| 摘要 |
A multispeed 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 information from the two pairs of leads is provided simultaneously on a single oscilloscope tube as one trace above the other, either in real time or at a high speed multiple as a superimposed ECG presentation, or superimposed on each other so as to provide superimposition of the already superimposed ECG signals. An arrhythmia bar graph is also represented on the CRT tube. The playback is in real time, or at multiple high speed playback speeds of 30, 60 and 120 times real time. The playback amplifiers have specific amplitude and frequency responses which are logically switched upon the selection of a particular playback speed to provide accuracy in the reproduced ECG information. A variable tapedeck delay loop is used in combination with two spaced playback heads to provide for a variable reaction time in switching from a high speed imposed presentation of ECG complexes to a real time reproduction to provide for writeout on a paper writer of the previously viewed superimposed ECG complexes. A digital clock using an optical encoder provides a visual presentation of time of day of recording. A programmed tape tension mechanism insures the driving of the optical encoder without slippage during rapid accelerations and decelerations of the magnetic tape. The start time of the digital display of the clock is preset to match the start time of day for the previously recorded information on the tape. The digital clock provides time synchronization of processed data for use by external devices. A heartbeat totalizer provides digital display of the number of heartbeats recorded on the magnetic tape on either an hour-by-hour basis or a cumulative basis. An arrhythmia computer detects and digitally displays the number of premature ventricular contractions (PVC) and supraventricular ectopic beats (SVT), and actuates event markers on a paper writer when the arrhythmia occurrences exceed a preselected number of occurrences during a predetermined time interval. A multispeed, multichannel, paper writer reproduces analog trend data, digital printed data and event marking. The trend information is heart rate and ST segment level to provide a scanning of an entire 24 hour tape in 12 minutes. The paper writer also displays digitally printed time of day and arrhythmia information. |
