PURPOSE: To permit additional displaying and recording of another information, for example, the one like an alarm, in addition to the two dimensional phenomena which could have been displayed and recorded heretofore on a plane by changing the sizes of recording lines and the contrast of the display.

CONSTITUTION: The electrocardiogram analog signal inputted to an input terminal 21 is stored via an amplifier 22 in a memory 23, and the stored contents are successively applied by a controller 24 to a cathode ray tube 27 via a vertical output amplifier 25. On the other hand, the output of an amplifier 22 is converted to the voltage corresponding to periods by a heart heat detector 28, and is compared with the outputs of reference upper and lower limit signal making circuits 31, 32 by comparators 29, 30. The outputs of the respective comparators 29, 30 are applied via an OR circuit 33 and an amplifier 34 to the grid of a cathode ray tube 27, by which the electrocardiogram graphics are displayed brightly when the periods go out of a prescribed range. Thereby, another information such as alarm is further displayed in addition to the two dimensional phenomena.