title: Scale-independent measures and pathologic cardiac dynamics.
abstract: We study several scale-independent measures of cardiac interbeat interval dynamics defined through the application of the wavelet transform. We test their performance in detecting heart disease using a database consisting of records of interbeat intervals for a group of healthy individuals and subjects with congestive heart failure. We find that scale-independent measures effectively distinguish healthy from pathologic behavior and propose a new two-variable scale-independent measure that could be clinically useful. We compare the performance of a recently proposed scale-dependent measure and find that the results depend on the database analyzed and on the analyzing wavelet.
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge 02139, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Nunes Amaral
authors.forename: A L
authors.initials: AL
authors.lastname: Goldberger
authors.lastname: Ivanov PCh
authors.forename: H E
authors.initials: HE
authors.lastname: Stanley
mesh_terms: D003627:Data Interpretation, Statistical; D006321:Heart / Q000502:physiology / Q000503:physiopathology*; D006333:Heart Failure / Q000175:diagnosis* / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008433:Mathematics; D008955:Models, Cardiovascular; D012815:Signal Processing, Computer-Assisted