Abstract: A single-pass endocardial lead electrode adapted for implantation in, on or about the heart and for connection to a system for monitoring or stimulating cardiac activity includes a lead body which is adapted for implantation within a single chamber of the heart, or multiple chambers of the heart. The lead includes a first distal end electrode which has a first electrical conducting surface. The lead body also has a second electrode which has a second electrical conducting surface. The first and second electrodes are either passively or actively attached to the wall of the heart. The lead body also includes a curved portion which facilitates the positioning of the second electrode. The main lead body alternatively includes a recess into which an atrial lead body and an active fixation element attached to one end can travel from a recessed position to a position for fixation to the wall of the heart. The lead is attached to a pulse generator for producing pulses to the multiple sites within the heart.

Abstract: A cardiac rhythm management device capable of delivering multiple uni-chamber stimulation pulses to a patient's heart and suitable for verifying capture independently for each uni-chamber stimulation pulse. The uni-chamber capture verification mode of the cardiac rhythm management device may be activated via telemetry or by applying a magnetic field proximate the device. During the capture verification mode, bi-chamber pacing, for example, may precede or follow uni-chamber pacing to allow for pacing support. Also, the energy levels of the pacing stimulus over several beats may be varied, thereby verifying the programmed safety margins.

Abstract: A lead for monitoring or stimulating cardiac activity is provided. The lead is adapted for implantation on or about the heart within the coronary vasculature and for connection to a signal generator. The lead body has one or more electrodes associated therewith. The lead is constructed and arranged so that when it is implanted, the electrodes are housed in the coronary vasculature and urged into intimate contact a vessel wall. A method for implanting the lead into the coronary vasculature is also provided, the method comprising the steps of inserting a stylet into the lead, inserting the lead into the coronary sinus, advancing the lead from the coronary sinus toward the toward the left atrium and into a coronary vein, removing the stylet, and sensing and pacing the heart.

Abstract: A cardiac rhythm management system, such as an implantable cardioverter-defibrillator (ICD), provides atrial anti-tachyarrhythmia therapy, such as a bipolar or unipolar electrical cardioversion countershock, or provides both atrial and ventricular anti-tachyarrhythmia therapy. The atrial and ventricular anti-tachyarrhythmia therapies have independent cardioversion-defibrillation energy levels and other parameters. The system provides an endocardial lead that is convenient to implant for providing anti-tachyarrhythmia therapy. The endocardial lead includes a first supraventricular electrode disposed in the atrium and superior vena cava, and optionally includes a first ventricular electrode and ICD housing electrode.

Abstract: A method for operating a cardiac rhythm management device in which a clinical state vector is computed as a combination of a plurality of parameters related to a patient's heart failure status and compared to a previously computed clinical state vector to determine a clinical trajectory indicative of changes in the patient's heart failure status. Such detected changes in status can be used both as a clinical tool to evaluate treatment and to automatically adjust the operation of the device.

Abstract: A cardiac rhythm management device capable of delivering multiple uni-chamber stimulation pulses to a patient's heart and suitable for verifying capture independently for each uni-chamber stimulation pulse. The uni-chamber capture verification mode of the cardiac rhythm management device may be activated via telemetry or by applying a magnetic field proximate the device. During the capture verification mode, bi-chamber pacing, for example, may precede or follow uni-chamber pacing to allow for pacing support. Also, the energy levels of the pacing stimulus over several beats may be varied, thereby verifying the programmed safety margins.

Abstract: A first electrode is positioned within an artery proximate an implanted intravascular stent. A second electrode is positioned at a separate location relative the position of the first electrode. Electrical energy is then delivered between the first and the second electrodes to produce an electrical field adjacent the implanted intravascular stent. When a intravascular stent is implanted in a coronary artery, the delivery of the electrical energy is coordinated to cardiac cycles detected in sensed cardiac signals, where the delivery of the electrical energy between the first electrode and the second electrode occurs during a predetermined portion of the cardiac cycle.

Abstract: A single-pass endocardial lead electrode adapted for implantation in, on or about the heart and for connection to a system for monitoring or stimulating cardiac activity includes a lead body which is adapted for implantation within a single chamber of the heart, or multiple chambers of the heart. The lead includes a first distal end electrode which has a first electrical conducting surface. The lead body also has a second electrode which has a second electrical conducting surface. The first and second electrodes are either passively or actively attached to the wall of the heart. The lead body also includes a curved portion which facilitates the positioning of the second electrode. The main lead body alternatively includes a recess into which an atrial lead body and an active fixation element attached to one end can travel from a recessed position to a position for fixation to the wall of the heart. The active fixation element can also be moved by turning the terminal pin.

Abstract: A cardiac rhythm management system includes atrial shock timing optimization. Because an atrial tachyarrhythmia, such as atrial fibrillation typically causes significant variability in the ventricular heart rate, resulting in potentially proarrhythmic conditions. The system avoids delivering atrial cardioversion/defibrillation therapy during potentially proarrhythmic conditions because doing so could result in dangerous ventricular arrhythmias. Using Ventricular Rate Regularization (“VRR”) techniques, the system actively stabilizes the ventricular heart rate to obtain less potentially proarrhythmic conditions for delivering the atrial tachyarrhythmia therapy. The intrinsic ventricular heart rate is stabilized at a variable VRR-indicated rate, computed using an infinite impulse response (IIR) filter, and based on the underlying intrinsic ventricular heart rate.

Abstract: A cardiac rhythm management system includes atrial shock timing optimization. Because an atrial tachyarrhythmia, such as atrial fibrillation typically causes significant variability in the ventricular heart rate, resulting in potentially proarrhythmic conditions. The system avoids delivering atrial cardioversion/defibrillation therapy during potentially proarrhythmic conditions because doing so could result in dangerous ventricular arrhythmias. Using Ventricular Rate Regularization (“VRR”) techniques, the system actively stabilizes the ventricular heart rate to obtain less potentially proarrhythmic conditions for delivering the atrial tachyarrhythmia therapy. The intrinsic ventricular heart rate is stabilized at a variable VRR-indicated rate, computed using an infinite impulse response (IIR) filter, and based on the underlying intrinsic ventricular heart rate.

Abstract: A first electrode is positioned within an artery proximate an implanted intravascular stent. A second electrode is positioned at a separate location relative the position of the first electrode. Electrical energy is then delivered between the first and the second electrodes to produce an electrical field adjacent the implanted intravascular stent. When a intravascular stent is implanted in a coronary artery, the delivery of the electrical energy is coordinated to cardiac cycles detected in sensed cardiac signals, where the delivery of the electrical energy between the first electrode and the second electrode occurs during a predetermined portion of the cardiac cycle.

Abstract: A cardiac rhythm management device capable of delivering multiple uni-chamber stimulation pulses to a patient's heart and suitable for verifying capture independently for each uni-chamber stimulation pulse. The uni-chamber capture verification mode of the cardiac rhythm management device may be activated via telemetry or by applying a magnetic field proximate the device. During the capture verification mode, bi-chamber pacing, for example, may precede or follow uni-chamber pacing to allow for pacing support. Also, the energy levels of the pacing stimulus over several beats may be varied, thereby verifying the programmed safety margins.

Abstract: An anti-tachyarrhythmia therapy, such as a countershock is provided, to an atrium needing treatment, but its delivery is delayed for a programmable period of time following an indication of susceptibility to ventricular tachyarrhythmia (VT). This reduces the risk of reinducing VT during a period in which the heart is abnormally metabolically vulnerable to VT, including ventricular fibrillation (VF). The delay time may be independently programmed for different indications of VT, and may be synchronized to and delayed from the R-wave. The delay time may be adjusted, such as to exceed one second, or even to exceed several hours, in order to accommodate the metabolic abnormal susceptibility of the particular patient in the wide range of patients needing treatment of atrial tachyarrhythmias.

Abstract: An electric power monitoring system includes a source monitor for measuring momentary power output of an electric source supplying electric power to a power distribution system having at least one electric load. The momentary power output is compared with a reference load capability for the electric source to determine the ability of the electric source to support additional load, and load capability data is transmitted based on the load capability. At least one load control receives the transmitted load capability data and controls the supply of power to the at least one corresponding electric load based on the load capability data.

Abstract: A first electrode is positioned within an artery proximate an implanted intravascular stent. A second electrode is positioned at a separate location relative the position of the first electrode. Electrical energy is then delivered between the first and the second electrodes to produce an electrical field adjacent the implanted intravascular stent. When a intravascular stent is implanted in a coronary artery, the delivery of the electrical energy is coordinated to cardiac cycles detected in sensed cardiac signals, where the delivery of the electrical energy between the first electrode and the second electrode occurs during a predetermined portion of the cardiac cycle.

Abstract: A first electrode is positioned within an artery proximate an implanted intravascular stent. A second electrode is positioned at a separate location relative the position of the first electrode. Electrical energy is then delivered between the first and the second electrodes to produce an electrical field adjacent the implanted intravascular stent. When a intravascular stent is implanted in a coronary artery, the delivery of the electrical energy is coordinated to cardiac cycles detected in sensed cardiac signals, where the delivery of the electrical energy between the first electrode and the second electrode occurs during a predetermined portion of the cardiac cycle.

Abstract: Anti-tachyarrhythmia therapy, such as a countershock, is provided to an atrium needing treatment, but delays its delivery for a programmable period of time following an indication of susceptibility to ventricular tachyarrhythmia (VT). This reduces the risk of reinducing VT during a period in which the heart is abnormally metabolically vulnerable to VT, including ventricular fibrillation (VF). The delay time may be independently programmed for different indications of VT, and may be synchronized to and delayed from the R-wave. The delay time may be adjusted, such as to exceed one second, or even to exceed several hours, in order to accommodate the metabolic abnormal susceptibility of the particular patient in the wide range of patients needing treatment of atrial tachyarrhythmias.

Abstract: The invention provides anti-tachyarrhythmia therapy, such as a countershock, to an atrium needing treatment, but delays its delivery for a programmable period of time following an indication of susceptibility to ventricular tachyarrhythmia (VT). This reduces the risk of reinducing VT during a period in which the heart is abnormally metabolically vulnerable to VT, including ventricular fibrillation (VF). The delay time may be independently programmed for different indications of VT, and may be synchronized to and delayed from the R-wave. The delay time may be adjusted, such as to exceed one second, or even to exceed several hours, in order to accommodate the metabolic abnormal susceptibility of the particular patient in the wide range of patients needing treatment of atrial tachyarrhythmias.

Abstract: A battery system and method of manufacture in which at least two batteries, having different chemistries, are integrated into a common housing. The battery system has a unitary housing having at least two chambers, in which each pair of adjacent chambers share a common wall. Each chamber contains one battery, and at least one battery has a different chemical composition than the remaining batteries.

Abstract: A single-pass endocardial lead electrode adapted for implantation in, on or about the heart and for connection to a system for monitoring or stimulating cardiac activity includes a lead body which is adapted for implantation within a single chamber of the heart, or multiple chambers of the heart. The lead includes a first distal end electrode which has a first electrical conducting surface. The lead body also has a second electrode which has a second electrical conducting surface. The first and second electrodes are either passively or actively attached to the wall of the heart. The lead body also includes a curved portion which facilitates the positioning of the second electrode. The main lead body alternatively includes a recess into which an atrial lead body and an active fixation element attached to one end can travel from a recessed position to a position for fixation to the wall of the heart. The active fixation element can also be moved by turning the terminal pin.