Abstract: A system for automatically evaluating the sensing and detection of physiological processes by an implantable medical device, such as an implantable cardiac stimulation device. The system includes an automatic testing algorithm which iteratively adjusts at least one of the threshold and gain settings of the device and evaluates the accuracy of the detection for refining the programming of the device. The algorithm can include sampling the physiological process beginning at a relatively low rate to avoid excessive burden on the processing and battery capacity available and progressively increasing the rate to obtain higher resolution data. The algorithm can also evaluate the observed physiological process for periodicity and can determine repetition of an irregular pattern, such as bigeminy, and use the determined pattern for predictive purposes to refine the programming of the device. The algorithm employs observation of a change in observed pattern as indicia for loss of proper detection.
Abstract: A first lead provides therapeutic stimulation to the heart and includes a first mechanical sensor that measures physical contraction and relaxation of the heart. A controller induces delivery of therapeutic stimulation via the first lead. The controller receives signals from the first mechanical sensor indicative of the contraction and relaxation; develops a template signal that corresponds to the contraction and relaxation; and uses the template signal to modify the delivery of therapeutic stimulations. In another arrangement, a second lead, with a second mechanical sensor also provides signals to the controller indicative of contraction and relaxation. The first mechanical sensor is adapted to be positioned at the interventricular septal region of the heart, and the second mechanical sensor is adapted to be positioned in the lateral region of the left ventricle. The controller processes the signals from the first mechanical sensor and the second mechanical sensor to develop a dysynchrony index.
Abstract: Techniques are described for detecting and distinguishing among ischemia, hypoglycemia or hyperglycemia based on intracardiac electrogram (IEGM) signals. In one technique, these conditions are detected and distinguished based on an analysis of: the interval between the QRS complex and the peak of a T-wave (QTmax), the interval between the QRS complex and the end of a T-wave (QTend), alone or in combination with a change in ST segment elevation. By exploiting QTmax and QTend in combination with ST segment elevation, changes in ST segment elevation caused by hypo/hyperglycemia can be properly distinguished from changes caused by cardiac ischemia. In another technique, hyperglycemia and hypoglycemia are predicted, detected and/or distinguished from one another based on an analysis of the amplitudes of P-waves, QRS-complexes and T-waves within the IEGM. Appropriate warning signals are delivered and therapy is automatically adjusted.
Abstract: A method of providing cardiac stimulation therapy and a device for providing the therapy. A patient's cardiac activity as well as cyclical respiration is monitored. Cardiac stimulation is provided as indicated as therapeutic intervention for a variety of cardiac arrhythmias according to variable timing parameters. One or more of the timing parameters under which cardiac pacing stimulations are provided is varied or modulated with the cyclical variations in respiration. The one or more timing parameters are generally shortened or elongated in concert with the alternating inspiration/exhalation phases of respiration. In certain implementations, the patient's respiration is inferred from cardiac based physiologic signals. The methods and devices for providing cardiac stimulation therapy more accurately emulate natural healthy physiologic activity.
Abstract: An implantable medical lead configured to reduce resonant currents in a resonating circuit during MRI scans and a method of manufacturing the same are disclosed herein. The method of manufacturing includes providing a medical lead comprising an electrical pathway from a tip electrode located at a distal end of the lead to a lead connector located at a proximal end and coupling a resonating circuit to the tip electrode such that the resonating circuit is in the electrical pathway for the tip electrode. Further, the method includes coupling a capacitive element to a proximal end of the resonating circuit. The capacitive element is configured to shunt at least part of an RF current induced on the electrical pathway into surrounding tissue or fluid and also works as a heat sink to spread the heat from the internal LC resonant circuit.
Type:
Application
Filed:
June 2, 2010
Publication date:
December 8, 2011
Applicant:
PACESETTER, INC.
Inventors:
Jin Zhang, Xiaoyi Min, Ingmar Viohl, Gabriel A. Mouchawar, Xiangqun Chen
Abstract: An exemplary method includes providing a mechanical activation time (MA time) for a myocardial location, the location defined at least in part by an electrode and the mechanical activation time determined at least in part by movement of the electrode; providing an electrical activation time (EA time) for the myocardial location; and determining an electromechanical delay (EMD) for the myocardial location based on the difference between the mechanical activation time (MA time) and the electrical activation time (EA time).
Type:
Application
Filed:
August 9, 2011
Publication date:
December 1, 2011
Applicant:
PACESETTER, INC.
Inventors:
Stuart Rosenberg, Allen Keel, Kyungmoo Ryu, Wenbo Hou, Kjell Norén, Thao Thu Nguyen, Michael Yang
Abstract: An implantable medical device includes a lead, a pulse generator, a cardiac signal module, a fusion detection module and a rate modification module. The lead includes electrodes that are configured to be positioned within a heart to sense cardiac signals of the heart. The pulse generator delivers stimulus pulses to the heart through at least one of the electrodes. The cardiac signal module monitors the cardiac signals and directs the pulse generator to deliver one or more of the stimulus pulses to the heart at a stimulation rate based on the cardiac signals. The fusion detection module identifies a presence of fusion-based behavior of the heart that is associated with delivery of the one or more of the stimulus pulses. The rate modification module then adjusts the stimulation rate based on the presence of the fusion-based behavior.
Abstract: An exemplary method includes emitting radiation subcutaneously; sensing at least some of the emitted radiation as reflected cutaneously; detecting an abnormal physiologic condition; and, based at least in part on the sensing, adjusting a stimulation therapy to treat the detected abnormal condition. In such a method, the abnormal condition may be an abnormal cardiac condition, an abnormal neural condition or other condition. Various other methods, devices, systems, etc., are also disclosed.
Abstract: An implantable system acquires intracardiac impedance with an implantable lead system. In one implementation, the system generates frequency-rich, low energy, multi-phasic waveforms that provide a net-zero charge and a net-zero voltage. When applied to bodily tissues, current pulses or voltage pulses having the multi-phasic waveform provide increased specificity and sensitivity in probing tissue. The effects of the applied pulses are sensed as a corresponding waveform. The waveforms of the applied and sensed pulses can be integrated to obtain corresponding area values that represent the current and voltage across a spectrum of frequencies. These areas can be compared to obtain a reliable impedance value for the tissue. Frequency response, phase delay, and response to modulated pulse width can also be measured to determine a relative capacitance of the tissue, indicative of infarcted tissue, blood to tissue ratio, degree of edema, and other physiological parameters.
Type:
Grant
Filed:
March 12, 2007
Date of Patent:
November 22, 2011
Assignee:
Pacesetter, Inc.
Inventors:
Louis Wong, Cem Shaquer, Gene A. Bornzin, Euljoon Park, Andre Walker, Dorin Panescu, Jiong Xia, Shahrooz Shahparnia
Abstract: Implantable systems, and methods for use therewith, are provided for using an implantable sensor for detecting body position and/or body movement, and using what is learned therefrom to improve accuracy of an implantable sensor that is sensitive to at least one of body position and/or body movement. Also provided are implantable systems, and methods for use therewith, that detect body position and/or body movement in order to monitor a condition and/or detect specific episodes. Other embodiments are also provided.
Abstract: A septum for use in an implantable pulse generator. The septum includes a soft sealing material and a hard inner portion or core having a set of lips. The lips are exposed outside the soft sealing material and act to displace the sealing material when a force is applied, for example from a tool used to tighten or loosen a set screw, enlarging a slit, seam or slot into a passageway through the septum.
Abstract: A cardiac analysis system is provided that includes an implantable medical device (IMD), at least one sensor, and an external device. The IMD has electrodes positioned proximate to a heart that sense first cardiac signals of the heart and associated with a clinical ventricular tachycardia (VT) event and second cardiac signals associated with an induced VT event. The sensor measures first and second cardiac parameters of the heart associated with the clinical and induced VT events, respectively. The external device is configured to receive the first and second cardiac signals associated with the clinical and the induced VT events and the first and second cardiac parameters associated with the clinical and the induced VT events. The external device compares the first and second cardiac signals and compares the first and second cardiac parameters to determine if the clinical and induced VT events are a common type of VT event.
Type:
Application
Filed:
June 22, 2010
Publication date:
November 17, 2011
Applicant:
PACESETTER, INC.
Inventors:
Michael E. Benser, Gene A. Bornzin, Euljoon Park, Kyungmoo Ryu, Michael Hardage
Abstract: Techniques are described for discriminating ventricular tachycardia (VT) from supraventricular tachycardia (SVT) in circumstances when the ventricular rate exceeds the atrial rate (i.e. V>A). In one example, an initial atrial rate is detected while employing adjustable atrial channel detection parameters that can affect the detection of the true atrial rate—such as a post-ventricular atrial blanking (PVAB) interval or an atrial channel sensitivity level. If the ventricular rate exceeds a VT rate zone threshold with V>A, the device does not immediately deliver high voltage shock therapy as done in other devices. Rather, the device instead selectively adjusts the atrial channel detection parameter(s) to determine if the true atrial rate is equal to the ventricular rate. If so, then such is an indication that the arrhythmia might be SVT rather than VT and various discrimination procedures are employed to distinguish SVT from VT before therapy is delivered.
Abstract: An implantable medical lead comprising a conductor extending along the lead and a crimp connector secured to the conductor comprising a body with an outer surface, an inner surface, proximal and distal ends, and first and second lateral edges, the lateral edges having edge features extending there from, the edge features adapted to opposingly interleave with one another. Methods of assembling a crimp connector with a cable conductor including parallel and cross-wise assembly are also encompassed.
Abstract: An exemplary method includes detecting fibrillation, measuring impedance of a defibrillation circuit that includes myocardial tissue, determining one or more defibrillation shock parameters based at least in part on the impedance, delivering a defibrillation shock using the one or more defibrillation shock parameters and, if the shock was unsuccessful, adjusting a membrane time constant and determining one or more new defibrillation shock parameters based at least in part on the adjusted membrane time constant. Various other exemplary methods are disclosed as well as various exemplary devices, systems, etc.
Abstract: Exemplary external medical devices are configurable to communicate with an implantable medical device (IMD). One medical device includes multiple IMD telemetry ports operable to connect IMD telemetry mechanisms to the medical device. The medical device also includes a control unit configured to control the IMD telemetry mechanisms.
Type:
Grant
Filed:
April 17, 2007
Date of Patent:
November 15, 2011
Assignee:
Pacesetter, Inc.
Inventors:
Ronald R. Rios, Gregory C. Bevan, Eliot L. Ostrow, Armando M. Cappa, Allan R. Schwartz, George L. Walls
Abstract: Techniques are provided for evaluating mechanical dyssynchrony within the heart of patient in which a pacemaker, implantable cardioverter-defibrillator (ICD) or other medical device is implanted. In one example, a set of cardiogenic impedance signals are detected along different sensing vectors passing through the heart of the patient, particularly vectors passing through the ventricular myocardium. A measure of mechanical dyssynchrony is detected based on differences, if any, among the cardiogenic impedance signals detected along the different vectors. In particular, differences in peak magnitude delay times, peak velocity delay times, peak magnitudes, and waveform integrals of the cardiogenic impedance signals are quantified and compared to detect abnormally contracting segments, if any, within the heart of the patient. Warnings are generated upon detection of any significant increase in mechanical dyssynchrony. Diagnostic information is recorded for clinical review.
Abstract: An assembly for the delivery of a cardiac surgical device is disclosed herein. In one embodiment, the assembly includes a slittable delivery device and a bypass assembly. The slittable delivery device may include a hub, a shaft integrated into the hub and forming at least a segment of the circumferential surface of the hub, and a hemostasis valve contained substantially within the hub. The bypass assembly may include a cap and a valve bypass tool. The cap may be on a proximal end of the hub and may include an opening in the cap extending radially outward from a point near a radial center of the cap through a circumferential edge of the cap. The valve bypass tool may be operably coupled to the cap and may include a longitudinally extending open channel.
Type:
Grant
Filed:
March 25, 2009
Date of Patent:
October 25, 2011
Assignee:
Pacesetter, Inc.
Inventors:
Heather Helgeson, Dale Price, John Hastings, Brian Swanson, Ross Marks
Abstract: An implanted device is equipped with a flag that indicates to a remote monitoring unit that an event such as a patient medical emergency or device failure has occurred. The remote monitoring unit is configured in some embodiments to maintain a low power communication link with the implanted device when they are within range. When the flag indicates an event has occurred, the remote monitoring unit quickly downloads sensed data collected by the implanted device and transfers it over a network so that it can be utilized by a medical practitioner. The remote monitoring unit is further configured in some embodiments to query the implanted device at regular intervals. The remote monitoring unit may read a subset of the data stored by the implanted device and, based on that data, determine whether to complete a full or partial download.
Abstract: Anode foil, preferably aluminum anode foil, is etched using a process of treating the foil in an electrolyte bath composition comprising a sulfate and a halide, such as sodium chloride. The anode foil is etched in the electrolyte bath composition by passing a charge through the bath. The etched anode foil is suitable for use in an electrolytic capacitor.
Type:
Grant
Filed:
July 16, 2009
Date of Patent:
October 18, 2011
Assignee:
Pacesetter, Inc.
Inventors:
Xiaofei Jiang, Tearl Stocker, R. Jason Hemphill, Thomas F. Strange