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Your search keyword '"Rossato, Gianluca"' showing total 7 results
Start Over Author "Rossato, Gianluca" Topic baroreflex
7 results on '"Rossato, Gianluca"'

1. An Empirical Mode Decomposition Approach to Assess the Strength of Heart Period-Systolic Arterial Pressure Variability Interactions.

Author

Bari V, Cairo B, De Maria B, Tonon D, Rossato G, Faes L, and Porta A

Subjects
Blood Pressure, Heart, Heart Rate, Male, Arterial Pressure, Baroreflex
Abstract

This work proposes an empirical mode decomposition (EMD) method to assess the strength of the interactions between heart period (HP) and systolic arterial pressure (SAP) variability. EMD was exploited to decompose the original series (OR) into its first, and fastest, intrinsic mode function (IMF1) and the residual (RES) computed by subtracting the IMF1 from OR. EMD procedure was applied to both HP and SAP variability series. Then, the cross correlation function (CCF) was computed over OR, IMF1 and RES series derived from HP and SAP variability in 13 healthy subjects (age 27±8 yrs, 5 males) at rest in supine position (REST) and during head-up tilt (TILT). The first CCF maximum at negative time lags and the first CCF minimum at positive time lags were taken respectively as indexes of the coupling along the feedback baroreflex and feedforward mechanical arms of HP-SAP closed-loop control. Results showed that the coupling strength is increased during TILT on both arms and this result holds on REST. At REST the coupling along both arms was stronger when computed over IMF1 because interactions were mainly governed by respiration. This result was not observed during TILT possibly due to the reduced importance of respiration compared to other mechanisms acting at slower time scales. The proposed method allowed the investigation of the strength of HP-SAP variability interactions according to the time scales of the physiological mechanisms.The proposed EMD-based method allows the quantification of the strength of the HP-SAP closed-loop variability interactions according to the different time scales of respiration and slower baroreflex-mediated reflexes.

Published
2020
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2. Strength and Latency of the HP-SAP Closed Loop Variability Interactions in Subjects Prone to Develop Postural Syncope .

Author

Bari V, Cairo B, Vaini E, Maria B, Tonon D, Rossato G, Faes L, and Porta A

Subjects
Adult, Blood Pressure, Computer Simulation, Heart Rate, Humans, Male, Syncope, Young Adult, Baroreflex, Heart
Abstract

The coupling and latency between heart period (HP) and systolic arterial pressure (SAP) variability can be investigated along the two arms of the HP-SAP closed loop, namely along the baroreflex feedback from SAP to HP, and along the feedforward pathway from HP to SAP. This study investigates the HP-SAP closed loop variability interactions through cross-correlation function (CCF). Coupling strength and delay between HP and SAP variability series were monitored in 13 subjects prone to develop orthostatic syncope (SYNC, 28±9 yrs, 5 males) and in 13 subjects with no history of postural syncope (noSYNC, age: 27±8 yrs, 5 males). Analysis was carried out at rest in supine position (REST) and during head-up tilt (TILT) at 60 degrees. The null hypothesis of HP-SAP uncoupling was tested through a surrogate analysis associating the HP series of a subject with a SAP sequence of a different one. Results showed that during TILT the coupling strength increased along the baroreflex and latency augmented along the mechanical feedforward pathway exclusively in noSYNC subjects. Finally, closed loop HP-SAP interactions were detected in about one third of subjects and the situation of full uncoupling was rarely found. CCF analysis was found to be a straightforward and easily applicable method to investigate HP-SAP control deserving a direct comparison with more sophisticated signal processing tools assessing causality.

Published
2019
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4. Investigating the mechanisms of cardiovascular and cerebrovascular regulation in orthostatic syncope through an information decomposition strategy.

Author

Faes, Luca, Porta, Alberto, Rossato, Gianluca, Adami, Alessandro, Tonon, Davide, Corica, Antonio, and Nollo, Giandomenico

Subjects
*BLOOD flow measurement, *CARDIOVASCULAR system physiology, *CEREBRAL circulation, *HYPOTENSION, *SYNCOPE, *BLOOD pressure measurement
Abstract

Abstract: Some previous evidence suggests that postural related syncope is associated with defective mechanisms of cerebrovascular (CB) and cardiovascular (CV) control. We characterized the information processing in short-term CB regulation, from the variability of mean cerebral blood flow velocity (CBFV) and mean arterial pressure (AP), and in CV regulation, from the variability of heart period (HP) and systolic AP (SAP), in ten young subjects developing orthostatic syncope in response to prolonged head-up tilt testing. We exploited a novel information-theoretic approach that decomposes the information associated with a variability series into three amounts: the information stored in the series, the information transferred to the series from another series, and the information unexplained by the knowledge of both series. With this approach we were able to show that, compared with the first minutes after head-up tilt, in the period preceding the syncope event (i) the information stored in CBFV variability decreased significantly while the information transferred to CBFV from AP variability increased significantly; (ii) the information storage of HP was kept high but the information transferred to HP from SAP variability decreased significantly. These patterns of information processing suggest that presyncope occurs with a loss both of CB regulation, described by the reduced ability of CBFV of buffering AP fluctuations, and of CV regulation, described by the reduced baroreflex modulation from SAP to HP. We believe that the utilization of tools from the field of information dynamics may give an integrated view of the mechanisms of CB and CV regulation in normal and diseased states, and also provide a deeper understanding of findings revealed by more traditional techniques. [Copyright &y& Elsevier]

Published
2013
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5. Spectral decomposition of cerebrovascular and cardiovascular interactions in patients prone to postural syncope and healthy controls

Author

Riccardo Pernice, Laura Sparacino, Vlasta Bari, Francesca Gelpi, Beatrice Cairo, Gorana Mijatovic, Yuri Antonacci, Davide Tonon, Gianluca Rossato, Michal Javorka, Alberto Porta, Luca Faes, Pernice, Riccardo, Sparacino, Laura, Bari, Vlasta, Gelpi, Francesca, Cairo, Beatrice, Mijatovic, Gorana, Antonacci, Yuri, Tonon, Davide, Rossato, Gianluca, Javorka, Michal, Porta, Alberto, and Faes, Luca

Subjects
Endocrine and Autonomic Systems, Time series analysis, Blood Pressure, Heart, Baroreflex, Cardiovascular System, Syncope, Cerebral autoregulation, Cellular and Molecular Neuroscience, Heart Rate, Autoregressive models, Cardiovascular control, Cerebrovascular Circulation, Granger causality, Settore ING-INF/06 - Bioingegneria Elettronica e Informatica, Humans, Neurology (clinical), Spectral decomposition
Abstract

We present a framework for the linear parametric analysis of pairwise interactions in bivariate time series in the time and frequency domains, which allows the evaluation of total, causal and instantaneous interactions and connects time- and frequency-domain measures. The framework is applied to physiological time series to investigate the cerebrovascular regulation from the variability of mean cerebral blood flow velocity (CBFV) and mean arterial pressure (MAP), and the cardiovascular regulation from the variability of heart period (HP) and systolic arterial pressure (SAP). We analyze time series acquired at rest and during the early and late phase of head-up tilt in subjects developing orthostatic syncope in response to prolonged postural stress, and in healthy controls. The spectral measures of total, causal and instantaneous coupling between HP and SAP, and between MAP and CBFV, are averaged in the low-frequency band of the spectrum to focus on specific rhythms, and over all frequencies to get time-domain measures. The analysis of cardiovascular interactions indicates that postural stress induces baroreflex involvement, and its prolongation induces baroreflex dysregulation in syncope subjects. The analysis of cerebrovascular interactions indicates that the postural stress enhances the total coupling between MAP and CBFV, and challenges cerebral autoregulation in syncope subjects, while the strong sympathetic activation elicited by prolonged postural stress in healthy controls may determine an increased coupling from CBFV to MAP during late tilt. These results document that the combination of time-domain and spectral measures allows us to obtain an integrated view of cardiovascular and cerebrovascular regulation in healthy and diseased subjects.

Published
2021

6. Cerebrovascular and cardiovascular variability interactions investigated through conditional joint transfer entropy in subjects prone to postural syncope

Author

Gianluca Rossato, Davide Tonon, Beatrice De Maria, Claudio Enrico Mazzucco, Alberto Porta, Giandomenico Nollo, Luca Faes, Vlasta Bari, Bari, Vlasta, De Maria, Beatrice, Mazzucco, Claudio Enrico, Rossato, Gianluca, Tonon, Davide, Nollo, Giandomenico, Faes, Luca, and Porta, Alberto

Subjects
Adult, Male, medicine.medical_specialty, Mean arterial pressure, Supine position, cerebral autoregulation, Adolescent, Physiology, Ultrasonography, Doppler, Transcranial, Entropy, Biomedical Engineering, Biophysics, 030204 cardiovascular system & hematology, Baroreflex, Cerebral autoregulation, Syncope, 03 medical and health sciences, Electrocardiography, Young Adult, 0302 clinical medicine, head-up tilt, Heart Rate, Physiology (medical), Internal medicine, information transfer, medicine, Heart rate variability, Humans, baroreflex, Arterial Pressure, business.industry, autonomic nervous system, heart rate variability, Signal Processing, Computer-Assisted, Transcranial Doppler, Plethysmography, Blood pressure, Biophysic, Cerebral blood flow, postural syncope, Anesthesia, Cerebrovascular Circulation, Settore ING-INF/06 - Bioingegneria Elettronica E Informatica, Cardiology, Female, Disease Susceptibility, business, 030217 neurology & neurosurgery, Human
Abstract

Objective: A model-based conditional transfer entropy approach was exploited to quantify the information transfer in cerebrovascular (CBV) and cardiovascular (CV) systems in subjects prone to develop postural syncope. Approach: Spontaneous beat-to-beat variations of mean cerebral blood flow velocity (MCBFV) derived from a transcranial Doppler device, heart period (HP) derived from surface electrocardiogram, mean arterial pressure (MAP) and systolic arterial pressure (SAP) derived from finger plethysmographic arterial pressure device were monitored at rest in supine position (REST) and during 60° head-up tilt (TILT) in 13 individuals (age mean ± standard deviation: 28 ± 9 years, min-max range: 18-44 years, 5 males) with a history of recurrent episodes of syncope (SYNC) and in 13 age- and gender-matched controls (NonSYNC). Respiration (R) obtained from a thoracic belt was acquired as well and considered as a conditioning signal in transfer entropy assessment. Synchronous sequences of 250 consecutive MCBFV, HP, MAP, SAP and R values were utilized to estimate the information genuinely transferred from MAP to MCBFV (i.e. disambiguated from R influences) and vice versa. Analogous indexes were computed from SAP to HP and vice versa. Traditional time and frequency domain analyses were carried out as well. Main results: SYNC subjects showed an increased genuine information transfer from MAP to MCBFV during TILT, while they did not exhibit the expected rise of the genuine information transfer from SAP to HP. Significance: We conclude that SYNC individuals featured an impaired cerebral autoregulation visible during TILT and were unable to activate cardiac baroreflex to cope with the postural challenge. Traditional frequency domain markers based on transfer function modulus, phase and coherence functions were less powerful or less specific in typifying the CBV and CV controls of SYNC individuals. Conditional transfer entropy approach can identify the impairment of CBV and CV controls and provide specific clues to identify subjects prone to develop postural syncope.

Published
2017

7. Nonlinear effects of respiration on the crosstalk between cardiovascular and cerebrovascular control systems

Author

Gianluca Rossato, Beatrice De Maria, Alberto Porta, Andrea Marchi, Vlasta Bari, Giandomenico Nollo, Luca Faes, Bari, Vlasta, Marchi, Andrea, De Maria, Beatrice, Rossato, Gianluca, Nollo, Giandomenico, Faes, Luca, and Porta, Alberto

Subjects
Mean arterial pressure, medicine.medical_specialty, Supine position, General Mathematics, 0206 medical engineering, General Physics and Astronomy, 02 engineering and technology, 030204 cardiovascular system & hematology, Baroreflex, Cerebral autoregulation, Cardiovascular System, 03 medical and health sciences, Physics and Astronomy (all), 0302 clinical medicine, Engineering (all), Conditional joint symbolic analysi, Internal medicine, Respiration, medicine, Heart rate variability, Autonomic nervous system, Conditional joint symbolic analysis, Head-up tilt, Mathematics (all), business.industry, General Engineering, 020601 biomedical engineering, Cerebral blood flow, Settore ING-INF/06 - Bioingegneria Elettronica E Informatica, Cardiology, business
Abstract

Cardiovascular and cerebrovascular regulatory systems are vital control mechanisms responsible for guaranteeing homeostasis and are affected by respiration. This work proposes the investigation of cardiovascular and cerebrovascular control systems and the nonlinear influences of respiration on both regulations through joint symbolic analysis (JSA), conditioned or unconditioned on respiration. Interactions between cardiovascular and cerebrovascular regulatory systems were evaluated as well by performing correlation analysis between JSA indexes describing the two control systems. Heart period, systolic and mean arterial pressure, mean cerebral blood flow velocity and respiration were acquired on a beat-to-beat basis in 13 subjects experiencing recurrent syncope episodes (SYNC) and 13 healthy individuals (non-SYNC) in supine resting condition and during head-up tilt test at 60° (TILT). Results showed that JSA distinguished conditions and groups, whereas time domain parameters detected only the effect of TILT. Respiration affected cardiovascular and cerebrovascular regulatory systems in a nonlinear way and was able to modulate the interactions between the two control systems with different outcome in non-SYNC and SYNC groups, thus suggesting that the analysis of the impact of respiration on cardiovascular and cerebrovascular regulatory systems might improve our understanding of the mechanisms underpinning the development of postural-related syncope.

Published
2016

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