title: Multiscale entropy analysis of heart rate variability in heart failure, hypertensive, and sinoaortic-denervated rats: classical and refined approaches.
abstract: The analysis of heart rate variability (HRV) by nonlinear methods has been gaining increasing interest due to their ability to quantify the complexity of cardiovascular regulation. In this study, multiscale entropy (MSE) and refined MSE (RMSE) were applied to track the complexity of HRV as a function of time scale in three pathological conscious animal models: rats with heart failure (HF), spontaneously hypertensive rats (SHR), and rats with sinoaortic denervation (SAD). Results showed that HF did not change HRV complexity, although there was a tendency to decrease the entropy in HF animals. On the other hand, SHR group was characterized by reduced complexity at long time scales, whereas SAD animals exhibited a smaller short- and long-term irregularity. We propose that short time scales (1 to 4), accounting for fast oscillations, are more related to vagal and respiratory control, whereas long time scales (5 to 20), accounting for slow oscillations, are more related to sympathetic control. The increased sympathetic modulation is probably the main reason for the lower entropy observed at high scales for both SHR and SAD groups, acting as a negative factor for the cardiovascular complexity. This study highlights the contribution of the multiscale complexity analysis of HRV for understanding the physiological mechanisms involved in cardiovascular regulation.
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil;
authors.forename: Luiz Eduardo Virgilio
authors.initials: LE
authors.lastname: Silva
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil;
authors.forename: Renata Maria
authors.initials: RM
authors.lastname: Lataro
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil;
authors.forename: Jaci Airton
authors.initials: JA
authors.lastname: Castania
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil;
authors.forename: Carlos Alberto Aguiar
authors.initials: CA
authors.lastname: da Silva
authors.affiliation: Department of Electronic Engineering, University San Buenaventura, Cali, Colombia;
authors.forename: Jose Fernando
authors.initials: JF
authors.lastname: Valencia
authors.affiliation: Department of Computing and Mathematics, School of Philosophy, Sciences and Letters, University of São Paulo, Ribeirão Preto, São Paulo, Brazil;
authors.forename: Luiz Otavio
authors.initials: LO
authors.lastname: Murta
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil;
authors.forename: Helio Cesar
authors.initials: HC
authors.lastname: Salgado
authors.affiliation: Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil; rfazan@usp.br.
authors.forename: Rubens
authors.initials: R
authors.lastname: Fazan
authors.affiliation: Department of Biomedical Sciences for Health, University of Milan, Milan, Italy; and Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, Milan, Italy.
authors.forename: Alberto
authors.identifier: 0000-0002-6720-9824
authors.initials: A
authors.lastname: Porta
mesh_terms: D000818:Animals; D001341:Autonomic Nervous System / Q000502:physiology; D003714:Denervation; D019277:Entropy; D006333:Heart Failure / Q000503:physiopathology*; D006339:Heart Rate; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D017208:Rats, Wistar; D015656:Respiratory Mechanics; D012850:Sinus of Valsalva; D014630:Vagus Nerve
keywords: autonomic nervous system; baroreflex; cardiovascular control; complexity; heart failure; heart rate variability; hypertension; refined multiscale entropy