Abstract: The extended AV interval of an auto intrinsic conduction search of an implantable cardiac stimulation device has premature atrial contraction protection. A timer times a base AV interval and the extended AV interval. If the heart is paced with the extended AV interval and a premature atrial contraction is detected, the extended AV interval is maintained. Once a predetermined number of consecutive premature atrial contractions are detected, the extended AV interval is reset to the base AV interval.

Abstract: Disclosed herein is a slittable delivery device for the delivery of a cardiac surgical device. The delivery device includes a hub and a shaft integrated into the hub. The shaft forms at least a segment of the circumferential surface of the hub. The delivery device may also include a hemostasis valve contained substantially within the hub and a cap on a proximal end of the hub. The cap may include an opening in the cap extending radially outward from a point near a radial center of the cap through a circumferential edge of the cap.

Abstract: Telemetry data from an IMD are routinely extracted in order to perform a full prognosis of a patient's condition and to alter the IMD therapy programming if necessary. Typically, while the IMD is inside of the patient, it periodically or continuously collects and stores data into its memory. These stored data can then be extracted by a physician to an external device for further analysis. In addition to the stored telemetry data, the physician may also want to collect real-time telemetry data such as real-time IEGM data or other physiological data while the patient is in the physician's office. However, transmitting telemetry data can consume a high level of power and shorten the battery life of the IMD if not properly managed. Thus, it is advantageous to have built-in features to minimize the possibility the IMD is not transmitting and/or receiving data while it is not being monitored and/or used by the physician for a predetermined amount of time.

Abstract: An implantable lead includes a lead body, having a distal end and a proximal end, configured to be implanted in a patient. An electrode assembly is provided at the distal end of the lead body, wherein the electrode assembly includes an electrode that is configured to deliver stimulating pulses. The electrode extends between a base and a tip at a distal end of the electrode. A shielding member is provided on the electrode assembly and is positioned to cover at least a portion of the electrode to electrically shield the electrode from RF fields. Optionally, the shielding member may include a shielding conductor that wraps about and extends longitudinally along a length of the electrode from the base to the tip. The shielding conductor may extend from the proximal end of the lead body at least to the distal end of the lead body.

Abstract: A medical device detects certain patient activity based on a programmable activity threshold and determines the duration of detected activity. The activity threshold may be optimized by obtaining first and second duration measurements for at least one of a first activity session and second activity session. The first duration measurement is based on the activity threshold, while the second duration measurement is based on actual start and stop of the activity session. An adjustment of the activity threshold is suggested based on a correspondence between the first duration measurement and the second duration measurement of the first activity session, or a correspondence between the first duration measurement and the second duration measurement of the second activity session. One of the first and second activities is non-significant activity expected to be undetected by the device, while the other of the two activities is low-level activity expected to be detected by the device.

Abstract: A method of manufacturing a braid-reinforced peelable tubular body is disclosed herein. In one embodiment, the method includes: providing a braided tubular body; forming at least one longitudinally extending slit in tho braided tubular body, resulting in a longitudinally slit braided tubular body, the at least one longitudinally extending slit including slit edges and a severed braid layer of the braided tubular body; placing the longitudinally slit braided tubular body on a mandrel; placing a heat shrink tube about the longitudinally slit braided tubular body; subjecting the heat shrink tube and longitudinally slit braided tubular body to bonding conditions, such as, for example, reflow, laser bonding, thermoforming, etc., thereby causing the slit edges to be joined to each other and resulting in a braid-reinforced peelable tubular body; and removing the braid-reinforced peelable tubular body from the mandrel.

Abstract: An exemplary method includes accessing cardiac information acquired via a catheter located at various positions in a venous network of a heart of a patient where the cardiac information comprises position information, electrical information and mechanical information; mapping local electrical activation times to anatomic positions to generate an electrical activation time map; mapping local mechanical activation times to anatomic positions to generate a mechanical activation time map; generating an electromechanical delay map by subtracting local electrical activation times from corresponding local mechanical activation times; and rendering at least the electromechanical delay map to a display. Various other methods, devices, systems, etc., are also disclosed.

Abstract: A Fast Fourier Transform (FFT) converts time-varying event waveforms into the frequency domain waveforms to thereby decompose the events into their spectral components, which are analyzed to distinguish R-waves from T-waves. In some embodiments, the FFT is only activated if a ventricular tachyarrhythmia is already indicated. For example, an initial ventricular rate may be derived from a ventricular IEGM based on all events detected therein. The initial ventricular rate is compared against one or more thresholds representative of ventricular tachycardia (VT) and/or ventricular fibrillation (VF) to determine if VT/VF is indicated. If so, the FFT is activated to distinguish R-waves from T-waves and, in particular, to detect and eliminate T-wave oversensing. Then, the ventricular rate is re-determined based only on the rate of true R-waves. Therapy is delivered if VT/VF is still detected.

Abstract: In one embodiment, an implantable stimulation apparatus includes a vagal nerve stimulator configured to generate electrical pulses below a cardiac threshold of a heart, and an electrode coupled to the vagal nerve stimulator which is configured to transmit the electrical pulses below the cardiac threshold, to a vagal nerve so as to inhibit injury resulting from an ischemia and/or reduce injury resulting from an ischemia. In another embodiment, an implantable stimulation apparatus includes a vagal nerve stimulator configured to generate electrical pulses below a cardiac threshold, and includes an electrode, which is coupled to the vagal nerve stimulator and configured transmit electrical pulses to a vagal nerve so as to reduce a defibrillation threshold of the heart.

Abstract: Various techniques are described for preventing pacemaker mediated tachycardia (PMT) within biventricular pacing systems and for detecting and terminating PMT should it nevertheless arise. In a first prevention technique, refractory periods applied to the atrial channel are synchronized to begin with a second of a pair of ventricular pacing pulses to more effectively prevent T-wave oversensing on the atrial channel. In a second prevention technique, the sensitivity of the atrial channel is reduced during T-waves also to prevent T-wave oversensing. In a third prevention technique, template matching is performed on the ventricular channels to prevent T-wave oversensing. In a fourth prevention technique, T-wave detection windows are applied to both the ventricular and atrial channels subsequent to any paced or sensed events.

Abstract: An exemplary method includes delivering a pace using an electrode positioned on the lateral wall of the left ventricle of a heart, sensing the pace using an electrode positioned in the right ventricle of the heart, determining a left to right directional conduction time (TLR), delivering a pace using an electrode positioned in the right ventricle of the heart, sensing the pace using an electrode positioned on the lateral wall of the left ventricle of the heart, determining a right to left directional conduction time (TRL), calculating a site-to-site offset (VVATP) for multi-site anti-tachycardia pacing based on the left to right directional conduction time and the right to left directional conduction time and instructing an implantable device to deliver multi-site anti-tachycardia pacing using the site-to-site offset (VVATP). Other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: A method and apparatus for treating an arrhythmia is provided. The method includes the steps of: (a) sensing at least one electrical signal from the patient's heart; (b) calculating a frequency spectrum of each electrical signal; (c) calculating a center frequency for each frequency spectrum; and (d) selecting an electro-therapy for delivery to the patient's heart based on the center frequency. The electro-therapy can be a pre-programmed anti-tachycardia pacing (ATP) therapy, a shock therapy, or no therapy at all. The method is performed through the use of an implantable cardioverter defibrillator (ICD). Also provided is a method of determining the optimal location to deliver the electro-therapy.

Abstract: Techniques are provided for use by a pacemaker or other implantable medical device for detecting and tracking trends in cardiopulmonary fluid transfer rates—such as heart-to-lung fluid perfusion rates and lung-to-lymphatic system fluid excretion rates—and for detecting heart failure, dyspnea or other cardiopulmonary conditions. In one example, the device periodically measures transthoracic admittance values. A first exponential time-constant (k1) is determined using curve-fitting from admittance values obtained while the patient is in a sleep posture. Time-constant k1 is representative of the fluid perfusion rate. A second exponential time-constant (k2) is determined based on admittance values obtained while the patient is standing/walking/sitting. The second exponential time-constant (k2) is representative of the fluid excretion rate from the lungs.

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 system and method of adjusting therapy delivery in an implantable cardiac stimulation device including establishing a plurality of setting combinations for at least two variable parameters of the implantable cardiac stimulation device affecting delivery of therapy. At least one aspect of a patient's physiologic performance is evaluated under individual ones of the plurality of setting combinations selected such that at least one of the two variable parameters vary among the plurality of combinations. A setting combination providing more optimal patient physiologic performance is programmed for future delivery of therapy. An external device can provide measurements indicative of cardiac performance. Measurements of cardiac performance can also be obtained by an implantable device.

Abstract: An implantable cardiac electrotherapy lead is disclosed herein. In one embodiment, the lead includes a tubular body having a distal end with a first soft resilient member. The member extends or is extendable from the distal end radially outward relative to a longitudinal axis of the tubular body.

Abstract: A morphology discrimination scheme extracts shape characteristics from cardiac signals and identifies an associated cardiac condition based on the shape characteristics. For example, internal data structures may be updated to match the shape characteristics of a known condition (e.g., a patient's normal sinus rhythm). Similarly acquired shape characteristics obtained in conjunction with a later event (e.g., QRS complexes acquired during a tachycardia episode) may be compared with the previously stored shape characteristics to characterize the later event. In some aspects the shape characteristics relate to inflection points of cardiac signals.

Abstract: An implantable cardiac device is programmed to detect and classify premature atrial contractions (PACs) and administer responsive pacing therapy. The responsive pacing therapy is in the form of an atrial extrastimulus, which is intended to preempt initiation of a reentrant tachycardia. The atrial extrastimulus is timed to occur late enough after a PAC to ensure atrial capture, but early enough that the resulting atrial depolarization does not conduct through the AV node to the ventricles if the PAC has already done so. If both of these criteria cannot be met, the device may be configured to inhibit the atrial extrastimulus.

Abstract: Techniques are provided for use in controlling rate-adaptive pacing within implantable medical devices such as pacemakers or implantable cardioverter-defibrillators (ICDs). In one example, a force-frequency relationship is determined for the heart of the patient, which is representative of the relationship between cardiac stimulation frequency and myocardial contractile force. To this end, various parameters are detected for use as surrogates for contractile force, including selected systolic pressure parameters and cardiogenic impedance parameters. Rate-adaptive pacing is then controlled based on the detected force-frequency relationship to, for example, deactivate rate-adaptive pacing if the slope and/or abscissa of the force-frequency relationship indicates significant contractility dysfunction within the patient. In other examples, rather than deactivating rate-adaptive pacing, control parameters are adjusted to render the rate-adaptive pacing less aggressive.

Abstract: An implantable therapy system including implantable stimulation and control components. The implantable components operate under a set of variable parameters that can be adjusted for improved performance for an individual patient. The implantable components are adapted to self-evaluate the patients physiologic performance and autonomously adjust an existing set of parameters to improve performance throughout an implantation period without requiring intervention of a clinician, for example with a physicians programmer. The implantable components can compare a patient's exhibited activity to a desired template of that activity to determine when adjustments are indicated. The template can be based on observations of one or more third parties exhibiting normal activity. The implantable components can adjust the operating parameters to improve synchrony of multiple heart chambers and/or to increase a peak contractility.