Circulation Research, Vol 59, 178-193, Copyright © 1986 by American Heart Association

ARTICLES

Power spectral analysis of heart rate and arterial pressure variabilities as a marker of sympatho-vagal interaction in man and conscious dog

M Pagani, F Lombardi, S Guzzetti, O Rimoldi, R Furlan, P Pizzinelli, G Sandrone, G Malfatto, S Dell'Orto and E Piccaluga

In 57 normal subjects (age 20-60 years), we analyzed the spontaneous beat-to-beat oscillation in R-R interval during control recumbent position, 90 degrees upright tilt, controlled respiration (n = 16) and acute (n = 10) and chronic (n = 12) beta-adrenergic receptor blockade. Automatic computer analysis provided the autoregressive power spectral density, as well as the number and relative power of the individual components. The power spectral density of R-R interval variability contained two major components in power, a high frequency at approximately 0.25 Hz and a low frequency at approximately 0.1 Hz, with a normalized low frequency:high frequency ratio of 3.6 +/- 0.7. With tilt, the low-frequency component became largely predominant (90 +/- 1%) with a low frequency:high frequency ratio of 21 +/- 4. Acute beta- adrenergic receptor blockade (0.2 mg/kg IV propranolol) increased variance at rest and markedly blunted the increase in low frequency and low frequency:high frequency ratio induced by tilt. Chronic beta- adrenergic receptor blockade (0.6 mg/kg p.o. propranolol, t.i.d.), in addition, reduced low frequency and increased high frequency at rest, while limiting the low frequency:high frequency ratio increase produced by tilt. Controlled respiration produced at rest a marked increase in the high-frequency component, with a reduction of the low-frequency component and of the low frequency:high frequency ratio (0.7 +/- 0.1); during tilt, the increase in the low frequency:high frequency ratio (8.3 +/- 1.6) was significantly smaller. In seven additional subjects in whom direct high-fidelity arterial pressure was recorded, simultaneous R-R interval and arterial pressure variabilities were examined at rest and during tilt. Also, the power spectral density of arterial pressure variability contained two major components, with a relative low frequency:high frequency ratio at rest of 2.8 +/- 0.7, which became 17 +/- 5 with tilt. These power spectral density components were numerically similar to those observed in R-R variability. Thus, invasive and noninvasive studies provided similar results. More direct information on the role of cardiac sympathetic nerves on R-R and arterial pressure variabilities was derived from a group of experiments in conscious dogs before and after bilateral stellectomy. Under control conditions, high frequency was predominant and low frequency was very small or absent, owing to a predominant vagal tone. During a 9% decrease in arterial pressure obtained with IV nitroglycerin, there was a marked increase in low frequency, as a result of reflex sympathetic activation.(ABSTRACT TRUNCATED AT 400 WORDS)

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				D. S. Ditor, M. V. Kamath, M. J. MacDonald, J. Bugaresti, N. McCartney, and A. L. Hicks Effects of body weight-supported treadmill training on heart rate variability and blood pressure variability in individuals with spinal cord injury J Appl Physiol, April 1, 2005; 98(4): 1519 - 1525. [Abstract] [Full Text] [PDF]

				Y. Chen, L. F. Joaquim, V. M. Farah, R. B. Wichi, R. Fazan Jr., H. C. Salgado, and M. Morris Cardiovascular autonomic control in mice lacking angiotensin AT1a receptors Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2005; 288(4): R1071 - R1077. [Abstract] [Full Text] [PDF]

				A. Pichon, C. de Bisschop, V. Diaz, and A. Denjean Parasympathetic Airway Response and Heart Rate Variability Before and at the End of Methacholine Challenge Chest, January 1, 2005; 127(1): 23 - 29. [Abstract] [Full Text] [PDF]

				O. Ozdemir, O. Alyan, M. Soylu, F. Metin, F. Kacmaz, A. D. Demir, B. Geyik, D. Aras, H. Sasmaz, and S. Korkmaz Improvement in sympatho-vagal imbalance and heart rate variability in patients with mitral stenosis after percutaneous balloon commissurotomy Europace, January 1, 2005; 7(3): 204 - 210. [Abstract] [Full Text] [PDF]

				C. Cogliati, S. Colombo, T. G. Ruscone, D. Gruosso, A. Porta, N. Montano, A. Malliani, and R. Furlan Acute {beta}-Blockade Increases Muscle Sympathetic Activity and Modifies Its Frequency Distribution Circulation, November 2, 2004; 110(18): 2786 - 2791. [Abstract] [Full Text] [PDF]

				B. Stemper, L. Bernardi, F. B. Axelrod, G. Welsch, C. Passino, and M. J. Hilz Sympathetic and parasympathetic baroreflex dysfunction in familial dysautonomia Neurology, October 26, 2004; 63(8): 1427 - 1431. [Abstract] [Full Text] [PDF]

				S. Wakabayashi and Y. Aso Adiponectin Concentrations in Sera From Patients With Type 2 Diabetes Are Negatively Associated With Sympathovagal Balance as Evaluated by Power Spectral Analysis of Heart Rate Variation Diabetes Care, October 1, 2004; 27(10): 2392 - 2397. [Abstract] [Full Text] [PDF]

				S. C. Tjen-A-Looi, P. Li, and J. C. Longhurst Medullary substrate and differential cardiovascular responses during stimulation of specific acupoints Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2004; 287(4): R852 - R862. [Abstract] [Full Text] [PDF]

				O. Manfrini, G. Morgagni, C. Pizzi, F. Fontana, and R. Bugiardini Changes in autonomic nervous system activity: spontaneous versus balloon-induced myocardial ischaemia Eur. Heart J., September 1, 2004; 25(17): 1502 - 1508. [Abstract] [Full Text] [PDF]

				M. Tanaka, T. Goyagi, T. Kimura, and T. Nishikawa The Effects of Cervical and Lumbar Epidural Anesthesia on Heart Rate Variability and Spontaneous Sequence Baroreflex Sensitivity Anesth. Analg., September 1, 2004; 99(3): 924 - 929. [Abstract] [Full Text] [PDF]

				D. D. O'Leary, J. K. Shoemaker, M. R. Edwards, and R. L. Hughson Spontaneous beat-by-beat fluctuations of total peripheral and cerebrovascular resistance in response to tilt Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2004; 287(3): R670 - R679. [Abstract] [Full Text] [PDF]

				J. A. Armour Cardiac neuronal hierarchy in health and disease Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2004; 287(2): R262 - R271. [Abstract] [Full Text] [PDF]

				R. Burattini, P. Borgdorff, and N. Westerhof The baroreflex is counteracted by autoregulation, thereby preventing circulatory instability Exp Physiol, July 1, 2004; 89(4): 397 - 405. [Abstract] [Full Text] [PDF]

				M. Tanaka, T. Kimura, T. Goyagi, and T. Nishikawa Gender differences in baroreflex response and heart rate variability in anaesthetized humans Br. J. Anaesth., June 1, 2004; 92(6): 831 - 835. [Abstract] [Full Text] [PDF]

				W. H. Cooke, J. R. Carter, and T. A. Kuusela Human cerebrovascular and autonomic rhythms during vestibular activation Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2004; 286(5): R838 - R843. [Abstract] [Full Text] [PDF]

				J. Tank, J. Jordan, A. Diedrich, M. Obst, R. Plehm, F. C. Luft, and V. Gross Clonidine Improves Spontaneous Baroreflex Sensitivity in Conscious Mice Through Parasympathetic Activation Hypertension, May 1, 2004; 43(5): 1042 - 1047. [Abstract] [Full Text] [PDF]

				J. Fletcher, A. N. Buch, H. C. Routledge, S. Chowdhary, J. H. Coote, and J. N. Townend Acute aldosterone antagonism improves cardiac vagal control in humans J. Am. Coll. Cardiol., April 7, 2004; 43(7): 1270 - 1275. [Abstract] [Full Text] [PDF]

				F. Iellamo, F. Placidi, M. G. Marciani, A. Romigi, M. Tombini, S. Aquilani, M. Massaro, A. Galante, and J. M. Legramante Baroreflex Buffering of Sympathetic Activation During Sleep: Evidence From Autonomic Assessment of Sleep Macroarchitecture and Microarchitecture Hypertension, April 1, 2004; 43(4): 814 - 819. [Abstract] [Full Text] [PDF]