



@conference {2388,
	title = {Characterization of fetal heart rate irregularity using approximate entropy and wavelet filtering},
	booktitle = {Computers in CardiologyComput Cardiol},
	series = {2006 Computers in Cardiology, CIC},
	volume = {33},
	year = {2006},
	note = {Conference code: 73228Cited By (since 1996): 3Export Date: 21 November 2012Source: ScopusArt. No.: 4512006CODEN: COCADLanguage of Original Document: EnglishCorrespondence Address: Marques De S{\'a}, J. P.; Faculdade de Engenharia, DEEC, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; email: jmsa@fe.up.ptReferences: Pincus, S., Approximate entropy as a measure of system complexity (1991) Proc. Natl. Acad. Sci. U.S.A, 88, pp. 2297-2301;Pincus, S., Randomness and degrees of irregularity (1996) Proc. Natl. Acad. Sci. U.S.A, 93, pp. 2083-2088; 
Pincus, S.M., Viscarello, R.R., Approximate entropy: A regularity measure for fetal heart rate (1992) Obstet. Gynecol, 2, pp. 249-255; 
Fleisher, L.A., Dipietro, J.A., Johnson, T.R., Pincus, S., Complementary and non-coincident increases in heart rate variability and irregularity during fetal development (1997) Clin. Sci, 4, pp. 345-349; 
van Leeuwen, P., Lange, S., Betterman, H., Gronemeyer, D., Hatzmann, W., Fetal heart rate variability and complexity in the course of pregnancy (1999) Early Human Develop, 54, pp. 259-269; 
Pincus, S., Assessing Serial Irregularity and its Implications for Health (2001) Ann N Y Acad Sci, 954, pp. 245-267; 
Cysarz, D., Betterman, H., van Leeuwen, P., Entropies of short binary sequences in heart period dynamics (2000) Am J Physiol Heart Circ Physiol, 6, pp. 2163-2172; 
Signorini, M.G., Magenes, G., Cerutti, S., Arduini, D., Linear and Nonlinear Parameters for the Analysis of Fetal Heart Rate Signal from Cardiotocographic Recordings (2003) IEEE Tr. BME, 50, pp. 365-373; 
Ayres-de-Campos, D., Bernardes, J., Garrido, A., Marques-de-S{\'a}, J., Pereira-Leite, L., SisPorto 2.0 - A Program for Automated Analysis of Cardiotocograms (2000) J Matern Fetal Med, 9, pp. 311-318; 
S{\'a} Couto, P.M., van Meurs, W.L., Bernardes, J.F., Marques de, S.J., Goodwin, J.A., Combined Model-Driven and Rule-Based Approach for Educational Simulation of Fetal Heart Rate (2002) Proc. 16th Biennial Int. Conf. Europ. Assoc. for Speech, Signal and Image Processing, pp. 400-402. , EURASIP, Brno, Czech Rep, pp; 
Marques de S{\'a}, J.P., Characterization of fetal heart rate using approximate entropy (2005) Proc. IEEE Comp. in Cardiology 2005, 32, pp. 671-673
},
	month = {2006///},
	pages = {933 - 936},
	address = {Valencia},
	abstract = {Approximate Entropy (ApEn) has been used by several researchers as a means to characterize the irregularity of fetal heart rate (FHR), a major contributor to fetal risk assessment. The present work starts by analyzing the influence of accelerative and decelerative (AD) components of the FHR signal in the computation of ApEn. Having shown that the AD components may completely distort the ApEn evaluation we proceed to present two methods of eliminating the influence of the AD components: wavelet filtering; AD detection using specific algorithms based on well-established physiological criteria. We obtained good results with the first method when applied to simulated signals; however it proved unreliable in the practical application of discriminating normal from pathological fetal FHR. With the second method we were able to achieve this discrimination with high statistical significance.},
	keywords = {Approximate entropy, Cardiology, Fetal heart rate, Neonatal monitoring, Occupational risks, Physiological models, risk assessment, Risk management, Safety engineering, Simulated signals, Statistical significance, Wavelet filtering},
	isbn = {02766574 (ISSN); 1424425328 (ISBN); 9781424425327 (ISBN)},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-50149100681\&partnerID=40\&md5=51e2dd8109d66e30498d7c2f8689c820},
	author = {Magalh{\~a}es, F. and Marques De S{\'a}, J.P. and Bernardes, J. and Ayres-de-Campos, D.}
}
