METHOD FOR DETERMINING A FUNCTIONAL CONDITION OF A PERSON BY A PHONOCARDIOGRAM Russian patent published in 2019 - IPC A61B5/02 

FIELD: medicine.

SUBSTANCE: invention relates to medicine. Method for determining a functional state (FS) of a person by a phonocardiogram (PCG) involves forming a dynamic series of cardiointervals, calculation of voltage index (VI) of regulatory systems, determination of FS depending on value of VI. PCG is recorded on the apex of the heart, the I tone is recognized on the initial PHG fragment with duration of 2–3 s by way of threshold signal filtration with subsequent measurement of pauses duration between three consecutive amplitudes. Number of count, which is preceded by the maximum pause, is recorded as the start of the first tone and the count corresponding to its end is determined. Scanning interval corresponding to I tone duration, and the reading with the maximum amplitude is recorded as the first (initial) reading of the I tone on the PCG, and subsequent readings of the I tones by the maximum amplitude at the intervals [n1 n2] are determined. Duration of cardio intervals is calculated between I tones of PCG and intra-cycle parameters of cardiac activity are additionally determined: systole, diastole and ratio of amplitudes of I and II tones. Counts of the II tones are determined from the maximum amplitude on the intervals [n3 n4]. Systole values are determined by the number of readings between the I and II tone, the diastole by subtracting the systole from the duration of the cardio interval and the values of the dynamic rows of intra-cycle parameters (systole and diastole) by variational pulsometry. It is compared with standard values and, in cases of exceeding them in premorbid state, observing the presence of a pathological process.

EFFECT: higher sensitivity of PS assessment and early detection of the beginning of the pathological process by determining phases of the cardiac cycle and ratios of I and II tones.

1 cl, 3 dwg