title: Development of more erratic heart rate patterns is associated with mortality post-myocardial infarction.
abstract: Cardiac patients often have sinus arrhythmia of nonrespiratory origin (erratic sinus rhythm [ESR]). ESR was quantified using hourly Poincaré and power spectral heart rate variability plots from normal-to-normal interbeat intervals and hourly values of the short-term fractal scaling exponent and correlations of normal-to-normal intervals in n = 60 nonsurvivors and n = 66 randomly selected survivors in the Cardiac Arrhythmia Suppression Trial. Hours were coded (ABN) as normal (0), borderline (0.5), or ESR (1). t Tests compared ABN for n = 2413 paired hours at baseline and on therapy. ABN was higher in nonsurvivors (0.38 +/- 0.44 vs 0.28 +/- 0.40, baseline, and 0.51 +/- 0.45 vs 0.34 +/- 0.43, on therapy, P < .001). Increased ABN with treatment were greater in nonsurvivors. Normal hours at baseline (relative risk = 0.77; 095% confidence interval, 0.62-0.96, P = .018) and on treatment (relative risk = 0.47; 95% confidence interval, 0.39-0.58) were significantly associated with decreased mortality compared with ESR. Quantification of ESR may identify more vulnerable patients or help monitor the effects of pharmacologic treatment.
authors.affiliation: Washington University School of Medicine, Heart Rate Variability Laboratory, St Louis, MO 63121, USA. pstein@im.wustl.edu
authors.forename: Phyllis K
authors.initials: PK
authors.lastname: Stein
authors.forename: QuyChi
authors.initials: Q
authors.lastname: Le
authors.forename: Peter P
authors.initials: PP
authors.lastname: Domitrovich
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality*; D015897:Comorbidity; D015716:Electrocardiography, Ambulatory / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008923:Missouri / Q000453:epidemiology; D009203:Myocardial Infarction / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control*; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate
chemical_list: D000889:Anti-Arrhythmia Agents