Patent ID: RE38680

Claim:
A system for determining the heart rate and for detecting a medical condition of a heart, comprising: an electrode for sensing heart action signals; an input stage connected to the electrode for processing the heart action signals; a refractory member for ascertaining a refractory time of the system after a predetermined segment of a heart action signal, said refractory member connected to an output of the input stage; a processing device connected to an output of the input stage for determining the rate of the heart action signals which includes a means responsive to the refractory member for processing the heart action signals by blanking a component of a heart action signal that occurs during the refractory time, and a counter of detected heart signals for determining the heart rate; and adjusting means connected between an output of the processing device and said refractory member for automatically adjusting the refractory time of the refractory member which includes an arithmetic calculation unit for calculating the refractory time (T ref ) as a function of a previously determined value of the heart rate in accordance with the following equation (1): T ref =QT=QTc−1.75(T n −60) T ref =QT=QTc− 1 . 75 ( T RR − 60 ) (1) wherein T ref is the refractory period, T rr is the previously calculated refractory period T RR is the time period between adjacent R - peaks of a heart action signal , and QTc is a set period.