Obesity is associated with autonomic nervous system dysfunction. The aim of the study was to evaluate baroreflex sensitivity, an indicator of autonomic nervous function, in 20 obese children and adolescents in comparison with 20 age- and sex-matched nonobese subjects. All subjects were examined in the supine position over a period of 50 min. Systolic blood pressure (SBP) and RR intervals were m...

BACKGROUND Depressed baroreflex sensitivity obtained by means of a phenylephrine test plays a prognostic role in patients with a previous myocardial infarction. Our purpose was to evaluate the correlation and agreement between the baroreflex sensitivity obtained with phenylephrine and that obtained by two noninvasive methods: the alpha-index and sequence analysis. METHODS AND RESULTS The alph...

It has been known for many years that baroreflex sensitivity is lowered in hypertensive patients. There are several known factors implicating this association, e.g. high blood pressure leads to remodeling of the carotid arterial wall, to its stiffness and to a diminished activation of baroreceptors; leptin released from a fatty tissue activates the sympathetic nervous system etc. On the other h...

Decreased vagal activity has been described in acute schizophrenia and might be associated with altered cardiovascular regulation and increased cardiac mortality. The aim of this study was to assess baroreflex sensitivity in the context of psychopathology. Twenty-one acute, psychotic, unmedicated patients with a diagnosis of paranoid schizophrenia were investigated after admission to the hospit...

as the millisecond increase in cycle length per mm Hg rise in systolic pressure. The slope is an index of baroreflex sensitivity and was found to have an average value of 12.8 in 18 subjects without hypertension and 2.8 in 12 others with hypertension. When all results were pooled, there was an inverse relationship between the resting mean arterial pressure and slope of the baroreflex regression...

AIMS To determine whether it is possible to assess baroreflex sensitivity in neonates by studying only spontaneous variation in systolic blood pressure and heart rate. METHODS ECG and non-invasive blood pressure signals were continuously studied in 14 preterm neonates (term 29-32 weeks) and five term neonates (term 40-41 weeks). Non-invasive blood pressure measures were obtained using a Finap...

Baroreflex sensitivity was studied in the same group of conscious rats using vasoactive drugs (phenylephrine and sodium nitroprusside) administered by three different approaches: 1) bolus injection, 2) steady-state (blood pressure (BP) changes produced in steps), 3) ramp infusion (30 s, brief infusion). The heart rate (HR) responses were evaluated by the mean index (mean ratio of all HR changes...

OBJECTIVES This study addressed the relationship between spontaneous baroreflex sensitivity and carotid mechanical properties in a clinical setting. METHODS In 191 normal volunteers (age range 20-60 years, mean 44 ± 13), spontaneous indices of baroreflex regulation were obtained noninvasively in the time (baroreflex slope, BRS) and frequency domains (α index and systolic arterial pressure-RR ...

OBJECTIVE To assess the influence of both sympathetic (plasma noradrenaline concentrations) and parasympathetic (baroreflex activation) tone on survival in patients with congestive heart failure. DESIGN Invasive study with determination of parasympathetic activity and follow up for at least 4.5 years. SUBJECTS 35 patients with sinus rhythm and mild to moderate heart failure (New York Heart ...

Control of heart rate variability via modulation of sympathovagal balance is a key function of nucleus tractus solitarii and the dorsal motor nucleus of the vagus localized in the dorsomedial medulla oblongata. Normal blood pressure regulation involves precise balance of glutamate (Glu)-glutamine-gamma-aminobutyric acid transmitter systems, and angiotensin II modulates these transmitters to pro...