Abstract: A system includes an implantable medical device configured to sense a sync signal and sense physiological parameters to obtain a physiological signal. In response to sensing the sync signal, the implantable medical device is configured to generate a sync-stamped physiological signal. In certain embodiments, a method includes receiving a first physiological signal coupled with a sync signal; receiving a second physiological signal coupled with the sync signal; and, using the sync signal, synchronizing in time the first and second physiological signals.

Abstract: Implantation of a cardiac stimulus system using the ITV. Superior, intercostal, and inferior access methods are discussed and disclosed. Superior access may be performed using the brachiocephalic vein to access the ITV, with access to the brachiocephalic vein achieved using subclavian vein, using standard visualization techniques. A positioning mechanism may be advanced to the ITV, a location of the positioning mechanism may then be obtained, and an external access may then be established. Inferior external access may be accomplished inferior to the lower rib margin via the superior epigastric or musculophrenic vein. Intercostal external access may be accomplished via an intercostal vein between two ribs. A lead may then be attached to the positioning mechanism and drawn into the ITV.

Abstract: Implantable leads of a cardiac stimulus system are disclosed, as well as methods for implanting leads of a cardiac stimulus system. The lead may be comprised of a proximal portion having a coupler for coupling to an implantable pulse generator, an intermediate portion comprising a plurality of electrodes disposed thereon, and a distal portion. The intermediate portion may have a first diameter and the distal portion may have a second diameter. The distal portion may also have an attachment feature for attaching to a lead pulling tool for delivery to an ITV and an intercostal vein. Methods may include pulling a lead from a first position to a second position within the vasculature, exiting the vasculature at the second location, and attaching a portion of the lead that exits the vasculature to an electrode or implantable device for use with the lead.

Abstract: A leadless pacing device may include a housing having a proximal end and a distal end, and a set of one or more electrodes supported by the housing. The housing may include a first portion and a second portion, with a guide wire port extending through the second portion. A guide wire lumen may extend through the second portion of the housing and the guide wire port may be located at a proximal end of the guide wire lumen. An exposed electrode may be located on a side of the housing that is opposite a side on which the guide wire port is located. The leadless pacing device may include a fixing member on the housing and extending radially from the housing. The leadless pacing device may further include a proximal member extending proximally from a proximal end of the housing. The proximal member may be elongated.

Abstract: A ventricularly implantable medical device that includes a sensing module that is configured to gather information during a cardiac cycle and to identify a cardiac interval based at least on part on the gathered information. Control circuitry in the implantable medical device is configured to deliver a ventricular pacing therapy to a patient's heart, wherein the ventricular pacing therapy is time dependent, at least in part, on the identified cardiac interval.

Abstract: Systems and methods for pacing cardiac conductive tissue are described. A medical system includes electrostimulation circuit that may generate His-bundle pacing (HBP) pulses for delivery at or near the His bundle. A capture verification circuit may detect, from a far-field signal representing ventricular response to the HBP pulses, a His-bundle response representative of excitation of the His bundle directly resulting from the HBP pulses, and a myocardial response representative of excitation of the myocardium directly resulting from the HBP pulses. A control circuit may adjust one or more stimulation parameters based on the His-bundle response and myocardial response. The electrostimulation circuit may generate and deliver the HBP pulses according to the adjusted stimulation parameters to excite the His bundle.

Abstract: An implantable medical device (IMD) is configured with a pressure sensor. The IMD includes a housing and a diaphragm that is exposed to the environment outside of the housing. The diaphragm is configured to transmit a pressure from the environment outside of the housing to a piezoelectric membrane. In response, the piezoelectric membrane generates a voltage and/or a current, which is representative of a pressure change applied to the housing diaphragm. In some cases, only changes in pressure over time are used, not absolute or gauge pressures.

Abstract: Systems and methods for pacing cardiac conductive tissue are described. A medical system includes an electrostimulation circuit to generate His-bundle pacing (HBP) pulses. A sensing circuit senses a physiologic signal, and detect a local His-bundle activation discrete from a pacing artifact of the HBP pulse. A control circuit verifies capture status in response to the HBP pulses. Based on the capture status, the control circuit determines one or more pacing thresholds including a selective HBP threshold representing a threshold strength to capture only the His bundle but not the local myocardium, and a non-selective HBP threshold representing a threshold strength to capture both the His bundle and the local myocardium. The electrostimulation circuit may deliver HBP pulses based on the selective and non-selective HBP thresholds.

Abstract: A ventricularly implantable medical device that includes a sensing module that is configured to identify a search window of time within a cardiac cycle to search for an atrial artifact. Control circuitry in the ventricular implantable medical device is configured to deliver a ventricular pacing therapy to a patient's heart, wherein the ventricular pacing therapy is time dependent, at least in part, on an atrial event identified in the search window of time.

Abstract: Systems and methods for monitoring and treating patients with heart failure are described. A signal receiver may receive a heart sound (HS) signal and an impedance signal sensed from the patient. A heart sound detector circuit may use at least the received impedance signal to determine a HS detection window, and detect a HS component indicative of cardiac diastolic function from the received HS signal within the HS detection window. The system may include a heart failure detector circuit that may generate a cardiac diastolic function indicator (DFI) using the detected HS component and, in certain examples, may detect worsening heart failure using the generated DFI. The system may include a therapy circuit to deliver or adjust an electrostimulation therapy based on DFI.

Abstract: An implantable medical device (IMD) includes a heterogeneous housing configured to receive and store one or more components of the IMD. The housing includes an intrinsically non-conductive and non-magnetic base material and at least one dopant with a property of at least one of electrical conductance and magnetic permeability. The base material and the dopant form a first region of the housing including a first skin depth and a second region of the housing including a second skin depth different than the first skin depth.

Abstract: Atrial fibrillation information can be determined from ventricular information or a ventricular location, such as using ventricular rate variability. An ambulatory medical device can receive indications of pairs of first and second ventricular rate changes of three temporally adjacent ventricular heart beats. A first count of instances of the pairs meeting a combined rate change magnitude characteristic and a second count of instances of the pairs in which both of the first and second ventricular rate changes are negative can be used to provide atrial fibrillation information.

Abstract: Systems and methods involve an intrathoracic cardiac stimulation device operable to provide autonomous cardiac sensing and energy delivery. The cardiac stimulation device includes a housing configured for intrathoracic placement relative to a patient's heart. A fixation arrangement of the housing is configured to affix the housing at an implant location within cardiac tissue or cardiac vasculature. An electrode arrangement supported by the housing is configured to sense cardiac activity and deliver stimulation energy to the cardiac tissue or cardiac vasculature. Energy delivery circuitry in the housing is coupled to the electrode arrangement. Detection circuitry is provided in the housing and coupled to the electrode arrangement. Communications circuitry may optionally be supported by the housing. A controller in the housing coordinates delivery of energy to the cardiac tissue or cardiac vasculature in accordance with an energy delivery protocol appropriate for the implant location.

Abstract: This document discusses, among other things, systems and methods to receive physiologic information of a patient, to receive pulse pressure information from the patient different than the received physiologic information, and to determine an indication of atrial fibrillation (AF) using the received physiologic information and the received pulse pressure information.

Abstract: Systems and methods for monitoring and treating patients with heart failure (HF) are discussed. The system may sense cardiac signals, and receives information about patient physiological or functional conditions. A stimulation parameter table that includes recommended values of atrioventricular delay (AVD) or other timing parameters maybe created at a multitude of patient physiological or functional conditions. The system may periodically reassess patient physiological or functional conditions. A therapy programmer circuit may dynamically switch between left ventricular-only pacing and biventricular pacing, or switch between single site pacing and multisite pacing based on the patient condition. The therapy programmer circuit may adjust AVD and other timing parameters using the cardiac signal input and the stored stimulation parameter table. A HF therapy may be delivered according to the determined stimulation site, stimulation mode, and the stimulation timing.

Abstract: An apparatus comprises an external device for communication with an implantable device. The external device includes a communication circuit configured to receive a communication signal from at least one other device different from the implantable device, a locating circuit configured to determine a location of the external device using the received communication signal, and a control circuit electrically coupled to the communication circuit and the locating circuit. The control circuit is configured to determine whether the determined location imposes a limit on functionality of an implantable device, and provide user access to an implantable device feature according to the determined location.

Abstract: A cardiac rhythm management system includes at least one sensing component configured to obtain a first physiological parameter signal, an indication of a cardiac response to a stimulation therapy, and temporal information corresponding to the first physiological parameter signal and the cardiac response; and at least one processor configured to: receive the first physiological parameter signal, the indication of the cardiac response, and the temporal information; and to classify the cardiac response into a first cardiac response class to generate a classified cardiac response. The at least one processor also is configured to determine a correlation, based on the temporal information, between the first physiological parameter signal and the classified cardiac response.

Abstract: Arterial diastolic pressure of a patient can be estimated using ventricular pressure information of a heart of the patient and heart sound information of the heart of the patient, such as a timing of at least one of a first heart sound (S1) or a second heat sound (S2), in certain examples, adjusted by a respective correction factor.

Abstract: Systems and methods for treating cardiac arrhythmias are disclosed. In one embodiment, an SICD comprises two or more electrodes, a charge storage device, and a controller operatively coupled to two or more of the electrodes and the charge storage device. In some embodiments, the controller is configured to monitor cardiac activity of the heart of the patient, detect an occurrence of a cardiac arrhythmia based on the cardiac activity, and determine a type of the detected cardiac arrhythmia from two or more types of cardiac arrhythmias. If the determined type of cardiac arrhythmia is one of a first set of cardiac arrhythmia types, the controller sends an instruction for reception by an LCP to initiate the application of ATP therapy by the LCP. If the determined type of cardiac arrhythmia is not one of the first set cardiac arrhythmia types, the controller does not send the instruction.

Abstract: An implantable medical device includes a housing. A first ID tag is secured relative to the housing at a first position and defines a first radiopaque manufacturer code section that visually identifies a manufacturer of the implantable medical device. A second ID tag is secured relative to the housing at a second position that is offset from the first position in at least one dimension. The second ID tag defines a second radiopaque manufacturer code section that also visually identifies the manufacturer of the implantable medical device.