Abstract
In the context of HRV analysis, we evaluated the information content of two measures that can easily be derived from the classical RR time-domain indexes. The two measures are: 1) the ratio sd/rmssd, where sd is the RR standard deviation and rmssd is the root mean square of squared differences of consecutive RR beats; and 2) the ratio sd2/sd1, where sd2 and sd1 are extracted from the Poincaré plot and represent the transversal and longitudinal dispersion of the cloud of points (RRi,RRi+1). We compared the performance of the two measures with that of the classical LF/HF ratio in a group of healthy subjects who underwent a 70° upright tilt test. The goodness of the results obtained by the two measures, the simplicity of their calculation and their applicability free from a priori assumptions on the characteristics of the data are proposed to the attention of the community involved in the HRV analysis as a possible alternative to the LF/HF ratio.
References
1 Nolan J, Batin PD, Andrews R, et al. Prospective study of heart rate variability and mortality in chronic heart failure: results of the United Kingdom heart failure evaluation and assessment of risk trial (UK-HEART). Circulation1998; 98: 1510–1516.10.1161/01.CIR.98.15.1510Search in Google Scholar
2 Lanza GA, Pedrotti P, Rebuzzi AG, Pasceri V, Quaranta G, Maseri A. Usefulness of the addition of heart rate variability to Holter monitoring in predicting in-hospital cardiac events in patients with unstable angina pectoris. Am J Cardiol1997; 80: 263–267.10.1016/S0002-9149(97)00343-3Search in Google Scholar
3 Kleiger RE, Miller JP, Bigger JT Jr, Moss AJ. Decreased heart rate variability and its association with increased mortality after acute myocardial infarction. Am J Cardiol1987; 59: 256–262.10.1016/0002-9149(87)90795-8Search in Google Scholar
4 Malliani A. The pattern of sympathovagal balance explored in the frequency domain. News Physiol Sci1999; 14: 111–117.10.1152/physiologyonline.1999.14.3.111Search in Google Scholar
5 Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Heart rate variability: standards of measurement, physiological interpretation and clinical use. Circulation 1996; 93: 1043–1065.Search in Google Scholar
6 Sandercock GRH, Bromley PD, Brodie DA. The reliability of short-term measurements of heart rate variability. Int J Cardiol2005; 103: 238–247.10.1016/j.ijcard.2004.09.013Search in Google Scholar
7 Bergfeldt L, Haga Y. Power spectral and Poincaré plot characteristics in sinus node dysfunction. J Appl Physiol2003; 94: 2217–2224.10.1152/japplphysiol.01037.2002Search in Google Scholar
8 Mourot L, Bouhaddi M, Perrey S, Rouillon JD, Regnard J. Quantitative Poincaré plot analysis of heart rate variability: effect of endurance training. Eur J Appl Physiol2004; 91: 79–87.10.1007/s00421-003-0917-0Search in Google Scholar
9 Mourot L, Bouhaddi M, Perrey S, et al. Decrease in heart rate variability with overtraining assessment by the Poincaré plot analysis. Clin Physiol Funct Imaging2004; 24: 10–18.10.1046/j.1475-0961.2003.00523.xSearch in Google Scholar
10 Korhonen I, Mainardi LT, Yppärilä H, Musialowicz T. Comparison of linear and non-linear analysis of heart rate variability in sedated cardiac surgery patients. In: Proceedings of the 23rd Annual International IEEE Conference of the Engineering in Medicine and Biology Society, Istanbul, Turkey, October 25–28, 2001. Piscataway: IEEE Press 2000: 496–499.Search in Google Scholar
11 Brennan M, Palaniswami M, Kamen P. Do existing measures of Poincaré plot geometry reflect nonlinear features of heart rate variability? IEEE Trans Biomed Eng2001; 48: 1342–1347.10.1109/10.959330Search in Google Scholar
12 Toichi M, Sugiura T, Murai T, Sengoku A. A new method of assessing cardiac autonomic function and its comparison with spectral analysis and coefficient of variation of R-R interval. J Auton Nerv Syst1997; 62: 79–84.10.1016/S0165-1838(96)00112-9Search in Google Scholar
13 Toichi M, Kubota Y, Murai T, et al. The influence of psychotic states on the autonomic nervous system in schizophrenia. Int J Psychophysiol1999; 31: 147–154.10.1016/S0167-8760(98)00047-6Search in Google Scholar
14 Kubota Y, Sato W, Toichi M, et al. Frontal midline theta rhythm is correlated with cardiac autonomic activities during the performance of an attention demanding meditation procedure. Cogn Brain Res2001; 11: 281–287.10.1016/S0926-6410(00)00086-0Search in Google Scholar
15 Toichi M, Kamio Y. Paradoxical autonomic response to mental task in autism. J Autism Dev Disord2003; 33: 417–426.10.1023/A:1025062812374Search in Google Scholar
16 Brennan M, Palaniswami M, Kamen P. Poincaré plot interpretation using a physiological model of HRV based on a network of oscillators. Am J Physiol Heart Circ Physiol2002; 283: 1873–1886.10.1152/ajpheart.00405.2000Search in Google Scholar PubMed
©2006 by Walter de Gruyter Berlin New York
