Patent application number | Description | Published |
20080249583 | THERAPY CONTROL BASED ON THE RATE OF CHANGE OF INTRACARDIAC IMPEDANCE - A system comprising a medical device that includes an impedance measurement circuit adapted to be coupled to implantable electrodes to obtain an intracardiac impedance signal between electrodes, a therapy circuit operable to deliver a therapy to a subject, and a controller circuit coupled to the impedance measurement circuit and the therapy circuit. The controller circuit determines a time rate of change of the intracardiac impedance signal and adjusts at least one parameter related to therapy in a manner that alters the rate of change. | 10-09-2008 |
20080262559 | Method and apparatus for adjusting the sensing threshold of a cardiac rhythm management device - A method and apparatus for automatically adjusting the sensing threshold of cardiac rhythm management devices. The invention is particularly suited for implementation in devices such as implantable cardiac pacemakers and implantable cardioverter/defibrillators. A method and apparatus are provided in which a noise level and signal level for a sensing channel are determined for each cardiac cycle with the sensing threshold of the channel being adjusted in accordance therewith. | 10-23-2008 |
20080312548 | Methods and systems for implantably monitoring external breathing therapy - An implantable device is used to monitor one or more conditions associated with an external breathing therapy delivered to the patient. The device may monitor therapy parameters including therapy effectiveness, impact of the therapy on the patient, therapy usage, compliance with a prescribed usage, therapy interactions, and/or other parameters. | 12-18-2008 |
20090076563 | METHOD AND APPARATUS FOR TREATING IRREGULAR VENTRICULAR CONTRACTIONS SUCH AS DURING ATRIAL ARRHYTHMIA - A cardiac rhythm management system is capable of treating irregular ventricular heart contractions, such as during atrial tachyarrhythmias such as atrial fibrillation. A first indicated pacing interval is computed based at least partially on a most recent V-V interval duration between ventricular beats and a previous value of the first indicated pacing interval. Pacing therapy is provided based on either the first indicated pacing interval or also based on a second indicated pacing interval, such as a sensor-indicated pacing interval. A weighted averager such as an infinite impulse response (IIR) filter adjusts the first indicated pacing interval for sensed beats and differently adjusts the first indicated pacing interval for paced beats. The system regularizes ventricular rhythms by pacing the ventricle, but inhibits pacing when the ventricular rhythms are stable. | 03-19-2009 |
20090112116 | System And Method For Discrimination Of Central And Obstructive Disordered Breathing Events - Disordered breathing events may be classified as central, obstructive or a combination of central an obstructive in origin based on patient motion associated with respiratory effort. Central disordered breathing is associated with disrupted respiration with reduced respiratory effort. Obstructive disordered breathing is associated with disrupted respiration accompanied by respiratory effort. A disordered breathing classification system includes a disordered breathing detector and a respiratory effort motion sensor. Components of the disordered breathing classification system may be fully or partially implantable. | 04-30-2009 |
20090177702 | Medical Event Logbook System and Method - An event-based approach to collecting and organizing information associated with events affecting respiration is presented. The detection or prediction of an event affecting the respiration of a patient initiates acquisition of information associated with the event. The respiratory logbook system acquires information associated with the event during the event and during intervals proximate in time to the event. The information is organized as a respiratory log entry. The user can access the information by operating a user interface. The information may be presented in textual or graphical form. | 07-09-2009 |
20090326599 | CALIBRATION OF IMPEDANCE MONITORING OF RESPIRATORY VOLUMES USING THORACIC D.C. IMPEDANCE - A system includes an implantable medical device that includes a trans-thoracic impedance measurement circuit providing a trans-thoracic impedance signal of a subject. A controller is coupled to the trans-thoracic impedance circuit. The controller extracts a respiration signal from the trans-thoracic impedance signal, measures a breathing volume of the subject using the amplitude of the respiration signal and a breathing volume calibration factor, computes an adjusted breathing volume calibration factor using a reference baseline value of the trans-thoracic impedance and a measured baseline value of the trans-thoracic impedance, and computes a calibrated breathing volume using the adjusted breathing volume calibration factor. | 12-31-2009 |
20100056884 | THORACIC OR INTRACARDIAC IMPEDANCE DETECTION WITH AUTOMATIC VECTOR SELECTION - This document discusses, among other things, a cardiac function management device or other implantable medical device that includes a test mode and a diagnostic mode. During a test mode, the device cycles through various electrode configurations for collecting thoracic impedance data. At least one figure of merit is calculated from the impedance data for each such electrode configuration. In one example, only non-arrhythmic beats are used for computing the figure of merit. A particular electrode configuration is automatically selected using the figure of merit. During a diagnostic mode, the device collects impedance data using the selected electrode configuration. In one example, the figure of merit includes a ratio of a cardiac stroke amplitude and a respiration amplitude. Other examples of the figure of merit are also described. | 03-04-2010 |