Patents by Inventor Allen J. Keel

Allen J. Keel 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: 9687656
    Abstract: Provided herein are implantable systems, and methods for use therewith, for monitoring a patient's arterial blood pressure while a patient's heart is being paced. A signal (e.g., PPG or IPG signal) indicative of changes in arterial blood volume remote from the patient's heart is obtained using a sensor or electrodes that are implanted remote from the patient's heart. One or more metrics indicative of pulse arrival time (PAT) are determined, where each metric can be determined by determining a time from a paced cardiac event to one or more predetermined features of the signal indicative of changes in arterial blood volume. Based on at the metric(s) indicative of PAT, arterial blood pressure is estimated, which can include determining values indicative of systolic blood pressure, diastolic blood pressure, pulse pressure and/or mean arterial blood pressure, and/or changes in such values.
    Type: Grant
    Filed: December 14, 2009
    Date of Patent: June 27, 2017
    Assignee: Pacesetter, Inc.
    Inventors: Brian Jeffrey Wenzel, Timothy A. Fayram, Allen J. Keel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi
  • Patent number: 9554717
    Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to monitor and treat heart failure (HF). Such implantable systems preferably includes a lead having at least two electrodes implantable in a patient's left ventricular (LV) chamber. A plurality of different sensing vectors are used to obtain a plurality of IEGMs each of which is indicative of an evoked response at a corresponding different region of the LV chamber. For each of the IEGMs, there is a determination of one or more evoked response metrics indicative of a localized cardiac function at the corresponding region of the LV chamber. The evoke response metrics can be, e.g., paced depolarization integral (PDI) and/or maximum upward slope of an R-wave, but are not limited thereto.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: January 31, 2017
    Assignee: Pacesetter, Inc.
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Patent number: 9002453
    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.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: April 7, 2015
    Assignee: Pacesetter, Inc.
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Patent number: 8798731
    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.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: August 5, 2014
    Assignee: Pacesetter, Inc.
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Patent number: 8509890
    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 patients 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.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: August 13, 2013
    Assignee: Pacesetter, Inc.
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Patent number: 8428698
    Abstract: Implantable systems, and methods for use therewith, are provided for monitoring a patient's diastolic function and/or heart failure (HF) condition. A signal indicative of changes in arterial blood volume and a signal indicative of electrical activity of the patient's heart are obtained. Beginnings of diastolic periods can be detected based on a feature of the signal indicative of changes in arterial blood volume. Ends of the diastolic periods can be detected based on a feature of the signal indicative of electrical activity of the patient's heart, or on the signal indicative of changes in arterial blood volume. Diastolic periods (DPs), isovolumic relaxation times (IVRTs) and/or diastolic filling times (DiFTs) can be estimated based on the detected beginnings of the diastolic periods and detected ends of the diastolic periods. The patient's diastolic function and/or HF condition (and/or changes therein) can be monitored based on the estimates of DP, IVRT and/or DiFT.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: April 23, 2013
    Assignee: Pacesetter, Inc.
    Inventors: Allen J. Keel, Brian Jeffrey Wenzel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi
  • Publication number: 20130030487
    Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to increase compliance with a predetermined preferred ventricular electrical activation pattern. Such implantable systems preferably includes a first lead having at least one electrode implantable in a right ventricular (RV) chamber, and a second lead having at least two electrodes implantable in a left ventricular (LV) chamber. A plurality of different sensing vectors are used to obtain a plurality of IEGMs that collectively enable electrical activations to be detected in at least the RV chamber and at at least two separate regions of the LV chamber. The IEGMs can be obtained while the patient's LV chamber is not being paced, or during bi-ventricular (BiV) pacing that includes pacing at only a single site within the LV chamber. An actual ventricular electrical activation pattern is determined based on the plurality of IEGMs.
    Type: Application
    Filed: July 29, 2011
    Publication date: January 31, 2013
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Publication number: 20130030314
    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.
    Type: Application
    Filed: July 29, 2011
    Publication date: January 31, 2013
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenburg
  • Publication number: 20130030312
    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.
    Type: Application
    Filed: July 29, 2011
    Publication date: January 31, 2013
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Publication number: 20130030315
    Abstract: Described herein are implantable systems and devices, and methods for use therewith, that can be used to monitor and treat heart failure (HF). Such implantable systems preferably includes a lead having at least two electrodes implantable in a patient's left ventricular (LV) chamber. A plurality of different sensing vectors are used to obtain a plurality of IEGMs each of which is indicative of an evoked response at a corresponding different region of the LV chamber. For each of the IEGMs, there is a determination of one or more evoked response metrics indicative of a localized cardiac function at the corresponding region of the LV chamber. The evoke response metrics can be, e.g., paced depolarization integral (PDI) and/or maximum upward slope of an R-wave, but are not limited thereto.
    Type: Application
    Filed: July 29, 2011
    Publication date: January 31, 2013
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenburg
  • Publication number: 20130006317
    Abstract: Described herein are implantable systems, and methods for use therewith, to predict whether ventricular tachycardia (VT) or ventricular fibrillation (VF) is imminent, estimate ischemic burden and/or characterize an electrical substrate of the LV chamber. For each of a plurality of cardiac cycles, a pacing vector comprising a first set of electrodes is used to deliver a pre-pacing pulse at a site within the LV chamber (wherein the pre-pacing pulse is delivered prior to an intrinsic activation of the LV chamber), and a sensing vector comprising a second set of electrodes is used to detect an evoked response to the pre-pacing pulse. The detected evoked responses to the pre-pacing pulses are analyzed, and results of the analysis are used predict whether VT or VF is imminent, estimate ischemic burden and/or characterize an electrical substrate of the LV chamber.
    Type: Application
    Filed: June 30, 2011
    Publication date: January 3, 2013
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg, Kiell Norén
  • Patent number: 8321017
    Abstract: Implantable systems, and methods for use therewith, enable the monitoring of a patient's electromechanical delay (EMD) and arterial blood pressure. Paced cardiac events are caused by delivering sufficient pacing stimulation to cause capture. A cardiogenic impedance (CI) signal, indicative of cardiac contractile activity in response to the pacing stimulation being delivered, is obtained. One or more predetermined features of the CI signal are detected, and a value indicative of the patient's EMD is determined by determining a time between a delivered pacing stimulation and at least one of the detected one or more features of the CI signal. The value indicative of EMD can be used to more accurately determine metrics indicative of pulse arrival time (PAT), which can be used to estimate arterial blood pressure.
    Type: Grant
    Filed: December 14, 2009
    Date of Patent: November 27, 2012
    Assignee: Pacesetter, Inc.
    Inventors: Brian Jeffrey Wenzel, Timothy A. Fayram, Allen J. Keel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi
  • Publication number: 20120271371
    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 patients 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.
    Type: Application
    Filed: April 21, 2011
    Publication date: October 25, 2012
    Inventors: Allen J. Keel, Kyungmoo Ryu, Stuart Rosenberg
  • Patent number: 8162841
    Abstract: Certain embodiments of the present invention are related to an implantable monitoring device to monitor a patient's arterial blood pressure, where the device is configured to be implanted subcutaneously. The device includes subcutaneous (SubQ) electrodes and a plethysmography sensor. Additionally, the device includes an arterial blood pressure monitor configured to determine at least one value indicative of the patient's arterial blood pressure based on at least one detected predetermined feature of a SubQ ECG and at least one detected predetermined feature of a plethysmography signal. Alternative embodiments of the present invention are directed to a non-implantable monitoring device to monitor a patient's arterial blood pressure based on features of a surface ECG and a plethysmography signal obtained from a non-implanted sensor.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: April 24, 2012
    Assignee: Pacesetter, Inc.
    Inventors: Allen J. Keel, Brian Jeffrey Wenzel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi, Timothy A. Fayram, Eric S. Fain, Paul A. Levine
  • Publication number: 20110125208
    Abstract: An implanted sensor produces a signal that is indicative of changes in arterial blood volume, such as a photoplethysmography signal or an impedance plethysmography signal. A metric is determined from the signal for each of the plurality of periods. Changes in cardiac contractility are monitored based on changes in the determined metric.
    Type: Application
    Filed: December 30, 2009
    Publication date: May 26, 2011
    Inventors: Edward Karst, Brian Jeffrey Wenzel, Allen J. Keel, Wenbo Hou, Taraneh Ghaffari Farazi
  • Publication number: 20110040345
    Abstract: Provided herein are implantable systems, and methods for use therewith, for monitoring a patient's electromechanical delay (EMD). Paced cardiac events are caused by delivering sufficient pacing stimulation to cause capture to the patient's heart. A cardiogenic impedance (CI) signal, indicative of cardiac contractile activity in response to the pacing stimulation being delivered, is obtained. One or more predetermined features of the CI signal are detected, and a value indicative of the patient's EMD is determined by determining a time between a delivered pacing stimulation and at least one of the detected one or more features of the CI signal.
    Type: Application
    Filed: December 14, 2009
    Publication date: February 17, 2011
    Inventors: Brian Jeffrey Wenzel, Timothy A. Fayram, Allen J. Keel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi
  • Publication number: 20110009755
    Abstract: Provided herein are implantable systems, and methods for use therewith, for monitoring a patient's arterial blood pressure while a patient's heart is being paced. A signal (e.g., PPG or IPG signal) indicative of changes in arterial blood volume remote from the patient's heart is obtained using a sensor or electrodes that are implanted remote from the patient's heart. One or more metrics indicative of pulse arrival time (PAT) are determined, where each metric can be determined by determining a time from a paced cardiac event to one or more predetermined features of the signal indicative of changes in arterial blood volume. Based on at the metric(s) indicative of PAT, arterial blood pressure is estimated, which can include determining values indicative of systolic blood pressure, diastolic blood pressure, pulse pressure and/or mean arterial blood pressure, and/or changes in such values.
    Type: Application
    Filed: December 14, 2009
    Publication date: January 13, 2011
    Inventors: Brian Jeffrey Wenzel, Timothy A. Fayram, Allen J. Keel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi
  • Publication number: 20110009754
    Abstract: Provided herein are implantable systems, and methods for use therewith, for monitoring a patient's arterial blood pressure. Electrode(s) implanting within and/or on the patient's heart are used to obtain a cardiogenic impedance (CI) signal indicative of cardiac contractile activity. Additionally, a signal (e.g., PPG or IPG signal) indicative of changes in arterial blood volume remote from the patient's heart is obtained using a sensor or electrodes that are implanted remote from the patient's heart. One or more metrics indicative of pulse arrival time (PAT) are determined, where each metric can be determined by determining a time from one of the detected features of the CI signal to one of the detected features of the signal indicative of changes in arterial blood volume.
    Type: Application
    Filed: December 14, 2009
    Publication date: January 13, 2011
    Inventors: Brian Jeffrey Wenzel, Allen J. Keel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi, Gene A. Bornzin
  • Publication number: 20100312128
    Abstract: Methods and systems for monitoring an organ of interest within a patient use one or more sensors to obtain one or more signals indicative of one or more of blood being provided to the organ of interest, blood being received from the organ of interest, and blood present in the organ of interest. Changes in an amount of blood being provided to the organ of interest, an amount of blood being received from the organ of interest, and/or an amount of blood present in the organ of interest are monitored based on changes in the obtained signal(s). Such methods and systems can be used to detect dysfunction of the organ of interest or tumor growth in the organ of interest, but are not limited thereto.
    Type: Application
    Filed: December 29, 2009
    Publication date: December 9, 2010
    Inventors: Edward Karst, Brian Jeffrey Wenzel, Allen J. Keel, Wenbo Hou, Taraneh Ghaffari Farazi
  • Publication number: 20100228136
    Abstract: Implantable systems, and methods for use therewith, are provided for monitoring a patient's diastolic function and/or heart failure (HF) condition. A signal indicative of changes in arterial blood volume and a signal indicative of electrical activity of the patient's heart are obtained. Beginnings of diastolic periods can be detected based on a feature of the signal indicative of changes in arterial blood volume. Ends of the diastolic periods can be detected based on a feature of the signal indicative of electrical activity of the patient's heart, or on the signal indicative of changes in arterial blood volume. Diastolic periods (DPs), isovolumic relaxation times (IVRTs) and/or diastolic filling times (DiFTs) can be estimated based on the detected beginnings of the diastolic periods and detected ends of the diastolic periods. The patient's diastolic function and/or HF condition (and/or changes therein) can be monitored based on the estimates of DP, IVRT and/or DiFT.
    Type: Application
    Filed: May 29, 2009
    Publication date: September 9, 2010
    Inventors: Allen J. Keel, Brian Jeffrey Wenzel, Edward Karst, Wenbo Hou, Taraneh Ghaffari Farazi