TY - JOUR
T1 - Cardiac autonomic responses to volume overload in normal subjects and in patients with dilated cardiomyopathy
AU - Spinelli, L.
AU - Petretta, M.
AU - Marciano, F.
AU - Testa, G.
AU - Rao, M. A E
AU - Volpe, M.
AU - Bonaduce, D.
PY - 1999/10
Y1 - 1999/10
N2 - This study evaluated the effects of acute isotonic volume expansion on heart rate variability (HRV) in 10 patients with dilated cardiomyopathy (DCM) and in 10 age- and sex-matched normal volunteers. Echocardiographic left ventricular volumes and HRV measurements by continuous Holter recording were assessed at baseline, at 60 and 120 min during intravenous saline load (0.9% NaCl, 0.25 ml·kg-1·min-1), and 60 min after infusion was terminated. Data analysis was performed by repeated-measures ANOVA. After volume expansion, left ventricular ejection fraction increased (F = 9.8; P <0.001) in normal subjects and decreased (F = 8.7; P <0.001) in DCM patients. During volume expansion a significant difference was also detectable between the two groups in root-mean-square successive difference (F = 25.2; P <0.001), percentage of differences between successive normal R-R intervals >50 ms (F = 97.6; P <0.001), high-frequency power (F = 50.1; P <0.001), and low- frequency power (F = 41.6; P <0.001), all of which reflect parasympathetic modulation of heart rate; in fact, these measurements increased in normal subjects and decreased in DCM patients. In normal subjects, the increase in HRV measurements during volume expansion suggests a parasympathetic activation, mediated by stimulation of cardiopulmonary and arterial mechanoreceptors. On the contrary, in DCM patients the parasympathetic withdrawal, already detectable at baseline, increases during volume expansion.
AB - This study evaluated the effects of acute isotonic volume expansion on heart rate variability (HRV) in 10 patients with dilated cardiomyopathy (DCM) and in 10 age- and sex-matched normal volunteers. Echocardiographic left ventricular volumes and HRV measurements by continuous Holter recording were assessed at baseline, at 60 and 120 min during intravenous saline load (0.9% NaCl, 0.25 ml·kg-1·min-1), and 60 min after infusion was terminated. Data analysis was performed by repeated-measures ANOVA. After volume expansion, left ventricular ejection fraction increased (F = 9.8; P <0.001) in normal subjects and decreased (F = 8.7; P <0.001) in DCM patients. During volume expansion a significant difference was also detectable between the two groups in root-mean-square successive difference (F = 25.2; P <0.001), percentage of differences between successive normal R-R intervals >50 ms (F = 97.6; P <0.001), high-frequency power (F = 50.1; P <0.001), and low- frequency power (F = 41.6; P <0.001), all of which reflect parasympathetic modulation of heart rate; in fact, these measurements increased in normal subjects and decreased in DCM patients. In normal subjects, the increase in HRV measurements during volume expansion suggests a parasympathetic activation, mediated by stimulation of cardiopulmonary and arterial mechanoreceptors. On the contrary, in DCM patients the parasympathetic withdrawal, already detectable at baseline, increases during volume expansion.
KW - Heart rate variability
KW - Isotonic volume expansion
KW - Left ventricular dysfunction
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M3 - Article
C2 - 10516170
AN - SCOPUS:0032711314
VL - 277
JO - American Journal of Physiology
JF - American Journal of Physiology
SN - 0363-6119
IS - 4 46-4
ER -