Cardiac arrhythmia detector and recorder

Abstract From the Canadian patent

Cardiac arrhythmias are detected by measuring the duration of the first derivative of the QRS component signal of a cardiac rhythm and comparing such duration to a running average duration, and/or by measuring the duration of the R-R interval and comparing such interval to a running average interval. A cassette recorder is activated in response to an arrhythmia detected by either one of the above techniques. The cardiac rhythm signal is fed to the recorder through a delay network such that the recorded signal brackets the detected arrhythmia. A manual record switch is also provided for separate wearer actuation to record what he considers to be unusual heart activity. -o-