Changes in short-term measures of heart rate variability after eight weeks of cardiac rehabilitation

BackgroundIn coronary artery disease (CAD) and following myocardial infarction (MI), activity of the autonomic nervous system is altered. Reduced heart rate variability (HRV) is a risk factor for future cardiac event. Studies reporting changes in HRV post-cardiac rehabilitation (CR) are heterogeneous, due possibly to varied data collection and analysis protocols.AimTo evaluate changes in spectral measures of HRV derived from 5-minute ECG recordings in patients completing an 8 weeks CR programme.MethodsThirty-eight patients (21 males, 17 females, aged 65.6 ± 11.6 years) underwent 5 minutes, supine ECG recordings and standard physiological and psychological assessment pre- and post-CR. A further 23 patients (14 males, 9 females aged 64.9 ± 9 years) acted as controls. Outcome measures were: low frequency power, (LF, 0.04–0.15 Hz) high frequency power (HF, 0.15–0.40 Hz), LF:HF ratio and mean RR interval. Change was assessed by ANCOVA and paired t-tests.ResultsWhen compared with the CT group, the CR group showed significant increases in: SDNN (Δ +6 ms, CR vs. 0 ms CT), HFln (Δ 0.4 log units CR vs. 0 log units CT), LFln (Δ +0.6 log units CR, vs. +0.1 log units CT) and RR interval (Δ +30 ms, CR vs. −28 ms CT).ConclusionsThis is the first study to show significant increases in raw LF and HF power derived from short-term ECG recordings in CR patients. These measures are risk factors for future cardiac event. As CR is associated with increases in these measures it may be viewed as an effective therapy capable of bringing about favourable alterations in autonomic control.

[1]  J. Fleiss,et al.  The ability of several short-term measures of RR variability to predict mortality after myocardial infarction. , 1993, Circulation.

[2]  A. Maseri,et al.  Additional predictive value of heart rate variability in high-risk patients surviving an acute myocardial infarction. , 1999, Cardiologia.

[3]  B. Wennerblom,et al.  Intensive home-based exercise training in cardiac rehabilitation increases exercise capacity and heart rate variability. , 2001, International journal of cardiology.

[4]  M Malik,et al.  Short- and long-term assessment of heart rate variability for risk stratification after acute myocardial infarction. , 1996, The American journal of cardiology.

[5]  Alexandru Dan Corlan,et al.  Prognostic value of heart rate variability after acute myocardial infarction. , 2004, Medical science monitor : international medical journal of experimental and clinical research.

[6]  G. Malfatto,et al.  Effects of cardiac rehabilitation and beta-blocker therapy on heart rate variability after first acute myocardial infarction. , 1998, The American journal of cardiology.

[7]  J. Fleiss,et al.  Time course of recovery of heart period variability after myocardial infarction. , 1991, Journal of the American College of Cardiology.

[8]  F Lombardi,et al.  Autonomic nervous system adaptations to short-term exercise training. , 1992, Chest.

[9]  H. Schumacher,et al.  MITOCHONDRIA IN ONCOGENESIS REVISITED , 1973 .

[10]  M. Malik,et al.  Step wise Strategy of Using Short‐ and Long‐Term Heart Rate Variability for Risk Stratification After Myocardial Infarction , 1996 .

[11]  J. Ickovics,et al.  Effects of propranolol on recovery of heart rate variability following acute myocardial infarction and relation to outcome in the Beta-Blocker Heart Attack Trial. , 2003, The American journal of cardiology.

[12]  T. Church,et al.  Eight weeks of moderate-intensity exercise training increases heart rate variability in sedentary postmenopausal women. , 2004, American heart journal.

[13]  L. Lindblad,et al.  Heart rate variability as a means of assessing prognosis after acute myocardial infarction. A 3-year follow-up study. , 1997, European heart journal.

[14]  A. Camm,et al.  Stepwise strategy of using short- and long-term heart rate variability for risk stratification after myocardial infarction. , 1996, Pacing and clinical electrophysiology : PACE.

[15]  P. Boulay,et al.  Health-care consumption and recurrent myocardial infarction after 1 year of conventional treatment versus short- and long-term cardiac rehabilitation. , 2004, Preventive medicine.

[16]  D. Sapoznikov,et al.  Determinants of Short-Period Heart Rate Variability in the General Population , 2001, Cardiology.

[17]  G. Breithardt,et al.  Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. , 1996 .

[18]  G. Dziekan,et al.  Effect of exercise training on heart rate variability in patients with new-onset left ventricular dysfunction after myocardial infarction. , 2000, American heart journal.

[19]  M. Emdin,et al.  Personality traits and heart rate variability predict long-term cardiac mortality after myocardial infarction. , 2005, European heart journal.

[20]  C. T. Peter,et al.  Exercise conditioning and heart rate variability: Evidence of a threshold effect , 2000, Clinical cardiology.

[21]  F. Iellamo,et al.  Effects of a Residential Exercise Training on Baroreflex Sensitivity and Heart Rate Variability in Patients With Coronary Artery Disease: A Randomized, Controlled Study , 2000, Circulation.

[22]  Alberto Porta,et al.  Effects of cardiac rehabilitation and exercise training on autonomic regulation in patients with coronary artery disease. , 2002, American heart journal.

[23]  M. Everitt,et al.  VIGOROUS EXERCISE IN LEISURE-TIME: PROTECTION AGAINST CORONARY HEART DISEASE , 1980, The Lancet.

[24]  G. Malfatto,et al.  Different baseline sympathovagal balance and cardiac autonomic responsiveness in ischemic and non‐ischemic congestive heart failure , 2001, European journal of heart failure.

[25]  L. Adams,et al.  The shuttle walking test: a reproducible method for evaluating the impact of shortness of breath on functional capacity in patients with advanced cancer , 2001, Thorax.

[26]  G. Billman,et al.  Aerobic exercise conditioning: a nonpharmacological antiarrhythmic intervention. , 2002, Journal of applied physiology.

[27]  G. Breithardt,et al.  Noninvasive risk modeling after myocardial infarction. , 1996, The American journal of cardiology.

[28]  Effects of Physical Training AfterCABG , 2000 .

[29]  Long-term Adaptation of 24-h Heart Rate Variability after Myocardial Infarction , 1992 .

[30]  F. Burzotta,et al.  Prognostic role of heart rate variability in patients with a recent acute myocardial infarction. , 1998, The American journal of cardiology.

[31]  A. Malliani,et al.  Heart rate variability. Standards of measurement, physiological interpretation, and clinical use , 1996 .

[32]  K. Inder,et al.  Randomized trial of a hospital-based exercise training program after acute myocardial infarction: cardiac autonomic effects. , 1997, Journal of the American College of Cardiology.

[33]  G. Malfatto,et al.  Short and long term effects of exercise training on the tonic autonomic modulation of heart rate variability after myocardial infarction. , 1996, European heart journal.

[34]  Long-term adaptation of 24-h heart rate variability after myocardial infarction. The EAMI Study Group. Exercise Training in Anterior Myocardial Infarction. , 1992, Chest.

[35]  Pekka Tiittanen,et al.  Stability over time of short-term heart rate variability , 2005, Clinical Autonomic Research.