(Hypertension. 2003;41:1240.)
© 2003 American Heart Association, Inc.
Scientific Contributions |
From Dipartimento di Scienze dellInvecchiamento, Policlinico Umberto I, Università "La Sapienza," Rome, Italy.
Correspondence to Dr Gianfranco Piccirillo, Dipartimento di Scienze dellInvecchiamento, I Clinica Medica, Policlinico Umberto I, 00161 Rome, Italy. E-mail gianfranco.piccirillo{at}uniroma1.it
Chronic heart failure (CHF) reduces baroreflex sensitivity. Low baroreflex sensitivity, a risk factor for sudden death, could arise partly from CHF-dependent endothelial dysfunction. Vitamin C at high doses has a protective role against CHF-related endothelial damage. This study was conducted to investigate the effect of vitamin C on baroreflex sensitivity in CHF. A study group of 33 subjects with CHF secondary to postischemic dilated cardiomyopathy with an ejection fraction
35% and a control group (11 subjects) underwent assessment of baroreflex sensitivity by the phenylephrine method and an autonomic nervous system study by power spectral analysis. Variables were assessed after infusion of placebo and high doses of vitamin C (2.5 mg). In subjects with CHF, baroreflex sensitivity was significantly higher after vitamin C than after placebo infusion (placebo: 4.1±0.4 versus vitamin C: 5.3±0.5 ms/mm Hg, P<0.001). Low-frequency of R-R (LFRR), expressed in normalized units (NU) (P<0.05); LF/high-frequency (HF) ratio (P<0.05), and LF of SBP (LFSBP) decreased significantly; HF power (P<0.05), and
-HF (P<0.001) increased. Conversely, in the control group, baroreflex sensitivity and other spectral variables measured at baseline, after placebo, and after vitamin C infusion remained statistically unchanged (placebo: 10.2±0.1 versus vitamin C: 10.0±0.2 ms/mm Hg, NS). Acute administration of vitamin C at high doses improves baroreflex sensitivity and vagal sinus modulation in patients with CHF. This finding could have notable clinical and therapeutic implications. Key issues to understand are whether the beneficial effect persists during chronic administration and whether it helps to improve survival.
Key Words: autonomic nervous system baroreflex vitamins heart failure endothelium vasoconstriction
This article has been cited by other articles:
![]() |
E. Peeters, A. Neyt, F. Beckers, S. De Smet, A. E. Aubert, and R. Geers Influence of supplemental magnesium, tryptophan, vitamin C, and vitamin E on stress responses of pigs to vibration J Anim Sci, July 1, 2005; 83(7): 1568 - 1580. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. A. Mullan, C. N. Ennis, H. J. P. Fee, I. S. Young, and D. R. McCance Protective effects of ascorbic acid on arterial hemodynamics during acute hyperglycemia Am J Physiol Heart Circ Physiol, September 1, 2004; 287(3): H1262 - H1268. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. D. Monahan, I. Eskurza, and D. R. Seals Ascorbic acid increases cardiovagal baroreflex sensitivity in healthy older men Am J Physiol Heart Circ Physiol, June 1, 2004; 286(6): H2113 - H2117. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. K. Nightingale, M. Schmitt, M. P. Frenneaux, G. Piccirillo, M. Nocco, A. Moise, M. Lionetti, C. Naso, and S. D. C. V. Marigliano Letter: Vitamin C in Heart Failure: Hype or Hope? Hypertension, February 1, 2004; e6(2): . [Full Text] [PDF] |
||||
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2003 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |