Abstract: A method for pacing a left ventricle of a heart includes delivering a pacing pulse via a first electrode to activate a first papillary muscle and another pacing pulse via a second electrode to activate a second papillary muscle.

Abstract: A medical device having a plurality of electrodes sensing cardiac signals, and a microprocessor operably coupled to the plurality of electrodes and configured to determine a cumulative atrioventricular interval (AVI) burden in response to the sensed cardiac signals, and to switch operation of the device between a minimal biventricular pacing (MBVP) mode and a conditional triple chamber pacing (CTCP) mode in response to the determined AVI burden.

Abstract: Techniques are provided for use by implantable medical devices for controlling ventricular pacing, particularly during atrial fibrillation. In one example, during a V sense test for use in optimizing ventricular pacing, the implantable device determines relative degrees of variation within antecedent and succedent intervals detected between ventricular events sensed on left ventricular (LV) and right ventricular (RV) sensing channels. Preferred or optimal ventricular pacing delays are then determined, in part, based on a comparison of the relative degrees of variation obtained during the V sense test. In another example, during RV and LV pace tests, the device distinguishes QRS complexes arising due to interventricular conduction from QRS complexes arising due to atrioventricular conduction from the atria, so as to permit the determination of correct paced interventricular conduction delays for the patient. The paced interventricular conduction delays are also used to optimize ventricular pacing.

Abstract: A method for use in an implantable medical device system, comprising: selecting a first sensing electrode operatively disposed in a first heart chamber; setting a first sensing window corresponding to cardiac electrical events occurring in a second heart chamber; enabling a first sense amplifier coupled to the first sensing electrode during the first sensing window; sensing a first signal corresponding to cardiac electrical events occurring in the second heart chamber during the first sensing window using the first sensing electrode; and transmitting the first signal from an implantable medical device to an external monitor.

Abstract: A method for operating a cardiac pacemaker in which the mode of operation of the pacemaker is altered in response to detecting an episode of atrial tachycardia. In accordance with the invention, the pacemaker's pacing mode is altered in a manner that attempts to maintain hemodynamic stability during the atrial tachycardia. Such a mode switch is particularly applicable to pacemaker patients suffering from some degree of congestive heart failure.

Abstract: This document discusses, among other things, systems and methods to discriminate between a ventricular tachyarrhythmia (VT) and a supraventricular tachyarrhythmia (SVT), such as upon detecting sudden onset and one-to-one tachycardia. In certain examples, a detected tachyarrhythmia is analyzed to determine whether it is sudden onset and 1:1. If so, a first fast beat is identified. One or more ventricular intervals in close proximity to the first fast beat are analyzed to determine an initial classification of either VT or SVT. The initial classification is used to adjust a morphological feature correlation coefficient (FCC) threshold. A morphology analysis is performed with the adjusted FCC threshold value to yield a secondary classification.

Abstract: The disclosure describes techniques for delivering vagal stimulation to decrease the ventricular rate response during an atrial tachyarrhythmia, such as atrial fibrillation. Decreasing the ventricular rate response during an atrial tachyarrhythmia may facilitate increased ventricular pacing for cardiac resynchronization therapy (CRT), and may also reduce the likelihood of inappropriately detecting a ventricular tachyarrhythmia during the atrial tachyarrhythmia. Furthermore, the vagal stimulation may augment vagal tone, which may facilitate long term left ventricular reverse remodeling and decrease atrial and ventricular arrhythmic burden in heart failure patients. An example system that delivers CRT comprises a processor that detects an atrial tachyarrhythmia in one or more atria of the heart, and monitors at least one of a ventricular rate or degree of ventricular pacing subsequent to the detected atrial arrhythmia.

Abstract: Embodiments of the invention are related to systems and methods for setting parameters of implantable medical devices, amongst other things. In an embodiment, the invention includes a method for programming an implantable medical device including sensing concentrations of a predictive marker such as ET-1 in a patient, selecting programming parameter values based on the sensed concentrations of the predictive marker, and implementing the selected programming parameter values. In an embodiment the invention includes a method for detecting arrhythmia in a patient including sensing concentrations of the predictive marker in a patient, selecting a level of stringency to be used in an arrhythmia detection module based on the sensed concentrations of the predictive marker, sensing electrical signals in the patient, and evaluating the sensed electrical signals for indicia of an arrhythmia using the arrhythmia detection module. Other embodiments are also included herein.

Abstract: The invention relates to a method for checking ECG signals measured by an ECG measuring device having at least three electrodes for the presence of interference errors. At least three voltages are measured on a closed circulation path across the electrodes of the ECG measuring device. A monitoring value is calculated from the three measured voltages. A presence of an error is checked by determining a deviation of the monitoring value from a reference value. An error signal is outputted if an error is presented. The ECG measuring device has a further processing unit for processing voltage signals between a different pair of electrodes and a monitoring unit for calculating the monitoring value.

Abstract: Disclosed herein are various embodiments of methods, systems and devices for detecting atrial fibrillation (AF) in a patient. According to one embodiment, a patient places his or her left and right hands around left and right electrodes and a hand-held atrial fibrillation detection device acquires an electrocardiogram (ECG) from the patient over a predetermined period of time such as, by way of example, one minute. After acquiring the ECG from the patient, the device processes and analyzes the ECG and makes a determination of whether the patient has AF. The device may further be configured to provide a visual or audio indication of whether the patient has AF, or does not have AF. The device may be employed in a health care provider's office without the need for complicated or expensive diagnostic equipment, and is capable of providing an on-the-spot and low-cost diagnosis of AF.

Abstract: Validated atrial and/or ventricular interval decreases are used to discriminate between VT and SVT. Atrial and/or ventricular intervals are monitored in order to detect decreases in such intervals (which are indicative in increases in rate). The atrial intervals can be, e.g., AA intervals, and the ventricular intervals can be, e.g., VV intervals. A detected atrial and/or ventricular interval decrease can be a decrease that is greater than an interval decrease threshold. Detected atrial and/or ventricular interval decreases can be validated by examining atrial and/or ventricular intervals before and after a detected atrial and/or ventricular interval decrease. The use of the validated atrial and/or ventricular interval decreases to classify an arrhythmia as SVT or VT can be called arrhythmia initiation analysis, since it is believed to determine whether the initiation of the arrhythmia is in an atrium or a ventricle.

Abstract: Detected changes in atrial activation can be used to discriminate between hemodynamically stable and hemodynamically unstable tachyarrhythmias.

Abstract: An implantable neural stimulation system includes an implantable medical device having a neural stimulation circuit and at least one implantable lead configured to allow one or more stimulation electrodes to be placed in one or more lymphatic vessels of a patient, such as the patient's thoracic duct and/or vessels branching from the thoracic duct. Neural stimulation pulses are delivered from the implantable medical device to one or more target regions adjacent to the thoracic duct or the vessels branching from the thoracic duct through the one or more stimulation electrodes.

Abstract: An implantable medical device and associated method classify therapy outcomes and heart rhythms in association with therapy outcome. A therapy success time interval is started in response to delivering an arrhythmia therapy. If normal sinus rhythm is detected after the therapy success time interval expires, the delivered therapy is classified as unsuccessful and the detected arrhythmia is classified as a self-terminating rhythm.

Abstract: Techniques for morphologic discrimination between beats of a tachyarrhythmia episode are described for selecting delivery of appropriate therapy. An exemplary method comprises nonordered binning of digitized amplitude values of signals associated with cardiac depolarizations. Monomorphic VT is discriminated from polymorphic VT without signal alignment. One exemplary method involves sensing electrical signals associated with depolarizations of a patient's heart during a tachyarrhythmia episode. The sensed electrical signals are converted to digital values and stored. The stored digital values are normalized and binned. At most, 5 pairs of beats or depolarizations are compared for morphologic similarity by determining the similarity between the binned values associated with each pair. The result of the comparison is used to select and deliver therapy to the patient.

Abstract: This document discusses, among other things, detection of a sudden onset of a tachyarrhythmia. A sudden onset of tachyarrhythmia is determined by monitoring changes in intrinsic ventricular rate, such as by using one or more sensing channels in the ICD. A lowest tachyarrhythmia rate threshold is accompanied by a slightly lower “hysteresis tachyarrhythmia rate threshold.” If a sudden onset of tachyarrhythmia is declared, the sudden onset status is not reset by the ventricular rate falling below the lowest tachyarrhythmia rate threshold, but is instead reset by the ventricular rate falling below the slightly lower hysteresis tachyarrhythmia rate threshold.

Abstract: An external defibrillator having a battery; a capacitor electrically communicable with the battery; at least two electrodes electrically communicable with the capacitor and with the skin of a patient; a controller configured to charge the capacitor from the battery and to discharge the capacitor through the electrodes; and a support supporting the battery, capacitor, electrodes and controller in a deployment configuration, the defibrillator having a maximum weight per unit area in the deployment configuration of 0.1 lb/in2 and/or a maximum thickness of 1 inch. The support may be a waterproof housing.

Abstract: Method and apparatus for preventing heart rhythm disturbances by recording cardiac electrical activity, measuring beat-to-beat variability in the morphology of electrocardiographic waveforms, and using the measured beat-to-beat variability to control the delivery of electrical impulses to the heart during the absolute refractory period.

Abstract: A cardiac rhythm management system for providing a plurality of therapy modalities. For example, the system may include a cardiac resynchronization therapy module for providing cardiac resynchronization therapy and a pacemaker module for providing bradycardia therapy, as well as a selector module coupled to the cardiac resynchronization therapy module and the bradycardia module. The selector module may select an operating mode from among a plurality of operating modes including the cardiac resynchronization therapy module and the pacemaker module. Various manual and automatic methods may be used to select the operating mode. In addition, a reversion management system may be included to assist the cardiac rhythm management system to recover in case of a disruption to the system.

Abstract: A combination cardiac stimulator for CRT stimulation and CCM stimulation, which is connected to a rhythm evaluation unit which can either detect a sinus rhythm that is present, or classify an atrial arrhythmia, and which comprises an additional therapy selection unit, wherein the therapy selection unit selects the delivery of either CRT therapy or CCM therapy on the basis of the classification of the atrial rhythm such that CRT therapy is preferred in the case of sinus rhythm, and CCM therapy is delivered in the case of atrial arrhythmia.

Abstract: Techniques are provided for use by implantable medical devices for controlling ventricular pacing, particularly during atrial fibrillation. In one example, during a V sense test for use in optimizing ventricular pacing, the implantable device determines relative degrees of variation within antecedent and succedent intervals detected between ventricular events sensed on left ventricular (LV) and right ventricular (RV) sensing channels. Preferred or optimal ventricular pacing delays are then determined, in part, based on a comparison of the relative degrees of variation obtained during the V sense test. In another example, during RV and LV pace tests, the device distinguishes QRS complexes arising due to interventricular conduction from QRS complexes arising due to atrioventricular conduction from the atria, so as to permit the determination of correct paced interventricular conduction delays for the patient. The paced interventricular conduction delays are also used to optimize ventricular pacing.

Abstract: Disclosed are methods and systems for treating epilepsy by stimulating a main trunk of a vagus nerve, or a left vagus nerve, when the patient has had no seizure or a seizure that is not characterized by cardiac changes such as an increase in heart rate, and stimulating a cardiac branch of a vagus nerve, or a right vagus nerve, when the patient has had a seizure characterized by cardiac changes such as a heart rate increase.

Abstract: Techniques are provided for controlling ventricular pacing during an episode of atrial fibrillation (AF) for use by a pacemaker, implantable cardioverter-defibrillator (ICD) or other implantable medical device. In one example, upon detection of AF, the underlying intrinsic ventricular rate of the patient is determined prior to delivering any ventricular pacing. Then, a ventricular pacing procedure—such as dynamic ventricular overdrive (DVO) pacing—is activated to reduce ventricular rate variability to mitigate the adverse effects of AF. The ventricular pacing procedure employed during AF is controlled based on a maximum ventricular rate set relative to the underlying intrinsic ventricular rate so as to keep an overall ventricular rate below the maximum rate.

Abstract: A method of identifying potential driver sites for cardiac arrhythmias includes acquiring a plurality of electrograms from a plurality of locations on at least a portion of a patient's heart. Using the acquired electrograms, at least one electrical activity map is generated. Desirable electrical activity maps include complex fractionated electrogram standard deviation and mean maps, dominant frequency maps, peak-to-peak voltage maps, and activation sequence maps. Using one or more of these maps (e.g., by analyzing one or more electrogram morphological characteristics represented by these maps), at least one potential driver site can be detected.

Abstract: Systems and methods are provided for use by implantable medical devices equipped to deliver multi-site left ventricular (MSLV) pacing. Sequential MSLV is associated with a relatively long post-ventricular atrial blanking (PVAB) period that might limit the detection of pathologic rapid organized atrial tachycardias (OAT). In one example, sequential MSLV cardiac resynchronization therapy (CRT) pacing is delivered within a tracking mode. A possible atrial tachycardia is detected based on the atrial rate exceeding an atrial tachycardia assessment rate (ATAR) threshold. The device then switches to either single-site LV pacing or simultaneous MSLV pacing, thereby effectively shortening the PVAB to detect additional atrial events that might otherwise be obscured, and thereby permitting the device to more reliably distinguish OATs (such as atrial flutter) from sinus tachycardia.

Abstract: A cardiac medical device and associated method control delivery of anti-tachycardia pacing (ATP) in response to detecting tachycardia. In one embodiment, an initial set of single chamber pacing pulses are delivered in a single one of the atrium and the ventricle, the other one of the atrium and the ventricle being a non-paced chamber during the initial set of single chamber pacing pulses. The device detects simultaneity between a sensed event in the non-paced chamber and one of the single chamber pacing pulses and delivers ATP in both the atrium and the ventricle in response to detecting the simultaneity.

Abstract: An apparatus comprises a cardiac signal sensing circuit, a physiologic sensor circuit configured to provide a physiologic sensor signal representative of mechanical cardiac activity, a therapy circuit, and a control circuit. The control circuit includes a cardiac depolarization detection circuit, a tachyarrhythmia detection circuit, and a timer circuit. A time interval between a mechanical cardiac event and a detected fiducial electrical cardiac event is monitored. The control circuit is configured to correct the monitored time interval for variation with heart rate to form a corrected electromechanical time interval, initiate anti-tachyarrhythmia therapy when the corrected electromechanical time interval satisfies a specified time interval threshold value during a detected episode of tachyarrhythmia, and withhold anti-tachyarrhythmia therapy otherwise.

Abstract: An implantable medical device for monitoring tissue perfusion that includes a light source emitting a light signal and a light detector receiving emitted light scattered by a volume of body tissue. The light detector emits a signal having an alternating current component corresponding to the pulsatility of blood flow in the body tissue volume. A processor receives the current signal and determines a patient condition in response to the alternating component of the current signal.

Abstract: A system can coordinate operation of a cardiac function management (CFM) device and a renal device, such as during a vulnerable period in which a patient has an increased risk of tachyarrhythmia.

Abstract: A method is provided, including identifying that a subject is at risk of suffering from atrial fibrillation (AF). Responsively to the identifying, a risk of an occurrence of an episode of the AF is reduced by coupling an electrode device to a site of a subject containing parasympathetic nervous tissue; driving, by a control unit, the electrode device to apply an electrical current to the site not responsively to any physiological parameters sensed by any device directly or indirectly coupled to the control unit; and configuring the current to stimulate autonomic nervous tissue in the site. Other embodiments are also described.

Abstract: In a method and implantable medical device for ventricular tachyarrhythmia detection and classification, upon detection of a ventricular tachyarrhythmia based on an electrocardiogram signal, cardiogenic impedance data representative of ventricular volume dynamics are collected and used for classifying the detected tachyarrhythmia as stable or unstable. In the latter case but typically not in the former case, defibrillation shocks or other forms of therapy are applied to combat the unstable ventricular tachyarrhythmia.

Abstract: Techniques for determining whether a lead related condition exists based on analysis of a cardiac electrical signal associated with a non-sustained tachyarrhythmia (NST) are described. In some examples, the techniques include determining the duration of intervals between consecutive cardiac events, e.g., R-R intervals, during an NST. The techniques may further include determining one or more metrics based on the durations of the intervals during the NST. Examples of metrics include an average, a minimum, a maximum, a range, a median, a mode, or a mean. A lead related condition is identified based on the values of the one or more metrics, e.g., by comparison to respective thresholds. In some examples, an alert is provided or a therapy modification is suggested if a lead related condition is identified.

Abstract: In various method embodiments, a supraventricular arrhythmia event is detected, and a supraventricular arrhythmia treatment, including neural stimulation to elicit a sympathetic response, is delivered in response to a detected supraventricular arrhythmia event. Some embodiments detect a precursor for a supraventricular arrhythmia episode, and deliver prophylactic neural stimulation to avoid the supraventricular arrhythmia event. Some embodiments detect a supraventricular arrhythmia episode, and deliver therapeutic neural stimulation for the supraventricular arrhythmia event.

Abstract: The disclosure describes techniques for delivering electrical stimulation to decrease the ventricular rate response during an atrial tachyarrhythmia, such as atrial fibrillation. AV nodal stimulation is employed during an atrial tachyarrhythmia episode with rapid ventricular conduction to distinguish ventricular tachyarrhythmia from supraventricular tachycardia and thereby prevent delivering inappropriate therapy to a patient.

Abstract: A system and method for selectively treating a ventricular tachycardia based on sensed atrial and ventricular intervals from the patient's heart. A detection window of the ten most recent atrial and ventricular intervals are analyzed for the occurrence of either tachycardia or fibrillation. When a majority of the sensed intervals are satisfied, the apparatus starts a duration time interval. Ventricular intervals and atrial intervals are compare, ventricular interval greater than the atrial interval by a bias factor the system delivers tachycardia therapy to the heart. Alternatively, the method withholds tachycardia therapy to the heart when the atrial rate is classified as atrial fibrillation and the ventricular response is unstable.

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: An implantable medical system may include an implantable medical lead including at least one electrode and an implantable medical device. The implantable medical device comprises an electromagnetic interference (EMI) detection module that monitors for one or more particular characteristics of EMI. A control module is configured to control a therapy module to generate single stimulation pulses while operating the IMD in a first operating mode. In response to detecting the condition indicative of the presence of EMI, the control module switches the IMD from the first operating mode to a second operating mode and generates at least one group of two or more stimulation pulses in close proximity to one another in place of a single stimulation pulse while operating the IMD in the second operating mode.

Abstract: Methods and systems are directed to detecting atrial tachyarrhythmia. A plurality of A-A intervals is detected. The detected A-A intervals are selected and used to detect atrial tachyarrhythmia. Selecting A-A intervals may be based on determining that A-A intervals are qualified. Qualified A-A intervals may be determined if a duration of the particular A-A interval falls outside a predetermined duration range, for example. Qualified A-A intervals may also be determined based on events occurring between consecutively sensed atrial events of the particular A-A interval, and whether the duration of the particular A-A interval falls within the predetermined duration range, for example.

Abstract: A method and apparatus for treating a mitral valve prolapse and providing embolic protection in a patient is disclosed. An embolic protection filter is delivered to the left atrium and placed in the blood flow exiting the left atrium of the heart. The filter is secured in the heart of a patient. A shaping member is delivered to the mitral valve of the heart and secured in the heart.

Abstract: With a method and apparatus for detecting cardiac arrhythmias during overdrive pacing, a maximum paced rate and a reduced paced rate for a heart are determined, the maximum paced rate being higher than the reduced paced rate. The heart is paced at the maximum paced rate. After the heart is paced at the maximum paced rate for a predetermined amount of time, the heart is paced at the reduced paced rate.

Abstract: 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.

Abstract: The disclosure includes methods and systems for treating ventricular arrhythmias. Embodiments include an implantable cardiac device or system including a determining module that determines a value of a parameter indicative of a rate of an intrinsic pacemaker of a heart of a patient experiencing fast ventricular arrhythmia (FVA) and a delivery module, programmed to deliver therapy for ventricular arrhythmias to a patient. Some methods include determining a value of a parameter indicative of a rate of an intrinsic pacemaker of a heart of a patient experiencing an FVA; if the value indicates the rate is about equal to or higher than a threshold, delivering a first therapy to the patient for terminating the FVA, and if the value indicates the rate is lower than the threshold, delivering a second therapy, different from the first therapy, to the patient for terminating the FVA.

Abstract: Techniques are described for discriminating ventricular tachycardia (VT) from supraventricular tachycardia (SVT) in circumstances when the ventricular rate exceeds the atrial rate (i.e. V>A). In one example, an initial atrial rate is detected while employing adjustable atrial channel detection parameters that can affect the detection of the true atrial rate—such as a post-ventricular atrial blanking (PVAB) interval or an atrial channel sensitivity level. If the ventricular rate exceeds a VT rate zone threshold with V>A, the device does not immediately deliver high voltage shock therapy as done in other devices. Rather, the device instead selectively adjusts the atrial channel detection parameter(s) to determine if the true atrial rate is equal to the ventricular rate. If so, then such is an indication that the arrhythmia might be SVT rather than VT and various discrimination procedures are employed to distinguish SVT from VT before therapy is delivered.

Abstract: An apparatus and method to discriminate cardiac events by sensing atrial and ventricular depolarizations having associated refractory periods thereafter. A fast ventricular rate is detected in response to the sensed ventricular depolarizations. Responsive to detecting the fast ventricular rate, at least one stimulus pulse is delivered to atrial tissue within the associated refractory period of the ventricle but outside of an associated refractory period of the stimulated atrial tissue. A ventricular response to the atrial tissue stimulus pulse is determined, and the cardiac event is discriminated based on the ventricular response to the atrial tissue stimulus pulse.

Abstract: An apparatus and method to discriminate cardiac events by sensing atrial and ventricular depolarizations having associated refractory periods thereafter. A fast ventricular rate is detected in response to the sensed ventricular depolarizations. Responsive to detecting the fast ventricular rate, at least one stimulus pulse is delivered to atrial tissue within the associated refractory period of the ventricle but outside of an associated refractory period of the stimulated atrial tissue. A ventricular response to the atrial tissue stimulus pulse is determined, and the cardiac event is discriminated based on the ventricular response to the atrial tissue stimulus pulse.

Abstract: Detecting patterns in sensed implantable medical device (IMD) data is described. One implementation involves an IMD that includes a data-driven pattern detection network embodied on the IMD to detect a pattern from sensed patient data. The IMD also includes one or more algorithms embodied on the IMD to utilize the pattern to effect patient therapy.

Abstract: A method for identifying a susceptibility of a subject to atrial-rhythm disturbances includes a) placing a plurality of sensors on the subject to measure a physiologic signal of the subject, and b) recording the physiologic signal from the sensor. The physiologic signal includes an atrial electrical activity of the subject. The method includes c) determining a beat-to-beat variability in the atrial electrical activity of the subject. The beat-to-beat variability includes alternans of electrocardiographic waveforms of a predetermined number of a sequence of heart beats. The method includes d) determining a susceptibility to atrial-rhythm disturbances of the subject using the beat-to-beat variability in the atrial electrical activity determined in step c), and e) generating a report of the susceptibility to atrial-rhythm disturbances of the subject.

Abstract: An implantable medical device controls an anti-tachyarrhythmia therapy by detecting a tachyarrhythmia episode from a cardiac signal and analyzing the detected tachyarrhythmia episode in a tachyarrhythmia detection and analysis process to determine whether the anti-tachyarrhythmia therapy needs to be delivered. The tachyarrhythmia detection and classification process includes detection of inhibitory events each indicating that the tachyarrhythmia episode is of a type not to be treated by the anti-tachyarrhythmia therapy or that the tachyarrhythmia episode is not sustaining. The detection of each of the inhibitory events causes the tachyarrhythmia detection and classification process to be restarted or extended, or the delivery of the anti-tachyarrhythmia therapy to be withheld.

Abstract: Techniques are provided for use by implantable medical devices for controlling ventricular pacing using a multi-pole left ventricular (LV) lead. In one example, a single “V sense” test is performed to determine intrinsic interventricular conduction time delays (?n) between the RV electrode and each of the LV electrodes of the multi-pole lead. Likewise, a single “RV pace” test is performed to determine paced interventricular conduction time delays (IVCD_RLn) between the RV electrode and each of the LV electrodes. A set of “LV pace” tests is then performed to determine paced interventricular conduction time delays (IVCD_LRn) between individual LV electrodes and the RV electrode. Optimal or preferred interventricular pacing delays are determined using the intrinsic interventricular conduction delay (?n) values and a set of interventricular correction terms (?n) determined from the results of the RV pace test and the set of LV pace tests. With these techniques, overall test time can be reduced.

Abstract: Techniques for determining whether a lead related condition exists based on analysis of a cardiac electrical signal associated with a non-sustained tachyarrhythmia (NST) are described. In some examples, the techniques include determining the duration of intervals between consecutive cardiac events, e.g., R-R intervals, during an NST. The techniques may further include determining one or more metrics based on the durations of the intervals during the NST. Examples of metrics include an average, a minimum, a maximum, a range, a median, a mode, or a mean. A lead related condition is identified based on the values of the one or more metrics, e.g., by comparison to respective thresholds. In some examples, an alert is provided or a therapy modification is suggested if a lead related condition is identified.