Abstract: An implantable cardioverter defibrillator includes a communication interface operable to receive a communication signal from an external programmer. The communication signal includes a command to switch the ICD from a first mode to a second mode. A processor is in electrical communication with the communication interface and configured to switch the ICD between the first and second modes. A battery is configured to supply low DC voltage. A converter is configured to convert the low DC voltage to a high DC voltage. An energy storage capacitor is electrically coupled to the converter and configured to store a therapeutic energy or high DC voltage including at least 15 joules. The second mode includes activating the converter to convert the low DC voltage to the high DC voltage and storing the therapeutic energy or at least 15 joules within the energy storage capacitor during a period of time of the second mode.

Abstract: A non-invasive bodily-attached ambulatory medical monitoring and treatment device with pacing is provided. The noninvasive ambulatory pacing device includes a battery, at least one therapy electrode coupled to the battery, a memory storing information indicative of a patient's cardiac activity, and at least one processor coupled to the memory and the at least one therapy electrode. The at least one processor is configured to identify a cardiac arrhythmia within the information and execute at least one pacing routine to treat the identified cardiac arrhythmia.

Abstract: Devices, systems, and methods for treating a heart of a patient may make use of structures which limit a size of a chamber of the heart, such as by deploying a tensile member to bring a wall of the heart toward (optionally into contact with) a septum of the heart. The implant may include an electrode or other structure for applying pacing signals to one or both ventricles of the heart, for defibrillating the heart, for sensing beating of the heart or the like. A wireless telemetry and control system may allowing the implant to treat congestive heart failure, monitor the results of the treatment, and apply appropriate electrical stimulation.

Abstract: A system and method of enabling detection enhancements selected from a plurality of detection enhancements. In a system having a plurality of clinical rhythms, including a first clinical rhythm, where each of the detection enhancements is associated with the clinical rhythms, the first clinical rhythm is selected. The first clinical rhythm is associated with first and second detection enhancements. When the first clinical rhythm is selected, parameters of the first and second detection enhancements are set automatically. A determination is made as to whether changes are to be made to the parameters. If so, one or more of the parameters are modified under user control.

Abstract: A method discriminates between ventricular arrhythmia and supraventricular arrhythmia by determining the direction of an electrical signal conducted through the atrioventricular node. An implantable cardiac defibrillator provides atrioventricular and ventriculoatrial pacing bursts to determine if an arrhythmia with a 1:1 atrial to ventricular relationship is due to ventricular tachycardia or supraventricular tachycardia. This discrimination capability reduces the incidence of inappropriate shocks from dual-chamber implantable cardiac defibrillators to near zero and provides a method to differentially diagnose supraventricular tachycardia from ventricular tachycardia.

Abstract: A defibrillator is disclosed for communication with a transmitter associated with a location. The defibrillator is configured to generate an electronic signature for determining a position of the defibrillator within the location. The electronic signature includes electronic data correlating the position of the defibrillator to the transmitter. The electronic data may include GPS data. The defibrillator is configured to generate the electronic signature during a first and a second window of time to define a first and a second electronic signature. A differential between the first and the second electronic signatures corresponds to a positional state of the defibrillator, indicating movement within or between two locations. In a disclosed system, the first electronic signature is stored in a database and a server is configured to generate the differential and to communicate the positional state of the defibrillator to a stakeholder. Methods of use are also disclosed.

Abstract: An apparatus for determining heart transplant rejection of a heart in a patient includes at least two electrodes adapted to be sewn into the heart that span the left ventricle. The apparatus includes a voltage generator adapted to be inserted in the patient which generates a voltage to the two electrodes and senses the resulting voltage from the two electrodes. A method for determining heart transplant rejection of a heart in a patient. A pacemaker for a patient (including bi-ventricular pacing and AICDs). The pacemaker includes an RV lead having four electrodes adapted to be inserted into the RV apex. The pacemaker includes a voltage generator which generates a voltage signal to the electrodes and senses the instantaneous voltage along the length of the RV and determines the real and imaginary components to remove the myocardial components of the septum and RV free wall to determine absolute RV blood volume. The pacemaker includes a battery connected to the voltage generator.

Abstract: Medical devices are described for performing mapping, ablating, pacing, and/or defibrillating procedures on one or more layers of the cardiac wall via an epicardial or extra-pericardial approach in a minimally invasive (e.g., orthoscopic) surgical procedure. One of the medical devices described includes a main support member and one or more secondary support members extending outwardly from the main support member having electrodes configured to receive electrical impulses. The secondary support member may include a support pad configured to be removably attached to a corresponding area of the epicardium for holding the medical device in place during a procedure, such as through application of vacuum pressure via a containment dome provided on each secondary support member. Further, an ablating electrode may be slidably disposed along the main support member for transmitting energy to a target site proximate the electrode. Other devices and associated methods are also described.

Abstract: An implantable medical device such as an implantable pulse generator that includes EEG sensing for monitoring and treating neurological conditions, and leadless ECG sensing for monitoring cardiac signals. The device includes a connector block with provisions for cardiac leads which may be used/enabled when needed. If significant co-morbid cardiac events are observed in patients via the leadless ECG monitoring, then cardiac leads may be subsequently connected for therapeutic use.

Abstract: A wearable therapeutic device that includes a garment configured to contain an external defibrillator. The garment is configured to house at least one of an alarm module and a monitor and to house a first therapy electrode and a second therapy electrode. The garment is also configured to releasably receive a receptacle that contains a conductive fluid proximate to at least one of the first therapy electrode and the second therapy electrode, and to electrically couple the receptacle with the garment.

Abstract: Embodiments are directed to a medical device, such as a defibrillator, for use with an accessory capable of collecting a parameter of a patient. The medical device is capable of at least performing a basic functionality, an advanced functionality, and of defibrillating the patient. The medical device includes an energy storage module within a housing for storing an electrical charge that is to be delivered to the patient for the defibrillating. The medical device includes a processor structured to determine whether a data set received from the accessory confirms or not a preset authentication criterion about the accessory. Although when the accessory is coupled to the housing the medical device is capable of the defibrillating and the basic functionality, the medical device is capable of the advanced functionality only when the accessory is coupled to the housing and it is determined that the preset authentication criterion is confirmed. Embodiments also include methods of operation and a programmed solution.

Abstract: An implantable cardioverter-defibrillator system that includes at least one or more stimulation units, one or more detection units, one or more control units, two or more electrode poles and one or more high voltage capacitors. The at least one control unit is connected with the at least one stimulation unit, and the at least one control unit is connected with at the least one detection unit. The two or more electrode poles are in contact with body tissue, and the one or more high voltage capacitors are charged by at least one charging unit, wherein the at least one charging unit is connected to the at least one control unit.

Abstract: This document discusses, among other things, a modular antitachyarrhythmia therapy system. In an example, a modular antitachyarrhythmia system includes at least two separate modules that coordinate delivery an antitachyarrhythmia therapy, such as defibrillation therapy. In another example, a modular antitachyarrhythmia therapy system includes a sensing module, an analysis module, and a therapy module.

Abstract: Various embodiments provide a method for processing a stimulation signal. The method may include monitoring an output voltage on an electrode, the electrode being provided with the stimulation signal; determining whether the output voltage is lower than a threshold voltage; if it is determined that the output voltage is lower than the threshold voltage, modifying the waveform of the stimulation signal; and providing the modified stimulation signal to an object via the electrode.

Abstract: An electrode structure for use with a monitoring system. A thin flexible body of an electrode material comprising conductive rubber is provided with projections extending externally to a working surface. According to this construction of the working surface of the electrode only the projections make a contact to the recipient's skin. When the projections are provided with a small cross-section, the constant electrode-skin contact is ensured due to the resiliency of the electrode material.

Abstract: High frequency cardiac arrhythmias and fibrillations are terminated by electric field pacing pulses having an order of magnitude less energy than a conventional cardioversion or defibrillation energy. The frequency and number of the pulses are selected based on a frequency analysis of a present high frequency cardiac arrhythmia or fibrillation. The energy of the pulses is selected from 1/400 to ½ of the conventional defibrillation energy, and the amplitude of the electric field pacing pulses are selected such as to activate a multitude of effective pacing sites in the heart tissue per each pacing electrode. The number and locations of the effective pacing sites in the heart tissue are regulated by the amplitude of the electric field pacing pulses, and by an orientation of the electric field of the pulses.

Abstract: An implantable medical device may include a telemetry module, a sensing module, a therapy delivery module, and a processor. The processor may be configured to detect a patient event based on data generated by the sensing module, operate the IMD in a first mode in which the telemetry module is disabled and the therapy delivery module is at least partially disabled when the patient event is not detected, and operate the IMD in a second mode in which the telemetry module is enabled and the therapy delivery module is at least partially disabled when the patient event is detected. In some examples, the processor is configured to, in the second mode, generate a notification of the cardiac arrhythmia and transmit the notification to an external device via the telemetry module. The external device may reside inside an MRI room or outside the MRI room, and may communicate with other devices.

Abstract: A non-invasive bodily-attached ambulatory medical monitoring and treatment device with pacing is provided. The noninvasive ambulatory pacing device includes a battery, at least one therapy electrode coupled to the battery, a memory storing information indicative of a patient's cardiac activity, and at least one processor coupled to the memory and the at least one therapy electrode. The at least one processor is configured to identify a cardiac arrhythmia within the information and execute at least one pacing routine to treat the identified cardiac arrhythmia.

Abstract: A method of analysis of medical signals is presented which provides useful clinical information concerning the state of the myocardium during cardiopulmonary resuscitation (CPR). The analysis during CPR can be used to (i) identify the underlying rhythm, (ii) provide a measure of the efficacy of CPR, and (iii) to predict the outcome from a defibrillation shock.

Abstract: A method and system are provided to analyze valve related timing and monitor heart failure. The method and system comprise collecting cardiac signals associated with an atrial chamber of interest; collecting dynamic impedance (DI) data along an atria-function focused (AFF) vector to form a DI data set, the DI data set including information corresponding to a mechanical function (MF) of a valve associated with the atrial chamber of interest; identifying, from the cardiac signals, an intra-atrial conduction timing (IACT) associated with the atrial chamber of interest; estimating an MF landmark at which the mechanical function of the valve occurs based on the DI data set; analyzing a timing delay between the MF landmark and the IACT; and adjusting a therapy, based on the timing delay, to encourage atrial contribution to ventricular filling.

Abstract: A medical device and method for detecting and classifying cardiac rhythm episodes that includes a sensing module to sense cardiac events, a therapy delivery module, and a detection module configured to determine intervals between the sensed cardiac events, determine a predetermined cardiac episode is occurring in response to the determined intervals, determine whether a ventricular rate is greater than an atrial rate in response to the determined intervals, determine whether undersensing is occurring in response to the ventricular rate being greater than the atrial rate, perform a supraventricular tachycardia (SVT) discrimination analysis in response to undersensing occurring, and control the therapy delivery module to deliver therapy in response to the SVT discrimination analysis.

Abstract: A method of modifying the force of contraction of at least a portion of a heart chamber, including providing a subject having a heart, comprising at least a portion having an activation, and applying a non-excitatory electric field having a given duration, at a delay after the activation, to the portion, which causes the force of contraction to be increased by a least 5%.

Abstract: For terminating a high frequency arrhythmic electric state of a heart an electric signal representative of the present electric state of the heart is obtained. From the electric signal a dominant frequency of the present electric state is determined, and from the dominant frequency it is determined whether the present electric state of the heart is a high frequency arrhythmic electric state displaying at least one rotating wave. Further, a dominance level indicative of how dominant the dominant frequency is in the high frequency arrhythmic electric state is determined from the electric signal. Depending on the at least one dominant frequency, at least one series of electric pulses at intervals is generated. The electric pulses are applied to the heart starting at a point in time at which the dominance level exceeds a predefined threshold value for the heart being in a determined high frequency arrhythmic electric state.

Abstract: A peelable lid system includes a peelable lid, a seal configured to seal the peelable lid to a container, a handle coupled to the peelable lid, and a lifting mechanism coupled to handle. The lifting mechanism can be coupled to the peelable lid at a plurality of attachment points, including at least one attachment point coupled to the peelable lid away from the handle. The lifting mechanism can be configured to lift at least one portion of the peelable lid near each of the plurality of attachment points.

Abstract: A system including a sensor interface coupled to a processor. The sensor interface is configured to receive and process an analog electrocardiogram signal of a subject and provide a digitized electrocardiogram signal sampled over a first time period and a second time period that is subsequent to the first time period. The processor is configured to receive the digitized electrocardiogram signal, to analyze a frequency domain transform of the digitized electrocardiogram signal sampled over the first and second time periods and determine first and second metrics indicative of metabolic state of a myocardium of the subject during the first and second time periods, respectively, to compare the first and second metrics to determine whether the metabolic state of the myocardium of the subject is improving, and to indicate administration of an intervention to the subject in response to a determination that the metabolic state is not improving.

Abstract: An implantable heart therapy device connected to at least one right-ventricular electrode and one left-ventricular electrode that sense and stimulate the heart. The at least one right-ventricular and left-ventricular electrodes are each connected to a tachycardia identification unit, wherein the identification unit identifies ventricular tachycardias, and simultaneously evaluates the heart rate at the right-ventricular and at the left-ventricular electrodes. The implantable heart therapy device includes a right-ventricular stimulation unit that delivers antitachycardia stimulation to the right-ventricular electrode, a left-ventricular stimulation unit that delivers antitachycardia stimulation to the left-ventricular electrode, and a therapy control unit that assigns the stimulation location for the antitachycardia stimulation to the slower ventricle side if a dissimilar tachycardia is present.

Abstract: A single-pass pacing lead capable of sensing and pacing both the atria and the ventricles is described. In some examples, the single-pass pacing lead is connected to a DDD pacemaker. In some examples, the single-pass pacing lead comprises four electrodes. In some examples, the lead includes three electrodes configured to be positioned in or near an atrium, e.g., the right atrium, and one electrode configured to be positioned in or near a ventricle, e.g., the left ventricle, when the lead is implanted. In other examples, the lead includes two electrodes configured to be positioned in each of the atrium and ventricle when the lead is implanted. In some examples, one of the electrodes, which is configured to be positioned proximate the coronary sinus ostium when the lead is implanted, comprises a helical element for fixation of the lead to tissue.

Abstract: Devices and methods for providing pacing in multiple modes are provided. One device operates in a dual chamber (DDD or biventricular) mode and in a pacing mode favoring the spontaneous atrioventricular conduction such as an AAI mode (10) with a ventricular sensing or a mode with hysteresis of the atrioventricular delay. The device controls (10-18) the conditional switching from one mode to the other. The device comprises a hemodynamic sensor, including an endocardial acceleration sensor, derives a hemodynamic index representative of the hemodynamic tolerance of the patient to the spontaneous atrioventricular conduction. The device controls inhibiting or (20) forcing the conditional switching of the device to the DDD (or biventricular) mode according to the evolution of the hemodynamic index.

Abstract: A method for extinguishing a cardiac arrhythmia utilizes destructive interference of the passing of the reentry wave tip of an anatomical reentry through a depolarized region created by a relatively low voltage electric field in such a way as to effectively unpin the anatomical reentry. Preferably, the relatively low voltage electric field is defined by at least one unpinning shock(s) that are lower than an expected lower limit of vulnerability as established, for example, by a defibrillation threshold test. By understanding the physics of the electric field distribution between cardiac cells, the method permits the delivery of an electric field sufficient to unpin the core of the anatomical reentry, whether the precise or estimated location of the reentry is known or unknown and without the risk of inducting ventricular fibrillation. A number of embodiments for performing the method are disclosed.

Abstract: A medical device and method for detecting and classifying cardiac rhythm episodes that includes a sensing module to sense cardiac events; a therapy delivery module, and a detection module configured to determine intervals between the sensed cardiac events, determine a predetermined cardiac episode is occurring in response to the determined intervals, determine whether a ventricular rate is greater than an atrial rate in response to the determined intervals, determine whether oversensing is occurring in response to the ventricular rate being greater than the atrial rate, adjust the determined intervals in response to oversensing occurring to generate an adjusted ventricular rate, determine whether the cardiac episode is occurring in response to the adjusted ventricular rate, perform a supraventricular tachycardia (SVT) discrimination analysis in response to the cardiac episode occurring in response to the adjusted ventricular rate, and control the therapy delivery module to deliver therapy in response to the S

Abstract: Various aspects of the present subject matter provide devices and methods to treat AV-conducted ventricular tachyarrhythmia (AVCVT). According to various embodiments of the method, an AVCVT is sensed, an IVC-LA fat pad is stimulated when the AVCVT is sensed to block AV conduction, and bradycardia support pacing is provided while the IVC-LA fat pad is stimulated. Other aspects and embodiments are provided herein.

Abstract: A medical device can include a housing, an energy storage module within the housing to store an electrical charge, and a defibrillation port to guide via electrodes the stored electrical charge to a person in need of medical assistance. The medical device can also include a processor to perform a patient signal analysis on an electrocardiogram (ECG) signal corresponding to the person and further determine, based on a result of the patient signal analysis, whether post-shock transcutaneous pacing should be performed on the person.

Abstract: This document discusses, among other things, a modular antitachyarrhythmia therapy system. In an example, a modular antitachyarrhythmia system includes at least two separate modules that coordinate delivery an antitachyarrhythmia therapy, such as a defibrillation therapy. In another example, a modular antitachyarrhythmia therapy system includes a sensing module, an analysis module, and a therapy module.

Abstract: In various method embodiments for classifying an arrhythmia, a characteristic of a ventricle is sensed before delivering a diagnostic neural stimulation. The diagnostic neural stimulation is delivered, and the characteristic of the ventricle is sensed while delivering the diagnostic neural stimulation. The sensed characteristic of the ventricle before and during the diagnostic neural stimulation is used to classify the arrhythmia as either a supraventricular tachyarrhythmia (SVT) or a ventricular tachycardia (VT). According to various embodiments, the characteristic of the ventricle is ventricular rate, similarity values of sensed ventricular morphology to a normal sinus rhythm (NSR), or ventricular hemodynamics. Various embodiments use ventricular rate regularity before and during the diagnostic neural stimulation to classify an SVT as atrial fibrillation (AF) or as another SVT.

Abstract: A method of treating a patient in cardiac arrest (e.g., in fibrillation, electrochemical dissociation, or asystole), the method comprising delivering an agent for enhancement of cardiac function to the coronary arteries of the patient; and microperfusing the patient's cardiac tissue by electromagnetically stimulating the cardiac issue at an energy level below a threshold sufficient to defibrillate the heart.

Abstract: Defibrillators, software and methods are provided, for transmitting inaudible audio information to one or more external personal sound devices. The audio information may encode an audible indication, which can thus be played by an external personal sound device to a user such as a rescuer.

Abstract: The invention relates to an implantable ventricular heart stimulator (10), comprising an at least partially electrically conductive housing (12), an electrode line terminal for connection of a ventricular defibrillation electrode line (20) and a terminal for a defibrillation electrode (26). According to the invention, the heart stimulator has a far-field electrocardiogram detection unit (70) which has a first input connected to the terminal for the ventricular defibrillation electrode and has a second input connected to the electrically conductive housing and designed or configured to generate a far-field electrocardiogram on the basis of the electric potentials applied to the two inputs during operation.

Abstract: Implantable cardiac systems and methods for providing substernal pacing in an ICD system are described. In one example, an implantable cardiac system comprises an ICD system and an implantable leadless pacing device (LPD) communicatively coupled to the ICD system. The ICD system includes an ICD and an implantable defibrillation lead having a proximal portion coupled to the ICD and a distal portion having a defibrillation electrode configured to deliver a defibrillation shock to a heart of the patient. The LPD includes a housing, a first electrode on the housing, a second electrode on the housing, and a pulse generator within the housing and electrically coupled to the first electrode and the second electrode. The housing of the LPD is implanted substantially within an anterior mediastinum of the patient and the pulse generator is configured to deliver pacing pulses to a heart via the first and second electrodes.

Abstract: An implantable cardiac defibrillator (ICD) system includes an ICD implanted subcutaneously in a patient, a defibrillation lead having a proximal portion coupled to the ICD and a distal portion having a defibrillation electrode configured to deliver a defibrillation or cardioversion shock to a heart of the patient, and a pacing lead that includes a distal portion having one or more electrodes and a proximal portion coupled to the ICD. The distal portion of the pacing lead is implanted at least partially along a posterior side of a sternum of the patient within the anterior mediastinum. The ICD is configured to provide pacing pulses to the heart of the patient via the pacing lead and provide defibrillation shocks to the patient via the defibrillation lead. As such, the implantable cardiac system provides pacing from the substernal space for an extravascular ICD system.

Abstract: Techniques and methods for determining the number and type of leads that are connected to an implantable medical device (IMD) system are disclosed. The IMD system is configured having at least two modes of operation, the modes of operation corresponding to the number and type of leads that are coupled to the IMD system. In accordance with aspects of the disclosure, one of the at least two modes may be selected based on the determination of the number and type of leads that are connected to the IMD system.

Abstract: Substernal implantable cardioveter-defibrillator (ICD) systems and methods for providing substernal electrical stimulation therapy to treat malignant tachyarrhythmia, e.g., ventricular tachycardia (VT) and ventricular fibrillation (VF) are described. In one example, an implantable cardioveter-defibrillator (ICD) system includes an ICD implanted in a patient and an implantable medical electrical lead. The lead includes an elongated lead body having a proximal end and a distal portion, a connector at the proximal end of the lead body configured to couple to the ICD, and one or more electrodes along the distal portion of the elongated lead body. The distal portion of the elongated lead body of the lead is implanted substantially within an anterior mediastinum of the patient and the ICD is configured to deliver electrical stimulation to a heart of the patient using the one or more electrodes.

Abstract: One embodiment of the present subject matter includes an implantable medical device which includes a first power source comprising a first plurality of substantially planar electrodes, the first power source including at least a first power source face, an electronics module including a first substantially planar electronics face, and a second electronics face opposed to the first substantially planar electronics face, with the first substantially planar electronics face adjacent to, and substantially coextensive with, the first power source face and a second power source comprising a second plurality of substantially planar electrodes, the second power source positioned adjacent to and adapted to interface with the second electronics face.

Abstract: A resuscitation device for automatic compression of victim's chest using a compression belt which exerts force evenly over the entire thoracic cavity. The belt is constricted and relaxed through a motorized spool assembly which repeatedly tightens the belt and relaxes the belt to provide repeated and rapid chest compression. An assembly includes various resuscitation devices including chest compression devices, defibrillation devices, and airway management devices, along with communications devices and senses with initiate communications with emergency medical personnel automatically upon use of the device.

Abstract: Apparatus and method for treating an arrhythmia in a patient using an electrotherapy device such as a subcutaneous pacing device. The device applies a series of electrotherapy pulses in response to the presence of the arrhythmia. Various provisions are disclosed for mitigating pain or discomfort as a result of the electrotherapy pulses.

Abstract: A cardiac pacing system comprising one or more leadless cardiac pacemakers configured for implantation in electrical contact with a cardiac chamber and configured to perform cardiac pacing functions in combination with a co-implanted implantable cardioverter-defibrillator (ICD). The leadless cardiac pacemaker comprises at least two leadless electrodes configured for delivering cardiac pacing pulses, sensing evoked and/or natural cardiac electrical signals, and bidirectionally communicating with the co-implanted ICD.

Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to perform arrhythmia discrimination based on activation times. A plurality of different sensing vectors are used to obtain a plurality of IEGMs that collectively enable electrical activations to be detected in the left atrial (LA) chamber, the right atrial (RA) chamber, and at least one ventricular chamber of a patient's heart. For each of a plurality of cardiac cycles, there is a determination, based on the plurality of obtained IEGMs, of an LA activation time, an RA activation time, and a ventricular activation time. Arrhythmia discrimination is then performed based on the determined activation times.

Abstract: A pacing system delivers cardiac protection pacing to protect the heart from injuries associated with ischemic events. The pacing system detects an ischemic event and, in response, initiates one or more cardiac protection pacing sequences each including alternative pacing and non-pacing periods. In one embodiment, the pacing system initiates cardiac protection pacing sequences including at least one postconditioning sequence to protect the heart from a detected ischemic event and a plurality prophylactic preconditioning sequences to protect the heart from probable future ischemic events.

Abstract: A single-chamber implantable device for detecting a patient's atrial activity using a monobody lead is disclosed. The monobody lead (10) includes a ventricular coil (16), a supraventricular coil (18), a distal electrode (14) forming three electrodes for detecting depolarization signals. A generator (12) of the implantable device collects a first unipolar signal (20) between the ventricular coil and the generator housing and a second unipolar signal (22) between the supraventricular coil and the generator housing. An independent component analysis is performed to the detected depolarization signals to determine an estimated atrial activity signal from the first and second unipolar signals.

Abstract: Techniques are provided for use with an implantable medical device for detecting breaches in lead insulation or other lead failures. In one example, bipolar impedance is measured along single-lead vectors (i.e. intra-lead vectors) of a right atrial (RA) lead and a right ventricular (RV) leads. Impedance is also measured along various cross-lead vectors (i.e. inter-lead vectors) between electrodes of the two leads. A derived impedance value is then determined from a combination of the measured impedance values, wherein the derived impedance is sensitive to a shunt impedance arising from a breach within the RV lead. A lead breach is then detected relatively early based on the derived impedance by detecting a significant deviation in derived impedance over time. Unipolar impedance measurements are used to confirm the breach.

Abstract: An implantable cardiac rhythm management (CRM) device includes a sensing and detection circuit that senses at least one cardiac signal and detects cardiac electrical events from the sensed cardiac signal using a detection threshold that is adjusted based on a dynamic noise estimation. The sensed cardiac signal is filtered to produce a filtered cardiac signal having a signal frequency band and a noise signal having a noise frequency band. The noise frequency band is substantially different from the signal frequency band. A dynamic noise floor is produced based on the noise signal and used as the minimum value for the detection threshold. A cardiac electrical is detected when the amplitude of the filtered cardiac signal exceeds the detection threshold.