title: Clinical significance of heart rate turbulence assessment in patients with chronic heart failure.
abstract: BACKGROUND
  Heart rate turbulence (HRT) is modulated by the baroreceptor reflex, and it has been suggested that it could be used as a measure of autonomic dysfunction. Impaired HRT has a significant prognostic value in patients after myocardial infarction. The usefulness of HRT parameters in CHF patients has not yet been well established.
  
  
  OBJECTIVE
  To assess the relationship between HRT parameters, clinical course of CHF and selected biochemical markers with respect to their prognostic value in CHF patients.
  
  
  METHODS
  A 64 of 100 consecutive CHF patients, in whom it was possible to calculate HRT, were divided into four groups according to NYHA class. Uric acid (UA) and brain natriuretic peptide (BNP) concentrations were measured. Heart rate turbulence was analysed from 24-hour Holter ECG and characterised by two parameters: turbulence onset (TO) and turbulence slope (TS). The results of 20 healthy persons served as a control group. Follow-up examinations were performed after 6 and 12 months.
  
  
  RESULTS
  In patients with CHF both HRT parameters (TO and TS) were significantly impaired in comparison to TO and TS in healthy subjects. A negative correlation between these parameters was found. A strong positive correlation between TO and NYHA class and a significant negative correlation between TS and BNP and UA concentrations were observed. There were 11 deaths during one-year follow-up. Patients who died due to CHF had significantly lower TS and higher TO values in comparison to survivors.
  
  
  CONCLUSIONS
  Heart rate turbulence is impaired in CHF patients. HRT parameters show a significant correlation with some clinical factors: NYHA class, BNP and UA concentrations. Both HRT parameters, TO and TS, seem to be significant prognostic markers in patients with CHF.
authors.affiliation: 2nd Department of Cardiology, Medical University, Poznan, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szymanowska
authors.forename: Anna
authors.initials: A
authors.lastname: Piatkowska
authors.forename: Anna
authors.initials: A
authors.lastname: Nowicka
authors.forename: Marek
authors.initials: M
authors.lastname: Michalski
authors.forename: Rafał
authors.initials: R
authors.lastname: Dankowski
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kandziora
authors.forename: Wojciech
authors.initials: W
authors.lastname: Biegalski
authors.forename: Michał
authors.initials: M
authors.lastname: Wierzchowiecki
authors.forename: Kajetan
authors.initials: K
authors.lastname: Poprawski
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000453:epidemiology* / Q000503:physiopathology; D016022:Case-Control Studies; D015984:Causality; D002908:Chronic Disease; D015897:Comorbidity; D015716:Electrocardiography, Ambulatory; D005260:Female; D006333:Heart Failure / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D011311:Pressoreceptors / Q000503:physiopathology; D011379:Prognosis; D016019:Survival Analysis; D014527:Uric Acid / Q000097:blood
chemical_list: D020097:Natriuretic Peptide, Brain; D014527:Uric Acid