILLATION THRESHOLD ESTIMATION - A system and method for painlessly calculating an estimated defibrillation threshold, such as by using an implantable medical device and a controller. The estimated defibrillation threshold can be calculated using a delivered first energy to a first thoracic location, an electric field detected at a second thoracic location, and an electric field detected between a third thoracic location and a fourth thoracic location. The estimated defibrillation threshold represents an energy that, when delivered at the first thoracic location, can create an electric field strength in a target region of the heart that meets or exceeds a target electric field strength. | 05-12-2011 |
20110213434 | Multiple Battery configurations in an Implantable Medical Device - Implantable medical device power circuits are disclosed. Multiple batteries may be provided, along with a number of switches, enabling a plurality of battery and power circuit configurations to be defined. Configurations of the power circuit may be changed in response to changes in battery status as the batteries are used and/or near end-of-life. Configurations of the power circuit may also be performed in response to changes in device operation. Methods associated with operating such circuits and implantable medical devices are also disclosed. | 09-01-2011 |
20110230925 | Electrode Delivery System - According to an aspect of the present disclosure, an automatic external defibrillator configured to deliver electrical pulses and/or shocks to a heart of a patient during a cardiac emergency is provided and includes a housing supporting an electrical connector; a defibrillator electrode delivery system supported on the housing; and a pair of defibrillation electrode pads supported by the defibrillator electrode delivery system. Each of the pair of defibrillation electrode pads is pre-connected to the electrical connector of the housing. A hydrogel layer of each defibrillation electrode pad is retained by the defibrillator electrode delivery system in such a manner so as to reduce a moisture vapor transmission rate thereof. | 09-22-2011 |
20120010673 | Method and apparatus for determining battery capacity in a defibrillator - A defibrillator system and associated methodology for determining capacity of a battery and/or a number of battery cells contained in a pack. The system measures and stores the battery or battery pack voltage signal data and uses an algorithm to determine the remaining capacity. The algorithm takes into account the operating mode of the device, historical information of the device including, but not limited to, how long it has been since the device has been used, how the device has been used (e.g. shocking mode or idle mode), how many times the device has been used with its installed battery or battery pack, how many charging cycles and/or shocks have been delivered etc. The output from the system is fed back to the user to inform the user when the battery is low, needs to be replaced and/or how many remaining shocks are left the battery. | 01-12-2012 |
20120158077 | IMPLANTABLE DEVICE - An implantable medical device configured to connect to function conductor(s) to transmit therapeutic signals or diagnostic signals or both. Includes a controllable voltage/current source or adjustable terminating impedance for the function conductor and a control unit that is connected to the voltage or current source or adjustable terminating impedance. The control unit controls a voltage, or a current to be applied to the function line, or to adjust the terminating impedance. Includes an interference field sensor connected to the control unit, and to detect an alternating electromagnetic or magnetic field, and to supply an output signal, upon detection. The control unit controls the voltage/current source as a function of the output signal of the interference field sensor, or sets the adjustable impedance so that a voltage induced as the result of an alternating electromagnetic or magnetic field is compensated for at the distal end of the electrode line. | 06-21-2012 |
20120191153 | DIAGNOSIS OF LEAD FRACTURE AND CONNECTION PROBLEMS - Techniques for diagnosing lead fractures and lead connection problems are described. One or more medical leads may be coupled to an implantable medical device (IMD) to position electrodes or other sensors at different locations within a patient than the IMD. The IMD may include a lead diagnostic module configured to diagnose problems with a coupled lead and automatically select between a lead fracture problem and a lead connection problem based on the diagnosis. The diagnosis of either lead fracture problems or lead connection problems may be based on a timing of an increased impedance value with respect to connection of the lead to the IMD, a return to baseline impedance values after the increased impedance value, an abrupt rise of the increased impedance value, maximum impedance values, or oversensing. An external device may present the diagnosis to a user to facilitate appropriate corrective action. | 07-26-2012 |
20130123871 | High Accuracy Painless Method for Measuring Defibrillation Lead Impedance - Methods and apparatus for accurately and painlessly measuring the impedance between defibrillation electrodes implanted in a patient utilize a high current test pulse delivered with a sufficiently high current to produce an accurate measurement of the defibrillation electrode impedance while limiting the duration of the test pulse such that the pain sensing cells in the patient do not perceive the test pulse. In one embodiment, the test pulse is generated from the high voltage transformer without storing energy in the high voltage capacitors and is delivered to the defibrillation electrodes in the patient utilizing the high voltage switching circuitry. | 05-16-2013 |
20130261686 | SHOCK TIMING TECHNOLOGY - A method for accurately determining timing points for T-wave shocks is particularly useful in a system for determining a cardiac shock strength in an implantable cardioverter defibrillator (ICD. The method involves acquiring at least one first signal, acquiring at least a second signal, comparing the signals, and selecting a timing point with the T-wave of the signal. The first and second signals may be two different aspects of a single electrogram, first and second electrograms, or a combination thereof. Comparison preferably involves signal alignment and qualitative analysis. | 10-03-2013 |
20140052206 | SYSTEM AND METHOD FOR GRAPHICALLY CONFIGURING LEADS - Systems and methods are provided for graphically configuring leads for a medical device. According to one aspect, the system generally comprises a medical device and a processing device, such as a programmer or computer, adapted to be in communication with the medical device. The medical device has at least one lead with at least one electrode in a configuration that can be changed using the processing device. The processing device provides a graphical display of the configuration, including a representative image of a proposed electrical signal to be applied by the medical device between the at least one electrode of the medical device and at least one other electrode before the medical device applies the electrical signal between the at least one electrode and the at least one other electrode. In one embodiment, the graphical display graphically represents the lead(s), the electrode(s), a pulse polarity, and a vector. | 02-20-2014 |
20140094869 | PREVENTING USE OF SYNC MODE DURING CARDIOVERSION AND DEFIBRILLATION - An external defibrillator may have a controller to set the defibrillator in a synchronous shock operating mode or an asynchronous shock operating mode, a shock module to cause the defibrillator to deliver shock therapy to a patient according to the present operating mode of the defibrillator, and a heart rhythm detector to detect a heart rhythm of the patient. The defibrillator may also have a mode assessment module to determine whether the present operating mode or selected defibrillation energy of the defibrillator is appropriate based on the detected heart rhythm of the patient. | 04-03-2014 |
20140214107 | DYNAMIC BATTERY MANAGEMENT IN AN IMPLANTABLE DEVICE - One aspect of this disclosure relates to a system for dynamic battery management in implantable medical devices. An embodiment of the system includes two or more devices for measuring battery capacity for an implantable medical device battery. The embodiment also includes a controller connected to the measuring devices. The controller is adapted to combine the measurements from the measuring devices using a weighted average to determine battery capacity consumed. According to various embodiments, at least one of the measuring devices includes a coulometer. At least one of the measuring devices includes a capacity-by-voltage device, according to an embodiment. The system further includes a display in communication with the controller in various embodiments. The display is adapted to provide a depiction of battery longevity in units of time remaining in the life of the implantable medical device battery, according to various embodiments. Other aspects and embodiments are provided herein. | 07-31-2014 |
20140257422 | DETECTION OF REDUCED DEFIBRILLATION PAD CONTACT - A system and method of detecting a loss of electrical contact between a pair of electrodes that are electrically coupled to skin of a subject. The method includes monitoring parameters of a transthoracic impedance between the pair of electrodes in at least one of a low frequency regime and a high frequency regime, detecting an occurrence of chest compressions based on a signal indicative of chest compressions, establishing baseline levels of the parameters in at least one of the low and high frequency regimes, detecting whether changes in at least one parameter exceeds the baseline level by a threshold, determining that at least one electrode of the pair of electrodes is losing electrical contact with the skin responsive to the at least one parameter exceeding the baseline level by the threshold, and issuing an alert in response to a determination that the at least one electrode is losing electrical contact. | 09-11-2014 |
20140277229 | IDENTIFICATION OF INSULATION BREACH USING ELECTROGRAMS - An implantable medical device capable of sensing cardiac signals and delivering cardiac electrical stimulation therapies is enabled to detect a short circuit condition. In one embodiment, a cardiac signal is sensed by a sensing module coupled to electrodes. A controller identifies signal events in response to the cardiac signal and detects a short circuit condition in response to at least one of the signal events having an amplitude crossing a short circuit detection threshold and a maximum of two signal events crossing the short circuit detection threshold occurring between two adjacent events having amplitudes not crossing the short circuit detection threshold. In one embodiment, the signal events are identified from a differential signal determined from the sensed cardiac signal. | 09-18-2014 |
20140277230 | ELECTRICAL ENERGY DELIVERY TISSUE SITE VALIDATION - Electrical energy delivery tissue site validation systems and methods can determine an indication of a tissue type at a tissue site. This information can be used to enable or inhibit electrical energy delivery to the tissue site. The tissue type at the tissue site can be determined such as by delivering a test electrical energy and sensing a responsive electrical energy. An electrical connectivity to the tissue site can also be determined, such as by using a sensed intrinsic electrical signal at the tissue site. Tissue type information may be communicated externally, such as to allow user confirmation or override of the determined indication of tissue type at the tissue site, such as by a physician, user, or other operator. | 09-18-2014 |
20140324113 | DEVICE AND METHOD FOR REDUCING PATIENT TRANSTHORACIC IMPEDANCE FOR THE PURPOSE OF DELIVERING A THERAPEUTIC CURRENT - A device and method for reducing patient transthoracic impedance for the purpose of delivering a therapeutic current are provided. In one embodiment, the device for reducing patient transthoracic impedance for the purpose of delivering a therapeutic current may be used in a defibrillator. The device for reducing patient transthoracic impedance for the purpose of delivering a therapeutic current may be a microneedle array that may have a number of different configurations and may be made with different materials. | 10-30-2014 |
20150088215 | EXTERNAL DEFIBRILLATOR - An external defibrillator includes patient electrodes ( | 03-26-2015 |
20160038750 | DEFIBRILLATOR AND METHOD OF CONTROLLING DEFIBRILLATOR - A defibrillator includes: an impedance measuring section which is configured to obtain an impedance measurement value between a living body of a rescue target and electrodes; a controller which is configured to detect a kind of the electrodes, and which, based on the detected kind of the electrodes, is configured to perform determination of whether the impedance measurement value is to be output or not; and an outputting section which, based on the determination, is configured to output the impedance measurement value. | 02-11-2016 |
20160059023 | Impedance Spectroscopy for Defibrillator Applications - A computing device includes a memory configured to store instructions. The computing device also includes a processor to execute the instructions to perform operations that include providing an alternating electrical signal to a patient through at least a pair of electrodes, and determining transthoracic impedance of the patient from a measurement associated with the applied alternating electrical signal. Operations also include identifying, from the transthoracic impedance, a sequence of resistance values for controlling the discharge of a charge storage device located external to the patient, and controlling the discharge of the charge storage device using the identified sequence of resistance values. | 03-03-2016 |
20160067507 | IMPLANTABLE MEDICAL DEVICES HAVING MULTI-CELL POWER SOURCES - An implantable medical device includes a low-power circuit and a multi-cell power source. The cells of the power source are coupled in a parallel configuration. The implantable medical device includes both a low power circuit that is selectively coupled between the first and second cells and a high power output circuit that is directly coupled to the first and second cells in a parallel configuration. An isolation circuit is coupled to the first cell, the second cell and the low power circuit to maintain a current isolation between the first cell and the second cell at least during delivery of current having a large magnitude to the high power output circuit. | 03-10-2016 |