{"title":"Multifractal analysis of the day and night characteristics of heart rate variability","authors":"S. Ramchurn, A. Murray","doi":"10.1109/CIC.2002.1166799","DOIUrl":null,"url":null,"abstract":"The RR heart rate variability characteristics of normal subjects were studied to compare the multifractal characteristics during day and night. The RR intervals were obtained from 24-hour digital Holter ECG recordings of normal subjects, starting at midday. Each 24 hour period was split into 4 blocks of 6-hour which were analysed separately. The overnight period was fully contained in the third block, between midnight to 6 a.m. The 6-hour blocks were analysed using a wavelet transform multifractal formalism. Each spectrum peaked between the Hurst exponent (h) limits of 0.07 and 0.29. In one subject the overnight spectrum did not have a consistent overnight peak and could not be analysed. In the subjects with well-defined spectral peaks, the overnight peak position of h tended to be greater than that for any of the other three 6-hour periods, indicating that the fractal characteristics of the RR intervals differ during the overnight sleep period.","PeriodicalId":80984,"journal":{"name":"Computers in cardiology","volume":"1 1","pages":"421-424"},"PeriodicalIF":0.0000,"publicationDate":"2002-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/CIC.2002.1166799","citationCount":"6","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Computers in cardiology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/CIC.2002.1166799","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 6
Abstract
The RR heart rate variability characteristics of normal subjects were studied to compare the multifractal characteristics during day and night. The RR intervals were obtained from 24-hour digital Holter ECG recordings of normal subjects, starting at midday. Each 24 hour period was split into 4 blocks of 6-hour which were analysed separately. The overnight period was fully contained in the third block, between midnight to 6 a.m. The 6-hour blocks were analysed using a wavelet transform multifractal formalism. Each spectrum peaked between the Hurst exponent (h) limits of 0.07 and 0.29. In one subject the overnight spectrum did not have a consistent overnight peak and could not be analysed. In the subjects with well-defined spectral peaks, the overnight peak position of h tended to be greater than that for any of the other three 6-hour periods, indicating that the fractal characteristics of the RR intervals differ during the overnight sleep period.