Apparatus for monitoring cardiovascular regulation using heart rate

Abstract

Apparatus for heart rate fluctuation power spectrum analysis obtains an electrocardiogram signal from an electrocardiograph machine and a respiratory rate signal from an electroplethysmograph machine. These signals are processed by a data acquisition system to provide output suitable for heart rate fluctuation power spectrum analysis by a mini-micro-computer. Data manipulation includes correction of artifacts by substituting an appropriate heartbeat interval for detected heartbeat intervals for which the variance exceeds a preselected range of slewing rates. Trending of data and overlapping data analysis increase the analytical capabilities of the apparatus. Methods of treatment for conditions manifested by abnormalities in a heart rate fluctuation power spectrum involve applying treatments when spectral abnormalities are observed. Specific abnormalities indicating the need for treatment include: a level below about 0.1 (beats/min.).sup.2 in the power spectrum of heart rate fluctuations at a frequency between about 0.04 and about 0.10 Hz; a marked increase to above about 10 (beats/min.).sup.2 in heart rate fluctuations at a frequency between 0.04 and about 0.10 Hz; and a ratio of the area under a heart rate fluctuation power spectrum of a peak at a frequency between about 0.04 and about 0.10 Hz to the area under a peak in the respiratory heart rate fluctuation power spectrum centered at the mean respiratory rate (as measured by the apparatus) at about 0.1 Hz as having a value less than 2.0 for longer than or equal to about one hour or as having an absolute value greater than about 50.