05271395 is referenced by 142 patents and cites 12 patents.

A rate-responsive cardiac pacemaker comprising a minute ventilation circuit and an activity circuit. The minute ventilation circuit computes a first target pacing rate as a function of measurements of the patient's pleural blood impedance, and the activity circuit computes a second target pacing rate as a function of measured levels of patient activity. A rate control function establishes a rate-responsive pacing rate based on the first and second target pacing rates. The minute ventilation circuit delta-modulates an analog impedance waveform and maintains short-term and long-term weighted averages of delta-modulator output counts. Variations in the difference between the short-term and long-term weighted average values are determinative of the first target pacing rate. Variations in an activity sensor output signal are determinative of the second target pacing rate. Physician-programmable parameters for the pacemaker include selection of a rate-response setting, upper and lower pacing rate limits, and rate-smoothing attack and decay settings.

Title
Method and apparatus for rate-responsive cardiac pacing
Application Number
7/870062
Publication Number
5271395
Application Date
April 17, 1992
Publication Date
December 21, 1993
Inventor
Daniel J Baxter
St. Paul
MN, US
Daniel R Greeninger
Coon Rapids
MN, US
Girard B Borgerding
Minneapolis
MN, US
John D Wahlstrand
Shoreview
MN, US
Agent
Harold R Patton
Dwight N Holmbo
Assignee
Medtronic
MN, US
IPC
A61N 1/362
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