Evidence for an intrinsic mechanism regulating heart rate variability in the transplanted and the intact heart during submaximal dynamic exercise?

L. Bernardi, F. Salvucci, R. Suardi, P. L. Solda, A. Calciati, S. Perlini, C. Falcone, L. Ricciardi

Research output: Contribution to journalArticle

Abstract

Study objective: The aim was to assess the changes in sympatho-vagal balance which occur with exercise. Design: The power spectrum of RR interval fluctuations (low frequency [LF] and high frequency components [HF]) was determined before, during, and after graded work load exercise on a cycle ergometer. The power spectrum of the respiratory signal, oxygen consumption, and respiratory volumes were also evaluated. In all subjects HF was considered to be an index of respiratory sinus arrhythmia. In normal subjects HF and LF were considered to be indices of relative vagal and sympathetic activity, respectively, whereas in heart transplant subjects HF was considered as a respiratory modulation of the intrinsic heart rate, and not dependent on autonomic tone. Heart rate variability was evaluated as RR interval variance. Subjects: 15 normal subjects (six trained cyclists and nine healthy sedentary subjects) and six orthotopic heart transplant recipients took part in the study. Measurements and main results: During the first part of exercise, heart rate increased, RR interval variance decreased, HF decreased, and the relative amount of LF increased both in sedentary and athletic subjects, suggesting a relative increase in sympathetic tone. However, when approaching peak exercise, while heart rate further increased and the variance slightly decreased, the relative proportion of LF decreased and HF proportionally increased. At peak exercise HF accouned for 99.9% of heart rate variability in athletic subjects and for 88.9% in sedentary subjects (p <0.001 v baseline and v LF in both groups). In heart transplant subjects both the variance and the HF increased from the beginning of exercise (p <0.05), and showed a direct correlation with ventilatory variables and an inverse correlation with heart rate (r = 0.794, p <0.001, multiple regression analysis). No measurable LF components could be obtained in these subjects. During recovery, while the heart rate decreased had the RR interval variance increased, there was a relative increase in LF and a relative decrease in HF in normal subjects (either sedentary or athletic). Similarly, in heart transplant subjects, there was a decrease in HF during recovery. Thus the increase in HF at peak exercise in normal subjects contrasts with all the other data which suggest a prevalence in sympathetic tone during the entire exercise and the early recovery period, but appears similar to the increase in HF observed in heart transplant subjects due to the effect of increased ventilation during exercise. Conclusions: These findings suggest that at peak exercise a non-autonomic mechanism, possibly intrinsic to the heart muscle, may determine heart rate fluctuations in synchrony with ventilation in the intact as well as in the denervated human heart.

Original languageEnglish
Pages (from-to)969-981
Number of pages13
JournalCardiovascular Research
Volume24
Issue number12
Publication statusPublished - 1990

Fingerprint

Heart Rate
Exercise
Sports
Transplants
Ventilation
Workload
Oxygen Consumption
Myocardium
Healthy Volunteers
Regression Analysis

Keywords

  • autonomic nervous system
  • exercise test
  • heart rate variability
  • heart transplantation
  • intrinsic heart rate
  • power spectral analysis

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Evidence for an intrinsic mechanism regulating heart rate variability in the transplanted and the intact heart during submaximal dynamic exercise? / Bernardi, L.; Salvucci, F.; Suardi, R.; Solda, P. L.; Calciati, A.; Perlini, S.; Falcone, C.; Ricciardi, L.

In: Cardiovascular Research, Vol. 24, No. 12, 1990, p. 969-981.

Research output: Contribution to journalArticle

Bernardi, L, Salvucci, F, Suardi, R, Solda, PL, Calciati, A, Perlini, S, Falcone, C & Ricciardi, L 1990, 'Evidence for an intrinsic mechanism regulating heart rate variability in the transplanted and the intact heart during submaximal dynamic exercise?', Cardiovascular Research, vol. 24, no. 12, pp. 969-981.
Bernardi, L. ; Salvucci, F. ; Suardi, R. ; Solda, P. L. ; Calciati, A. ; Perlini, S. ; Falcone, C. ; Ricciardi, L. / Evidence for an intrinsic mechanism regulating heart rate variability in the transplanted and the intact heart during submaximal dynamic exercise?. In: Cardiovascular Research. 1990 ; Vol. 24, No. 12. pp. 969-981.
@article{fcde7b329fb342e48703a70dcf0d02f1,
title = "Evidence for an intrinsic mechanism regulating heart rate variability in the transplanted and the intact heart during submaximal dynamic exercise?",
abstract = "Study objective: The aim was to assess the changes in sympatho-vagal balance which occur with exercise. Design: The power spectrum of RR interval fluctuations (low frequency [LF] and high frequency components [HF]) was determined before, during, and after graded work load exercise on a cycle ergometer. The power spectrum of the respiratory signal, oxygen consumption, and respiratory volumes were also evaluated. In all subjects HF was considered to be an index of respiratory sinus arrhythmia. In normal subjects HF and LF were considered to be indices of relative vagal and sympathetic activity, respectively, whereas in heart transplant subjects HF was considered as a respiratory modulation of the intrinsic heart rate, and not dependent on autonomic tone. Heart rate variability was evaluated as RR interval variance. Subjects: 15 normal subjects (six trained cyclists and nine healthy sedentary subjects) and six orthotopic heart transplant recipients took part in the study. Measurements and main results: During the first part of exercise, heart rate increased, RR interval variance decreased, HF decreased, and the relative amount of LF increased both in sedentary and athletic subjects, suggesting a relative increase in sympathetic tone. However, when approaching peak exercise, while heart rate further increased and the variance slightly decreased, the relative proportion of LF decreased and HF proportionally increased. At peak exercise HF accouned for 99.9{\%} of heart rate variability in athletic subjects and for 88.9{\%} in sedentary subjects (p <0.001 v baseline and v LF in both groups). In heart transplant subjects both the variance and the HF increased from the beginning of exercise (p <0.05), and showed a direct correlation with ventilatory variables and an inverse correlation with heart rate (r = 0.794, p <0.001, multiple regression analysis). No measurable LF components could be obtained in these subjects. During recovery, while the heart rate decreased had the RR interval variance increased, there was a relative increase in LF and a relative decrease in HF in normal subjects (either sedentary or athletic). Similarly, in heart transplant subjects, there was a decrease in HF during recovery. Thus the increase in HF at peak exercise in normal subjects contrasts with all the other data which suggest a prevalence in sympathetic tone during the entire exercise and the early recovery period, but appears similar to the increase in HF observed in heart transplant subjects due to the effect of increased ventilation during exercise. Conclusions: These findings suggest that at peak exercise a non-autonomic mechanism, possibly intrinsic to the heart muscle, may determine heart rate fluctuations in synchrony with ventilation in the intact as well as in the denervated human heart.",
keywords = "autonomic nervous system, exercise test, heart rate variability, heart transplantation, intrinsic heart rate, power spectral analysis",
author = "L. Bernardi and F. Salvucci and R. Suardi and Solda, {P. L.} and A. Calciati and S. Perlini and C. Falcone and L. Ricciardi",
year = "1990",
language = "English",
volume = "24",
pages = "969--981",
journal = "Cardiovascular Research",
issn = "0008-6363",
publisher = "Oxford University Press",
number = "12",

}

TY - JOUR

T1 - Evidence for an intrinsic mechanism regulating heart rate variability in the transplanted and the intact heart during submaximal dynamic exercise?

AU - Bernardi, L.

AU - Salvucci, F.

AU - Suardi, R.

AU - Solda, P. L.

AU - Calciati, A.

AU - Perlini, S.

AU - Falcone, C.

AU - Ricciardi, L.

PY - 1990

Y1 - 1990

N2 - Study objective: The aim was to assess the changes in sympatho-vagal balance which occur with exercise. Design: The power spectrum of RR interval fluctuations (low frequency [LF] and high frequency components [HF]) was determined before, during, and after graded work load exercise on a cycle ergometer. The power spectrum of the respiratory signal, oxygen consumption, and respiratory volumes were also evaluated. In all subjects HF was considered to be an index of respiratory sinus arrhythmia. In normal subjects HF and LF were considered to be indices of relative vagal and sympathetic activity, respectively, whereas in heart transplant subjects HF was considered as a respiratory modulation of the intrinsic heart rate, and not dependent on autonomic tone. Heart rate variability was evaluated as RR interval variance. Subjects: 15 normal subjects (six trained cyclists and nine healthy sedentary subjects) and six orthotopic heart transplant recipients took part in the study. Measurements and main results: During the first part of exercise, heart rate increased, RR interval variance decreased, HF decreased, and the relative amount of LF increased both in sedentary and athletic subjects, suggesting a relative increase in sympathetic tone. However, when approaching peak exercise, while heart rate further increased and the variance slightly decreased, the relative proportion of LF decreased and HF proportionally increased. At peak exercise HF accouned for 99.9% of heart rate variability in athletic subjects and for 88.9% in sedentary subjects (p <0.001 v baseline and v LF in both groups). In heart transplant subjects both the variance and the HF increased from the beginning of exercise (p <0.05), and showed a direct correlation with ventilatory variables and an inverse correlation with heart rate (r = 0.794, p <0.001, multiple regression analysis). No measurable LF components could be obtained in these subjects. During recovery, while the heart rate decreased had the RR interval variance increased, there was a relative increase in LF and a relative decrease in HF in normal subjects (either sedentary or athletic). Similarly, in heart transplant subjects, there was a decrease in HF during recovery. Thus the increase in HF at peak exercise in normal subjects contrasts with all the other data which suggest a prevalence in sympathetic tone during the entire exercise and the early recovery period, but appears similar to the increase in HF observed in heart transplant subjects due to the effect of increased ventilation during exercise. Conclusions: These findings suggest that at peak exercise a non-autonomic mechanism, possibly intrinsic to the heart muscle, may determine heart rate fluctuations in synchrony with ventilation in the intact as well as in the denervated human heart.

AB - Study objective: The aim was to assess the changes in sympatho-vagal balance which occur with exercise. Design: The power spectrum of RR interval fluctuations (low frequency [LF] and high frequency components [HF]) was determined before, during, and after graded work load exercise on a cycle ergometer. The power spectrum of the respiratory signal, oxygen consumption, and respiratory volumes were also evaluated. In all subjects HF was considered to be an index of respiratory sinus arrhythmia. In normal subjects HF and LF were considered to be indices of relative vagal and sympathetic activity, respectively, whereas in heart transplant subjects HF was considered as a respiratory modulation of the intrinsic heart rate, and not dependent on autonomic tone. Heart rate variability was evaluated as RR interval variance. Subjects: 15 normal subjects (six trained cyclists and nine healthy sedentary subjects) and six orthotopic heart transplant recipients took part in the study. Measurements and main results: During the first part of exercise, heart rate increased, RR interval variance decreased, HF decreased, and the relative amount of LF increased both in sedentary and athletic subjects, suggesting a relative increase in sympathetic tone. However, when approaching peak exercise, while heart rate further increased and the variance slightly decreased, the relative proportion of LF decreased and HF proportionally increased. At peak exercise HF accouned for 99.9% of heart rate variability in athletic subjects and for 88.9% in sedentary subjects (p <0.001 v baseline and v LF in both groups). In heart transplant subjects both the variance and the HF increased from the beginning of exercise (p <0.05), and showed a direct correlation with ventilatory variables and an inverse correlation with heart rate (r = 0.794, p <0.001, multiple regression analysis). No measurable LF components could be obtained in these subjects. During recovery, while the heart rate decreased had the RR interval variance increased, there was a relative increase in LF and a relative decrease in HF in normal subjects (either sedentary or athletic). Similarly, in heart transplant subjects, there was a decrease in HF during recovery. Thus the increase in HF at peak exercise in normal subjects contrasts with all the other data which suggest a prevalence in sympathetic tone during the entire exercise and the early recovery period, but appears similar to the increase in HF observed in heart transplant subjects due to the effect of increased ventilation during exercise. Conclusions: These findings suggest that at peak exercise a non-autonomic mechanism, possibly intrinsic to the heart muscle, may determine heart rate fluctuations in synchrony with ventilation in the intact as well as in the denervated human heart.

KW - autonomic nervous system

KW - exercise test

KW - heart rate variability

KW - heart transplantation

KW - intrinsic heart rate

KW - power spectral analysis

UR - http://www.scopus.com/inward/record.url?scp=0025603062&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025603062&partnerID=8YFLogxK

M3 - Article

C2 - 2097063

VL - 24

SP - 969

EP - 981

JO - Cardiovascular Research

JF - Cardiovascular Research

SN - 0008-6363

IS - 12

ER -