Douglas A Hettrick

US Patent:

7065398, Jun 20, 2006

Filed:

Sep 30, 2002

Appl. No.:

10/260845

Inventors:

Douglas A. Hettrick - Blaine MN, US
Jacqueline Mittelstadt - Milwaukee WI, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61B 5/452

US Classification:

600515

Abstract:

Techniques for preventing inadvertent detection of AT termination may involve predicting potential undersensing of atrial events, and delaying detection of AT termination when undersensing of atrial events is predicted. For example, an implantable medical device may measure ventricular-atrial (VA) intervals of a heart rhythm using tracked atrial and ventricular events. The device calculates a slope of the series of the VA intervals, and estimates a prospective VA interval using the calculated slope and the most recently measured VA interval. The device determines whether the estimated VA interval is within a threshold range. When the estimated VA interval is outside of the threshold range, the device predicts possible undersensing of atrial events and delays detection of the AT episode termination. The delay detection of AT episode termination improves the accuracy of information collected by event counters.

US Patent:

7127292, Oct 24, 2006

Filed:

Oct 31, 2002

Appl. No.:

10/284873

Inventors:

Eduardo N. Warman - Maple Grove MN, US
Stefan Holzer - Vienna, AT
Helmut Puererfellner - Engerwitzdorf, AT
Douglas A. Hettrick - Blaine MN, US
Paul D. Ziegler - Minneapolis MN, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61N 1/36
A61N 1/365

US Classification:

607 25, 607 4, 607 14, 607 17

Abstract:

An implantable medical device is directed to techniques for applying overdrive pacing to one or both atria following termination of an AF episode, to prevent a recurrent AF episode. The implantable medical device such as a pacemaker applies overdrive pacing according to overdrive pacing parameters, and sets the parameters as a function of the response of the patient to overdrive pacing. The parameters may be adjusted upward or downward, so that overdrive pacing may be applied effectively but not over-applied.

US Patent:

7181283, Feb 20, 2007

Filed:

Mar 31, 2005

Appl. No.:

11/097408

Inventors:

Douglas A. Hettrick - Blaine MN, US
Todd M. Zielinski - Minneapolis MN, US
Amber L Jaeger - West Bend WI, US
Nicole M. Campbell - Milwaukee WI, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61N 1/365
A61B 5/021

US Classification:

607 23, 607 18, 607 17, 600485, 600486

Abstract:

In an implantable medical device a real-time left atrial pressure (“LAP”) signal obtained from a patient's heart is used as a feedback control mechanism to adjust one or more device parameters. In one example the device identifies specific characteristics and attributes of the LAP signal that correlate to hemodynamic performance, and adjusts the device parameters to optimize the LAP characteristics and attributes. In a dual-chamber pacing system, the controlled operating parameter may include the atrioventricular pacing delay, and LAP attribute suitable for controlling the atrioventricular pacing delay time intervals of v-wave, a-wave, and/or c-wave characteristics of the LAP signal.

US Patent:

7233821, Jun 19, 2007

Filed:

Mar 31, 2005

Appl. No.:

11/097706

Inventors:

Douglas A. Hettrick - Blaine MN, US
David E. Euler - Maple Grove MN, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61B 5/02
A61B 5/04
A61N 1/00

US Classification:

600510, 600508, 600509, 607 9, 607 14, 607119

Abstract:

A method of evaluating ventricular performance of a heart employing sensors to measure a ventricular dimension signal and deriving indices of ventricular performance therefrom. Premature Shortening (PS) and Isovolumic Lengthening (IL) comprise two indices of ventricular performance determined from analysis of the left ventricular dimension signal during the transition from ventricular filling to ventricular ejection. Measured values of PS and IL are compared to other measured values or reference values to determine if ventricular performance has improved (or worsened). In some embodiments, the dimension sensors may comprise piezoelectric sonomicrometer crystals that operate as ultrasound transmitters and receivers. The sensors may be mounted in relation to a ventricle of the heart either temporarily or permanently, and may be configured either separately from or integrally with cardiac pacing leads.

US Patent:

7233822, Jun 19, 2007

Filed:

Jun 29, 2004

Appl. No.:

10/881541

Inventors:

Douglas A. Hettrick - Blaine MN, US
David E. Euler - Maple Grove MN, US
Mark L Brown - North Oaks MN, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61B 5/04

US Classification:

600515, 600518

Abstract:

A system and method for detecting and classifying cardiac arrhythmias based on cardiac pressure signals or the combination of cardiac electrical and cardiac pressure signals. A cardiac electrogram signal is sensed to derive a cardiac rate from which an arrhythmia detection is made when the cardiac rate meets arrhythmia detection criteria. An intracardiac pressure signal is sensed to derive an indicator of tachycardia based on an analysis of the pressure signal in either the time domain or frequency domain. The detected arrhythmia is classified as tachycardia or fibrillation based on the tachycardia indicator wherein the tachycardia indicator is compared to tachycardia detection criteria and the arrhythmia is classified as tachycardia if tachycardia detection criteria are met and the arrhythmia is classified as fibrillation if the tachycardia detection criteria are not met.

US Patent:

7336994, Feb 26, 2008

Filed:

Jan 16, 2004

Appl. No.:

10/760155

Inventors:

Douglas A. Hettrick - Blaine MN, US
David E. Euler - Maple Grove MN, US
Eduardo N. Warman - Maple Grove MN, US
Michael R. Ujhelyi - Maple Grove MN, US
Rahul Mehra - Stillwater MN, US
Paul D. Ziegler - Minneapolis MN, US
Shailesh Kumar V. Musley - Blaine MN, US
Charles E. Distad - St. Paul MN, US
David E. Ritscher - Minneapolis MN, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61N 1/39

US Classification:

607 5, 607 4, 607 6, 607 7

Abstract:

Control of defibrillation therapy delivered by implantable medical devices (IMDs) using hemodynamic sensor feedback is disclosed. The hemodynamic sensor feedback allows for increased control over application of atrial defibrillation therapy. Specifically, the therapy is delivered when a fibrillation episode results in a discrete loss of hemodynamic function. Defibrillation therapy is thus withheld for hemodynamically benign arrhythmias.

US Patent:

7367951, May 6, 2008

Filed:

Jan 27, 2005

Appl. No.:

11/044617

Inventors:

Tommy D. Bennett - Shoreview MN, US
Mark Choi - Minneapolis MN, US
David A. Igel - Lino Lakes MN, US
Michael R. S. Hill - Minneapolis MN, US
Teresa A. Whitman - Dayton MN, US
Douglas A. Hettrick - Andover MN, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61B 5/02

US Classification:

600485, 600500, 600508

Abstract:

A cardiovascular analysis system and method includes an implantable medical device with a sensor positioned to sense a hemodynamic pressure over time. The implantable medical device generates hemodynamic pressure waveform data based upon the hemodynamic pressure sensed. A processor analyzes the hemodynamic waveform data to provide an indication of cardiovascular health based upon prominent peaks in the hemodynamic waveform data.

US Patent:

7502646, Mar 10, 2009

Filed:

Jul 31, 2006

Appl. No.:

11/461141

Inventors:

Todd J. Sheldon - North Oaks MN, US
Scott R. Stanslaski - Shoreview MN, US
Michael O. Sweeney - Chestnut Hill MA, US
Robert A. Betzold - Fridley MN, US
Douglas A. Hettrick - Blaine MN, US
Paul A. Belk - Maple Grove MN, US

Assignee:

Medtronic, Inc. - Minneapolis MN

International Classification:

A61N 1/362

US Classification:

607 9

Abstract:

An implantable medical device operates according to a ventricular pacing protocol (VPP) that precludes ventricular pacing in any cardiac cycle where a sensed ventricular event has occurred in the preceding cycle. Improved ventricular sensing, detection and classification is provided.