Raymond E Wilson

US Patent:

58107398, Sep 22, 1998

Filed:

Dec 19, 1996

Appl. No.:

8/770767

Inventors:

Gene A. Bornzin - Simi Valley CA
Alan B. Vogel - Saugus CA
Ali Enayat Zadeh - Sierra Madre CA
Jonathan A. Kleks - Los Altos CA
Raymond J. Wilson - Parker CO

Assignee:

Pacesetter, Inc. - Sylmar CA

International Classification:

A61N 50452

US Classification:

600510

Abstract:

Methods and apparatus are provided for classifying cardiac events with an implantable cardiac device. Cardiac signals are stored in a buffer. When a significant cardiac event is confirmed, a corresponding segment of the stored cardiac signals is processed to generate a set of feature values. The set of feature values is compared to various sets of reference values. Each set of reference values preferably corresponds to a separate type of cardiac event, so that the cardiac device may classify the significant cardiac event by matching its set of feature values to a set of reference values. Feature values include the maximum positive and negative slew rates exhibited by the cardiac signal during the segment, the maximum positive and negative signal amplitudes, the times to reach the maximum positive and negative signal amplitudes, the area under the cardiac signal curve, the area under the cardiac signal curve above zero as compared to the area below zero, and the number of zero crossings made by the cardiac signal. Additional feature values are generated by simultaneously processing the cardiac signals measured along two different vector directions in the heart.

US Patent:

59083921, Jun 1, 1999

Filed:

Mar 13, 1996

Appl. No.:

8/596895

Inventors:

Raymond J. Wilson - Parker CO
Laurence S. Sloman - West Hollywood CA

Assignee:

Pacesetter, Inc. - Sylmar CA

International Classification:

A61B 50452

US Classification:

600509

Abstract:

The system of the present invention records and stores, in long-term memory and in form of data snapshots, medical data acquired prior to and subsequent to an occurrence of cardiac episodes and implantable device functions defined as important by the medical practitioner. The system provides the medical practitioner with the ability to specify trigger criteria representative of important cardiac episodes and implantable device functions. The system of the present invention allows the medical practitioner to control the amount of medical data stored in the data snapshots. The system allows the medical practitioner to specify a mode of storing data snapshots when the maximum storage capacity of long-term memory has been reached. In a first mode, the system stores data snapshots in a circular buffer manner, overwriting the older data snapshots. In a second mode, the system stops storing new data snapshots after the maximum storage capacity of long-term memory has been reached.