Spontaneous Cardiac Baroreflex in Humans
- 1 May 1995
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Hypertension
- Vol. 25 (5), 1058-1068
- https://doi.org/10.1161/01.hyp.25.5.1058
Abstract
Abstract We compared two methods of assessment of baroreflex sensitivity in eight supine healthy volunteers during repeated baseline measurements and various conditions of cardiac autonomic blockade. The spontaneous baroreflex method involved computer scanning of recordings of continuous finger arterial pressure and electrocardiogram to locate sequences of three or more beats in which pressure spontaneously increased or decreased, with parallel changes in pulse intervals. The mean regression slope of all these sequences during each study condition was considered to represent the mean spontaneous baroreflex slope. In the drug-induced method, sigmoidal curves were constructed from data obtained by bolus injections of phenylephrine and nitroprusside; the tangents taken at the resting pressure of each of these curves were compared with the mean spontaneous baroreflex slopes. The two methods yielded slopes that were highly correlated ( r =.96, P <.001), with significant but similar intraindividual baseline variability. Atropine virtually eliminated the baroreflex slope; subsequent addition of propranolol did not alter it further. Propranolol or clonidine alone increased average baroreflex slope to the extent that they increased resting pulse interval ( r =.69 to .83). The spontaneous baroreflex method provides a reliable, noninvasive assessment of human vagal cardiac baroreflex sensitivity within its physiological operating range.Keywords
This publication has 25 references indexed in Scilit:
- Comparison of finger and intra-arterial blood pressure monitoring at rest and during laboratory testing.Hypertension, 1989
- Evaluation of the baroreceptor-heart rate reflex by 24-hour intra-arterial blood pressure monitoring in humans.Hypertension, 1988
- Vagal and sympathetic components of the heart rate range and gain of the baroreceptor-heart rate reflex in conscious ratsJournal of the Autonomic Nervous System, 1987
- STATISTICAL METHODS FOR ASSESSING AGREEMENT BETWEEN TWO METHODS OF CLINICAL MEASUREMENTThe Lancet, 1986
- Beta-adrenergic blockade may prolong life in post-infarction patients in part by increasing vagal cardiac inhibitionMedical Hypotheses, 1984
- Arterial Baroreflexes in HumansPublished by American Geophysical Union (AGU) ,1983
- Effects of Oral Clonidine on Baroreflex Function in Patients with Essential HypertensionSocial psychiatry. Sozialpsychiatrie. Psychiatrie sociale, 1983
- Clonidine and carotid baroreflex in essential hypertension.Hypertension, 1979
- 'Steady-state' properties of the baroreceptor-heart rate reflex in essential hypertension in manClinical and Experimental Pharmacology and Physiology, 1974
- Vagal component of the chronotropic response to baroreceptor stimulation in manAmerican Heart Journal, 1971