Electrocardiographic computer

Abstract

A multi-speed ECG magnetic tape scanning device for processing and observing in a relatively short interval of time large quantities of ECG signals from two pairs of ECG leads. The ECG information is recorded on a miniature recorder which the patient carries to record the information for a long period of time, such as 24 hours. The recorder includes a built-in clock with a visible display. The recorder also includes an event marker, which is activated by the patient when the patient experiences an event. The play-back of the ECG information is in real time or at multiple high speed play-back speeds of 30, 60 and 120 times real time. During play-back at high speed, a multi-speed multi-channel paper writer reproduces analog trend data, digital printed data and event marking. The trend information is usually heart rate and ST segment level, so as to produce a scanning of an entire 24 hour information tape in as short a period as 12 minutes. The tape scanning device can run on trend to print out trend to the end of the tape, and then stop automatically. Alternatively, the tape scanning device can run on trend to the end of the tape and then automatically cycle to the beginning of the tape to print-out trend and periodically slow the tape down to real time for the print-out of predetermined events in real time. After each print-out in real time, the playback always goes back to the originally selected trend speed for the continuation of the trend print-out. Various short events may be used to slow the read-out to real time, such as an event marking on the tape which has been activated by the patient. Also, any preselected abnormalities in heart function such as abnormal VE's, SVE's, ST level, rapid heart beat, slow heart rate, etc., may be used to print-out in real time. An arrhythmia computer detects and digitally displays the number of premature ventricular contractions (VE) and superventricular ectopic beats (SVE) and actuates the event markers on a paper writer when the arrhythmia occurrences exceed a predetermined number of occurrences during a predetermined time interval. The event marking may also be used to control the slow down during trend read-out to print out the ECG signals in real time to show the arrhythmia occurrences. The arrhythmia computer includes the ability to select one or a number of parameters to determine the occurrence of an arrhythmia. These parameters may be paired beats, prematurity, width or amplitude.