Patent application number | Description | Published |
20090276001 | METHOD OF CONTINUOUS CAPTURE VERIFICATION IN CARDIAC RESYNCHRONIZATION DEVICES - In bi-ventricular pacing devices (including CRT devices) analysis of myocardial electrogram signals in one ventricle (e.g., a left ventricle, or “LV”) can same ventricle, on a continuous (every pacing cycle), triggered, aperiodic and/or periodic basis. Rather than using an evoked-response principle as has been the basis of capture detection in prior art and other systems, a principle employed via the present invention uses evidence of inter-ventricular conduction (i.e., from the opposite chamber) and/or atrio-ventricular conduction as evidence of LOC, since a non-capturing pacing stimulus provided to a first chamber will allow the myocardial tissue of the first chamber to remain non-refractory and thus inter-ventricular and atrio-ventricular wavefront propagation and conduction can commence and be detected thereby revealing whether LOC has occurred. | 11-05-2009 |
20100087882 | VENTRICULAR EVENT FILTERING FOR AN IMPLANTABLE MEDICAL DEVICE - Pacing parameters are provided to address cross talk and intrinsic ventricular events occurring within a predefined blanking period following an atrial event. The parameters are used in conjunction with protocol for minimizing or reducing ventricular pacing, wherein ignoring intrinsic ventricular events during the blanking period might otherwise affect the performance of the protocol. | 04-08-2010 |
20100137935 | LV THRESHOLD MEASUREMENT AND CAPTURE MANAGEMENT - The invention provides methods and apparatus for determining in a non-tracking pacing mode (e.g., DDI/R, VVI/R) whether a ventricular pacing stimulus is capturing a paced ventricle, including some or all of the following aspects. For example, increasing a ventricular pacing rate a nominal amount to an overdrive pacing rate higher than a most recent heart rate and evaluating a conduction interval from a first pacing ventricle to a second sensing ventricle and then continuing to monitor the underlying rate to ensure that a threshold testing pacing rate will not exceed a predetermined minimum interval and providing pacing stimulation to the first ventricle and sensing the second ventricle to determine whether the pacing stimulation to the first ventricle was one of sub-threshold and supra-threshold. The methods and apparatus are especially useful in conjunction with ensuring actual delivery of a ventricular pacing regime (e.g., cardiac resynchronization therapy or “CRT”). | 06-03-2010 |
20100174334 | SYSTEM AND METHOD FOR PROVIDING IMPROVED ATRIAL PACING BASED ON PHYSIOLOGICAL NEED - An implantable medical device operates according to a ventricular pacing protocol (VPP) that precludes ventricular pacing in any cardiac cycle where a sensed ventricular event has occurred in the preceding cycle. Improved ventricular sensing, detection and classification is provided. | 07-08-2010 |
20100222834 | SYSTEM AND METHOD FOR CONDITIONAL BIVENTRICULAR PACING - An implantable pacing system with single, double and triple chamber pacing capabilities, provided individually or in concert on a conditional or continuous basis depending upon ongoing analyses of atrial rhythm status, atrioventricular conduction status and ventricular rate. A mode is selected to reduce the occurrence of any ventricular pacing in favor of intrinsic atrioventricular and ventricular conduction. If excessively long PR intervals are occurring too frequently or atrioventricular conduction is unreliable or absent, the implantable pulse generator is operated in a conditional triple chamber pacing mode that provides atrial-synchronous biventricular pacing in every cardiac cycle for a period of time as necessary to restore and maintain AV synchrony, while minimizing ventricular asynchrony otherwise associated with monochamber RV pacing as in conventional dual chamber pacing systems. Similarly, biventricular pacing is provided in every cardiac cycle when ventricular rates are undesirably slow during atrial fibrillation, where AV synchronization is excluded. | 09-02-2010 |
20100222837 | SYSTEM AND METHOD FOR CONDITIONAL BIVENTRICULAR PACING - An implantable pacing system with single, double and triple chamber pacing capabilities, provided individually or in concert on a conditional or continuous basis depending upon ongoing analyses of atrial rhythm status, atrioventricular conduction status and ventricular rate. A mode is selected to reduce the occurrence of any ventricular pacing in favor of intrinsic atrioventricular and ventricular conduction. If excessively long PR intervals are occurring too frequently or atrioventricular conduction is unreliable or absent, the implantable pulse generator is operated in a conditional triple chamber pacing mode that provides atrial-synchronous biventricular pacing in every cardiac cycle for a period of time as necessary to restore and maintain AV synchrony, while minimizing ventricular asynchrony otherwise associated with monochamber RV pacing as in conventional dual chamber pacing systems. Similarly, biventricular pacing is provided in every cardiac cycle when ventricular rates are undesirably slow during atrial fibrillation, where AV synchronization is excluded. | 09-02-2010 |
20100222838 | SYSTEM AND METHOD FOR CONDITIONAL BIVENTRICULAR PACING - An implantable pacing system with single, double and triple chamber pacing capabilities, provided individually or in concert on a conditional or continuous basis depending upon ongoing analyses of atrial rhythm status, atrioventricular conduction status and ventricular rate. A mode is selected to reduce the occurrence of any ventricular pacing in favor of intrinsic atrioventricular and ventricular conduction. If excessively long PR intervals are occurring too frequently or atrioventricular conduction is unreliable or absent, the implantable pulse generator is operated in a conditional triple chamber pacing mode that provides atrial-synchronous biventricular pacing in every cardiac cycle for a period of time as necessary to restore and maintain AV synchrony, while minimizing ventricular asynchrony otherwise associated with monochamber RV pacing as in conventional dual chamber pacing systems. Similarly, biventricular pacing is provided in every cardiac cycle when ventricular rates are undesirably slow during atrial fibrillation, where AV synchronization is excluded. | 09-02-2010 |
20110022104 | METHODS AND APPARATUS FOR DETECTING VENTRICULAR DEPOLARIZATIONS DURING ATRIAL PACING - AV synchronous, dual chamber pacing systems are disclosed having improved sensing of ectopic ventricular depolarizations or PVCs coincidentally occurring at or shortly following delivery of an A-PACE pulse. A first ventricular sense amplifier that is blanked during and following delivery of an A-PACE pulse is coupled to active and indifferent ventricular pace/sense electrodes defining a ventricular sense vector for sensing natural ventricular depolarizations and declaring a V-EVENT. A far field PVC sense amplifier coupled to a far field PVC sense electrode pair defining a PVC sense vector detects such PVCs while the ventricular sense amplifier is blanked. A PVC declared during the ventricular blanking period by the far field PVC sense amplifier is employed to deliver a VSP pulse upon time-out of a VSP delay, if the VSP function is provided and programmed ON, and/or to halt time-out of an AV delay. | 01-27-2011 |
20110029034 | ALGORITHM TO MODULATE ATRIAL-VENTRICULAR DELAY AND RATE RESPONSE BASED ON AUTONOMIC FUNCTION - An implantable medical device and associated method provide atrial pacing and measure an atrial ventricular (AV) delay. An autonomic function index is computed using the AV delay. The autonomic function index may be compiled in a medical report. In some embodiments, the autonomic function index is used to adjust atrial pacing control parameters. | 02-03-2011 |
20110040346 | METHOD FOR SCHEDULING ATRIAL-VENTRICULAR CONDUCTION CHECKS IN MINIMUM VENTRICULAR PACING - A medical device and associated method deliver cardiac pacing in a dual chamber pacing mode and schedule an atrial-ventricular (AV) conduction check during the dual chamber pacing mode to detect the presence of AV conduction. If AV conduction is detected during the scheduled AV conduction check, the medical device switches to an atrial pacing mode and switches back to the dual chamber pacing mode in response to an absence of AV conduction during the atrial pacing mode. The detected AV conduction is identified as a false positive detection in response to the pacing mode switch to the dual chamber pacing mode occurring within a predetermined interval of time from detecting the AV conduction. | 02-17-2011 |
20110106196 | IDENTIFICATION AND TREATMENT OF JUNCTIONAL RHYTHMS - An implantable medical device and associated method provide atrial pacing and measure intervals between atrial pacing pulses and subsequently sensed ventricular events. A decreasing trend in the of intervals indicative of a pre-junctional rhythm is detected. The atrial pacing pulse is delivered at a shortened atrial pacing pulse interval in response to detecting the decreasing trend to reduce the likelihood of a junctional rhythm. | 05-05-2011 |
20110112596 | SYSTEM AND METHOD FOR DETERMINING INTRINSIC AV INTERVAL TIMING - An atrial based pacing protocol promotes intrinsic conduction. An entire cardiac cycle is monitored for ventricular activity and permitted to lapse with ventricular activity. Ventricular pacing is available in a cardiac cycle immediately subsequent to such a skipped beat. When monitoring for intrinsic ventricular events, an event is expected within a given window. If no such event is detected, the cardiac cycle is truncated, leading to a shorter cycle that is devoid of ventricular activity. The subsequent cycle has a high likelihood of a ventricular sensed event and a greater than normal AV interval is provided prior to pacing. | 05-12-2011 |
20110152660 | METHODS AND APPARATUS FOR AUTOMATICALLY TRACKING HEART FAILURE STATUS - Assessing symptomatic and asymptomatic physiologic changes due to chronic heart failure involves apparatus and methods for gauging degradation and possible improvement using automated measurement of inter-ventricular conduction time, both alone and in combination with other automated physiologic tests. Conduction times increase due to the greater distance a wavefront must traverse as a heart enlarges. Analysis of conduction time can be used to verify the occurrence of cardiac remodeling due to heart failure as well as beneficial reverse remodeling due to successful heart failure therapy delivery. Patient activity level(s) and presence/increase in pulmonary fluids can also be used to automatically determine changes in heart failure status and/or predict hospitalization. Conduction time is monitored between electrodes positioned in the left and right ventricles of the heart via endocardial or epicardial electrodes. | 06-23-2011 |
20110160791 | CONFIGURING OPERATING PARAMETERS OF A MEDICAL DEVICE BASED ON EXPOSURE TO A DISRUPTIVE ENERGY FIELD - An implantable medical device (IMD) determines an effect of the disruptive energy field and adjusts one or more operating parameters of the IMD based on at least the determined effect. In some instances, the IMD may determine an actual effect of the disruptive energy field, such as a temperature change, impedance change, pacing or sensing threshold change, MRI-induced interference one pacing or sensing, or other actual effect. In other instances, the IMD may determine a predicted effect of the disruptive energy field based on one or more characteristics of the exposure. In any case, the IMD adjusts one or more parameters based on at least the determined effect. | 06-30-2011 |
20120101543 | CAPTURE THRESHOLD MEASUREMENT FOR SELECTION OF PACING VECTOR - Various techniques for selecting a pacing vector based on pacing capture thresholds are described. One example method described includes for each of a plurality of vectors, iteratively delivering at least one pacing stimulus at each of a plurality of magnitudes within a predetermined range of magnitudes to a first chamber, determining if a depolarization occurred in a second chamber of the heart within a predetermined threshold time interval after the pacing stimulus that is less than an interval, identifying a pacing stimulus for which a depolarization in the second chamber does not occur within the predetermined threshold time interval, determining a capture threshold magnitude for the vector based on the magnitude of the pacing pulse for which a depolarization in the second chamber does not occur within the predetermined threshold time interval, and recording the capture threshold magnitudes. | 04-26-2012 |
20120101546 | METHOD AND APPARATUS TO DETERMINE THE RELATIVE ENERGY EXPENDITURE FOR A PLURALITY OF PACING VECTORS - A medical device system determines and displays relative energy expenditure information for programmable parameter values. The system establishes a programmable parameter and multiple values of the parameter to be compared. A module performs a measurements for each of the multiple values and related to energy expenditure of a battery of an implantable medical device when operating according to each of the multiple parameter values. An energy expenditure for each of the values is computed using the measurements, and a graphical user interface is generated for displaying information corresponding to the computed energy expenditure for multiple parameter values. | 04-26-2012 |
20120109235 | CAPTURE DETECTION IN RESPONSE TO LEAD RELATED CONDITIONS - Various techniques for detecting cardiac capture in response to a detected lead related condition are described. One example method described includes delivering a pacing therapy to a heart of a patient, periodically determining whether the pacing therapy captures the heart of the patient, detecting a lead related condition, and, in response to the detected lead related condition, increasing a frequency of determining whether the pacing therapy captures the heart. | 05-03-2012 |
20130030491 | METHOD FOR DISCRIMINATING ANODAL AND CATHODAL CAPTURE - An implantable device and associated method discriminate between cathodal and anodal capture during electrical stimulation. A control response to a pacing pulse delivered using a candidate cathode electrode and a universal anode and responses to bipolar pacing pulses delivered using candidate bipoles including the candidate cathode are measured. Responsive to the control response meeting a threshold response, the control response is classified as normal and each of the responses for the candidate bipoles are compared to the control response. The responses for the candidate bipoles are each classified based on the comparison. | 01-31-2013 |
20130030492 | METHOD FOR DISCRIMINATING ANODAL AND CATHODAL CAPTURE - An implantable device and associated method detect anodal capture during electrical stimulation. A first pacing pulse is delivered using a first cathode and a first anode. A second pacing pulse is delivered using the first cathode and a second anode. A first response to the first pacing pulse and a second response to the second pacing pulse are measured. Anodal capture of the first pacing pulse at the first anode is detected in response to a first difference between the first response and the second response. | 01-31-2013 |
20130030493 | METHODS FOR SETTING CARDIAC PACING PARAMETERS IN RELATIVELY HIGH EFFICIENCY PACING SYSTEMS - According to some methods, for example, preprogrammed in a microprocessor element of an implantable cardiac pacing system, at least one of a number of periodic pacing threshold searches includes steps to reduce an evoked response amplitude threshold for evoked response signal detection. The reduction may be to a minimum value measurable above zero, for example, as determined by establishing a ‘noise floor’. Alternately, amplitudes of test pacing pulses and corresponding post pulse signals are collected and reviewed to search for a break, to determine a lower value to which the evoked response threshold may be adjusted without detecting noise. Subsequent to reducing the threshold, if no evoked response signal is detected for a test pulse applied at or above a predetermined maximum desirable pulse energy, an operational pacing pulse energy is set to greater than or equal to the maximum desirable in conjunction with a reduction in pacing rate. | 01-31-2013 |
20130079861 | IMD STABILITY MONITOR - Techniques for determining an attachment stability of leadless pacing device (LPD) implanted within a patient are described. For example, the LPD may detect one or more stability metrics from one or more electrodes of the LPD and/or an activity sensor within the LPD. Based on one or more of these stability metrics, e.g., a mechanical motion of the LPD, a stability module within the LPD may determine the attachment stability of the LPD within the patient. If the attachment stability is insufficient to provide efficacious therapy or indicates at least partial dislodgement of the LPD from tissue, the LPD may wirelessly transmit stability information to an external device. In some examples, the LPD may be implanted within a chamber of the heart. | 03-28-2013 |
20130131748 | METHOD FOR EFFICIENT DELIVERY OF DUAL SITE PACING - An implantable device and associated method for delivering a multi-site pacing therapy includes electrodes for sensing cardiac signals and delivering cardiac pacing pulses to a first pacing site along a heart chamber and a therapy delivery module for delivering cardiac pacing pulses to a patient's heart via the electrodes. A sensing module measures an activation time at multiple pacing electrode sites along the heart chamber in response to delivering pacing pulses at the first pacing site. A controller is configured to identify a second pacing site from the plurality of pacing electrode sites in response to the activation times measured during pacing at the first site. | 05-23-2013 |
20130131749 | METHOD FOR EFFICIENT DELIVERY OF DUAL SITE PACING - An implantable device and associated method for delivering a multi-site pacing therapy includes electrodes for sensing cardiac signals and delivering cardiac pacing pulses. Electrodes positioned at first and second selected pacing sites are used to deliver pacing pulses to a first heart chamber using a bipole comprising the first electrode and the second electrode. A controller is configured to determine if anodal and cathodal capture can be achieved during pacing using the bipole. Responsive to anodal and cathodal capture being achieved, the controller selects a multi-site pacing configuration comprising the bipole for singly pacing the first and second pacing sites | 05-23-2013 |
20130197599 | ADAPTIVE CARDIAC RESYNCHRONIZATION THERAPY - Cardiac resynchronization therapy (CRT) delivered to a heart of a patient may be adjusted based on detection of a surrogate indication of the intrinsic atrioventricular conduction of the heart. In some examples, the surrogate indication is determined to be a sense event of the first depolarizing ventricle of the heart within a predetermined period of time following the delivery of a fusion pacing stimulus to the later depolarizing ventricle. In some examples, the CRT is switched from a fusion pacing configuration to a biventricular pacing configuration if the surrogate indication is not detected, and the CRT is maintained in a fusion pacing configuration if the surrogate indication is detected. | 08-01-2013 |
20140121719 | LEADLESS PACEMAKER SYSTEM - A device includes a signal generator module, a processing module, and a housing. The signal generator module is configured to deliver pacing pulses to an atrium. The processing module is configured to detect a ventricular activation event and determine a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event. The processing module is further configured to schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval and control the signal generator module to deliver the pacing pulse at the scheduled time. The housing is configured for implantation within the atrium. The housing encloses the stimulation generator and the processing module. | 05-01-2014 |
20140121720 | LEADLESS PACEMAKER SYSTEM - A device includes a signal generator module, a processing module, and a housing. The signal generator module is configured to deliver pacing pulses to an atrium. The processing module is configured to detect a ventricular activation event and determine a length of an interval between the ventricular activation event and a previous atrial event that preceded the ventricular activation event. The processing module is further configured to schedule a time at which to deliver a pacing pulse to the atrium based on the length of the interval and control the signal generator module to deliver the pacing pulse at the scheduled time. The housing is configured for implantation within the atrium. The housing encloses the stimulation generator and the processing module. | 05-01-2014 |
20140121722 | METHODS FOR SETTING CARDIAC PACING PARAMETERS IN RELATIVELY HIGH EFFICIENCY PACING SYSTEMS - According to some methods, for example, preprogrammed in a microprocessor element of an implantable cardiac pacing system, at least one of a number of periodic pacing threshold searches includes steps to reduce an evoked response amplitude threshold for evoked response signal detection. The reduction may be to a minimum value measurable above zero, for example, as determined by establishing a ‘noise floor’. Alternately, amplitudes of test pacing pulses and corresponding post pulse signals are collected and reviewed to search for a break, to determine a lower value to which the evoked response threshold may be adjusted without detecting noise. Subsequent to reducing the threshold, if no evoked response signal is detected for a test pulse applied at or above a predetermined maximum desirable pulse energy, an operational pacing pulse energy is set to greater than or equal to the maximum desirable in conjunction with a reduction in pacing rate. | 05-01-2014 |
20140135867 | CAPTURE THRESHOLD MEASUREMENT FOR SELECTION OF PACING VECTOR - Various techniques for facilitating selection of a pacing vector for pacing a chamber of a heart are described. One example method described includes, for each of a plurality of vectors, delivering a pacing pulse to capture a first heart chamber, determining a first time interval between the pacing pulse and a sensed event in a second heart chamber, determining a capture detection window in response to the determined first time interval, and enabling a capture detection module to iteratively decrease a pacing pulse magnitude delivered in the first heart chamber until an event in the second heart chamber is not sensed during the determined capture detection window. | 05-15-2014 |