Abstract: Techniques are provided for use by an implantable medical device or diagnostic sensor for detecting and discriminating euvolemia, hypervolemia and hypovolemia. In one example, the device detects a pressure signal within the patient representative of changes in cardiac pressure overall several cardiac cycles. The device generates separate time-domain and frequency-domain representations of the pressure signal and then discriminates among euvolemia, hypervolemia and hypovolemia within the patient based on an analysis of the time-domain and the frequency-domain representations of the signal. Depending upon the capabilities of the device, suitable warnings may be generated to alert the patient or caregiver. Diuretics or other medications can be titrated to address abnormal fluid conditions such as a fluid overload during hypervolemia. Techniques for detecting a pressure alternans pattern indicative of imminent decompensation are also described.

Abstract: Evaluation of an implanted electrical lead condition includes comparing electrogram template features with test electrogram features. The evaluating also includes determining the implanted electrical lead condition based solely on the electrogram comparison. The compared test electrogram features and template electrogram features may be atrial amplitudes and ventricular amplitudes. The sensing may be with a quad polar lead. The compared test electrogram features and electrogram template features may account for different patient postures and/or may account for respiration modulation.

Abstract: An apparatus and method for characterizing a region of interest (ROI) including measuring position and orientation data within the ROI; and generating a geometric data set to include one or more of: length, bifurcation location, angle and curvature characteristics of the ROI. Also, sequentially taking an image of a tool within the ROI; comparing tool dimensions with ROI dimensions; and estimating diameter, length, take-off angle, and/or tortuosity characteristics based on the comparisons.

Abstract: Pacing related timing is determined for an implantable medical device (IMD) by pacing at an RV pacing site, a first LV pacing site and a second LV pacing site in accordance with a first site, a second site and a third site pacing order, and further in accordance with a first inter-electrode pacing delay between pacing at the first site and pacing at the second site and a second inter-electrode pacing delay between pacing at the second site and pacing at the third site. At least one of a sensed event or a paced event is detected for at each of the second site and the third site. The first inter-electrode pacing delay and the second inter-electrode pacing delay are adjusted to avoid sensed events in favor of paced events at each of the second site and the third site. An atrio-ventricular delay may also be adjusted to avoid sensed events or lack of capture due to possible fusion at the first site, in favor of paced events at the first site.

Abstract: A renal denervation system includes a renal denervation catheter and a flow determining system. The renal denervation catheter includes a plurality of ablation members positioned at a distal end portion thereof. The renal denervation catheter is insertable into a renal artery. The flow determining system includes a processor and first and second flow determining members spaced apart on the renal denervation catheter. The processor is configured to determine a change in blood flow through the renal artery resulting from a renal denervation procedure using the renal denervation catheter in response to input from the first and second flow determining members.

Abstract: An ablation catheter includes an elongated body having a proximal end and a distal end. At least one ablation element is disposed on the body between the proximal end and the distal end and configured to ablate renal tissue to control hypertension. At least one localization sensor is disposed on the body and configured to interact with a magnetic field. The at least one localization sensor aids in determining an appropriate target tissue for ablation.

Abstract: An exemplary method includes positioning a lead in a patient where the lead has a longitudinal axis that extends from a proximal end to a distal end and where the lead includes an electrode with an electrical center offset from the longitudinal axis of the lead body; measuring electrical potential in a three-dimensional potential field using the electrode; and based on the measuring and the offset of the electrical center, determining lead roll about the longitudinal axis of the lead body where lead roll may be used for correction of field heterogeneity, placement or navigation of the lead or physiological monitoring (e.g., cardiac function, respiration, etc.). Various other methods, devices, systems, etc., are also disclosed.

Abstract: An exemplary method includes positioning a lead in a patient where the lead has a longitudinal axis that extends from a proximal end to a distal end and where the lead includes an electrode with an electrical center offset from the longitudinal axis of the lead body; measuring electrical potential in a three-dimensional potential field using the electrode; and based on the measuring and the offset of the electrical center, determining lead roll about the longitudinal axis of the lead body where lead roll may be used for correction of field heterogeneity, placement or navigation of the lead or physiological monitoring (e.g., cardiac function, respiration, etc.). Various other methods, devices, systems, etc., are also disclosed.

Abstract: Techniques are provided for controlling spinal cord stimulation (SCS) or other forms of neurostimulation. In one example, SCS treatment is delivered to a patient and nerve impulse firing signals are sensed along the spinal cord following the SCS treatment. The nerve impulse signals are analyzed to determine whether the signals are associated with effective SCS and then the delivery of additional SCS is controlled to improve SCS efficacy. For example, the nerve impulse signals can be analyzed to determine whether the signals are consistent with a positive patient mood associated with pain mitigation and, if not, SCS control parameters are adjusted to improve the efficacy of the SCS in reducing pain. In other examples, heart rate variability (HRV) is also used to control SCS. Still further, adjustments may be made to SCS control parameters to improve antiarrhythmic or sympatholytic effects associated with SCS. Techniques employing baseline/target calibration procedures are also described.

Abstract: Various embodiments of the present invention are directed to, or are for use with, an implantable system including a lead having multiple electrodes implantable in a patient's left ventricular (LV) chamber. In accordance with an embodiment, the patient's LV chamber is paced at first and second sites within the LV chamber using a programmed LV1-LV2 delay, wherein the LV1-LV2 delay is a programmed delay between when first and second pacing pulses are to be delivered respectively at the first and second sites within the LV chamber. Evoked responses to the first and second pacing pulses are monitored for, and one or more LV pacing parameter is/are adjusted and/or one or more backup pulse is/are delivered based on results of the monitoring.

Abstract: A nerve stimulation system includes a pulse generator and implantable lead. The pulse generator includes a sensing module and a pace circuit. The lead has an electrode array near the distal end and a connector at the proximal end for connection to the pulse generator. Conductors in the lead electrically connect the electrode array with the sensing module and pace circuit. The electrode array includes a first pair of small electrodes and a large electrode close to each other. The small electrodes and large electrode are physically separated from each other by insulative spaces extending generally transversely to a longitudinal axis of the lead. When the conductors are in electrical communication with the sensing module and pace circuit, the first pair of small electrodes are in electrical communication with both the sensing module and the pace circuit and the large electrode is in electrical communication with the pace circuit only.

Abstract: A wireless implantable system is provided that is externally powered and comprises of a closed-loop feedback for treating both patients with obstructive and central sleep apnea. A method is provided for treating sleep apnea using an implantable device. The method comprises sensing an inspiration (IN) signal representative of inspiration experienced by a patient from a respiratory surrogate signal and sensing a respiratory effort (RE) signal representative of an amount of effort exerted by the patient during respiration.

Abstract: The present disclosure provides systems and methods utilizing a closed-loop neurostimulation apparatus. The apparatus includes at least one sensing electrode that monitors neurological activity of a subject and at least one stimulating electrode that applies stimulation pulses to the subject. An internal pulse generator is coupled to the at least one sensing electrode and the at least one stimulating electrode. The internal pulse generator causes the at least one stimulating electrode to apply stimulating pulses based at least in part on the monitored neurological activity.

Abstract: The present disclosure provides systems and methods utilizing a noise stimulation apparatus. The apparatus includes at least one stimulating electrode and an implantable pulse generator coupled to the at least one stimulating electrode. The implantable pulse generator includes an accelerometer and a computing device coupled to the accelerometer. The computing device is configured to cause the implantable pulse generator to generate at least one stimulation pulse based on signals received from the accelerometer.

Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to perform arrhythmia discrimination based on activation times. A plurality of different sensing vectors are used to obtain a plurality of IEGMs that collectively enable electrical activations to be detected in the left atrial (LA) chamber, the right atrial (RA) chamber, and at least one ventricular chamber of a patient's heart. For each of a plurality of cardiac cycles, there is a determination, based on the plurality of obtained IEGMs, of an LA activation time, an RA activation time, and a ventricular activation time. Arrhythmia discrimination is then performed based on the determined activation times.

Abstract: Techniques are provided for controlling and delivering spinal cord stimulation (SCS) or other forms of neurostimulation. In one example, neurostimulation pulses are generated wherein successive pulses alternate in polarity so that a pair of electrodes alternate as cathodes. Each pulse has a cathodic amplitude sufficient to achieve cathodic capture of tissues adjacent the particular electrode used as the cathode for the pulse. The neurostimulation pulses are delivered to patient tissues using the electrodes to alternatingly capture tissues adjacent opposing electrodes via cathodic capture to achieve a distributed virtual stimulation cathode. Various pulse energy savings techniques are also set forth that exploit the distributed virtual stimulation cathode.

Abstract: A method for use with an implantable system including a lead having multiple electrodes implantable proximate to a patient's left ventricular (LV) chamber includes simultaneously delivering pacing pulses over corresponding pacing vectors defined by electrodes proximate to the LV chamber. The method includes recording evoked responses responsive to the pacing pulses that are measured over separate corresponding sensing channels. The method also includes comparing the evoked responses to a template that represents local capture of a local LV tissue region along one or more of the corresponding pacing vectors. The comparison is used to determine whether the pacing pulses achieved local capture along the corresponding pacing vectors. At least one of the pacing pulses or pacing vectors are updated based on the comparison of the evoked responses to the template in order to determine a local capture threshold for the corresponding pacing vectors.

Abstract: Methods and systems are provided to control a configuration of a neural stimulation (NS) system having an NS device coupled to an NS lead. The methods and systems change between configurations of the NS system and collect cardiac signals from a patient that are representative of cardiac rhythms experienced by the patient over a period of time and in connection with multiple NS configurations. The methods and systems derive, from the cardiac signals, characteristic values for at least one physiologic characteristic indicative of at least one of normal and abnormal cardiac rhythms in connection with the multiple NS configurations; and select, from the multiple NS configurations, an NS operating configuration to be used by the NS system based on the characteristic values.

Abstract: Techniques are provided for use with an implantable medical device for assessing left ventricular (LV) sphericity and atrial dimensional extent based on impedance measurements for the purposes of detecting and tracking heart failure and related conditions such as volume overload or mitral regurgitation. In some examples described herein, various short-axis and long-axis impedance vectors are exploited that pass through portions of the LV for the purposes of assessing LV sphericity. In other examples, impedance measurements taken along a vector between a right atrial (RA) ring electrode and an LV electrode implanted near the atrioventricular (AV) groove are exploited to assess LA extent, biatrial extent or mitral annular diameter. The assessment techniques can be employed alone or in conjunction with other heart failure detection techniques, such as those based on left atrial pressure (LAP.

Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to perform arrhythmia discrimination. A plurality of different sensing vectors are used to obtain a plurality of different IEGMs, each of which is indicative of cardiac electrical activity at a different ventricular region. The plurality of different IEGMs can include, e.g., an IEGM indicative of cardiac electrical activity at a first region of the patient's left ventricular (LV) chamber and an IEGM indicative of cardiac electrical activity at a second region of the patient's LV chamber. Additionally, the plurality of different IEGMs can further include an IEGM indicative of cardiac electrical activity at a region of a patient's right ventricular (RV) chamber. For each of the IEGMs, there is a determination of a corresponding localized R-R interval stability metric indicative of the R-R interval stability at the corresponding ventricular region. This can include, e.g.