Pulse wave data analyzing method, system, and program product

A pulse wave data analyzing system for extracting vital information out of pulse wave data concerning a living body, the system comprising:

• a pulse wave detector for obtaining pulse wave information concerning a subject at a predetermined sampling frequency to acquire pulse wave data in association with a time axis;
• and
• a data analyzer for executing a noise removal process to analyze the pulse wave data,
• the data analyzer including:
• an inflection point detector for detecting bottom values and peak values along the time axis in a time-series manner out of the pulse wave data,
• an amplitude value detector for making pairs with respect to the bottom values and the peak values adjacent to each other on the time axis to obtain bottom-to-peak amplitude values along the time axis, the bottom-to-peak amplitude values being a difference between the bottom value and the peak value in each of the pairs,
• a noise remover for comparing each set of two bottom-to-peak amplitude values adjacent to each other along the time axis to remove the bottom value and the peak value relating to the smaller bottom-to-peak amplitude value in each set as noise, if a ratio of one of the two bottom-to-peak amplitude values to the other one of the two bottom-to-peak amplitude values is larger than a predetermined value, and
• an interval calculator for obtaining peak-to-peak intervals or bottom-to-bottom intervals corresponding to electrocardiogram RR-intervals based on pulse wave data obtained by executing the noise removal by the noise remover.

A pulse wave data analyzing program product for extracting vital information out of pulse wave data concerning a living body, the program product comprising:

• a program which causes a data analyzer for analyzing the pulse wave data to execute steps for:
• obtaining pulse wave information concerning a subject at a predetermined sampling frequency to acquire pulse wave data in association with a time axis;
• detecting bottom values and peak values along the time axis in a time-series manner out of the pulse wave data;
• making pairs with respect to the bottom values and the peak values adjacent to each other on the time axis to obtain bottom-to-peak amplitude values along the time axis, the bottom-to-peak amplitude values being a difference between the bottom value and the peak value in each of the pairs;
• and
• comparing each set of two bottom-to-peak amplitude values adjacent to each other along the time axis to remove the bottom value and the peak value relating to the smaller bottom-to-peak amplitude value in each set as noise, if a ratio of one of the two bottom-to-peak amplitude values to the other one of the two bottom-to-peak amplitude values is larger than a predetermined value;
• obtaining peak-to-peak intervals or bottom-to-bottom intervals corresponding to electrocardiogram RR-intervals based on the pulse wave data from which noise has been removed;
• and
• a signal bearing media bearing the program.

A pulse wave data analyzing system for extracting vital information out of pulse wave data concerning a living body, the system comprising:

• a pulse wave detector for obtaining pulse wave data in association with a time axis;
• and
• a data analyzer for analyzing and removing noise from the pulse wave data, the data analyzer including:
• an inflection point detector adapted to detect bottom values and peak values along the time axis in a time-series manner out of the pulse wave data,
• an amplitude value detector adapted to identify pairs of bottom values and peak values adjacent to each other on the time axis and calculate bottom-to-peak amplitude values along the time axis, the bottom-to-peak amplitude values being a difference between the bottom value and the peak value in each of the pairs of bottom values and peak values,
• a noise remover adapted to calculate a ratio between each set of bottom-to-peak amplitude values adjacent to each other along the time axis and removing the bottom value and the peak value corresponding to the smaller bottom-to-peak amplitude value of each set as noise, if the ratio is larger than a predetermined value, and
• an interval calculator adapted to obtain peak-to-peak intervals or bottom-to-bottom intervals corresponding to electrocardiogram RR-intervals based on pulse wave data from which noise has been removed by the noise remover.