PMID- 15820283
OWN - NLM
STAT- MEDLINE
DCOM- 20050831
LR  - 20090626
IS  - 0167-5273 (Print)
IS  - 0167-5273 (Linking)
VI  - 100
IP  - 1
DP  - 2005 Apr 8
TI  - Characteristics of heart beat intervals and prediction of death.
PG  - 37-45
AB  - OBJECTIVE: To assess the value for improving risk stratification of measures, 
      unadjusted and adjusted for heart rate, of heart rate variability (HRV) and heart 
      rate turbulence (HRT) based on 2- to 24-h ambulatory electrocardiographic 
      recordings; and to relate this to the decision to use an implantable cardiac 
      defibrillator (ICD) and the attendant consequences on effectiveness and 
      cost-effectiveness. BACKGROUND: Risk stratification for high risk or low risk of 
      lethal ventricular arrhythmic events, and hence for a decision about 
      defibrillator implant, most commonly utilizes the left ventricular ejection 
      fraction (LVEF). Electrocardiographic (ECG) approaches include 24-h ambulatory 
      ECG recordings, with counts of ventricular premature contractions (VPCs), 
      measures of heart rate variability (HRV), and heart rate turbulence (HRT). HRT 
      has two components: turbulence onset (TO) and turbulence slope (TS). METHODS AND 
      RESULTS: We evaluated the qualifying ambulatory ECG recordings from 744 patients 
      in the active treatment arms of the Cardiac Arrhythmia Suppression Trial (CAST). 
      Beat characteristics, VPC counts, normal-to-normal beat intervals, and 
      time-domain measures of HRV and HRT were calculated. Tachograms were rescaled to 
      a heart rate of 75 and the resulting "normalized" measures evaluated as risk 
      predictors for death, compared to unnormalized measures. Measures based on 2-h 
      ECGs were also evaluated as risk predictors. The most powerful univariate 
      predictor of survival was the normalized turbulence slope. The best multivariate 
      prediction model had six components: history of angina, hypertension, diabetes, 
      and absence of post-myocardial infarction revascularization, the log of LVEF, 
      normalized TS, HR, and an interaction term of HR and normalized TS. Gains in 
      effectiveness from use of this model cost between $0 and $4000 per year of life 
      saved. CONCLUSIONS: Turbulence slope substantially exceeded other ECG-based 
      measures in improving prediction of subsequent death in models which included 
      LVEF, and other clinical parameters. Use of this model would improve the 
      effectiveness and cost-effectiveness of the ICD.
FAU - Hallstrom, Alfred P
AU  - Hallstrom AP
AD  - Department of Biostatistics, University of Washington, Clinical Trial Center, 
      1107 N.E. 45th Street, Suite 505, Seattle, WA 98105-4689, United States. 
      aph@u.washington.edu
FAU - Stein, Phyllis K
AU  - Stein PK
FAU - Schneider, Raphael
AU  - Schneider R
FAU - Hodges, Morrison
AU  - Hodges M
FAU - Schmidt, Georg
AU  - Schmidt G
FAU - Ulm, Kurt
AU  - Ulm K
CN  - CAST Investigators
LA  - eng
GR  - R0-3 HL 53776/HL/NHLBI NIH HHS/United States
GR  - R0-3 HL53776/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - Int J Cardiol
JT  - International journal of cardiology
JID - 8200291
SB  - IM
MH  - Arrhythmias, Cardiac/*mortality/*physiopathology
MH  - Cost-Benefit Analysis
MH  - Decision Support Techniques
MH  - Defibrillators, Implantable
MH  - Electrocardiography, Ambulatory
MH  - *Heart Rate
MH  - Humans
MH  - Risk Assessment
MH  - Survival Analysis
EDAT- 2005/04/12 09:00
MHDA- 2005/09/01 09:00
CRDT- 2005/04/12 09:00
PHST- 2000/01/13 00:00 [received]
PHST- 2004/04/07 00:00 [revised]
PHST- 2004/05/05 00:00 [accepted]
PHST- 2005/04/12 09:00 [pubmed]
PHST- 2005/09/01 09:00 [medline]
PHST- 2005/04/12 09:00 [entrez]
AID - S0167-5273(04)00542-X [pii]
AID - 10.1016/j.ijcard.2004.05.047 [doi]
PST - ppublish
SO  - Int J Cardiol. 2005 Apr 8;100(1):37-45. doi: 10.1016/j.ijcard.2004.05.047.