scholarly journals Sequential spectral analysis of 24-hour blood pressure and pulse interval in humans.

Hypertension ◽  
1990 ◽  
Vol 16 (4) ◽  
pp. 414-421 ◽  
Author(s):  
G Parati ◽  
P Castiglioni ◽  
M Di Rienzo ◽  
S Omboni ◽  
A Pedotti ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Spectral Analysis ◽  
Pulse Interval

24 h sequential spectral analysis of arterial blood pressure and pulse interval in free-moving subjects

1989 ◽  
Vol 36 (11) ◽  
pp. 1066-1075 ◽  
Author(s):  
M. Di Rienzo ◽  
P. Castiglioni ◽  
G. Mancia ◽  
G. Parati ◽  
A. Pedotti
Keyword(s):  
Blood Pressure ◽  
Spectral Analysis ◽  
Arterial Blood Pressure ◽  
Pulse Interval ◽  
Arterial Blood

Frequency-dependent baroreflex modulation of blood pressure and heart rate variability in conscious mice

2005 ◽  
Vol 289 (5) ◽  
pp. H1968-H1975 ◽  
Author(s):  
Rubens Fazan ◽  
Mauro de Oliveira ◽  
Valdo José Dias da Silva ◽  
Luis Fernando Joaquim ◽  
Nicola Montano ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Spectral Analysis ◽  
High Frequency ◽  
Low Frequency ◽  
Systolic Arterial Pressure ◽  
Pulse Interval ◽  
Sham Surgery ◽  
Cardiac Receptors

The goal of this study was to determine the baroreflex influence on systolic arterial pressure (SAP) and pulse interval (PI) variability in conscious mice. SAP and PI were measured in C57Bl/6J mice subjected to sinoaortic deafferentation (SAD, n = 21) or sham surgery ( n = 20). Average SAP and PI did not differ in SAD or control mice. In contrast, SAP variance was enhanced (21 ± 4 vs. 9.5 ± 1 mmHg2) and PI variance reduced (8.8 ± 2 vs. 26 ± 6 ms2) in SAD vs. control mice. High-frequency (HF: 1–5 Hz) SAP variability quantified by spectral analysis was greater in SAD (8.5 ± 2.0 mmHg2) compared with control (2.5 ± 0.2 mmHg2) mice, whereas low-frequency (LF: 0.1–1 Hz) SAP variability did not differ between the groups. Conversely, LF PI variability was markedly reduced in SAD mice (0.5 ± 0.1 vs. 10.8 ± 3.4 ms2). LF oscillations in SAP and PI were coherent in control mice (coherence = 0.68 ± 0.05), with changes in SAP leading changes in PI (phase = −1.41 ± 0.06 radians), but were not coherent in SAD mice (coherence = 0.08 ± 0.03). Blockade of parasympathetic drive with atropine decreased average PI, PI variance, and LF and HF PI variability in control ( n = 10) but had no effect in SAD ( n = 6) mice. In control mice, blockade of sympathetic cardiac receptors with propranolol increased average PI and decreased PI variance and LF PI variability ( n = 6). In SAD mice, propranolol increased average PI ( n = 6). In conclusion, baroreflex modulation of PI contributes to LF, but not HF PI variability, and is mediated by both sympathetic and parasympathetic drives in conscious mice.

Applicability of New Techniques in the Assessment of Arterial Baroreflex Sensitivity in the Elderly: A Comparison with Established Pharmacological Methods

1998 ◽  
Vol 94 (3) ◽  
pp. 245-253 ◽  
Author(s):  
Martin A. James ◽  
Ronney B. Panerai ◽  
John F. Potter
Keyword(s):  
Blood Pressure ◽  
Spectral Analysis ◽  
Baroreflex Sensitivity ◽  
The Elderly ◽  
Elderly Subjects ◽  
Pulse Interval ◽  
Systematic Bias ◽  
Arterial Baroreflex ◽  
Clinic Blood Pressure ◽  
Acceptable Agreement

1. There has been considerable interest in techniques recently developed for the study of arterial baroreceptor—cardiac reflex sensitivity based on analysis of spontaneous baroreflex sequences and on spectral analysis. This study examined how these newer techniques agreed with the established pharmacological methods in elderly subjects. 2. In 20 elderly subjects [10 hypertensive (clinic blood pressure 180 ± 4/88 ± 2 mmHg) and 10 normotensive (clinic blood pressure 136 ± 3/73 ± 2 mmHg)], we assessed baroreflex sensitivity from spontaneous sequences of increasing and decreasing blood pressure and pulse interval and their mean, and from spectral analysis to derive α, the index of overall baroreflex gain. Pharmacological baroreflex sensitivity was derived from the blood pressure and pulse interval responses to depressor (sodium nitroprusside) and pressor (phenylephrine) stimuli, and their mean. 3. Baroreflex sensitivity was significantly lower in the hypertensive group by the pharmacological, sequence and spectral methods (all P < 0.05). 4. There was acceptable agreement between pharmacological baroreflex sensitivity and sequences of the same direction, but with some systematic bias. There was also reasonable agreement between pharmacological and spectral baroreflex sensitivity and close agreement without bias between sequence and spectral methods. 5. The newer and established techniques demonstrate acceptable agreement in the elderly, albeit with some systematic bias. Pharmacological methods have enjoyed historical precedence but newer techniques give equivalent results, and are preferable in some circumstances. The newer techniques may be more descriptive of the spontaneous behaviour of the arterial baroreflex at rest rather than under artificially stimulated conditions.

Power spectral analysis of heart rate and blood pressure variability in anaesthetized dogs

1992 ◽  
Vol 146 (2) ◽  
pp. 155-164 ◽  
Author(s):  
A. E. HEDMAN ◽  
J. E. K. HARTIKAINEN ◽  
K. U. O. TAHVANAINEN ◽  
M. O. K. HAKUMÄKI
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Spectral Analysis ◽  
Blood Pressure Variability ◽  
Power Spectral Analysis ◽  
Power Spectral

Effects of spinal cord transection on sympathetic discharge in decerebrate-unanesthetized cats

1989 ◽  
Vol 257 (6) ◽  
pp. R1506-R1511 ◽  
Author(s):  
L. C. Weaver ◽  
R. D. Stein
Keyword(s):  
Blood Pressure ◽  
Spinal Cord ◽  
Heart Rate ◽  
Spectral Analysis ◽  
Spinal Cord Transection ◽  
Renal Nerves ◽  
Frequency Range ◽  
Renal Nerve ◽  
Sympathetic Discharge ◽  
Nerve Discharge

Previous experiments in our laboratory have shown that discharge of splenic, mesenteric, and splanchnic nerves is well maintained after spinal cord transection in chloralose-anesthetized cats (8, 9, 11). The primary purpose of this investigation was to determine if maintained sympathetic discharge could be observed after spinal transection in the absence of chloralose anesthesia. In cats anesthetized with alphaxalone-alphadolone, changes in splanchnic discharge, blood pressure, and heart rate caused by decerebration and removal of the forebrain were observed. This procedure decreased blood pressure, increased heart rate, and had no immediate effect on sympathetic discharge or its rhythm (assessed by power density spectral analysis). One hour after decerebration and termination of anesthesia, splanchnic discharge had increased by approximately 36%. Next, effects of spinal cord transection on discharge of splanchnic, mesenteric, and renal nerves were observed in the decerebrate-unanesthetized cats. Splanchnic discharge decreased by 50%, mesenteric nerve discharge was unchanged, and renal nerve discharge decreased by 97%. Therefore, splanchnic nerve discharge was not as well maintained in decerebrate-unanesthetized cats as it had been in chloralose-anesthetized animals, and the remaining splanchnic discharge appeared to affect mesenteric nerves preferentially. Finally, spectral analysis of the splanchnic discharge demonstrated that before cord transection, most of the signal was in the 0- to 6-Hz frequency range, whereas after transection the proportion of signal in this frequency range was significantly reduced and the proportion in higher frequencies (7-25 Hz) was significantly increased. This loss of low-frequency rhythmicity is consistent with findings in our previous studies in chloralose-anesthetized cats.

Evaluation of baroreceptor reflex by blood pressure monitoring in unanesthetized cats

1988 ◽  
Vol 254 (2) ◽  
pp. H377-H383 ◽  
Author(s):  
G. Bertinieri ◽  
M. Di Rienzo ◽  
A. Cavallazzi ◽  
A. U. Ferrari ◽  
A. Pedotti ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Regression Coefficient ◽  
Blood Pressure Monitoring ◽  
Sinus Node ◽  
Pulse Interval ◽  
Pressure Monitoring ◽  
Physiological Conditions ◽  
Average Variation

The arterial baroreceptor control of the sinus node operating in unanesthetized conditions was evaluated in 10 cats in which blood pressure was recorded intra-arterially and scanned by a computer to identify the "spontaneous" sequences of three or more consecutive beats in which systolic blood pressure (SBP) progressively rose and pulse interval (PI) progressively lengthened (type 1 sequences) or SBP progressively fell and PI progressively shortened (type 2 sequences). Many type 1 and 2 three-beat sequences were found; four-, five-, and six-beat sequences of either type were progressively less common, and sequences longer than six beats were almost never identified. The regression coefficient was 30% greater for type 1 than for type 2 sequences. However a prominent feature of either regression coefficient was a wide scattering in each cat (average variation coefficient 50.9 +/- 5.5%). The regression coefficient values were related to some extent to the PI but not to the SBP existing at the beginning of the sequence. Sinoaortic denervation dramatically reduced the number of sequences of either type. These data validate a method for collecting a large number of observations on the baroreceptor-heart rate reflex in physiological conditions. This method may improve understanding of baroreflex involvement in integrated cardiovascular regulation.

Biofeedback of R-wave to Pulse Interval Produces Differential Learning of Blood Pressure Control

1996 ◽  
Vol 25 (1) ◽  
pp. 17-25
Author(s):  
Harald Rau ◽  
Rolf Weitkunat ◽  
Stuart Brody ◽  
Michael Bührer ◽  
Monika Jonak ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Control ◽  
Pressure Control ◽  
Pulse Interval ◽  
Differential Learning
Sign in / Sign up

Export Citation Format

Share Document