Baumert Mathias, Baier Vico, Truebner Sandra, Schirdewan Alexander, Voss Andreas
Department of Medical Engineering, University of Applied Sciences Jena, 07745 Jena, Germany.
IEEE Trans Biomed Eng. 2005 Dec;52(12):2112-5. doi: 10.1109/TBME.2005.857636.
Autonomic cardiovascular control involves complex interactions of heart rate and blood pressure. In patients with dilated cardiomyopathy (DCM), this control is impaired and parameters for its quantification might be of prognostic importance. In this paper, we introduce methods based on joint symbolic dynamics (JSD) for the enhanced analysis of heart rate and blood pressure interactions. To assess the coarse-grained dynamics beat-to-beat changes of heart rate and blood pressure are encoded in symbol strings. Subsequently, the distribution properties of short symbol sequences (words) as well as the scaling properties of the whole symbol string are assessed. The comparison of joint symbolic heart rate and blood pressure dynamics in DCM (n = 75) with those in healthy controls (n = 75) showed significant changes. Both, the distribution of words and the scaling properties indicate a loss in heart rate dynamics associated with blood pressure regulation in DCM. In conclusion, the analyses of short- and long-term JSDs provide insights into complex physiological heart rate and blood pressure interactions and furthermore reveal patho-physiological cardiovascular control in DCM.
自主心血管控制涉及心率和血压的复杂相互作用。在扩张型心肌病（DCM）患者中，这种控制受到损害，其量化参数可能具有预后重要性。在本文中，我们介绍了基于联合符号动力学（JSD）的方法，用于增强对心率和血压相互作用的分析。为了评估粗粒化动力学，逐搏的心率和血压变化被编码在符号串中。随后，评估短符号序列（词）的分布特性以及整个符号串的标度特性。对DCM患者（n = 75）和健康对照者（n = 75）的联合符号心率和血压动力学进行比较，结果显示有显著变化。词的分布和标度特性均表明，DCM患者在与血压调节相关的心率动力学方面存在缺失。总之，对短期和长期JSD的分析有助于深入了解复杂的生理心率和血压相互作用，并且进一步揭示DCM患者的病理生理心血管控制情况。
