Abstract: A lead includes a lead body and an electrode disposed proximate a distal end of the lead body. A retaining member is disposed proximate the distal end of the lead and adapted to retain the electrode proximate an interatrial septum when the retaining member is located on a left atrial side of the interatrial septum.

Abstract: A method and system for delivering anti-tachycardia pacing (ATP) is disclosed. During delivery of an ATP burst, an implantable cardiac rhythm management device is programmed to sense evoked responses and determine whether or not the ATP burst has entrained the heart by counting the number of successive pacing pulses achieving capture. This information may then be used by the device to adjust the manner in which the ATP therapy is delivered.

Abstract: A method for titrating a drug to provide a medical therapy to a patient. The method includes the steps of providing an implantable medical device having a controller, providing one or more implantable sensors configured to sense physical parameters of the patient and configured to transmit signals to the controller. The method further includes the step of receiving signals from the one or more sensors at the controller. The method additionally includes processing the received signals to determine at least two cardiopulmonary characteristics of the patient. The method also includes determining a composite index based on the at least two cardiopulmonary characteristics. In addition, the method includes generating a signal based on the composite index. Medical device systems are also disclosed.

Abstract: Systems and methods for monitoring lung edema fluid status, such as monitoring the presence or absence of pulmonary edema, in a subject using information about responsive acoustic energy echoes from a lung are described. The system comprises, among other things, an implantable device including an acoustic transducer configured to emit acoustic energy to a lung and to receive one or more responsive acoustic energy echoes from a lung. In an example, the implantable device includes a cardiac function management device having an acoustic window in a body thereof. In another example, the implantable device includes one or more subcutaneous leads. An implantable or external processor circuit is configured to receive information about the acoustic energy echoes to compute and provide a lung edema fluid status indication; such information may include an increased number or special pattern of acoustic energy echoes received or a decreased time between successively received echoes.

Abstract: An apparatus includes an implantable acoustic viscosity sensor configured to acoustically obtain a viscosity signal indicative of a viscosity of a fluid in contact with the viscosity sensor. A viscosity measurement circuit produces a viscosity measurement from the viscosity signal.

Abstract: A method and apparatus for delivering therapy to treat ventricular tachyarrhythmias is described. A ventricular tachyarrhythmia can be classified into tachycardia or fibrillation zones using a rate criterion so that the tachyarrhythmia can be treated with either anti-tachycardia pacing or shock therapy, respectively. Rate stability and morphology criteria are employed to determine if a tachyarrhythmia in the fibrillation zone is actually monomorphic ventricular tachycardia which can be treated with ATP.

Abstract: Embodiments of the invention are related to implantable devices including movement sensors and related methods for measuring cardiac performance, amongst other things. In an embodiment, the invention includes an implantable electrical stimulation lead. The electrical stimulation lead can include a lead body having a proximal end and a distal end and a sheath defining a central lumen. The lead body can further include an electrical conductor disposed within the central lumen of the sheath. The stimulation lead can further include a stimulation electrode positioned at the distal end of the lead body, the stimulation electrode in electrical communication with the electrical conductor. The electrical stimulation lead can include an flexion sensor coupled to the lead body, the movement sensor configured to generate a signal in response to movement of the lead body. In an embodiment, the invention includes a method of monitoring the condition of a heart failure patient.

Abstract: A system delivers stimulation to volume receptors in the cardiovascular system to induce diuresis in a patient suffering volume overload. The system senses a volume signal indicative of a level of fluid retention in the patient's body and controls the delivery of the stimulation using the volume signal. In various embodiments, the stimulation includes one or more of electrical stimulation, which delivers electrical pulses to the volume receptors, and mechanical stimulation, which physically stretches the volume receptors.

Abstract: An implantable medical device senses a plurality of electrograms from substantially different atrial locations, detects regional depolarizations from the electrograms, and analyzes timing relationships among the regional depolarizations. The timing relationships provide a basis for effective therapy control and/or prognosis of certain cardiac disorders. In one embodiment, an atrial activation sequence is mapped to show the order of occurrences of the regional depolarizations during an atrial depolarization for classifying a detected tachyarrhythmia by its origin. In another embodiment, conduction time between two atrial locations is measured for monitoring the development of an abnormal atrial conditions and/or the effect of a therapy.

Abstract: A method and apparatus permit sensing one or more forces exerted by one or more portions of a heart. A force transducer and displacement sensor are disclosed. A movement of one or more portions of a heart can be translated into one or more signals indicative of force. These signals can be used to provide information such as to diagnose or treat one or more conditions.

Abstract: Systems and methods include sensing whether a shock to a heart is needed, and prior to delivering the shock, causing at least a partial contraction of a musculature in a chest, and delivering the shock while the musculature is at least partially contracted.

Abstract: An implantable medical device senses a plurality of electrograms from substantially different atrial locations, detects regional depolarizations from the electrograms, and analyzes timing relationships among the regional depolarizations. The timing relationships provide a basis for effective therapy control and/or prognosis of certain cardiac disorders. In one embodiment, an atrial activation sequence is mapped to show the order of occurrences of the regional depolarizations during an atrial depolarization for classifying a detected tachyarrhythmia by its origin. In another embodiment, conduction time between two atrial locations is measured for monitoring the development of an abnormal atrial conditions and/or the effect of a therapy.

Abstract: A method and system for delivering anti-tachycardia pacing (ATP) is disclosed. By comparing the time intervals between senses from both ventricles, the origin of a ventricular tachyarrhythmia may be mapped to one or the other of the ventricles. The arrhythmic ventricle may then be paced with either single-ventricle or biventricular ATP pacing.

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: A delivery system and method for delivering a right ventricular lead into a right ventricle includes a delivery device having an inflatable balloon at a distal end. The device is inserted into the venous system, the balloon is inflated and the device is floated along a blood flow path within the venous system through the heart and into the pulmonary artery. The lead is delivered into the right ventricle using the device. In one embodiment, the device is a catheter that facilitates placement of a guide wire into the right ventricle for delivery of the lead. The catheter is then removed and the lead is inserted into the right ventricle over the guide wire.

Abstract: A method involves implantably detecting changes in posture of a patient's body. Baroreflex responses to the posture changes are determined. An autonomic tone of the patient is determined based on the baroreflex responses. Based on the autonomic tone, various patient susceptibilities to disease may be determined, including susceptibilities to heart disease, arrhythmia, and/or sudden cardiac death.

Abstract: An implantable medical device for generating a cardiac pressure-volume loop, the implantable medical device comprising a pulse generator including control circuitry, a first cardiac lead including a proximal end and a distal end and coupled to the pulse generator at the proximal end, a first electrode located at the distal end of the cardiac lead and operatively coupled to the control circuitry, a sound sensor operatively coupled to the control circuitry, and a pressure sensor operatively coupled to the control circuitry, wherein the implantable medical device is adapted for measuring intracardiac impedance. A method of using the implantable medical device to optimize therapy delivered to the heart.

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: A system to measure intracardiac impedance includes implantable electrodes and a medical device. The electrodes sense electrical signals of a heart of a subject. The medical device includes a cardiac signal sensing circuit coupled to the implantable electrodes, an impedance measurement circuit coupled to the same or different implantable electrodes, and a controller circuit coupled to the cardiac signal sensing circuit and the impedance measurement circuit. The cardiac signal sensing circuit provides a sensed cardiac signal. The impedance measurement circuit senses intracardiac impedance between the electrodes to obtain an intracardiac impedance signal. The controller circuit determines cardiac cycles of the subject using the sensed cardiac signal, and detects tachyarrhythmia using cardiac-cycle to cardiac-cycle changes in a plurality of intracardiac impedance parameters obtained from the intracardiac impedance signal.

Abstract: Various embodiments of the present subject matter relate to a method. According to various method embodiments, at least one lead is inserted through a pulmonary artery to securely position at least one electrode within the pulmonary artery. Neural stimulation is applied to a neural stimulation target using the at least one lead in the pulmonary artery. An atrial rhythm management activity, including at least one of capturing atrial tissue using the at least one lead and sensing an intrinsic atrial event, is performed using the at least one lead in the pulmonary artery. Other embodiments are provided herein.