Abstract: Neurostimulation is delivered to one or more predetermined locations on or within a patient in order to treat effects of sleep apnea by modulating autonomic nervous activity. Delivery of neurostimulation at predetermined locations can decrease sympathetic nervous activity and/or increase parasympathetic nervous activity, countering the increased intrinsic sympathetic activity associated with apnea-arousal cycles. In some embodiments, neurostimulation is delivered to the spinal cord of the patient via an implanted electrode. In other embodiments, neurostimulation is delivered transcutaneously to the spinal cord or other locations via electrodes located on the surface of the patient. In some embodiments, delivery of neurostimulation is initiated or modified in response to detection of apneas.

Abstract: A hemodynamic status of a patient is determined in an implanted medical device (IMD) by observing a perturbation of the patient's heart, measuring heart rate turbulence resulting from the perturbation, and quantifying the heart rate turbulence to determine the hemodynamic status. The perturbation may be naturally-occurring, or may be generated by the implantable medical device. The patient's response to heart rate turbulence may also be used to provide a response to the patient, such as providing an alarm and/or administering a therapy. Heart rate turbulence may also be used to tune and/or optimize a device parameter such as A-V or V-V pacing intervals.

Abstract: The invention provides techniques for delivering anti-tachycardia pacing therapies to a heart. A medical device for providing anti-tachycardia therapy consistent with the invention may include two or more electrodes located proximate to or within the ventricles and/or two or more electrodes located proximate to or within the atria of a heart for treating ventricular and/or atrial tachycardias. At least some of the pulses within a sequence of pulses of a selected therapy may be delivered via each of the two or more electrodes. The timing of the delivery of these pulses by a particular electrode may be based on a programmed cycle length between consecutive pulses within the sequence and delay periods that are programmed for each electrode for each of these pulses. Thus, different electrodes may deliver the same pulse within a sequence at different times, increasing the effectiveness of anti-tachycardia pacing therapies.

Abstract: An implantable device is described that collects and aggregates data from non-implanted medical devices external from a body of a patient. The device may also collect and aggregate data from medical devices implanted within the body. The implantable device includes a wireless transceiver to acquire physiological data from the external medical devices, and a storage medium to store the physiological data. A processor retrieves the physiological data and communicates the physiological data to a remote patient management system. The device may collect the physiologic data from the various external data sources, possibly over an extended period of time, and stores the data for subsequent upload to a common patient management system. In addition, the implantable device may collect physiological data from other medical devices implanted within the patient. In this manner, the device provides a central point for collection and aggregation of physiological data relating to the patient.

Abstract: Methods and devices for determining optimal Atrial to Ventricular (AV) pacing intervals and Ventricular to Ventricular (VV) delay intervals in order to optimize cardiac output. Impedance, preferably sub-threshold impedance, is measured across the heart at selected cardiac cycle times as a measure of chamber expansion or contraction. One embodiment measures impedance over a long AV interval to obtain the minimum impedance, indicative of maximum ventricular expansion, in order to set the AV interval. Another embodiment measures impedance change over a cycle and varies the AV pace interval in a binary search to converge on the AV interval causing maximum impedance change indicative of maximum ventricular output. Another method varies the right ventricle to left ventricle (VV) interval to converge on an impedance maximum indicative of minimum cardiac volume at end systole. Another embodiment varies the VV interval to maximize impedance change.

Abstract: A device and method to detect slow ventricular tachycardia, deliver anti-tachycardia pacing therapies, and delay a scheduled shock therapy if the ventricular tachycardia is not terminated or accelerated. Preferably, a shock therapy is delayed after verifying hemodynamic stability based on a hemodynamic sensor. After a shock is delayed, the device operates in a high alert mode for redetecting an accelerated tachycardia. Anti-tachycardia pacing therapies are repeated during the shock delay. A number of conditions can trigger delivery of the delayed shock therapy including a specified period of elapsed time; determination that the patient is likely to be asleep; detection of myocardial ischemia; detection of compromised hemodynamics, or detection of a substantially prone position or sudden change in position.

Abstract: An apparatus and method for treating sleep apnea includes a control unit in electrical communication with a lead. The control unit is capable of outputting a sleep apnea interruption pulse to stimulate at least one of a phrenic nerve and a diaphragm. Specifically, an implanted medical device (IMD) such as an ICD or a pacemaker paces the heart and a mode switch algorithm changes the pacing output to stimulate at least one of a phrenic nerve and diaphragm when sleep apnea is detected by the control unit. The method includes determining if the patient is experiencing sleep apnea and outputting a sleep apnea interruption pulse to the at least one of a phrenic nerve and a diaphragm. The control unit may be incorporated with the IMD. In another embodiment, the control unit may be in wireless communication with the IMD and positioned outside a patient's body.