Fractal dimension in health and heart failure.
BACKGROUND
Non-linear analysis of heart rate variability (HRV) can give additional information about autonomic control of the heart rate. This study applied the fractal dimension (FD) in a congestive heart failure (CHF) population.


METHODS
FD and HRV were evaluated in a healthy population (n=21) and an end-stage heart failure population (n=21) using 1-h segments during the day and night from Holter recordings.


RESULTS
CHF patients presented a loss of circadian variation in both FD and conventional time- and frequency-domain HRV indices. FD was higher in the CHF population both during the day and night. In the CHF population the correlation between FD and high-frequency power of HRV was lost.


CONCLUSIONS
Day-night variations of heart rate fluctuations are lost in heart failure. Changes in FD reflecting physiological and pathophysiological changes were observed.
Beckers
Frank
F
Laboratory of Experimental Cardiology, Department of Cardiovascular Diseases, University Hospital Gasthuisberg, Leuven, Belgium. frank.beckers@med.kuleuven.be
Verheyden
Bart
B
Couckuyt
Kurt
K
Aubert
André E
AE
D000465:Algorithms; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D001683:Biological Clocks; D002940:Circadian Rhythm; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D017709:Fractals; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009991:Oscillometry / Q000379:methods