title: Non-Linear Heart Rate Variability Indices in the Frequent Hemodialysis Network Trials of Chronic Hemodialysis Patients.
abstract: BACKGROUND
  Non-linear heart rate variability (HRV) indices were hypothesized to correlate with cardiac function, fluid overload and physical performance in hemodialysis patients.
  
  
  METHODS
  Twenty-four-hour Holter electrocardiograms were recorded in patients enrolled in the Frequent Hemodialysis Network (FHN) Daily Dialysis Trial. Correlations between non-linear HRV indices and left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), extracellular volume (ECV)/total body water (TBW) ratio, the SF-36 Physical Health Composite (PHC) and Physical Functioning (PF) scores were tested.
  
  
  RESULTS
  We studied 210 subjects (average age 49.8 ± 13.5 years, 62% men, 42% diabetics). In non-diabetic patients, multiscale entropy (MSE) slope sample entropy (SampEn) and approximate entropy (ApEn) correlated positively with LVEF, PF and PHC and inversely with LVEDV and ECV/TBW. Spectral power slope correlated positively with ECV/TBW (r = 0.27). Irregularity measures (MSE ApEn and MSE SampEn) correlated positively with LVEDV (r = 0.19 and 0.20).
  
  
  CONCLUSIONS
  Non-linear HRV indices indicated an association between a deteriorated heart rate regulatory system and impaired cardiac function, fluid accumulation and poor physical condition.
authors.affiliation: Politecnico di Milano, Department of Electronics, Information and Bioengineering (DEIB), Milano, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Ferrario
authors.forename: Jochen G
authors.initials: JG
authors.lastname: Raimann
authors.forename: Brett
authors.initials: B
authors.lastname: Larive
authors.forename: Andreas
authors.initials: A
authors.lastname: Pierratos
authors.forename: Stephan
authors.initials: S
authors.lastname: Thijssen
authors.forename: Sanjay
authors.initials: S
authors.lastname: Rajagopalan
authors.forename: Tom
authors.initials: T
authors.lastname: Greene
authors.forename: Sergio
authors.initials: S
authors.lastname: Cerutti
authors.forename: Gerald
authors.initials: G
authors.lastname: Beck
authors.forename: Christopher
authors.initials: C
authors.lastname: Chan
authors.forename: Peter
authors.initials: P
authors.lastname: Kotanko
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D015716:Electrocardiography, Ambulatory; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D006435:Renal Dialysis / Q000009:adverse effects / Q000379:methods; D013318:Stroke Volume; D016277:Ventricular Function, Left