Search results for "postural syncope"

showing 3 items of 3 documents

Cerebrovascular and cardiovascular variability interactions investigated through conditional joint transfer entropy in subjects prone to postural syn…

2017

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 r…

AdultMalemedicine.medical_specialtyMean arterial pressureSupine positioncerebral autoregulationAdolescentPhysiologyUltrasonography Doppler TranscranialEntropyBiomedical EngineeringBiophysics030204 cardiovascular system & hematologyBaroreflexCerebral autoregulationSyncope03 medical and health sciencesElectrocardiographyYoung Adult0302 clinical medicinehead-up tiltHeart RatePhysiology (medical)Internal medicineinformation transfermedicineHeart rate variabilityHumansbaroreflexArterial Pressurebusiness.industryautonomic nervous systemheart rate variabilitySignal Processing Computer-AssistedTranscranial DopplerPlethysmographyBlood pressureBiophysicCerebral blood flowpostural syncopeAnesthesiaCerebrovascular CirculationSettore ING-INF/06 - Bioingegneria Elettronica E InformaticaCardiologyFemaleDisease Susceptibilitybusiness030217 neurology & neurosurgeryHumanPhysiological measurement
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Strength and Latency of the HP-SAP Closed Loop Variability Interactions in Subjects Prone to Develop Postural Syncope

2019

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 durin…

AdultMalemedicine.medical_specialtySupine positiongenetic structuresBlood Pressure030204 cardiovascular system & hematologyBaroreflexSyncope03 medical and health sciencesYoung Adult0302 clinical medicineHeart RateInternal medicineHeart ratemedicineHumansComputer SimulationLatency (engineering)business.industryFeed forwardPostural syncopeHeartBaroreflexAdult Blood Pressure Computer Simulation Heart Rate Humans Male Syncope Young Adult Baroreflex HeartBlood pressureCardiologybusinessClosed loop030217 neurology & neurosurgeryAnnual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
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Investigating cardiovascular and cerebrovascular variability in postural syncope by means of extended Granger causality

2014

The patterns of Granger causality (GC) between heart period (HP), mean arterial pressure (AP) and cerebral blood flow velocity (FV) were investigated in ten subjects with postural related syncope (PRS). The classic GC measure based on vector autoregressive (VAR) modeling was compared with a novel extended GC (eGC) measure derived from VAR models incorporating instantaneous causal effects among the series. The analysis was performed in the supine and in the upright position during early (ET) and late (LT, close to presyncope) epochs of head-up tilt. Moving from ET to LT, both GC and eGC decreased from AP to HP, and increased from AP to FV, reflecting baroreflex impairment and loss of cerebra…

medicine.medical_specialtyPhysical medicine and rehabilitationGranger causalityAnesthesiaSettore ING-INF/06 - Bioingegneria Elettronica E InformaticamedicinePostural syncopeBiomedical EngineeringPsychology
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