心室复极化时程变异的谱分解技术及其临床应用

当今，心血管疾病发病率日益增加，研究者业已致力于从心曜误事 提取对心脏疾病能早期诊断、监护及预后评估有价值的信息。心室肌发生病变时，心室复极化时程与ＲＲ间期的关系会发生相应变化。且具有明显的特征性。因此有必要建立心室极化时程与ＲＲ间期关系所分析方法，以便对心室复极化时程的生理机抽进一步深入研究，并最终为心血管疾病的诊治提供新的无创性的方法。我们利用系统辨识方法建立了心室复极化时程的ＲＲ间期系统的动态线性参数模型，利用功率谱分解技术把心室复极化时程的功率谱分解成与生理因素有关和与病理因素有关两种成分，定量描述心肌细胞的受损程度。我们开展了这方面的临床研究工作，分别研究正常人各年龄组间以及正常人（老年组）和病人（老年组）间相应指标的变化。对缺血性心脏病人的研究结果表明，在心室复极化时程变异的功率谱中，与病理因素有关的成分显著增大；而且反映心脏病人心肌细胞状态不可测因素（病理因素）的有色随机噪声的能量亦显著增大。心室复极化时程与ＲＲ间期关系的分析方法，具有无创性和可定量性。随着心室复极化时程与ＲＲ间期关系研究的不断深入，将评价心血管疾病和功能的无创性方法日臻完善，必将对临床心血管疾病的早期诊断、治疗和预后评估等发挥积极的作用。

THE SPECTRAL DECOMPOSITIONTECHNIQUE IN VENTRICULAR REPOLARIZATION DURATION VARIABILITY AND ITS CLINIC APPLICATION

Researchers have devoted to obtain valuable information from ECG, which is helpful in early diagnosis, monitoring and prognostic assessment of cardiovascular diseases. When ventricular myocardium is ischemic, the relation between ventricular repolarization duration and RR interval will be changed correspondently and characteristically. It is necessary to develop a set of methods to analyze repolarization duration variability (RDV) and the relation between ventricular repolarization duration and RR interval. It can be used to study the physiological mechanism of repolarization duration and to provide new non-invasive methods for cardiovascular diseases.　　A dynamic linear parametric model was designed to quantitate the relation between ventricular repolarization duration and RR interval by system identification techniques. The RDV spectra was divided into physiology-related and pathology-related parts by the spectral decomposition techniques. It is emphasized that, this method is useful especially in describing the injured myocardial cells quantitatively. We carried out clinical researches using this technique. We studied indexes among different aged groups of normal subjects, as well as those between normal subjects and patients with heart diseases. The results of ischemic cardiovascular patients indicated that the pathology-related part of RDV spectra increased significantly. Immeasurable colored stochastic noise energy reflecting the state of myocardial cells also increased significantly.　　These methods of analysis of relation between ventricular repolarization duration and RR interval are non-invasive and quantitative. With the development of this study, this approach will provide a more useful non-invasive evaluation of cardiovascular diseases and function. It will be more helpful for early diagnosis, monitoring and prognostic assessment of cardiovascular diseases.