Patent application number | Description | Published |
20090248114 | REVERSIBLE IMPLANTABLE ACOUSTIC SENSOR - An implantable medical device having an acoustic element includes a control module coupled to the acoustic element, an acoustic sensing module coupled to the control module, and a patient alert driver module coupled to the control circuit. The patient alert driver module generates a patient alert drive signal for activating the acoustic element to emit a patient alert signal. The control module includes an isolation circuit for isolating the acoustic sensing module from the acoustic element in response to the patient alert drive signal. | 10-01-2009 |
20100179444 | IMPLANTABLE MEDICAL DEVICE WITH ADAPTIVE SIGNAL PROCESSING AND ARTIFACT CANCELLATION - A medical device having a sensor sensing an n-dimensional signal during a first known variable condition and during a second known variable condition different from the first known variable condition, a processor performing principal component analysis (PCA) on the sensed n-dimensional signal to generate a first template corresponding to a principal component of variation associated with the first known variable condition and a second template corresponding to a principal component of variation associated with the second known variable condition, a storage device storing the first template and the second template, and a controller detecting a patient condition in response to the stored templates. | 07-15-2010 |
20100179445 | IMPLANTABLE MEDICAL DEVICE WITH ADAPTIVE SIGNAL PROCESSING AND ARTIFACT CANCELLATION - A medical device includes one or more sensors used to acquire a multi-dimensional signal. In one embodiment, principal component analysis is performed on the multi-dimensional signal to produce signal data. The principal component analysis results are used to cancel signal artifact in one embodiment. A medical device controller produces one of a therapy control and a diagnostic output in response to the signal data. | 07-15-2010 |
20100179611 | IMPLANTABLE MEDICAL DEVICE WITH ADAPTIVE SIGNAL PROCESSING AND ARTIFACT CANCELLATION - A medical device includes one or more sensors used to acquire a multi-dimensional signal. In one embodiment, principal component analysis is performed on the multi-dimensional signal to produce signal data. The principal component analysis results are used to cancel signal artifact in one embodiment. A medical device controller produces one of a therapy control and a diagnostic output in response to the signal data. | 07-15-2010 |
20100317937 | Device and Method for Monitoring of Absolute Oxygen Saturation and Total Hemoglobin Concentration - A medical device for monitoring of oxygen saturation includes an optical sensor adapted for positioning adjacent to a tissue volume. The optical sensor has a light emitting portion capable of emitting light at a plurality of wavelengths and a light detecting portion capable of generating an electrical output signal corresponding to light incident on the detecting portion. A control module coupled to the optical sensor controls the light emitted by the light emitting portion. A monitoring module receives the output signal from the light detecting portion and computes a volume-independent measure of oxygen saturation in the volume of tissue using the output signal. | 12-16-2010 |
20100317940 | Absolute calibrated tissue oxygen saturation and total hemoglobin volume fraction - A medical device for monitoring a patient condition includes a sensor capable of being advanced transvascularly to be positioned along a volume of tissue, the sensor including a first combination of a light source and a light detector to emit light into a volume of tissue and to detect light scattered by the volume of tissue and to generate a first output signal corresponding to an intensity of the detected light. A control module is coupled to the light source to control the light source to emit light at least four spaced-apart light wavelengths, and a monitoring module is coupled to the light detector to receive the output signal and compute a measure of tissue oxygenation using the light detector output signal. | 12-16-2010 |
20100317941 | ABSOLUTE CALIBRATED TISSUE OXYGEN SATURATION AND TOTAL HEMOGLOBIN VOLUME FRACTION - A medical device for monitoring a patient condition includes a first combination of a light source and a light detector to emit light into a volume of tissue, detect light scattered by the volume of tissue, and provide a first output signal corresponding to an intensity of the detected light. A control module is coupled to the light source to control the light source to emit light at least four spaced-apart light wavelengths, and a monitoring module is coupled to the light detector to receive the output signal, compute a measure of tissue oxygenation in response to the light detector output signal, and detect tissue hypoxia using the measure of tissue oxygenation. | 12-16-2010 |
20100317942 | Tissue Oxygenation Monitoring in Heart Failure - A medical device system and associated method are used for monitoring a heart failure patient. A medical device for monitoring delivery of a therapy includes a sensor sensing an optical sensor signal corresponding to light attenuation by a volume of body tissue of a patient, a therapy delivery module to deliver a therapy, and a processor configured to compute a first tissue oxygenation measurement from the optical sensor signal prior to initiating delivery of the therapy, compute a second tissue oxygenation measurement from the optical sensor signal subsequent to initiating delivery of the therapy, compare the first and the second tissue oxygenation measurements, and determine whether the delivered therapy was successful in response to the first tissue oxygenation measurement and the second tissue oxygenation measurement. | 12-16-2010 |
20100317943 | Active Noise Cancellation in an Optical Sensor Signal - A medical device system and associated method are used for monitoring tissue oxygenation. An optical sensor produces a signal corresponding to tissue light attenuation. A processor receives the optical sensor signal and computes a first measure of light attenuation at a first light wavelength and a second measure of light attenuation at a second light wavelength. In one embodiment, noise cancellation circuitry receives the first measure and the second measure and generates a guessed ratio of the first and second measures. Using the first measure, the second measure and the guessed ratio, the noise cancellation circuitry provides a peak output power when the guessed ratio corresponds to an actual ratio of the first and second measures. | 12-16-2010 |
20100317946 | Shock Reduction Using Absolute Calibrated Tissue Oxygen Saturation and Total Hemoglobin Volume Fraction - An implantable medical device for detecting and treating an arrhythmia includes an optical sensor adapted for positioning adjacent to a blood-perfused tissue volume. In one embodiment for controlling arrhythmia therapies delivered by the device, the optical sensor is controlled to emit light in response to detecting an arrhythmia, detect light scattered by the volume of blood perfused tissue including measuring an optical sensor output signal corresponding to the intensity of scattered light for at least four spaced-apart wavelengths, and compute a volume-independent measure of tissue oxygen saturation from the detected light. The hemodynamic status of the arrhythmia is detected in response to the measure of tissue oxygen saturation. | 12-16-2010 |
20100317947 | Tissue Oxygenation Monitoring in Heart Failure - A medical device system and associated method control the delivery of a therapy to a patient. The system includes an activity sensor and detects a change in activity level of the patient. The system further include an optical sensor to sense signal corresponding to tissue light attenuation. The system computes a tissue oxygenation measurement in response to detecting a change in activity level. A parameter controlling delivery of the therapy is adjusted in response to detecting the decreased tissue oxygenation. | 12-16-2010 |
20100318146 | Tissue Oxygenation Monitoring in Heart Failure - A medical device for monitoring delivery of a therapy that includes a therapy delivery module to deliver a therapy, a controller to set a therapy delivery control parameter, an optical sensor to produce a signal corresponding to tissue light attenuation, and a processor configured to compute a tissue oxygenation measurement from the optical sensor signal, wherein the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation. | 12-16-2010 |
20100318149 | Shock Reduction Using Absolute Calibrated Tissue Oxygen Saturation and Total Hemoglobin Volume Fraction - An implantable medical device that includes an optical sensor for providing a signal corresponding to light attenuation by a volume of blood perfused tissue, a control module coupled to the optical sensor controlling the light emitted by the optical sensor, a monitoring module receiving an optical sensor output signal and measuring light attenuation, a tissue electrode for stimulating the volume of blood perfused tissue, a pulse generator coupled to the tissue electrode for delivering electrical stimulation to the volume of blood-perfused tissue, and a processor coupled to the cardiac electrode and the monitoring module and configured to detect an arrhythmia in response to the depolarization signals, compute a tissue oxygenation measurement and control the pulse generator to deliver electrical stimulation to the volume of blood-perfused tissue in response to detecting the arrhythmia, and detect a hemodynamic status of the arrhythmia in response to at least one of a detected rate of tissue oxygenation decline and a detected rate of tissue oxygenation recovery. | 12-16-2010 |
20100331903 | HEART SOUND SENSING TO REDUCE INAPPROPRIATE TACHYARRHYTHMIA THERAPY - Techniques for detecting heart sounds to reduce inappropriate tachyarrhythmia therapy are described. In some examples, a medical device determines that a cardiac rhythm of the patient is treatable with a therapy, such as a defibrillation pulse, based on a cardiac electrogram (EGM). The medical device analyzes detected heart sounds, and withholds or allows the therapy based on the analysis of the heart sounds. | 12-30-2010 |
20110066198 | METHOD AND APPARATUS FOR POST-SHOCK EVALUATION USING TISSUE OXYGENATION MEASUREMENTS - A method and device for delivering therapy that includes an electrode to sense cardiac signals and to deliver a therapy, a therapy delivery module coupled to the electrode to deliver a therapy via the electrode in response to the sensed cardiac signals, a sensor emitting light and detecting emitted light scattered by a tissue volume adjacent the optical sensor to generate a corresponding detected light intensity output signal, a control module coupled to the sensor to control light emission of the sensor in response to delivering the therapy, and a controller coupled to the therapy delivery module and the sensor, the controller configured to determine tissue oxygenation measurements in response to the output signal, determine a tissue oxygenation trend in response to the tissue oxygenation measurements, and determine whether the delivered therapy restored cardiac hemodynamic function in response to the determined tissue oxygenation trend. | 03-17-2011 |
20110066204 | METHOD AND APPARATUS FOR POST-SHOCK EVALUATION USING TISSUE OXYGENATION MEASUREMENTS - A method and device for delivering therapy that includes an electrode to sense cardiac signals and to deliver a therapy, a therapy delivery module coupled to the electrode to deliver a therapy via the electrode in response to the sensed cardiac signals, a sensor emitting light and detecting emitted light scattered by a tissue volume adjacent the sensor to generate a corresponding detected light intensity output signal, a control module coupled to the sensor to control light emission of the sensor in response to delivering the therapy; and a controller coupled to the therapy delivery module and the sensor, the controller configured to determine a tissue oxygenation measurement in response to the output signal, and determine whether the delivered therapy was successful in restoring cardiac hemodynamic function in response to the tissue oxygenation measurement. | 03-17-2011 |
20110066206 | METHOD AND APPARATUS FOR POST-SHOCK EVALUATION USING TISSUE OXYGENATION MEASUREMENTS - A method and device for delivering therapy that includes an electrode to sense cardiac signals and to deliver a therapy, a monitoring module detecting a cardiac event in response to the sensed cardiac signals using first detection criteria, a sensor emitting light and detecting emitted light scattered by a tissue volume adjacent the sensor to generate a corresponding detected light intensity output signal, a control module coupled to the sensor to control light emission of the sensor in response to delivering the therapy, and a controller coupled to the monitoring module, the therapy delivery module and the sensor, the controller configured to determine tissue oxygenation measurements in response to the output signal, determine a tissue oxygenation trend in response to the tissue oxygenation measurements, determine a recovery index in response to the determined tissue oxygenation trend, and control one or both of detecting a cardiac event by the monitoring module and delivery of therapy by the therapy delivery module in response to the determined recovery index. | 03-17-2011 |
20120109258 | DETERMINATION OF DIPOLE FOR TISSUE CONDUCTANCE COMMUNICATION - Aspects of the present disclosure include a medical device system including an implantable medical device and an external device with three or more electrodes configured to contact a patient's skin. The external device either transmits or receives a test signal to or from the implantable medical device using a plurality of possible receive dipoles, where each possible receive dipole is formed by a pair of electrodes. A signal quality monitor, either at the implantable medical device or at the external device, measures a signal quality for the possible receive dipoles. | 05-03-2012 |
20120130208 | COEFFICENT DETERMINATION FOR BLOOD OXYGEN SATURATION AND TOTAL HEMOGLOBIN CONCENTRATION INDICES - A first concentration of a chromophore corresponding to a measurement volume of an optical sensor is determined. A second concentration of the chromophore is obtained in the vicinity of the measurement volume corresponding to a change in at least one of a total concentration of the chromophore and a relative concentration of a first form of the chromophore to the total concentration of the chromophore in the measurement volume. Light remittance measurements including a first light wavelength and a second light wavelength are obtained corresponding to the first chromophore concentration and the second chromophore concentration. A coefficient for computing an index of a change in the chromophore concentration is computed using the difference between the first and second chromophore concentrations and the first and second light remittance measurements. | 05-24-2012 |
20120296228 | HEART SOUNDS-BASED PACING OPTIMIZATION - An implantable medical device receives both heart sound and electrogram signals. A processor within the implantable medical device extracts physiologically relevant information from both the heart sound signal and the electrogram signal. Based on the extracted physiologically relevant information a set of pacing parameters is evaluated. In certain examples, the values of the pacing parameters may be changed by the implantable medical device in response to the physiologically relevant information extracted from the heart sound signal and the electrogram signal. | 11-22-2012 |
20130197597 | TECHNIQUES FOR MITIGATING MOTION ARTIFACTS FROM IMPLANTABLE PHYSIOLOGICAL SENSORS - Disclosed techniques include monitoring a physiological characteristic of a patient with a sensor that is mounted to an inner wall of a thoracic cavity of the patient, and sending a signal based on the monitored physiological characteristic from the sensor to a remote device. | 08-01-2013 |