Sphygmomanometer main body and sphygmomanometer

A method for measuring an electrocardiogram waveform of a subject by using a sphygmomanometer having a sphygmomanometer main body, the sphygmomanometer main body comprising:

• a housing configured to be placed on a table, the housing comprising:
• a bottom surface to face the table,
• an upper surface positioned opposite to the bottom surface,
• a front surface extending from the bottom surface to the upper surface on a front side of the housing,
• a back surface extending from the bottom surface to the upper surface on a back side of the housing, and
• a pair of a first side surface and a second side surface extending from the bottom surface to the upper surface on left and right sides of the housing, wherein
• the upper surface has an upward inclination to be higher toward the back surface from the front surface,
• the upper surface is delimited, by a step, into a terminal placement portion occupying a region separated from the front surface with respect to a direction along the upward inclination and a rest portion other than the terminal placement portion, the terminal placement portion extending flatly along the upward inclination and having a predetermined size and shape for a portable information terminal including a display to be placed,
• the step lowers from the rest portion to the terminal placement portion and has a U-shaped configuration that surrounds a front side, a left side, and a right side of the terminal placement portion and not a back side of the terminal placement portion, such that the terminal placement portion is open upward and backward,
• the first side surface is provided with a first electrode configured to measure a potential with the first electrode touched by one of second to fifth fingers of one hand of the subject,
• the second side surface is provided with a second electrode configured to measure a potential with the second electrode touched by one of second to fifth fingers of the other hand of the subject,
• a first region of the upper surface positioned closer to the first side surface than the second side surface is provided with a third electrode configured to measure a potential with the third electrode touched by a first finger of the one hand of the subject,
• a second region of the upper surface positioned closer to the second side surface than the first side surface is provided with a fourth electrode configured to measure a potential with the fourth electrode touched by a first finger of the other hand of the subject,
• an electrocardiogram waveform measurement circuit is provided inside the housing,
• the electrocardiogram waveform measurement circuit is configured to obtain electrocardiogram waveform information representing an electrocardiogram waveform from a potential difference between the potential input to the first electrode and the potential input to the third electrode, or a potential difference between the potential input to the second electrode and the potential input to the fourth electrode,
• the first side surface has a first height equal to or greater than a combined width of the second to fifth fingers of the one hand of the subject, and extends in a front and rear direction for a first length longer than all of the second to fifth fingers of the one hand of the subject, and
• the second side surface has a second height equal to or greater than a combined width of the second to fifth fingers of the other hand of the subject, and extends in the front and rear direction for a second length longer than all of the second to fifth fingers of the other hand of the subject, wherein the method comprises:
• in a state where the housing is placed on the table,
• touching the first electrode by the one of the second to fifth fingers of the one hand of the subject, placing the fifth finger of the one hand of the subject on the table, and extending all of the second to fifth fingers of the one hand of the subject in the front and rear direction along the first side surface, and
• touching the second electrode by the one of the second to fifth fingers of the other hand of the subject, placing the fifth finger of the other hand of the subject on the table, and extending all of the second to fifth fingers of the other hand of the subject in the front and rear direction along the second side surface, and then
• obtaining, by the electrocardiogram waveform measurement circuit, the electrocardiogram waveform information representing the electrocardiogram waveform from a potential difference between the potential input to the first electrode and the potential input to the third electrode, or a potential difference between the potential input to the second electrode and the potential input to the fourth electrode.