Correlation dimension analysis of heart rate variability in patients with dilated cardiomyopathy.
A correlation dimension analysis of heart rate variability (HRV) was applied to a group of 55 patients with dilated cardiomyopathy (DCM) and 55 healthy subjects as controls. The 24-h RR time series for each subject was divided into segments of 10,000 beats to determine the correlation dimension (CD) per segment. A study of the influence of the time delay (lag) in the calculation of CD was performed. Good discrimination between both groups (p<0.005) was obtained with lag values of 5 or greater. CD values of DCM patients (8.4+/-1.9) were significantly lower than CD values for controls (9.5+/-1.9). An analysis of CD values of HRV showed that for healthy people, CD night values (10.6+/-1.8) were significant greater than CD day values (9.2+/-1.9), revealing a circadian rhythm. In DCM patients, this circadian rhythm was lost and there were no differences between CD values in day (8.8+/-2.4) and night (8.9+/-2.1).
Carvajal
Raúl
R
Faculty of Computer Science, University of Sinaloa, 82017 Mazatlan, Mexico.
Wessel
Niels
N
Vallverdú
Montserrat
M
Caminal
Pere
P
Voss
Andreas
A
D000328:Adult; D000465:Algorithms; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology; D016022:Case-Control Studies; D002940:Circadian Rhythm; D005260:Female; D005858:Germany; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D013223:Statistics as Topic / Q000379:methods*