Dan M Li

US Patent:

7430446, Sep 30, 2008

Filed:

Jan 20, 2005

Appl. No.:

11/038996

Inventors:

Dan Li - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61B 5/024

US Classification:

600515, 600518

Abstract:

An implantable cardioverter/defibrillator (ICD) includes a tachyarrhythmia detection and classification system that classifies tachyarrhythmias based on a morphological analysis of arrhythmic waveforms and a template waveform. Correlation coefficients each computed between morphological features of an arrhythmic waveform and morphological features of the template waveform provide for the basis for classifying the tachyarrhythmia. In one embodiment, morphological features are collected from a sensed arrhythmic waveform, and temporally corresponding morphological features are extracted a stored template waveform. In one embodiment, a correlation analysis takes into account the uncertainty associated with the production of the template waveform by using a template band that includes confidence intervals. In one embodiment, a correlation analysis produces Mahalanobis distance-based correlation coefficients for use in the classification of the tachyarrhythmia. In one embodiment, the stability of correlation coefficients are analyzed to classify the tachyarrhythmia.

US Patent:

7480529, Jan 20, 2009

Filed:

Jun 13, 2005

Appl. No.:

11/151102

Inventors:

Dan Li - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61B 5/0402
A61B 5/0472

US Classification:

600515, 600516, 600517, 600518

Abstract:

An implantable medical device includes an arrhythmia detection and classification system that classifies an arrhythmia episode based on an irregularity parameter and/or a complexity parameter. The arrhythmia episode is detected from a cardiac signal. The irregularity parameter is indicative of the degree of cycle length irregularity of the cardiac signal and the complexity parameter is indicative of the degree of morphological complexity of the cardiac signal. One example of the irregularity parameter is an irregularity sample entropy, or a parameter related to the irregularity sample entropy, computed to indicate the cycle length irregularity. One example of the complexity parameter is a complexity sample entropy, or a parameter related to the complexity sample entropy, computed to indicate the morphological complexity. In one embodiment, the detected arrhythmia episode is classified using both the irregularity parameter and the complexity parameter.

US Patent:

7572232, Aug 11, 2009

Filed:

Jul 24, 2006

Appl. No.:

11/459588

Inventors:

Dan Li - Shoreview MN, US
Quan Ni - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61B 5/04

US Classification:

600508

Abstract:

A system comprising a medical device including a processor and a Z-score transformation (ZST) module. The system also includes a display in communication with the processor. The processor is adapted to receive sensor data obtained from at least first and second sensors adapted to produce a time-varying physiologic electrical sensor signal. At least one of the first and second sensors is implantable. The ZST module calculates a ZST for the sensor data received from the first sensor and a ZST for the sensor data received from the second sensor. The display is adapted to display the ZSTs in visual correspondence with each other over time.

US Patent:

7582061, Sep 1, 2009

Filed:

Dec 22, 2005

Appl. No.:

11/316332

Inventors:

Dan Li - Shoreview MN, US
Shelley Cazares - Minneapolis MN, US
Jaeho Kim - Redmond WA, US
Kent Lee - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61B 5/02

US Classification:

600508, 600515

Abstract:

A tachyarrhythmia detection and classification system classifies tachyarrhythmias based on an analysis of morphological features of a cardiac signal enhanced by using one or more physiological parameters indicative of hemodynamic stability and/or activity level. The tachyarrhythmia detection and classification system computes a measure of similarity between an arrhythmic waveform of the cardiac signal a template waveform for that cardiac signal, such as a correlation coefficient representative of the correlation between morphological features of the arrhythmic waveform and morphological features of the template waveform. A detected tachyarrhythmia episode is classified by comparing the measure of similarity to a threshold that is dynamically adjusted using the one or more physiological parameters.

US Patent:

7616994, Nov 10, 2009

Filed:

May 24, 2004

Appl. No.:

10/852080

Inventors:

Dan Li - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61N 1/37
A61N 1/08

US Classification:

607 14, 607 4

Abstract:

A method comprising detecting a ventricular tachycardia heart rhythm in a patient, providing anti-tachycardia pacing (ATP) therapy to the patient in response to the ventricular tachycardia heart rhythm, waiting a first time duration after the ATP therapy ends, and monitoring ventricular depolarizations after the first time duration has elapsed. The monitoring includes measuring time intervals between the ventricular depolarizations, and if a consecutive number of the intervals between the ventricular depolarizations are shorter than a first threshold interval value, then the method includes deeming that the ventricular tachycardia rhythm persists. Otherwise, if a fraction of the intervals between the ventricular depolarizations are shorter than a second threshold interval value, then the method includes deeming that the ventricular tachycardia heart rhythm persists, and otherwise deeming that the ventricular tachycardia rhythm is converted.

US Patent:

7761154, Jul 20, 2010

Filed:

Jan 25, 2006

Appl. No.:

11/275696

Inventors:

Dan Li - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61N 1/362

US Classification:

607 14

Abstract:

An implantable medical device delivers anti-tachyarrhythmia therapies including anti-tachyarrhythmia pacing (ATP). When a tachyarrhythmia episode is detected, the implantable medical device analyzes cardiac cycle length stability to determine whether and/or when to deliver an ATP. In one embodiment, the cardiac cycle length stability is measured by existence of stable ventricular tachyarrhythmia clusters (SVTCs) during the tachyarrhythmia episode. Each SVTC includes at least a specified minimum number of heart beats over which the cardiac cycle lengths meet a stability criterion.

US Patent:

7783356, Aug 24, 2010

Filed:

Jun 29, 2006

Appl. No.:

11/427407

Inventors:

Shelley Cazares - Minneapolis MN, US
Dan Li - Shoreview MN, US
Jonathan Kwok - Shoreview MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61N 1/362

US Classification:

607 32, 607 30, 607 31

Abstract:

This document discusses, among other things, methods and systems for facilitating automated device programming at changeout. A method comprises receiving, from a first device, physiological data at a temporary storage device; and processing the received physiological data, wherein the processing includes determining if a first signal processing function was used by the first device and substantially offsetting the first signal processing function if the first signal processing function was used by the first device; and processing the resultant physiological data to be compatible with a second device. The method further comprising providing the processed resultant physiological data to the second device.

US Patent:

7801608, Sep 21, 2010

Filed:

Jun 5, 2006

Appl. No.:

11/422101

Inventors:

Dan Li - Shoreview MN, US
Cheng Zhang - Vadnais Heights MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61N 1/08

US Classification:

607 14, 607 9, 607 23, 600485

Abstract:

A cardiac rhythm management (CRM) system includes an implantable medical device that delivers anti-tachyarrhythmia therapies including anti-tachyarrhythmia pacing (ATP) and a hemodynamic sensor that senses a hemodynamic signal. The implantable medical device includes a hemodynamic sensor-controlled closed-loop ATP system that uses the hemodynamic signal for ATP capture verification. When ATP pulses are delivered according to a selected ATP protocol to terminate a tachyarrhythmia episode, the implantable medical device performs the ATP capture verification by detecting an effective cardiac contraction from the hemodynamic signal. The ATP protocol is adjusted using an outcome of the ATP capture verification.