Abstract: The present invention provides methods and systems for tachyarrhythmia therapy involving pacing the heart to prior to the application of a cardioversion/defibrillation shock. One or more pace pulses are delivered to the arrhythmic chamber or chambers. The pace pulses may be delivered to the heart at an adaptable rate selected to organize the electrical activity of the heart. If the pace pulses produce capture, cardioversion/defibrillation stimulation is delivered.

Abstract: Ultrasonic dissection instruments and methods provide for fluid delivery during subcutaneous dissection. An ultrasonic dissection tool includes a handle, a transducer and a dissecting member. The dissecting member extends from the distal end of the transducer, and a fluid channel system extends from at least the proximal end to the distal end of the dissecting member. The fluid channel system terminates in a port system. The port system may include one or more apertures, one or more channels, and be adapted to transport fluids such as, for example, irrigation fluids, fluids having analgesics, antibiotics, and combinations of fluids and agents.

Abstract: Cardiac methods and devices that separate signals using at least two composite signals acquired at least at two input impedances. A target source impedance may be selected, and a cardiac signal may be separated from composite signals using the selected target source impedance. Medical systems include a cardiac device having a housing that provides amplification circuitry configured to have a first amplifier input impedance and a second amplifier input impedance, such as using two separate circuits or switching between two input impedances. One or more electrode assemblies are coupled to the amplification circuitry. A signal processor is provided in the housing configured to separate a source signal using a first composite signal detected at the first input impedance and a second composite signal detected at the second input impedance. The phase response of the first input amplifier circuit is about equal to that of the second input amplifier circuit.

Abstract: A neural stimulator senses a reference signal indicative of cardiac cycles each including a predetermined type timing reference event using a sensor external to the heart and blood vessels. The delivery of the neural stimulation pulses are synchronized to that timing reference event. Examples of the timing reference event include a predetermined cardiac event such as a P-wave or an R-wave detected from a subcutaneous ECG signal, a predetermined type heart sound detected from an acoustic signal, and a peak detected from a hemodynamic signal related to blood flow or pressure.

Abstract: A method of determining a value for a respiration parameter in a test subject can include capturing—using a fully implanted system that includes a wireless transmitter and at least a first lead wire having a first electrode disposed thereon and a second lead wire having a second electrode disposed thereon—information indicative of an impedance measure between the first and second electrodes and across a thoracic region of the test subject; wirelessly transmitting, from the implanted system and to external equipment, the captured information; and determining a respiration parameter of the test subject based on the captured information.

Abstract: Implementing a subcutaneous medical electrode system involves positioning a number of electrode subsystems in relation to a heart so that noise cancellation provides an improved signal to noise ratio of the cardiac signal and/or to provide one electrode arrangement preferential for cardiac signals and another arrangement preferential for noise signals. One of the electrode subsystems so positioned may include one or more can electrodes located on a housing enclosing a medical device. The medical device may be configured to provide therapeutic, diagnostic, or monitoring functions, including, for example, cardiac arrhythmia therapy.

Abstract: A method embodiment comprises generating a neural stimulation signal for a neural stimulation therapy. The signal is generated during a duty cycle of a stimulation period to provide the neural stimulation therapy with an intensity at a therapy level for a portion of the duty cycle. In various embodiments, a ramp up protocol is implemented to begin the duty cycle, a ramp down protocol is implemented to end the duty cycle, or both the ramp up protocol and the ramp down protocol are implemented. The ramp up protocol includes ramping up the intensity from a non-zero first subthreshold level for the neural stimulation therapy at the beginning of the duty cycle to the therapy level. The ramp down protocol includes ramping down the intensity from the therapy intensity level to a non-zero second subthreshold level for the neural stimulation therapy at the end of the duty cycle.

Abstract: Methods and devices for classifying a cardiac response to pacing involve establishing a plurality of classification windows relative to and following a pacing pulse. One or more characteristics of a cardiac signal sensed following the pacing pulse are detected within one or more particular classification windows. The characteristics may be compared to one or more references. Classification of the cardiac response may be performed based on the comparison of the one or more characteristics to the one or more references and the particular classification windows in which the one or more characteristics are detected.

Abstract: Cardiac systems and methods using ECG and blood information for arrhythmia detection and discrimination. Detection circuitry is configured to produce an ECG. An implantable blood sensor configured to produce a blood sensor signal is coupled to a processor. The processor is coupled to the detection and energy delivery circuitry, and used to evaluate and treat cardiac rhythms using both the cardiac electrophysiologic and blood sensor signals. The blood sensor is configured for subcutaneous non-intrathoracic placement and provided in or on the housing, on a lead coupled to the housing, and/or separate to the housing and coupled to the processor via hardwire or wireless link. The blood sensor may be configured for optical sensing, using a blood oxygen saturation sensor or pulse oximeter. A cardiac rhythm may be evaluated using the electrocardiogram signal and the blood sensor signal, and tachyarrhythmias may be treated after confirmation using the blood sense signal.

Abstract: A neural stimulation system controls the delivery of neural stimulation using a respiratory signal as a therapy feedback input. The respiratory signal is used to increase the effectiveness of the neural stimulation, such as vagal nerve stimulation, while decreasing potentially adverse side effects in respiratory functions. In one embodiment, the neural stimulation system synchronizes the delivery of the neural stimulation pulses to the respiratory cycles using a respiratory fiducial point in the respiratory signal and a delay interval. In another embodiment, the neural stimulation system detects a respiratory disorder and, in response, adjusts the delivery of the neural stimulation pulses and/or delivers a respiratory therapy treating the detected respiratory disorder.

Abstract: A neural stimulation system controls the delivery of neural stimulation using a respiratory signal as a therapy feedback input. The respiratory signal is used to increase the effectiveness of the neural stimulation, such as vagal nerve stimulation, while decreasing potentially adverse side effects in respiratory functions. In one embodiment, the neural stimulation system detects apnea and, in response, adjusts the delivery of the neural stimulation pulses and/or delivers a respiratory therapy treating the detected apnea.

Abstract: An implantable medical device (IMD) comprising a controller adapted to execute instructions included in firmware, a programmable neural therapy source adapted to provide programmable electrical neural stimulation therapy to at least one neural stimulation electrode, and a state machine included in hardware circuitry coupled to the programmable neural therapy source. When neural therapy is initiated by a firmware instruction, the state machine is configured to automatically apply power to the neural therapy source when neural therapy is initiated by a firmware instruction and automatically remove power from the neural therapy source when neural therapy is terminated by a firmware instruction.

Abstract: Various aspects of the present subject matter relate to a method. According to various method embodiments, cardiac activity is detected, and neural stimulation is synchronized with a reference event in the detected cardiac activity. Neural stimulation is titrated based on a detected response to the neural stimulation. Other aspects and embodiments are provided herein.

Abstract: A system for providing stimulation current in implantable medical devices is provided. One aspect of this disclosure relates to an apparatus including a power supply terminal adapted to be connected to a power supply. The apparatus embodiment also includes circuitry connected to the power supply terminal and adapted to detect a parameter dependent on tissue/electrode impedance. The apparatus embodiment further includes a current output pulse generator adapted to deliver electrical therapy. The current generator includes an adjustable compliance voltage source connected to the power supply terminal. The compliance voltage source has a programmable amplitude and is adapted to provide different potentials for different tissue/electrode interface impedances. According to various embodiments, the apparatus embodiment also includes at least one stimulating electrode, and the current generator is adapted to deliver electrical therapy using the electrode. Other aspects and embodiments are provided herein.

Abstract: Methods and devices for classifying a cardiac response to pacing involve establishing a plurality of classification windows relative to and following a pacing pulse. One or more characteristics of a cardiac signal sensed following the pacing pulse are detected within one or more particular classification windows. The characteristics may be compared to one or more references. Classification of the cardiac response may be performed based on the comparison of the one or more characteristics to the one or more references and the particular classification windows in which the one or more characteristics are detected.

Abstract: An arrhythmia discrimination device and method involves receiving electrocardiogram signals and non-electrophysiologic signals at subcutaneous locations. Both the electrocardiogram signals and non-electrophysiologic signals are used to discriminate between normal sinus rhythm and an arrhythmia. An arrhythmia may be detected using electrocardiogram signals, and verified using the non-electrophysiologic signals. A detection window may be initiated in response to receiving the electrocardiogram signal, and used to determine whether the non-electrophysiologic signal is received at a time falling within the detection window. Heart rates may be computed based on both the electrocardiogram signals and non-electrophysiologic signals. The rates may be used to discriminate between normal sinus rhythm and an arrhythmia, and used to determine absence of an arrhythmia.

Abstract: Cardiac systems and methods using ECG and blood information for arrhythmia detection and discrimination. Detection circuitry is configured to produce an ECG. An implantable blood sensor configured to produce a blood sensor signal is coupled to a processor. The processor is coupled to the detection and energy delivery circuitry, and used to evaluate and treat cardiac rhythms using both the cardiac electrophysiologic and blood sensor signals. The blood sensor is configured for subcutaneous non-intrathoracic placement and provided in or on the housing, on a lead coupled to the housing, and/or separate to the housing and coupled to the processor via hardwire or wireless link. The blood sensor may be configured for optical sensing, using a blood oxygen saturation sensor or pulse oximeter. A cardiac rhythm may be evaluated using the electrocardiogram signal and the blood sensor signal, and tachyarrhythmias may be treated after confirmation using the blood sense signal.

Abstract: Various aspects relate to a device. Various device embodiments include at least a first and a second transducer, and a controller. The first transducer is adapted to be positioned to direct a first energy wave toward a neural target, and the second transducer is adapted to be positioned to direct a second energy wave toward the neural target. The controller is connected to the transducers to generate the first energy wave with a first predetermined phase and a first predetermined amplitude from the first transducer and to generate the second energy wave with a second predetermined phase and a second predetermined amplitude from the second transducer. The amplitudes are selected so that a neural stimulation threshold is reached only during constructive wave interference. The phases are selected so that the first and second energy waves constructively interfere at the neural target. Other aspects and embodiments are provided herein.

Abstract: Housings for implantable medical devices are configured so as to engage with surrounding tissues inside of a body and resist both rotation in place and movement through the body. Device housings include shapes, surface features, and/or standard surfaces and may include attached implements that engage the surrounding tissue. Shapes include elongated members, flared ends, and so forth. Surface features include pores, grooves, through-holes, and so forth. Attached implements include needles, barbs, tension springs, and so forth. Also provided are methods for engaging an implantable medical device with surrounding tissues.

Abstract: A method and device provide for determining capture in multiple chambers of a patient's heart using an electrode inserted into a coronary vein of the patient's heart. The coronary vein electrode is positioned adjacent to multiple heart chambers and is responsive to cardiac signals originating in the multiple chambers. The coronary vein electrode may be coupled to a single sense amplifier to detect the cardiac signals. Pace pulses may be applied to multiple heart chambers simultaneously or according to a phased timing sequence. Cardiac signals responsive to the pace pulses sensed using the coronary vein electrode may be used to verify capture in the multiple chambers of the heart.