Patent application number | Description | Published |
20080221636 | METHOD AND APPARATUS FOR CLOSED-LOOP INTERMITTENT CARDIAC STRESS AUGMENTATION PACING - A cardiac pacing system controls the progression of a cardiac disorder such as heart failure by delivering cardiac pacing to create or augment regional stress in the heart. The cardiac pacing is delivered intermittently, such as on a periodic basis, according to a cardiac stress augmentation pacing sequence that includes alternating pacing and non-pacing periods. One or more physiological signals are monitored for closed-loop control of the cardiac pacing using baseline characteristics of the cardiac disorder, acute cardiac stress created by the cardiac pacing, and/or risk associated with the cardiac pacing. | 09-11-2008 |
20080249586 | CARDIOPULMONARY FUNCTIONAL STATUS ASSESSMENT VIA METABOLIC RESPONSE DETECTION BY IMPLANTABLE CARDIAC DEVICE - An implantable cardiac device is configured and programmed to assess a patient's cardiopulmonary function by evaluating the patient's minute ventilation response. Such evaluation may be performed by computing a minute ventilation response slope, defined as the ratio of an incremental change in minute ventilation to an incremental change in measured activity level. The minute ventilation response slope may then be compared with a normal range to assess the patient's functional status. | 10-09-2008 |
20080255626 | IMPLANTABLE MEDICAL DEVICE CONFIGURED AS A PEDOMETER - This document discusses, among other things, a system including an implantable medical device. The implantable medical device includes a control circuit and a motion sensing device. The motion sensing device is coupled to the control circuit, and the motion sensing device is configured to transmit signals to the control circuit. The control circuit is configured to identify one or more steps of a patient using the motion sensing device signal. | 10-16-2008 |
20080275520 | Automatic modulation of pacing timing intervals using beat to beat measures - Methods and systems to modulate timing intervals for pacing therapy are described. For each cardiac cycle, one or both of an atrioventricular (A-V) timing interval and an atrial (A-A) timing interval are modulated to oppose beat-to-beat ventricular (V-V) timing variability. Pacing therapy is delivered using the modulated timing intervals. | 11-06-2008 |
20080281370 | APPARATUS AND METHOD FOR HEART FAILURE INDICATION BASED ON HEART RATE, ONSET AND TACHYARRHYTHMIA - An indication of an actual or potential heart failure condition is computed. One example includes monitoring a first heart rate preceding a first onset of a first sinus tachyarrhythmia episode. Upon detecting the first sinus tachyarrhythmia episode, the indication is automatically provided using information about the first heart rate and how quickly the first onset occurs. | 11-13-2008 |
20090054944 | Modulation of AV delay to control ventricular interval variability - System and methods provide pacing therapy that modulates the atrioventricular (AV) delay to control ventricular interval variability. A base AV delay is determined as a function of heart rate. For each cardiac cycle, the base AV delay is modulated to reduce beat-to-beat variability of successive ventricular beats. The modulated AV delay compensates for variability of successive atrial beats. For example, modulation of the base AV delay may involve varying the AV delay inversely with a change in atrial interval. | 02-26-2009 |
20090082823 | Variable shortening of AV delay for treatment of cardiac disease - An implantable pacing device for delivering ventricular pacing may be configured to intermittently and variably reduce the AV delay interval used in an atrial triggered pacing mode in a manner that simulates exercise. The device may be programmed to intermittently switch to and from a variably shortened AV delay mode according to defined entry and exit conditions. | 03-26-2009 |
20090118627 | SYSTEM AND METHOD FOR EVALUATING CARDIAC PERFORMANCE RELATIVE TO PERFORMANCE OF AN INTRATHORACIC PRESSURE MANEUVER - A system and method for evaluating cardiac performance relative to performance of an intrathoracic pressure maneuver is described. Blood pressure is indirectly sensed by directly collecting intracardiac impedance measures through an implantable medical device. Cardiac functional changes to the blood pressure are evaluated in response to performance of an intrathoracic pressure maneuver. | 05-07-2009 |
20090287270 | SELF-CALIBRATING RATE-ADAPTIVE PACEMAKER - A system and method for automatically adjusting the operating parameters of a rate-adaptive cardiac pacemaker. In accordance with the method, maximum exertion levels attained by the patient are measured at periodic intervals and stored. The stored maximum exertion levels may then be used to update a long-term maximal exertion level, and the slope of the rate-response curve is adjusted to map the updated long-term maximal exertion level to a maximum allowable pacing rate. The stored maximum exertion levels may also be used to update a sensor target rate which is used to adjust the slope of the rate response curve. | 11-19-2009 |
20090312815 | Systems and Methods for Improving Heart Rate Kinetics in Heart Failure Patients - Adaptive rate pacing for improving heart rate kinetics in heart failure patients involves determining onset and sustaining of patient activity. The patient's heart rate response to the sustained activity is evaluated during a time window defined between onset of the activity and a steady-state exercise level. If the patient's heart rate response to the sustained activity is determined to be slow, a pacing therapy is delivered at a rate greater than the patient's intrinsic heart rate based on a profile of the patient's heart rate response to varying workloads. If determined not to be slow, the pacing therapy is withheld. Monitoring-only configurations provide for acquisition and organization of physiological data for heart failure patients. These data can be acquired on a per-patient basis and used to assess the HF status of the patient. | 12-17-2009 |
20100137931 | Implantable Cardiac Device With Dyspnea Measurement - Cardiac monitoring and/or stimulation methods and systems employing dyspnea measurement. An implantable cardiac device may sense transthoracic impedance and determine a patient activity level. An index indicative of pulmonary function is implantably computed to detect an episode of dyspnea based on a change, trend, and/or value exceeding a threshold at a determined patient activity level. Trending one or more pulmonary function index values may be done to determine a patient's pulmonary function index profile, which may be used to adapt a cardiac therapy. A physician may be automatically alerted in response to a pulmonary function index value and/or a trend of the patient's pulmonary index being beyond a threshold. Computed pulmonary function index values and their associated patient's activity levels may be stored periodically in a memory and/or transmitted to a patient-external device. | 06-03-2010 |
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 |
20100305643 | VENTILATION SENSOR RATE RESPONSE NORMALIZATION AND CALCULATION - A cardiac rhythm management (CRM) device can extract ventilation information from thoracic impedance or other information, and adjust a delivery rate of the CRM therapy. A tidal volume of a patient is measured and used to adjust a ventilation rate response factor. The measured tidal volume can optionally be adjusted using a ventilation rate dependent adjustment factor. The ventilation rate response factor can also be adjusted using a maximum voluntary ventilation (MVV), an age predicted maximum heart rate, a resting heart rate, and a resting ventilation determined for the patient. In various examples, a global ventilation sensor rate response factor (for a population) can be programmed into the CRM device, and automatically tailored to be appropriate for a particular patient. | 12-02-2010 |
20110046520 | IMPLANTABLE MEDICAL DEVICE CONFIGURED AS A PEDOMETER - This document discusses, among other things, a system including an implantable medical device. The implantable medical device includes a control circuit and a motion sensing device. The motion sensing device is coupled to the control circuit, and the motion sensing device is configured to transmit signals to the control circuit. The control circuit is configured to identify one or more steps of a patient using the motion sensing device signal. | 02-24-2011 |
20110152963 | AUTOMATIC PROGRAMMING OF RATE-ADAPTIVE THERAPY VIA ACTIVITY MONITORING - A rate-adaptive pacemaker and a method for its operation in which the response factor for a minute ventilation sensor or other type of exertion level sensor is automatically set during a parameter adjustment mode that utilizes an activity level measurement to determine when the patient is at a target activity level with which is associated an appropriate target pacing rate. In a preferred embodiment, the target activity level corresponds to casual walking (e.g., 2 mph at a 4% grade) with a target pacing rate selected as appropriate for that level of activity in the individual patient. | 06-23-2011 |
20110160789 | Modulation of AV Delay to Control Ventricular Interval Variability - System and methods provide pacing therapy that modulates the atrioventricular (AV) delay to control ventricular interval variability. A base AV delay is determined as a function of heart rate. For each cardiac cycle, the base AV delay is modulated to reduce beat-to-beat variability of successive ventricular beats. The modulated AV delay compensates for variability of successive atrial beats. For example, modulation of the base AV delay may involve varying the AV delay inversely with a change in atrial interval. | 06-30-2011 |
20120004697 | NON-LINEAR DYNAMIC AV DELAY - A non-linear dynamic specified AV delay can be used, such as to help maintain cardiac resynchronization therapy, such as in patients with one or more symptoms of congestive heart failure. | 01-05-2012 |
20120004698 | PHYSIOLOGIC DEMAND DRIVEN PACING - Physiologic demand driven pacing can be used to maintain cardiac synchrony and improve hemodynamic function in patients with heart failure. | 01-05-2012 |
20120130440 | AUTOMATIC DETERMINATION OF CHRONOTROPIC INCOMPETENCE USING ATRIAL PACING AT REST - An apparatus comprises an implantable cardiac signal sensing circuit that provides an electrical cardiac signal representative of cardiac activity of a subject, an implantable therapy circuit that delivers electrical pacing stimulation energy to a heart of a subject, and a controller circuit. The controller circuit includes a chronotropic incompetence detection circuit that initiates pacing of an atrium of the subject at a rate higher than a device-indicated rate or a sensed intrinsic rate, monitor the AV interval, initiates an increase in the pacing rate while continuing the monitoring of the AV interval, calculates a change in AV intervals between a highest paced rate used in the monitoring and a lowest paced rate used in the monitoring, and indicates that the AV intervals are evidence of chronotropic incompetence when the calculated change in the AV intervals exceeds a specified threshold AV interval change value. | 05-24-2012 |
20120130443 | Automatic Adaptation of A-V Delay and HR for Heart Failure using Beat to Beat Measures - Methods and systems to modulate timing intervals for pacing therapy are described. For each cardiac cycle, one or both of an atrioventricular (A-V) timing interval and an atrial (A-A) timing interval are modulated to oppose beat-to-beat ventricular (V-V) timing variability. Pacing therapy is delivered using the modulated timing intervals. | 05-24-2012 |
20120143276 | CARDIOPULMONARY FUNCTIONAL STATUS ASSESSMENT VIA METABOLIC RESPONSE DETECTION BY IMPLANTABLE CARDIAC DEVICE - An implantable cardiac device is configured and programmed to assess a patient's cardiopulmonary function by evaluating the patient's minute ventilation response. Such evaluation may be performed by computing a minute ventilation response slope, defined as the ratio of an incremental change in minute ventilation to an incremental change in measured activity level. The minute ventilation response slope may then be compared with a normal range to assess the patient's functional status. | 06-07-2012 |
20120197323 | RESPIRATORY PARAMETERS FOR ARRHYTHMIA DETECTION AND THERAPY - An implantable or ambulatory medical device can include a cardiac signal sensing circuit configured to provide a sensed cardiac depolarization signal of a heart of a subject, a respiration sensing circuit configured to provide a signal representative of respiration of the subject, and a control circuit communicatively coupled to the cardiac signal sensing circuit and the respiration circuit. The control circuit includes a tachyarrhythmia detection circuit configured to determine heart rate using the depolarization signal, determine a respiration parameter of the subject using the respiration signal, calculate a ratio using the determined heart rate and the determined respiration parameter, generate an indication of tachyarrhythmia when the calculated ratio satisfies a specified detection ratio threshold value, and provide the indication of tachyarrhythmia to a user or process. | 08-02-2012 |
20130184776 | RATE ADAPTIVE CARDIAC PACING SYSTEMS AND METHODS - The invention relates to cardiac rhythm management systems, and more particularly, to rate adaptive cardiac pacing systems and methods. In an embodiment, the invention includes a cardiac rhythm management device. The device can include a pulse generator for generating electrical pulses to be delivered to a heart at a pacing rate, a processor in communication with the pulse generator, and one or more sensors for sensing pulmonary function and cardiac function. The processor can be configured to increase the pacing rate if the pulmonary function is increasing with time and the cardiac function is not decreasing with time, maintain the pacing rate if the pulmonary function is increasing with time and the cardiac function is decreasing with time, and decrease the pacing rate if the respiratory function is decreasing with time. | 07-18-2013 |
20130274821 | AUTOMATIC MODULATION OF PACING TIMING INTERVALS USING BEAT TO BEAT MEASURES - Methods and systems to modulate timing intervals for pacing therapy are described. For each cardiac cycle, one or both of an atrioventricular (A-V) timing interval and an atrial (A-A) timing interval are modulated to oppose beat-to-beat ventricular (V-V) timing variability. Pacing therapy is delivered using the modulated timing intervals. | 10-17-2013 |
20130331902 | IMPLANTABLE CARDIAC DEVICE WITH DYSPNEA MEASUREMENT - Cardiac monitoring and/or stimulation methods and systems employing dyspnea measurement. An implantable cardiac device may sense transthoracic impedance and determine a patient activity level. An index indicative of pulmonary function is implantably computed to detect an episode of dyspnea based on a change, trend, and/or value exceeding a threshold at a determined patient activity level. Trending one or more pulmonary function index values may be done to determine a patient's pulmonary function index profile, which may be used to adapt a cardiac therapy. A physician may be automatically alerted in response to a pulmonary function index value and/or a trend of the patient's pulmonary index being beyond a threshold. Computed pulmonary function index values and their associated patient's activity levels may be stored periodically in a memory and/or transmitted to a patient-external device. | 12-12-2013 |
20140012345 | CARDIOPULMONARY FUNCTIONAL STATUS ASSESSMENT VIA METABOLIC RESPONSE DETECTION BY IMPLANTABLE CARDIAC DEVICE - An implantable cardiac device is configured and programmed to assess a patient's cardiopulmonary function by evaluating the patient's minute ventilation response. Such evaluation may be performed by computing a minute ventilation response slope, defined as the ratio of an incremental change in minute ventilation to an incremental change in measured activity level. The minute ventilation response slope may then be compared with a normal range to assess the patient's functional status. | 01-09-2014 |
20140221853 | IMPLANTABLE CARDIAC DEVICE WITH DYSPNEA MEASUREMENT - Cardiac monitoring and/or stimulation methods and systems employing dyspnea measurement. An implantable cardiac device may sense transthoracic impedance and determine a patient activity level. An index indicative of pulmonary function is implantably computed to detect an episode of dyspnea based on a change, trend, and/or value exceeding a threshold at a determined patient activity level. Trending one or more pulmonary function index values may be done to determine a patient's pulmonary function index profile, which may be used to adapt a cardiac therapy. A physician may be automatically alerted in response to a pulmonary function index value and/or a trend of the patient's pulmonary index being beyond a threshold. Computed pulmonary function index values and their associated patient's activity levels may be stored periodically in a memory and/or transmitted to a patient-external device. | 08-07-2014 |