Abstract: An implantable medical lead for coupling to an implantable pulse generator may be configured for improved MRI safety. The lead may include: a tubular body including a proximal end and a distal end; a first electrode operably coupled to the tubular body near the distal end; and a first electrical coil conductor extending distally through the body from the proximal end and electrically connected to the first electrode. The coil conductor may include at least one transition in which the coil conductor changes from being helically coiled in a first direction to being helically coiled in a second opposite direction. A method of forming such a lead may include: helically coiling at least a portion of a first electrical coil conductor by winding the coil conductor in a first direction, and winding the coil conductor in a second direction opposite the first direction so as to form a transition.

Abstract: An implantable medical device includes leads, a segment monitoring module, an impedance detection module and an ischemia module. The leads include electrodes that are configured to be positioned within a heart and that are capable of sensing cardiac signals having a segment of interest. The segment monitoring module determines segment variations of the segment of interest in the cardiac signals. The impedance detection module measures impedance vectors between predetermined combinations of the electrodes. The ischemia detection module monitors ischemia based on changes in the segment variations of the segment of interest and based on changes in the impedance vectors.

Abstract: A system and method for powering an implantable cardiac therapy device (ICTD) via a hybrid battery system. The hybrid battery is comprised of a low voltage and low current bioelectric cell, a high voltage and high current rechargeable cell, and a charging means. Via the charging means, the bioelectric cell maintains the rechargeable cell at or near full power. The rechargeable cell is configured to power some or all operations of the ICTD. Some ICTD operations may be powered directly by the bioelectric cell. The rechargeable cell is further configured to be charged via a continuous charging process, reducing the complexity of the charging circuitry. In an embodiment, at least the bioelectric cell is external to the ICTD, enabling easy replacement of this power source. In an embodiment, a consumable anode of the bioelectric cell is external to the ICTD, enabling replacement of the power source by replacing only the anode.

Abstract: An implantable medical lead is disclosed herein. In one embodiment, the lead includes a body and an electrical pathway. The body may include a distal portion with an electrode and a proximal portion with a lead connector end. The electrical pathway may extend between the electrode and lead connector end and include a coiled inductor including a first portion and a second portion at least partially magnetically decoupled from the first portion. The first portion may include a first configuration having a first SRF. The second portion may include a second configuration different from the first configuration. The second configuration may have a second SRF different from the first SRF. For example, the first SRF may be near 64 MHz and the second SRF may be near 128 MHz.

Abstract: An exemplary system includes a programmer configured to instruct an implantable device and a qualification module with instructions to call for tests performed by an implantable device configured for delivery of CRT, to receive results from the tests, to analyze the results and to decide, based on the analysis, if the patient qualifies for automatic, implantable device-based optimization of one or more CRT parameters and, only if the patient qualifies for automatic, implantable device-based optimization of one or more CRT parameters, presenting a graphical user interface that comprises a selectable control to enable an algorithm of an implantable device to automatically optimize at least one of the one or more cardiac resynchronization therapy parameters. Other exemplary methods, devices, systems, etc., are also disclosed.

Abstract: A system and method provide precise detection of the time of occurrence of a cardiac event of a heart. The method comprises the steps of sensing electrical activity of the heart to generate an electrogram of the heart and applying the electrogram to an event detector having a plurality of spaced apart thresholds. The thresholds are selected such that the electrogram has an amplitude for crossing at least one of the thresholds. The method further comprises determining a characteristic identifying feature of the electrogram at each threshold crossing of the electrogram, comparing the determined characteristic identifying features to an electrogram template, and identifying the time of occurrence of the cardiac event based upon the comparison.

Abstract: Exemplary systems, devices, and methods pertaining to cardiac related therapy and particularly to interferential cardiac preconditioning and depolarization are described. A cardiac arrhythmia is detected from electrogram data sensed from a patient's heart and a region of the heart affected by the cardiac arrhythmia is determined. The affected region is the interferentially energized by multiple cycles of two concurrently delivered alternating currents which are offset in frequency.

Abstract: Systems and techniques are provided for controlling vagus nerve stimulation (VNS) delivered by an implantable medical device for mitigating heart failure in a patient. In one mode, VNS therapy is set to levels just below a heart rate reduction threshold so as to deliver VNS near the highest stimulation levels that can be achieved without reducing patient heart rate. In this manner, a maximum level of heart failure mitigation can be achieved via VNS therapy without incurring the potentially adverse consequences of inducing bradycardia within the patient. In another mode, VNS therapy is instead controlled to deliver VNS above the threshold so as to mitigate heart failure while also selectively reducing heart rate, as may be appropriate in patients susceptible to cardiac ischemia. A controlled heart rate reduction curve may additionally or alternatively be determined for use in achieving target amounts of heart rate reduction.

Abstract: Exemplary techniques and systems for interpolating left ventricular pressures are described. One technique interpolates pressures within the left ventricle from blood pressures gathered without directly sensing blood pressure in the left ventricle.

Abstract: Provided herein are implantable devices, and methods for use therewith, that independently monitor levels of parasympathetic and sympathetic tone of a patient. In accordance with an embodiment, a cardiac electrogram (EGM) signal is sensed using implanted electrodes, cardiac intervals are measured within a portion of the sensed EGM signal, and levels of parasympathetic tone and sympathetic tone are independently assessed based on the measured cardiac intervals. This abstract is not intended to describe all of the various embodiments of the present invention.

Abstract: Methods, lead retention assemblies and systems may provide a secure connection of electrical leads to an implantable medical device, such as a pacemaker or a defibrillator. The method may include: providing a lead retention assembly including a support member, a first side clamp and a second side clamp, a first port and a second port each defining a respective receptacle in conjunction with the support, and a fastener configured to urge both the first and second side clamps toward the support upon actuation of the fastener; providing at least two electrical lead bodies each including a respective proximal end portion; inserting the respective proximal end portions into the respective receptacles to be in electrical communication with a respective electrical contact in the respective receptacles; and actuating the fastener to thereby clamp the proximal end portions of the respective electrical lead bodies within the first and second ports.

Abstract: An implantable medical device includes a device body at least partially formed of a polymeric material including a base polymer and a block copolymer. The block copolymer includes at least one polyethylene oxide (PEO) block and at least one silicone (SI) block, wherein the weight average molecular weight of the block copolymer is in the range of about 400 to about 50,000.

Abstract: A lead fixation device that includes a helix having a surface, and a layer of electrically insulating material that covers one or more selected regions of the surface leaving one or more additional regions of the surface exposed. The insulating material defines one of a plurality of individual exposed portions along the length of the helix having a plurality of different configurations, e.g. shapes and sizes, or an insulating strip that wraps around the helix while advancing along the length of the helix.

Abstract: Systems and methods are provided for reducing heating within pacing/sensing leads of a pacemaker or implantable cardioverter-defibrillator that occurs due to induced loop currents during a magnetic resonance imaging (MRI) procedure, or in the presence of other sources of strong radio frequency (RF) fields. For example, bipolar coaxial leads are described herein wherein the ring conductor of the lead is disconnected from the ring electrode in response to detection of MRI fields so as to convert the ring conductor into an RF shield for shielding the inner tip conductor of the lead so as to reduce the strength of loop currents induced therein and hence reduce tip heating. Techniques are also described herein for selectively disconnecting the tip electrode of the lead during an MRI procedure, except during actual delivery of pacing pulses, so as to permit delivery of individual pacing pulses to pacemaker dependent patients during the MRI.

Abstract: Systems and methods are provided for reducing heating within pacing/sensing leads of a pacemaker or implantable cardioverter-defibrillator that occurs due to induced radio frequency (RF) currents during a magnetic resonance imaging (MRI) procedure, or in the presence of other sources of strong RF fields. For example, bipolar coaxial leads are described wherein the ring conductor of the lead is disconnected from the ring electrode via a switch in response to detection of MRI fields to convert the ring conductor into an RF shield for shielding the inner tip conductor of the lead so as to reduce the strength of RF currents induced therein and hence reduce tip heating. Other exemplary leads are described wherein a band stop filter is instead used to block RF signals to likewise convert the ring conductor into an RF shield. The switches and band stop filters also help to prevent MRI-induced stimulation.

Abstract: Systems and methods for determining whether there is a correlation between arrhythmias and myocardial ischemic episodes are provided. An implantable system (e.g., a monitor, pacemaker or ICD) is used to monitor for arrhythmias and to monitor for myocardial ischemic episodes. When such events are detected by the implantable system, the implantable system stores (e.g., in its memory) data indicative of the detected arrhythmias and data indicative of the detected myocardial ischemic episodes. Then, for each detected arrhythmia, a determination is made based on the data, whether there was a myocardial ischemic episode detected within a specified temporal proximity of (e.g., within a specified amount of time of) the arrhythmia. Where a myocardial ischemic episode occurred within the specified temporal proximity of an arrhythmia, data for the two events can be linked.

Abstract: Techniques are provided for improving cardiac output and also suppressing certain forms of apnea/hypopnea within a patient using an implantable medical device, such as a pacemaker or ICD. In one example, a selected pacing parameter—usually the pacing rate—is temporarily altered by an amount sufficient to elevate cardiac output, the elevation in cardiac output being eventually reduced by intrinsic compensatory mechanisms within the patient. The pacing parameter is then temporarily reset for a duration sufficient to allow the compensatory mechanisms to return toward a previous state so as to permit a subsequent alteration in the pacing parameter to again elevate cardiac output. The pacing parameter is repeatedly altered and reset so as to achieve an overall increase in cardiac output despite the intrinsic compensatory mechanisms. The increase in cardiac output is often sufficient to suppress certain forms of apnea/hypopnea, particularly apnea/hypopnea arising from Cheyne-Stokes Respiration (CSR).

Abstract: Cardiac pacing may be controlled through retrospective detection of events that are sensed during a given period of time. In some embodiments a detection decision is made substantially prior to the end of an escape interval. In some embodiments the mode of detection may be changed near the end of the period of time. In some embodiments the period of time is extended when an event is detected near the end of the period of time.

Abstract: Techniques for communicating with implantable medical devices (IMDs) in a manner that promotes efficient data retrieval are described. The techniques involve ways to streamline retrieval of data stored on a patient's IMD. In one exemplary technique, first and second data ranges are determined for retrieval from an IMD. The technique evaluates whether the first data range overlaps or is separated by less than a predefined amount from the second data range. In an event where the first and second data ranges overlap or are separated by less than the predefined amount, the technique requests a third data range from the IMD which encompasses the first and second data ranges.

Abstract: The invention relates to an apparatus and method to assess the fluid level in lungs. An implantable medical device or external monitor is used to sense or monitor the patient's respiratory patterns to identify the presence of periodic breathing or Cheyne-Stokes Respiration (CSR) which is common in patients with congestive heart failure. A fluid index is used to assess the severity of congestive heart failure in a patient. A ratio of ? blood gas/?total lung volume can be used to determine the lung fluid index.