04120307 is referenced by 18 patents and cites 5 patents.

Apparatus for indicating end of battery life in a cardiac pacemaker. A battery voltage monitoring circuit provides an indication of battery voltage drop below a predetermined level. A counter circuit and decode logic respond to the voltage drop indication to block a portion of a predetermined number of the generated pacing pulses from the heart to induce a benign arrhythmia in the heart thereby indicating end of battery life. In another embodiment a plurality of voltage sensors indicate progressive decreases in battery voltage and are connected with decode logic to block an increasing number of pacing pulses to indicate worsening battery condition.

Title
Cardiac pacemaker
Application Number
5/735632
Publication Number
4120307
Application Date
October 26, 1976
Publication Date
October 17, 1978
Inventor
Pieter M J Mulier
St. Paul
MN, US
Thomas L Jirak
Plymouth
MN, US
Agent
Wayne A Sivertson
Assignee
Medtronic
MN, US
IPC
A61N 1/36
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