Patent application number | Description | Published |
20090018404 | Cardiovascular Autonomic Neuropathy Testing Utilizing an Implantable Medical Device - A test system and method for cardiovascular autonomic neuropathy that incorporates an implanted medical device. One aspect of the invention relates to a system for performing cardiovascular autonomic neuropathy (CAN) testing in a diabetic patient having an implantable medical device (IMD) that includes a plurality of implantable physiological sensors and that is configured to transmit a wireless signal corresponding to a sensed physiological activity and to receive wireless signals. The system further includes one or more non-implantable physiological sensors, where the non-implantable physiological sensors are each configured to transmit a signal corresponding to a sensed physiological parameter, and a monitor device having a patient interface. The monitor device is configured to interface with a patient, including directing the patient to answer health related questions and use one or more of the non-implantable physiological sensors. The monitor device is also configured to receive signals, including signals from the IMD and the non-implantable physiological sensors. The system is configured to provide an indication of the presence or progression of CAN. | 01-15-2009 |
20090076557 | Closed Loop Cardiac Resynchronization Therapy Using Cardiac Activation Sequence Information - Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed to detect, monitor, track and/or trend closed-loop cardiac resynchronization therapy using cardiac activation sequence information. Devices and methods involve sensing a plurality of composite cardiac signals using a plurality of electrodes, the electrodes configured for implantation in a patient. A source separation is performed using the sensed plurality of composite cardiac signals, producing one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences. A cardiac resynchronization therapy is adjusted using one or both of the one or more cardiac signal vectors and the signals associated with the one or more cardiac signal vectors. In further embodiments, the cardiac resynchronization therapy may be initiated, terminated, or one or more parameters of the resynchronization therapy may be altered. | 03-19-2009 |
20090198301 | Automatic Capture Verification using Electrocardiograms Sensed from Multiple Implanted Electrodes - Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed for automatic capture verification using cardiac activation sequence information. Devices and methods sense composite cardiac signals using implantable electrodes. A source separation is performed using the composite signals. One or more signal vectors are produced that are associated with all or a portion of one or more cardiac activation sequences based on the source separation. A cardiac response to the pacing pulses is classified using characteristics associated with cardiac signal vectors and the signals associated with the vectors. Further embodiments may involve classifying the cardiac response as capture or non-capture, fusion or intrinsic cardiac activity. The characteristics may include an angle or an angle change of the cardiac signal vectors, such as a predetermined range of angles of the one or more cardiac signal vectors. | 08-06-2009 |
20090306486 | SENSING VECTOR CONFIGURATION IN ICD TO ASSIST ARRHYTHMIA DETECTION AND ANNOTATION - An apparatus comprises an implantable cardiac signal sensing circuit, configured to provide a sensed near-field depolarization signal from a ventricle and to provide a sensed a far-field intrinsic atrial signal using a far-field atrial sensing channel, and a controller circuit communicatively coupled to the cardiac signal sensing circuit. The controller circuit includes a P-wave detection module configured to detect an atrial depolarization in the sensed far-field intrinsic atrial signal and a tachyarrhythmia detection module configured to detect an episode of tachyarrhythmia using the sensed near-field depolarization signal and to determine whether the tachyarrhythmia episode is indicative of supraventricular tachycardia (SVT) using the detected atrial depolarization and the sensed near-field depolarization signal. | 12-10-2009 |
20100125306 | MASS ATTRIBUTE DETECTION THROUGH PHRENIC STIMULATION - According to certain examples, an implanted medical device is used to determine a mass attribute of a patient. The patient's phrenic nerve is stimulated, and the diaphragmatic response is measured by an accelerometer. The measured response is analyzed in certain embodiments to determine a mass attribute. This information can help in the diagnosis of, and efficient response to, edema. | 05-20-2010 |
20100262204 | Anodal Stimulation Detection and Avoidance - Cardiac resynchronization therapy is delivered to a heart using an extended bipolar electrode configuration in accordance with programmed pacing parameters including a non-zero intraventricular delay. The extended bipolar electrode configuration comprises a left ventricular electrode defining a cathode of the extended bipolar electrode configuration and a right ventricular electrode defining an anode of the extended bipolar electrode configuration. A pace pulse is delivered to the left ventricular electrode and anodal stimulation of the right ventricle is detected based on the sensed response to the pace pulse. | 10-14-2010 |
20100298729 | Cardiac Activation Sequence Monitoring for Ischemia Detection - Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed to detect, monitor, track and/or trend ischemia using cardiac activation sequence information. Ischemia detection may involve sensing composite cardiac signals using implantable electrodes, and performing a signal separation that produces one or more cardiac activation signal vectors associated with one or more cardiac activation sequences. A change in the signal vector may be detected using subsequent separations. The change may be an elevation or depression of the ST segment of a cardiac cycle or other change indicative of myocardial ischemia, myocardial infarction, or other pathological change. The change may be used to predict, quantify, and/or qualify an event such as an arrhythmia, a myocardial infarction, or other pathologic change. Information associated with the vectors may be stored and used to track the vectors. | 11-25-2010 |
20100305637 | Respiration Sensor Processing for Phrenic Nerve Activation Detection - An implantable cardiac device includes a sensor for sensing patient respiration and detecting phrenic nerve activation. A first filter channel attenuates first frequencies of the sensor signal to produce a first filtered output. A second filter channel attenuates second frequencies of the respiration signal to produce a second filtered output. Patient activity is evaluated using the first filtered output and phrenic nerve activation caused by cardiac pacing is detected using the second filtered output. | 12-02-2010 |
20100305638 | Method and Apparatus for Phrenic Nerve Activation Detection with Respiration Cross-Checking - The present invention concerns phrenic nerve activation detection algorithms for characterization of phrenic nerve activation and phrenic nerve activation avoidance in cardiac pacing therapy. | 12-02-2010 |
20100305647 | Activity Sensor Processing for Phrenic Nerve Activation Detection - An implantable cardiac device includes a sensor for sensing patient activity and detecting phrenic nerve activation. A first filter channel attenuates first frequencies of the sensor signal to produce a first filtered output. A second filter channel attenuates second frequencies of the accelerometer signal to produce a second filtered output. Patient activity is evaluated using the first filtered output and phrenic nerve activation caused by cardiac pacing is detected using the second filtered output. | 12-02-2010 |
20110098773 | ESTIMATION OF DEDICATED BIPOLAR PACING VECTOR THRESHOLD - Methods and devices are described that allow estimation of an electrostimulation capture threshold, such as a dedicated bipolar pacing vector threshold. In an example, an equal-energy assumption between first and second pacing vectors can be used to estimate an electrostimulation capture threshold of a second pacing vector from a measured electrostimulation capture threshold of the first pacing vector and impedances of the first and second pacing vectors. In an example, a relationship between first and second pacing vectors can be determined from measured data, and a parameter of the relationship can be used with a measurement of an electrostimulation capture threshold of the first pacing vector to estimate an electrostimulation capture threshold of the second pacing vector. | 04-28-2011 |
20110098774 | ESTIMATION OF DEDICATED BIPOLAR PACING VECTOR THRESHOLD - Methods and devices are described that allow estimation of an electrostimulation capture threshold, such as a dedicated bipolar pacing vector threshold. In an example, an equal-energy assumption between first and second pacing vectors can be used to estimate an electrostimulation capture threshold of a second pacing vector from a measured electrostimulation capture threshold of the first pacing vector and impedances of the first and second pacing vectors. In an example, a relationship between first and second pacing vectors can be determined from measured data, and a parameter of the relationship can be used with a measurement of an electrostimulation capture threshold of the first pacing vector to estimate an electrostimulation capture threshold of the second pacing vector. | 04-28-2011 |
20110137192 | Arrhythmia Discrimination using ECG's Sensed from Multiple Implanted Electrodes - Cardiac monitoring and/or stimulation methods and systems provide for monitoring, diagnosing, defibrillation and pacing therapies, or a combination of these capabilities, including cardiac systems incorporating or cooperating with neuro-stimulating devices, drug pumps, or other therapies. Embodiments of the present invention relate generally to implantable medical devices employing automated cardiac activation sequence monitoring and/or tracking for arrhythmia discrimination. Embodiments of the invention are directed to devices and methods involving sensing a plurality of composite cardiac signals using a plurality of implantable electrodes. A source separation is performed using the sensed plurality of composite cardiac signals and the separation produces one or more cardiac signal vectors associated with one or more cardiac activation sequences that is indicative of ischemia. A change of the one or more cardiac signal vectors is detected using the one or more cardiac signal vectors. Cardiac arrhythmias are discriminated using the one or more cardiac signal vectors. | 06-09-2011 |
20110245890 | METHOD AND APPARATUS FOR PACING SAFETY MARGIN - An apparatus comprises a cardiac signal sensing circuit, a pacing therapy circuit, and a controller circuit. The controller circuit includes a safety margin calculation circuit. The controller circuit initiates delivery of pacing stimulation energy to the heart using a first energy level, changes the energy level by at least one of: a) increasing the energy from the first energy level until detecting that the pacing stimulation energy induces stable capture, or b) reducing the energy from the first energy level until detecting that the stimulation energy fails to induce capture, and continues changing the stimulation energy level until confirming stable capture or the failure of capture. The safety margin calculation circuit calculates a safety margin of pacing stimulation energy using at least one of a determined stability of a parameter associated with evoked response and a determined range of energy levels corresponding to stable capture or intermittent failure of capture. | 10-06-2011 |
20120035685 | USER INTERFACE SYSTEM FOR USE WITH MULTIPOLAR PACING LEADS - An interactive representation of electrostimulation electrodes or vectors can be provided, such as for configuring combinations of electrostimulation electrodes. In an example, electrodes or test parameters can be presented graphically or in a table. A user interface can be configured to receive user-input designating electrode combinations or vectors for test or for use in programming an implantable or ambulatory medical device. The interface can be used to indicate suggested electrode combinations or vectors in response to a first selection of an electrode. Tests can be performed on electrode combinations and vectors, and the results of the tests can be presented to a user using the interactive representation. In an example, test results can be analyzed by a processor and optionally used to program an implantable or ambulatory medical device. | 02-09-2012 |
20120130442 | CARDIAC ANODAL ELECTROSTIMULATION DETECTION - Cardiac anodal electrostimulation detection systems and methods are described, such as for distinguishing between cathodal-only capture and at least partially anodal capture (e.g., combined anodal and cathodal capture, or between two anodes of which only one captures nearby cardiac tissue, etc.). | 05-24-2012 |
20130190636 | OPTIMIZATION OF LV AND RV LEAD PLACEMENT BASED ON ELECTRICAL DELAYS - A system comprises a cardiac signal sensing and a processing circuit. The cardiac signal sensing circuit senses a first cardiac signal segment that includes a QRS complex and a second cardiac signal segment that includes a fiducial indicative of local ventricular activation. The processor circuit includes a site activation timer circuit configured to determine a time duration between a fiducial of the QRS complex of the first cardiac signal segment and the fiducial of the second cardiac signal segment. The processor circuit is configured to generate, using the determined time duration, an indication of optimality of placement of one or more electrodes for delivering therapy and provide the indication to at least one of a user or process. | 07-25-2013 |