A method for trend subtraction and its effect on long-term monitoring of the low-frequency range of the heart rate variation is described. Slow trend removal is used prior to applying an autoregressive power spectral analysis to Holter heart rate data. Careful application of this trend removal algorithm reveals important changes in slow periodic heart rate fluctuations that are related to the activity of the automatic nervous system. These changes are otherwise masked by nonperiodic alterations
Date of Conference: 9-12 Nov 1989