04291699 is referenced by 156 patents and cites 4 patents.

Method of and apparatus for automatic defibrillation of the cardiac ventricles of a heart wherein both the mechanical and electrical activities of the ventricles are sensed and used as operating inputs to the controls. Electrical activity is detected and measured with a pair of electrodes, and the waves of an electrocardiogram (ECG) are analyzed. When such electrical analysis indicates that ventricular fibrillation is present and persists, an electrical circuit is actuated for detecting mechanical pumping activity of the heart. Mechanical pumping activity is measured by the change in impedance between the pair of electrodes in one of the ventricles. The change of ventricular impedance is caused by the varying volume of blood contained within the ventricle and depends upon whether the ventricle is in a contracted or a relaxed state. The defibrillator is actuated only when both the mechanical and electrical activity of the ventricle indicates a need for defibrillation. Because some conditions may be encountered which closely resemble ventricular fibrillation, the defibrillator quantitatively preprograms and weighs the relative importance of the electrical and mechanical signals from the heart.

Title
Method of and apparatus for automatically detecting and treating ventricular fibrillation
Application Number
5/944369
Publication Number
4291699
Application Date
September 21, 1978
Publication Date
September 29, 1981
Inventor
Reese S Terry
Freeport
TX, US
Joe D Bourland
West Lafayette
IN, US
Leslie A Geddes
West Lafayette
IN, US
Agent
John A Young
Larry J Palguta
Assignee
Purdue Research Foundation
IN, US
IPC
A61N 1/36
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