Abstract: A device, such as an implantable cardiac device, and method for switching between arrhythmia prevention modes is disclosed. The method includes monitoring an electrocardiogram (EGM) of the heart, determining whether the heart is in a normal sinus rhythm or in an abnormal rhythm, delivering pacing pulses at a first rate to either an atrium or a ventricle when the heart is in a normal sinus rhythm, and delivering pacing pulses to a ventricle at a second rate when the heart is in an abnormal rhythm, such as an atrial arrhythmia. The first rate is selected to minimize the occurrence of premature ventricular contractions, and the second rate is selected to both minimize the occurrence of premature ventricular contractions and minimize the occurrence of premature conducted beats.

Abstract: Techniques are provided for detecting atrial events that might be hidden due to the operation of a post-ventricular atrial blanking (PVAB) interval or other atrial channel blanking interval. In one example, candidate atrial events are identified within signals occurring during the PVAB interval. Then, a determination is made as to whether the candidate atrial event is a true atrial event based on a comparison of characteristics of the candidate atrial event with characteristics of prior known atrial events within the patient. By comparing the characteristics of the “hidden” event with the characteristics of prior known atrial events within the patient, a quick and accurate determination can be made whether the event should be counted as a P-wave. In this manner, hidden atrial arrhythmias can be detected and mode switch oscillations can be reduced or eliminated.

Abstract: An implantable medical device includes a lead configured to be located proximate to the left ventricle (LV) of the heart, the lead including multiple LV electrodes to sense cardiac activity at multiple LV sensing sites. The a detection module to detect an arrhythmia that represents at least one of a tachycardia and fibrillation based at least in part on the cardiac activity sensed at the multiple LV sensing sites. The ATP therapy module to identify at least one of an ATP configuration or an ATP therapy site based on the cardiac sensed activity at the LV sensing sites, the ATP therapy module to control delivery of antitachycardia pacing (ATP) therapy at the ATP therapy site.

Abstract: A method of monitoring progression of cardiac disease includes applying stimulus pulses to the heart and sensing electrophysiological responses of the heart at a plurality of different monitoring locations of the heart. The method also includes comparing a previously and subsequently sensed electrophysiological responses that are sensed near a first location of the monitoring locations and comparing previously and subsequently sensed electrophysiological responses that are sensed near a second location of the monitoring locations. The method further includes identifying a change in progression of cardiac disease of the heart based on a difference between the previously and subsequently sensed electrophysiological responses at the first location and based on a difference between the previously and subsequently sensed electrophysiological responses at the second location.

Abstract: Techniques are provided for detecting a clinically-significant pulmonary fluid accumulation within a patient using a pacemaker or other implantable medical device. Briefly, the device detects left atrial pressure (LAP) within the patient and tracks changes in the LAP values over time that are indicative of possible pulmonary fluid accumulation within the patient. The device determines whether the changes in LAP values are sufficiently elevated and prolonged to warrant clinical intervention using, e.g., a predictor model-based technique. If the fluid accumulation is clinically significant, the device then generates warning signals, records diagnostics, controls therapy and/or titrates diuretics. False positive detections of pulmonary edema due to transients in LAP are avoided with this technique. Pulmonary artery pressure (PAP)-based techniques are also described.

Abstract: A composite lead body includes a rigid polymer material, such as silicone-polyurethane co-polymers, in a proximal portion of the lead body and a flexible polymer material, such as silicone, in a distal portion of the lead body. The flexible polymer material is molded in-situ about the end of the rigid polymer material, which is pre-formed, forming a junction at which the two polymers are bonded together, preferably in an interdigitated manner. The end of the rigid polymer is treated with a primer in order to facilitate the formation of a strong bond between the polymers. The molding process, advantageously, provides substantial control over the final shape of the molded polymer, inhibiting the formation of discontinuities in the shape of the lead body.

Abstract: Techniques are provided for use with implantable cardiac stimulation devices equipped for multi-site left ventricular (MSLV) cardiac pacing. Briefly, intraventricular and interventricular conduction delays are detected for paced cardiac events. Maximum pacing time delays are determined for use with MSLV pacing where the maximum pacing time delays are set based on the conduction delays to values sufficient to avoid capture problems due to wavefront propagation, such as fusion or lack of capture. MSLV pacing delays are then set to values no greater than the maximum pacing delays and cardiac resynchronization therapy (CRT) is delivered using the MSLV pacing delays. In an example where an optimal interventricular pacing delay (VV) is determined in advance using intracardiac electrogram-based or hemodynamic-based optimization techniques, the optimal value for VV can be used as a limiting factor when determining the maximum MSLV pacing time delays.

Abstract: Various techniques are provided for assessing the reliability of left atrial pressure (LAP) estimates made by an implantable medical device based on impedance values or related electrical values. In one example, various cardioelectric and cardiomechanical parameters are used to corroborate LAP estimation in circumstances where the LAP estimates deviate from an acceptable, satisfactory or otherwise healthy range. The cardioelectric parameters include, e.g.: ST elevation; heart rate (HR); heart rate variability (HRV); T-wave alternans (TWA); QRS waveform parameters; P-wave duration; evoked response (ER) parameters; and intrinsic PV/AV/VV conduction delays. The cardiomechanical parameters include, e.g.: heart rate turbulence (HRT); cardiogenic impedance signals; heart sounds; and non-LAP blood pressure measurements, such as aortic pressure measurements.

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: Exemplary systems, devices, and methods pertaining to cardiac related therapy and particularly to interferential cardiac preconditioning and depolarization are described. A cardiac arrhythmia is detected from electrogram data sensed from a patient's heart and a region of the heart affected by the cardiac arrhythmia is determined. The affected region is interferentially energized by multiple cycles of two concurrently delivered alternating currents which are offset in frequency.

Abstract: In fabricating a header assembly of an implantable medical device, one end of a bore contact wire attached to a connector block is keyed with one guiding channel at an upper region of a feedthru adapter and through the adapter to its undersurface. An opposite end is bent into conformance with an orientation channel on the adaptor undersurface. A tip end of a feedthru wire connected to electronic circuitry of the medical device and projecting out of a casing mounting surface is bent for alignment with the orientation channel so end portions of the feedthru wire and bore contact wire are in end to end engagement, then welded together. A plastic header is molded to encapsulate the adapter, connector block, and bore contact wire and, when solidified, has an undersurface for engagement on the casing and an elongated receptacle aligned with a connector block bore to receive the lead.

Abstract: A first lead provides therapeutic stimulation to the heart and includes a first mechanical sensor that measures physical contraction and relaxation of the heart. A controller induces delivery of therapeutic stimulation via the first lead. The controller receives signals from the first mechanical sensor indicative of the contraction and relaxation; develops a template signal that corresponds to the contraction and relaxation; and uses the template signal to modify the delivery of therapeutic stimulations. In another arrangement, a second lead, with a second mechanical sensor also provides signals to the controller indicative of contraction and relaxation. The first mechanical sensor is adapted to be positioned at the interventricular septal region of the heart, and the second mechanical sensor is adapted to be positioned in the lateral region of the left ventricle. The controller processes the signals from the first mechanical sensor and the second mechanical sensor to develop a dysynchrony index.

Abstract: A method of determining pacing therapy for an individual patient including determining representative electromechanical physiologic characteristics for a plurality of normal patients having a range of anatomical dimensions and developing a plurality of normal templates. Each template indicates the representative electromechanical physiologic characteristics of a group of normal patients having similar anatomical dimensions.

Abstract: Systems and methods are provided wherein intracardiac electrogram (IEGM) signals are used to determine a set of preliminary optimized atrioventricular (AV/PV) and interventricular (VV) pacing delays. In one example, the preliminary optimized AV/VV pacing delays are used as a starting point for further optimization based on impedance signals such as impedance signals detected between a superior vena cava (SVC) coil electrode and a device housing electrode, which are influenced by changes in stroke volume within the patient. Ventricular pacing is thereafter delivered using the AV/VV pacing delays optimized via impedance. In another example, parameters derived from IEGM signals are used to limit the scope of an impedance-based optimization search to reduce the number of pacing tests needed during impedance-based optimization. Biventricular and multi-site left ventricular (MSLV) examples are described.

Abstract: Disclosed herein is an implantable pulse generator feedthru configured to make generally planar electrical contact with an electrical component housed within a can of an implantable pulse generator. The feedthru may include a feedthru housing including a header side and a can side, a core within the feedthru housing, a generally planar electrically conductive interface adjacent the can side, and a feedthru wire extending through the core. The feedthru wire may include an interface end and a header end, wherein the header end extends from the header side and the interface end is at least one of generally flush with the generally planar interface and generally recessed relative to the generally planar interface.

Abstract: An exemplary method includes use of a multielectrode device that can help position a cardiac stimulation lead to an optimal site in the heart based at least in part on cardiac motion information acquired via the multielectrode device and one or more pairs of current delivery electrodes that establish potential fields (e.g., for use as a coordinate system). An exemplary mutlielectrode device may be a multielectrode catheter or a multifilar, electrode-bearing guidewire. Various other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: A feedthrough assembly for use with implantable medical devices having a shield structure, the feedthrough assembly engaging with the remainder of the associated implantable medical device to form a seal with the medical device to inhibit unwanted gas, liquid, or solid exchange into or from the device. One or more feedthrough wires extend through the feedthrough assembly to facilitate transceiving of the electrical signals with one or more implantable patient leads. The feedthrough assembly is connected to a mechanical support which houses one or more filtering capacitors that are configured to filter and remove undesired frequencies from the electrical signals received via the feedthrough wires before the signals reach the electrical circuitry inside the implantable medical device.

Abstract: Techniques are provided for use with implantable medical devices such as pacemakers for optimizing interventricular (VV) pacing delays for use with cardiac resynchronization therapy (CRT). In one example, ventricular electrical depolarization events are detected within a patient in which the device is implanted. The onset of isovolumic ventricular mechanical contraction is also detected based on cardiomechanical signals detected by the device, such as cardiogenic impedance (Z) signals, S1 heart sounds or left atrial pressure (LAP) signals. Then, an electromechanical time delay (T_QtoVC) between ventricular electrical depolarization and the onset of isovolumic ventricular mechanical contraction is determined. VV pacing delays are set to minimize the time delay to the onset of isovolumic ventricular mechanical contraction. Various techniques for identifying the onset of isovolumic ventricular contraction based on Z, S1 or LAP or other cardiomechanical signals are described.

Abstract: A system with an implantable cardiac stimulation device having an implantable stimulation generator, at least one implantable lead adapted for connection to the implantable stimulation generator and further adapted for at least one of sensing physiologic activity and delivery of therapy, memory, and a controller in communication with the memory and with the at least one implantable lead and stimulation generator. The controller is configured to automatically evaluate a patient's physiologic status and selectively induce delivery of therapeutic stimulation under variable timing parameters. The system also has a measurement system adapted to measure at least one of strain and velocity of myocardial tissue and is adapted to evaluate strain and/or velocity measures and adjust the variable timing parameters of the implantable stimulation device to increase mechanical synchrony of the myocardial tissue.

Abstract: Implantable systems, and methods for use therein, for monitoring for mitral valve regurgitation (MR) are provided. An electrogram (EGM) signal and a corresponding pressure signal are obtained, where the EGM signal is representative of electrical functioning of the patient's heart during a plurality of cardiac cycles, and the corresponding pressure signal is representative of pressure within the left atrium the patient's heart during the cardiac cycles. Windows of the pressure signal are defined, based on events detected in the EGM signal, and measurements from the windows are used to monitor for MR.