Abstract: A system embodiment comprises at least one respiration sensor, a neural stimulation therapy delivery module, and a controller. The respiration sensor is adapted for use in monitoring respiration of the patient. The neural stimulation therapy delivery module is adapted to generate a neural stimulation signal for use in stimulating the autonomic neural target of the patient for the chronic neural stimulation therapy. The controller is adapted to receive a respiration signal from the at least one respiration sensor indicative of the patient's respiration, and adapted to control the neural stimulation therapy delivery module using a respiratory variability measurement derived using the respiration signal.

Abstract: 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.

Abstract: Tachyarrhythmia is treated by applying anti-tachycardia pacing through at least one multi-site electrode set located on, in or around the heart. The electrode set is arranged and located such that an electrical activation pattern having a wave-front between substantially flat and concave is generated through a reentrant circuit associated with the tachyarrhythmia. The electrode set may be one of a plurality of predefined, multi-site electrode sets located on, in or around the atria. Alternatively, the electrode set may be formed using at least two selectable electrodes located on, in or around the atria.

Abstract: An implantable electrostimulation assembly, including an electrostimulation device and an electrode lead that is connected to the electrostimulation device when in use, wherein the electrode lead has an optically readable electrode identification and a cable adapter is provided for the temporary insertion between the electrostimulation device and the electrode lead, the adapter comprising optical read means for reading the electrode identification and transmission means for transmitting the same to the electrostimulation device and/or to an assembly-external receiver.

Abstract: Methods, apparatus, and systems are provided to control contraction of the heart. At least one sensing element receives signals indicating electrical activity of sinus rhythm of the heart. The electrical activity is monitored and analyzed to detect an event. In addition, the electrical activity is monitored to detect, for example, premature stimulation and contraction of a portion of the heart, such as the left ventricle. Contraction in the pre-excited portion of the heart is then suppressed using electrical pulses. The heart may then be allowed to contract naturally, or a stimulating pulse may be applied to assist the heart in contracting.

Abstract: One aspect provides a capacitor feedthrough assembly having an electrically conductive member dimensioned to extend at least partially through a feedthrough hole of a case of the capacitor, the conductive member having a passage therethrough.

Abstract: Methods and/or devices for sampling a patient's intrinsic AV conduction time during cardiac therapy that may, e.g., change the AV delays to values based on the AV delays themselves, previously-sampled intrinsic AV conduction times, and/or one or more other parameters directly related to AV delays to provide a time period during which to measure the patient's intrinsic AV conduction time.

Abstract: Various approaches are described for managing refractory periods based on the detection of an evoked response. The heart is paced and an evoked response is detected. At least one refractory period is adapted based on the detected evoked response. Adapting the refractory period may involve, for example, initiating a refractory period, terminating a refractory period, extending a refractory period or modifying one or more parameters of the refractory period. Adapting the refractory period may involve modifying a sensing threshold based on the detected evoked response. The sensing threshold of an atrial sensing channel may be adjusted, for example, to avoid sensing a ventricular evoked response on the atrial channel while allowing sensing of a P-wave on the atrial channel.

Abstract: A method and device for delivering pre-excitation pacing to prevent or reduce cardiac remodeling following a myocardial infarction is described. The pre-excitation pacing is modulated in accordance with an assessment of cardiac function in order to balance the beneficial effects of stress reduction with hemodynamic compromise.

Abstract: Embodiments of the invention provide methods for the detection and treatment of atrial fibrillation (AF) and related conditions. One embodiment provides a method comprising measuring electrical activity of the heart using electrodes arranged on the heart surface to define an area for detecting aberrant electrical activity (AEA) and then using the measured electrical activity (MEA) to detect foci of AEA causing AF. A pacing signal may then be sent to the foci to prevent AF onset. Atrial wall motion characteristics (WMC) may be sensed using an accelerometer placed on the heart and used with MEA to detect AF. The WMC may be used to monitor effectiveness of the pacing signal in preventing AF and/or returning the heart to normal sinus rhythm (NSR). Also, upon AF detection, a cardioversion signal may be sent to the atria using the electrodes to depolorize an atrial area causing AF and return the heart to NSR.

Abstract: One or more multi-electrode lead coupled to a cardiac sensor/stimulator. Each lead includes a lead body extending from one lead proximal end portion to one lead distal end portion. Each lead further includes at least three tissue sensing/stimulation electrodes disposed along the lead body and at least three terminal connections disposed along the lead proximal end. The tissue sensing/stimulation electrodes are each adapted to sense or stimulate a subject's heart. The cardiac sensor/stimulator includes a signal processing circuit adapted to sense the heart in a first instance and stimulate the heart in a second instance by way of one or more tissue electrode configurations. The configurations are selectable from any combination of the tissue sensing/stimulation electrodes of each implanted lead and an indifferent return electrode. In one example, the signal processing circuit automatically selects the tissue electrode configurations.

Abstract: A method or system for computing and/or setting optimal cardiac resynchronization pacing parameters as derived from intrinsic conduction data is presented. The intrinsic conduction data includes intrinsic atrio-ventricular and interventricular delay intervals which may be collected via the sensing channels of an implantable cardiac device. Among the parameters which may be optimized in this manner are an atrio-ventricular delay interval and a biventricular offset interval. In one of its aspects, the invention provides for computing optimum pacing parameters for patients having some degree of AV block or with atrial conduction deficits. Another aspect of the invention relates to a pacing mode and configuration for providing cardiac resynchronization therapy to patients with a right ventricular conduction disorder.

Abstract: Systems and methods for pacing the heart using resynchronization pacing delays that achieve improvement of cardiac function are described. An early activation pacing interval is calculated based on an optimal AV delay and an atrial to early ventricular activation interval between an atrial event and early activation of a ventricular depolarization. The early activation pacing interval for the ventricle is calculated by subtracting the measured AVEA from the calculated optimal AV delay. The early activation pacing interval is initiated responsive to sensing early activation of the ventricle and pacing is delivered relative to expiration of the early activation pacing interval.

Abstract: An RF protection circuit mitigates potentially adverse effects that may otherwise result from electromagnetic interference (e.g., due to MRI scanning of a patient having an implanted medical device). The RF protection circuit may comprise a voltage divider that is deployed across a pair of cardiac electrodes that are coupled to internal circuitry of the implantable medical device. Each leg of the voltage divider may be referenced to a ground of the internal circuit, whereby the different legs are deployed in parallel across different circuits of the internal circuitry. In this way, when an EMI-induced (e.g., MRI-induced) signal appears across the cardiac electrodes, the voltages appearing across these circuits and the currents flowing through these circuits may be reduced. The RF protection circuit may be used in an implantable medical device that employs a relatively low capacitance feedthrough to reduce EMI-induced (e.g., MRI-induced) current flow in a cardiac lead.

Abstract: Systems and methods provide for pacing a heart to improve pumping efficiency of the heart, such as by producing a cardiac fusion response for patient's subject to cardiac resynchronization therapy. A pacing parameter, such as an A-V delay, V-V delay, lead/electrode configuration or vector, is adjusted and a cardiac signal vector representative of all or a portion of one or more cardiac activation sequences is monitored during pacing parameter adjustment. A change in a characteristic of the cardiac signal vector is detected in response to an adjusted pacing parameter, the change indicative of a cardiac fusion response. A pacing therapy may be delivered to produce the cardiac fusion response using the adjusted pacing parameter.

Abstract: Exemplary methods and apparatuses are disclosed that provide for determination of an atrio-ventricular delay on a beat-to-beat basis by determining a P-wave duration from electric signals corresponding to electric potentials in a heart, and determining the atrio-ventricular delay on a beat-to-beat basis such that the atrio-ventricular delay for an individual heart cycle depends on the P-wave duration of a same or an immediately preceding heart cycle.

Abstract: An implantable cardiac rhythm/function management system integrates cardiac contractility modulation (CCM) and one or more other therapies, such as to preserve device safety, improve efficacy, enhance sensing and detection, or enhance therapy effectiveness and delivery. Examples of the one or more other therapies can include pacing, defibrillation/cardioversion, cardiac resynchronization therapy (CRT), or neurostimulation.

Abstract: An implantable medical device, IMD, comprises atrial and ventricular sensing units for sensing atrial or ventricular electric events. The IMD also comprises atrial and ventricular pulse generators for generating atrial or ventricular pacing pulses. The ventricular sensing unit is connectable to a multi-electrode lead to individually sense electric events in a ventricle using multiple electrode pairs implanted at different ventricular sites. A controller blanks the ventricular sensing unit during a blanking period following delivery of an atrial stimulating pulse by the atrial pulse generator and activates the ventricular sensing unit at the expiry of the blanking period. Due to the lower propagation speed of PVC depolarization waves and the multi-site sensing, a PVC depolarization wave initiated at a ventricular site during the blanking period can be detected by the IMD.

Abstract: An implantable pulse generator includes a header, a can and a feedthru. The feedthru is mounted in a wall of the can and includes an electrically insulating core, a PCB, a shield, a chip capacitor, a power circuit and a ground circuit. A first side of the PCB abuts against the core and a second side of the PCB abuts against an edge of the shield. The chip capacitor is mounted on the second side of the PCB. The chip capacitor is enclosed in a volume defined by an interior of the shield and the second side of the PCB. A first electrical contact of the chip capacitor is electrically coupled to the power circuit, and a second electrical contact of the chip capacitor is electrically coupled to the ground circuit.

Abstract: A cardiac medical device and associated method control delivery of dual chamber burst pacing pulses in response to detecting tachycardia. In one embodiment, a single chamber pacing pulse is delivered in response to detecting a tachycardia. Dual chamber pacing pulses are delivered subsequent to the single chamber pacing pulse. An intrinsic depolarization is sensed subsequent to delivering the dual chamber pacing pulses. The tachycardia episode is classified in response to the sensed intrinsic depolarization.

Abstract: The disclosure herein relates generally to methods for treating heart conditions using vagal stimulation, and further to systems and devices for performing such treatment. Such methods may include monitoring physiological parameters of a patient, detecting cardiac conditions, and delivering vagal stimulation (e.g., electrical stimulation to the vagus nerve or neurons having parasympathetic function) to the patient to treat the detected cardiac conditions.

Abstract: This document discusses, among other things, systems, devices, and methods for measuring cardiac impedances and producing one or more resynchronization index parameters each indicative of a cardiac synchrony or asynchrony using the measured cardiac impedances. In one example, the one or more resynchronization index parameters are used to adjust one or more pacing parameters of a cardiac resynchronization therapy.

Abstract: An implantable cardiac rhythm/function management system integrates cardiac contractility modulation (CCM) and one or more other therapies, such as to preserve device safety, improve efficacy, enhance sensing and detection, or enhance therapy effectiveness and delivery. Examples of the one or more other therapies can include pacing, defibrillation/cardioversion, cardiac resynchronization therapy (CRT), or neurostimulation.

Abstract: Techniques are provided for controlling therapy provided by the implantable cardiac stimulation device based on cardiogenic impedance. A cardiogenic impedance signal (or intracardiac impedance signal) is an impedance signal representative of the beating of the heart of the patient in which the device is implanted. The cardiogenic impedance signal is sensed along a sensing vector passing through at least a portion of the heart so that the sensed impedance is affected by the mechanical beating of the heart along that sensing vector. Pacing therapy is automatically and adaptively adjusted based on the cardiogenic impedance signal. For example, pacing timing parameters such as the atrioventricular delay and the inter-ventricular delay may be adjusted. Preferably, the adjustments are adaptive, i.e. the adjustments are performed in a closed-loop so as to adapt the adjustments to changes in the cardiogenic impedance signal so as to optimize therapy.

Abstract: An implantable lead connector configured for long term implantation and to electrically interconnect multiple medical devices and to channel electrical signals between said interconnected devices and a target organ, comprising: a first port adapted to receive a first signal suitable to stimulate a target tissue, a second port adapted to receive a second signal suitable to stimulate a target tissue, and a third port configured to connect to a target organ, wherein at least one of said first and second ports is configured to connect to a signal generator not integrated with said connector.

Abstract: An apparatus for determining tissue versus fluid components of an organ include a detector that generates a detector signal based on electrical signals derived from tissue and fluid. The apparatus includes a signal processor in communication with the detector which subtracts in real time a tissue component from the detector signal and produces a fluid volume signal. A method for monitoring a patient's fluid volume of a patient's organ. An apparatus for monitoring a patient's organ. A method for monitoring a patient's organ. A method to piggyback an admittance system onto a AICD/Bi-ventricular Pacemaker for a heart of a patient, in particular a weakened heart having features consistent with congestive heart failure. An apparatus for monitoring an organ, such as a heart, lungs, brain, skeletal muscle, and bladder of a patient which includes a detector which detects the admittance of the organ.

Abstract: An implantable medical device (IMD) and methods of operating the same to treat a tachyarrhythmia are disclosed herein. In accordance with this method, an arrhythmia of the heart is classified based on one or more supraventricular tachycardia (SVT) rejection rules, which differentiate between a first group of heart rhythms that do not require treatment and a second group of heart rhythms that possibly require treatment. Diagnostic/therapeutic pacing can then be performed to further discriminate the second group of heart rhythms as being within a first sub-group of heart rhythms and a second sub-group of heart rhythms which are to be treated by applying a ventricular tachycardia (VT)/ventricular fibrillation (VF) therapy sequence. In another implementation, the order in which the IMD performs diagnostic/therapeutic pacing and analyzes passive detection and classification criteria can be reversed.

Abstract: A leadless implantable medical device (LIMD) comprises a housing configured to be implanted entirely within a single local ventricular chamber of the heart near a local apex region. A base on the housing is configured to be secured to tissue of interest, while a distal electrode is provided on the base and extends outward such that, when the device is implanted in the local chamber, the distal electrode is configured to engage the distal apex region at a distal activation site within the conduction network of the adjacent ventricular chamber.

Abstract: Techniques are provided for use with implantable medical devices to deliver paired or coupled postextrasystolic potentiation (PESP) pacing using split or bifurcated anodic and cathodic pulses. In a paired pacing example, a single-phase anodic pulse is delivered by the device that has sufficient amplitude to depolarize and contract myocardial tissue. During or just following a subsequent relative refractory period, a single-phase cathodic stimulation pulse is delivered that has sufficient amplitude to depolarize but not contract myocardial tissue, i.e., the cathodic pulse provides for PESP. In a coupled pacing example, the single-phase anodic pulse is delivered during or just following the relative refractory period of a first cardiac cycle; whereas the single-phase cathodic pulse is delivered during or immediately following the relative refractory period of the next consecutive cardiac cycle.

Abstract: Techniques are provided for use with implantable medical devices to deliver packed pacing using split or bifurcated pulses of opposing polarity in different cardiac cycles. In one example, packed single-phase pulses are delivered by the device during a first cardiac cycle that serve to stimulate heart tissue. During the next cardiac cycle, packed single-phase stimulation pulse of opposing polarity are delivered that serve to recharge the pacing capacitors and also serve to stimulate heart tissue. By separating the pulses into separate cardiac cycles, near simultaneous multisite packed stimulation can be achieved within each cardiac cycle while providing for charge balancing and without interfering with sensing. Non-packed pacing with bifurcated pulses is also described.

Abstract: A system for providing electrical stimulation of cervical vagus nerves for treatment of chronic cardiac dysfunction with bounded titration is provided. The system includes a patient-operable external controller to transmit a plurality of unique signals. The system further includes an implantable neurostimulator, which includes a pulse generator to deliver electrical therapeutic stimulation tuned to restore autonomic balance through continuously-cycling, intermittent and periodic electrical pulses that result in creation and propagation (in both afferent and efferent directions) of action potentials within the cervical vagus nerve of a patient through a pair of helical electrodes via an electrically coupled nerve stimulation therapy lead.

Abstract: A measurement system may comprise a sensor wire, a sensor, and a transceiver unit. The sensor wire may comprise an insertable portion configured to be inserted in a blood vessel of a patient's body. The sensor is disposed within the insertable portion at a distal end of the sensor wire. The sensor is configured to measure or detect a non-physiological parameter when inserted inside the patient. The transceiver unit is adapted to generate a communication signal and to transfer information related to the non-physiological parameter to an external communication module using the communication signal. The communication signal includes sensor values related to the non-physiological parameter. The transceiver unit may comprise a housing adapted to be connected to a proximal end of the sensor wire and configured to remain external to the patient's body.

Abstract: A late potential detecting system has an implantable medical device connected to at least one cardiac lead having implantable electrodes positioned at different sites of a ventricle myocardium. A sampling unit of the implantable medical device records electrogram samples for the different implantable electrodes to get different sample sets. The electrogram samples of the sample sets are time synchronized and magnitude potential representations of the potential data of the electrogram samples are determined. The magnitude potential representations of the time synchronized electrogram samples are then co-processed and used for determining a parameter that is indicative of any late potentials of the monitored ventricle.

Abstract: A leadless intra-cardiac medical device (LIMD) configured to be implanted entirely within a heart of a patient includes a housing configured to be securely attached to an interior wall portion of a chamber of the heart, and a stabilizing intra-cardiac (IC) device extension connected to the housing. The stabilizing IC device extension may include a stabilizer arm, and/or an appendage arm, or an elongated body or a loop member configured to be passively secured within the heart.

Abstract: Systolic timing intervals are measured in response to delivering pacing energy to a pacing site of a patient's heart. An estimate of a patient's acute response to cardiac resynchronization therapy (CRT) for the pacing site is determined using the measured systolic timing intervals. The estimate is compared to a threshold. The threshold preferably distinguishes between acute responsiveness and non-responsiveness to CRT for a patient population. An indication of acute responsiveness to CRT for the pacing site may be produced in response to the comparison.

Abstract: Techniques for controlling one or more modular circuits (“satellites”) that are intended for placement in a subject's body. The one or more satellites are controlled by sending signals over a bus that includes first and second conduction paths. Also coupled to the bus in system embodiments is a device such as a pacemaker that provides power and includes control circuitry. Each satellite includes satellite circuitry and one or more effectors that interact with the tissue. The satellite circuitry is coupled to the bus, and thus interfaces the controller to the one or more effectors, which may function as actuators, sensors, or both. The effectors may be electrodes that are used to introduce analog electrical signals (e.g., one or more pacing pulses) into the tissue in the local areas where the electrodes are positioned (e.g., heart muscles) or to sense analog signals (e.g., a propagating depolarization signal) within the tissue.

Abstract: An implantable medical device, IMD, comprises atrial and ventricular sensing units for sensing atrial or ventricular electric events. The IMD also comprises atrial and ventricular pulse generators for generating atrial or ventricular pacing pulses. A controller controls the operation of the IMD (100) according to a first mode, in which the ventricular pulse generator is prevented from generating a back-up pulse if an evoked response detector fails to detect evoked response to a delivered ventricular pacing pulse, and a second mode, in which the ventricular pulse generator is controlled to generate a back-up pulse if no evoked response is detected following delivery of a ventricular stimulating pulse. The controller switches operation from the first mode to the second mode based on the evoked response detector failing to detect an evoked response to a delivered ventricular pacing pulse.

Abstract: An exemplary method includes delivering a cardiac pacing therapy using an electrode configuration for left ventricular, single site pacing or left ventricular, multi-site pacing, measuring a series of interventricular conduction delays using the left ventricular pacing and right ventricular sensing (IVCD-LR), comparing the interventricular conduction delay values to a limit and, based on the comparison, deciding whether to change the electrode configuration for the left ventricular pacing. Other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: A method and system for managing refractory periods in a cardiac rhythm management device configured for biventricular or biatrial sensing. Refractory periods for each channel of the pacemaker are provided by interval timers that are triggered by sensed or paced events in order to prevent misinterpretation of sensing signals.

Abstract: During auto-threshold, autocapture, or other evoked response sensing, post-pace artifact is reduced by using a smaller coupling capacitor value than what is used when not in such an evoked response sensing configuration. This can be accomplished by borrowing another capacitor for use as the coupling capacitor. The borrowed capacitor can be a backup pacing capacitor from the same or a different pacing channel. The borrowed capacitor can also be a coupling capacitor from a different pacing channel.

Abstract: Generally, the disclosure is directed one or more methods or systems of cardiac pacing employing a right ventricular electrode and a plurality of left ventricular electrodes. Pacing using the right ventricular electrode and a first one of the left ventricular electrodes and measuring activation times at other ones of the left ventricular electrodes. Pacing using the right ventricular electrode and a second one of the ventricular electrodes and measuring activation times at other ones of the left ventricular electrodes. Employing sums of the measured activation times to select one of the left ventricular electrodes for delivery of subsequent pacing pulses.

Abstract: A neural stimulation system senses autonomic activities and applies neural stimulation to sympathetic and parasympathetic nerves to control autonomic balance. The neural stimulation system is capable of delivering neural stimulation pulses for sympathetic excitation, sympathetic inhibition, parasympathetic excitation, and parasympathetic inhibition.

Abstract: A method for operating an implantable medical device to obtain substantially synchronized closure of the mitral and tricuspid valves based on sensed heart sounds includes sensing an acoustic energy; producing signals indicative of heart sounds of the heart of the patient over predetermined periods of a cardiac cycle during successive cardiac cycles; calculating a pulse width of such a signal; and iteratively controlling a delivery of the ventricular pacing pulses based on calculated pulse widths of successive heart sound signals to identify an RV interval or VV interval that causes a substantially synchronized closure of the mitral and tricuspid valve. A medical device for optimizing an RV interval or VV interval based on sensed heart sounds implements such a method and a computer readable medium encoded with instructions causes a computer to perform such a method.

Abstract: A nerve stimulation apparatus performs nerve stimulation of a required level while reducing the adverse effect on the heart and on the detection of a cardiac event. Provided is a nerve stimulation apparatus that includes a stimulation signal output unit that outputs a nerve stimulation signal; a cardiac event detector that detects a cardiac event; and a controller that controls the stimulation signal output unit so as to output a nerve stimulation signal having a smaller intensity in a non-refractory period than that in a cardiac refractory period that is obtained on the basis of the cardiac event detected by the cardiac event detector.

Abstract: A method for mapping abnormal electrical activity, including obtaining electrical signal data from respective locations in a heart of a living subject, and automatically analyzing the signal data to identify complex fractionated electrograms (CFEs) therein. The method further includes analyzing the CFEs so as to identify reentry locations comprised in the respective locations, and displaying information derived from the identification in relation to a map of the heart.

Abstract: A device for detecting cardiac ischemia is disclosed. The device includes a processor that is configured to distinguish between two different heart beats types such as left bundle branch block beats and normal sinus beats. The processor applies different ischemia tests to the two different beat types, and generates alert when it detects ischemia.

Abstract: A method of operating a cardiac therapy system to deliver cardiac resynchronization therapy (CRT) pacing that includes pacing both ventricles or pacing only the left ventricle is described. Delivery of the CRT pacing to one or both ventricles is scheduled for a cardiac cycle. If an intrinsic depolarization of a ventricle is detected during a pacing delay of the ventricle, then the scheduled CRT pacing to the ventricle is inhibited for the cycle. The intrinsic interval of the ventricle, such as the intrinsic atrioventricular interval concluded by the intrinsic depolarization, is measured. During a subsequent cardiac cycle, the pacing delay of the ventricle is decreased to be less than or equal to the measured intrinsic interval. Capture of the ventricle is verified after pacing is delivered during the subsequent cardiac cycle.

Abstract: Exemplary methods are described for providing responsive vascular control with or without cardiac pacing. An implantable device with responsive vascular and cardiac controllers interprets physiological conditions and responds with an appropriate degree of vascular therapy applied as electrical pulses to a sympathetic nerve. In one implementation, an implantable device is programmed to deliver the vascular therapy in response to low blood pressure or orthostatic hypotension. The device may stimulate the greater splanchnic nerve, to effect therapeutic vasoconstriction. The vascular therapy is dynamically adjusted as the condition improves. In one implementation to benefit impaired physical mobility, vascular therapy comprises vasoconstriction and is timed to coincide with a recurring segment of the cardiac cycle. The vasoconstriction assists circulation and venous return in the lower limbs of inactive and bedridden individuals.

Abstract: A cardiac rhythm management system selects one of multiple electrodes associated with a particular heart chamber based on a relative timing between detection of a depolarization fiducial point at the multiple electrodes, or based on a delay between detection of a depolarization fiducial point at the multiple electrodes and detection of a reference depolarization fiducial point at another electrode associated with the same or a different heart chamber. Subsequent contraction evoking stimulation therapy is delivered from the selected electrode.

Abstract: Methods and systems involve adjusting an energy used for safety pacing based on the capture threshold. The safety pacing energy may be adjusted prior to a capture threshold test. During the capture threshold test, backup safety paces are delivered using the adjusted pacing energy. Following suspension of automatic capture verification, the device may enter a suspension mode. During the suspension mode, safety pacing pulses are delivered using a pacing energy adjusted based on capture threshold.