Patents by Inventor Todd Sheldon

Todd Sheldon has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9254392
    Abstract: Systems and methods are described herein for determining whether anodal capture of the right ventricle is occurring when delivering left ventricular pacing with a cross-chamber pacing vector. The systems and methods may be measure cross-chamber sense times from left ventricular pacing and right ventricular pacing and compare the cross-chamber sense times to determine whether anodal capture of the right ventricle is occurring.
    Type: Grant
    Filed: December 31, 2013
    Date of Patent: February 9, 2016
    Assignee: Medtronic, Inc.
    Inventors: Subham Ghosh, Todd Sheldon
  • Publication number: 20150182751
    Abstract: Systems and methods are described herein for determining whether anodal capture of the right ventricle is occurring when delivering left ventricular pacing with a cross-chamber pacing vector. The systems and methods may be measure cross-chamber sense times from left ventricular pacing and right ventricular pacing and compare the cross-chamber sense times to determine whether anodal capture of the right ventricle is occurring.
    Type: Application
    Filed: December 31, 2013
    Publication date: July 2, 2015
    Inventors: Subham Ghosh, Todd Sheldon
  • Publication number: 20100198295
    Abstract: Techniques are described for performing an extended capture detection test after detecting inadequate capture during a first capture detection test. An example system includes an implantable medical device that delivers pacing pulses to a patient, that periodically performs a first capture detection test to detect capture or loss of capture of the pacing pulses, and that detects inadequate capture during the first capture detection test, wherein in response to detecting the inadequate capture, the implantable medical device performs a second capture detection test that is longer than the first test. The system also includes a programmer device that programs the implantable medical device and that retrieves data from the implantable medical device corresponding to the second capture detection test. The example system may conserve battery power and prevent loss of current by performing the extended capture detection test only after detection of inadequate capture during the first test.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 5, 2010
    Applicant: Medtronic, Inc.
    Inventors: Todd Sheldon, Lynn A. Davenport
  • Publication number: 20070250127
    Abstract: An implantable medical device (IMD) performs periodic testing of a patient to determine ischemia threshold information. At selected times while the patient is at rest, the IMD increases the pacing rate over time until it receives feedback either from the patient or from an ischemia sensor. The IMD determines the threshold based upon the pacing rate at the time when the feedback was received. The threshold information can be used to adjust the upper pacing rate that can be used during rate adaptive pacing, to determine the effects of drug therapy, and to provide a general indication of the state of coronary artery disease in the patient. The periodic increase of pacing rate to the ischemic zone also provides a preconditioning of the myocardium to allow the patient greater exercise benefit without angina.
    Type: Application
    Filed: April 19, 2006
    Publication date: October 25, 2007
    Inventors: Lee Stylos, Todd Sheldon, Steven Lu, William Combs, Robert Nehls
  • Publication number: 20070213777
    Abstract: Pacing parameters are provided to address cross talk and intrinsic ventricular events occurring within a predefined blanking period following an atrial event. The parameters are used in conjunction with protocol for minimizing or reducing ventricular pacing, wherein ignoring intrinsic ventricular events during the blanking period might otherwise affect the performance of the protocol.
    Type: Application
    Filed: May 15, 2007
    Publication date: September 13, 2007
    Inventors: Robert Betzold, David Casavant, Paul Belk, Thomas Mullen, John Stroebel, Steven Hornberger, Todd Sheldon, Douglas Peterson
  • Publication number: 20070203524
    Abstract: An implantable medical device system and method in which the implantable device is adapted to operate in a minimum ventricular pacing mode. The device delivers cardiac pacing pulses in a first pacing mode during a normal mode of operation and upon detecting myocardial ischemia alters the first pacing mode in response to the myocardial ischemia detection.
    Type: Application
    Filed: February 28, 2006
    Publication date: August 30, 2007
    Inventors: Todd Sheldon, William Combs, Lee Stylos, Steven Lu, Robert Nehls
  • Publication number: 20070167843
    Abstract: A system and method for monitoring respiration including sensing a signal that varies with respiration, deriving a respiration parameter, applying criteria for detecting a respiration disturbance and determining one or more respiratory disturbance metrics. The system preferably includes an implantable sensor with an associated implantable medical device such that chronic respiration monitoring is possible. The implantable medical device may execute methods for detecting and measuring respiratory disturbances or may store data to be transferred to an external device for detecting and measuring respiratory disturbances. Respiratory disturbance detection may trigger a responsive action such as physiological data storage, a change in therapy delivery, or a clinician warning. Assessment of cardiac function may be made based on metrics of respiratory disturbances or a measure of circulatory delay time following detection of a respiratory disturbance.
    Type: Application
    Filed: November 30, 2006
    Publication date: July 19, 2007
    Inventors: Yong Cho, Steven Lu, Luc Mongeon, Scott Davie, Todd Sheldon, Mark Erickson, H. Markowitz
  • Publication number: 20060247705
    Abstract: Embodiments of the invention provide systems and methods for an implantable medical device comprising means for selecting between an atrial chamber reset (ACR) test and an atrioventricular conduction (AVC) test to provide atrial capture management and means for switching between an atrial-based pacing mode and a dual chamber pacing mode based on detecting relatively reliable atrioventricular conduction.
    Type: Application
    Filed: April 27, 2005
    Publication date: November 2, 2006
    Inventors: John Rueter, Todd Sheldon
  • Publication number: 20060241701
    Abstract: Subcutaneous Implantable cardioverter-defibrillators (SubQ ICDS) are disclosed that are entirely implantable subcutaneously with minimal surgical intrusion into the body of the patient and provide distributed cardioversion-defibrillation sense and stimulation electrodes for delivery of cardioversion-defibrillation shock and pacing therapies across the heart when necessary. The SubQ ICD is implemented with other implantable and external medical devices and communicates to provide drugs and therapy in a coordinated and synergistic manner.
    Type: Application
    Filed: April 26, 2005
    Publication date: October 26, 2006
    Inventors: H. Markowitz, Douglas Hettrick, William Combs, Todd Sheldon
  • Publication number: 20060161207
    Abstract: In bi-ventricular pacing devices (including CRT devices) analysis of myocardial electrogram signals in one ventricle (e.g., a left ventricle, or “LV”) can be used to infer capture or loss-of-capture (LOC) of an earlier stimulus pulse in the same ventricle, on a continuous (every pacing cycle), triggered, aperiodic and/or periodic basis. Rather than using an evoked-response principle as has been the basis of capture detection in prior art and other systems, a principle employed via the present invention uses evidence of inter-ventricular conduction (i.e., from the opposite chamber) and/or atrio-ventricular conduction as evidence of LOC, since a non-capturing pacing stimulus provided to a first chamber will allow the myocardial tissue of the first chamber to remain non-refractory and thus inter-ventricular and atrio-ventricular wavefront propagation and conduction can commence and be detected thereby revealing whether LOC has occurred.
    Type: Application
    Filed: December 20, 2005
    Publication date: July 20, 2006
    Inventors: James Busacker, Todd Sheldon
  • Publication number: 20060149328
    Abstract: The invention provides methods and apparatus for determining in a non-tracking pacing mode (e.g., DDI/R, VVI/R) whether a ventricular pacing stimulus is capturing a paced ventricle, including some or all of the following aspects. For example, increasing a ventricular pacing rate a nominal amount to an overdrive pacing rate higher than a most recent heart rate and evaluating a conduction interval from a first pacing ventricle to a second sensing ventricle and then continuing to monitor the underlying rate to ensure that a threshold testing pacing rate will not exceed a predetermined minimum interval and providing pacing stimulation to the first ventricle and sensing the second ventricle to determine whether the pacing stimulation to the first ventricle was one of sub-threshold and supra-threshold. The methods and apparatus are especially useful in conjunction with ensuring actual delivery of a ventricular pacing regime (e.g., cardiac resynchronization therapy or “CRT”).
    Type: Application
    Filed: December 20, 2005
    Publication date: July 6, 2006
    Inventors: Purvee Parikh, John Stroebel, Todd Sheldon, Karen Kleckner
  • Publication number: 20060009811
    Abstract: Techniques for detection and treatment of myocardial ischemia are described that monitor both the electrical and dynamic mechanical activity of the heart to detect and verify the occurrence of myocardial ischemia in a more reliable manner. The occurrence of myocardial ischemia can be detected by monitoring changes in an electrical signal such as an ECG or EGM, and changes in dynamic mechanical activity of the heart. Dynamic mechanical activity can be represented, for example, by a heart acceleration signal or pressure signal. The electrical signal can be obtained from a set of implanted or external electrodes. The heart acceleration signal can be obtained from an accelerometer or pressure sensor deployed within or near the heart. The techniques correlate contractility changes detected by an accelerometer or pressure sensor with changes in the ST electrogram segment detected by the electrodes to increase the reliability of ischemia detection.
    Type: Application
    Filed: August 30, 2005
    Publication date: January 12, 2006
    Inventors: Todd Sheldon, Lee Stylos, Shannon Nelson, Robert Stadler
  • Publication number: 20050203579
    Abstract: A system and automated method for assessing ventricular synchrony in ambulatory patients is provided including at least one mechanical sensor (e.g., accelerometer, tensiometric sensor, force transducer, and the like) operatively coupled to a first myocardial location in order to measure a wall motion signal of a first chamber, and a second mechanical sensor operatively coupled to a second myocardial location in order to measure a wall motion signal of a second chamber. The wall motion signals are processed in order to identify the time at which a fiducial (e.g., an inflection point, a threshold crossing, a maximum amplitude, etc.) occurs for each respective signal. The temporal separation between the fiducial points on each respective signal is measured as a metric of ventricular synchrony and can be optionally utilized to adjust pacing therapy timing to improve synchrony.
    Type: Application
    Filed: March 12, 2004
    Publication date: September 15, 2005
    Inventors: Sameh Sowelam, Todd Sheldon, Yong Cho
  • Publication number: 20050148897
    Abstract: An implantable medical device (IMD) includes a sensor for monitoring parameters indicative of sleep disordered breathing. The IMD also includes a position sensor that indicates the relative position and/or activity level of the patient. The position sensor data is used in one or more ways in conjunction with the SDB sensing. The position data is used to confirm that such sensed data is likely indicative of SDB or to select the appropriate criteria for comparison.
    Type: Application
    Filed: December 24, 2003
    Publication date: July 7, 2005
    Inventors: Yong Cho, Eduardo Warman, Todd Sheldon
  • Publication number: 20050119711
    Abstract: The present invention relates to a device and method for monitoring for sleep disordered breathing or other types of disordered breathing such as Cheyne-Stokes breathing. More specifically, a device and method for detecting disordered breathing is provided that monitors a physiological parameter, which becomes cyclical due to apnea-hyperpnea (or arousal) alternation and provides the basis for the determination of a number of breathing disorder metrics.
    Type: Application
    Filed: April 21, 2003
    Publication date: June 2, 2005
    Inventors: Yong Cho, Abed Lawabni, Todd Sheldon, H. Markowitz, Sameh Sowelam, Raylene Pitschneider
  • Publication number: 20050027320
    Abstract: The present invention relates to monitoring septal wall motion of the atrial and/or ventricular chambers of a heart for optimizing cardiac pacing intervals based on signals derived from said wall motion. At least one lead of medical device is equipped with a motion sensor adapted to couple to septal tissue. The device receives and may post-process (e.g., suitably filter, rectify and/or integrate) motion signals to determine acceleration, velocity or displacement. During pacing interval optimization the wall motion is measured for many pacing intervals and the pacing interval setting(s) that produce minimal wall motion are implemented for therapy delivery. In addition, the present invention provides methods for periodically determining whether to cease or resume delivery of a bi-ventricular pacing therapy to a patient that may have experienced beneficial reverse remodeling of the heart.
    Type: Application
    Filed: July 30, 2003
    Publication date: February 3, 2005
    Inventors: Robert Nehls, Todd Sheldon
  • Publication number: 20050021095
    Abstract: In an atrial pacing system, the A-PACE pulse energy, defined by the pulse width and pulse amplitude, sufficient to reliably capture the atrium without being wasteful of battery energy is periodically determined in accordance with atrial capture management (ACM) algorithms. The ACM algorithms allow a slow intrinsic atrial heart rate that is suppressed by delivered A-PACE pulses resulting in A-CAPTURE and that occurs when delivered test A-PACE pulses result in ALOC to be detected. ALOC is declared if an A-EVENT of the slow intrinsic atrial heart rate is detected either during an ACM test window timed from the last delivered test A-PACE pulse or during delivery of a sequence of test A-PACE pulses delivered within or defining the ACM test window correlated to the slow intrinsic atrial heart rate.
    Type: Application
    Filed: July 23, 2003
    Publication date: January 27, 2005
    Inventors: John Rueter, Todd Sheldon