Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Time-frequency dynamics in neurally mediated syncope.

V Lepicovska1, P Novak, R Nadeau

  • 1Research Center, Hôpital du Sacré-Coeur de Montréal, Canada.

Clinical Autonomic Research : Official Journal of the Clinical Autonomic Research Society
|October 1, 1992
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Emergencies in proctology.

Rozhledy v chirurgii : mesicnik Ceskoslovenske chirurgicke spolecnosti·2025
Same author

VALID AND INFORMED CONSENT IN ORTHOPAEDIC SURGERY: A MULTICENTRE, REGIONAL SERVICE EVALUATION OF CURRENT UK PRACTICE.

Georgian medical news·2025
Same author

Algorithm of skin malignancies therapy at Department of Plastic and Aesthetic Surgery in Brno and achieved results.

Acta chirurgiae plasticae·2024
Same author

Towards optimizing the protocol for untargeted profiling of urine volatiles via gas chromatography-ion mobility spectrometry. A pilot study.

Journal of physiology and pharmacology : an official journal of the Polish Physiological Society·2024
Same author

Phagocytosis of latex beads by a human monocytic Mono Mac 6 cell line and effects of low-frequency electromagnetic field interaction.

Journal of physiology and pharmacology : an official journal of the Polish Physiological Society·2023
Same author

Intrinsic cell rheology drives junction maturation.

Nature communications·2022
Same journal

Vagus nerve stimulation and pulmonary outcomes: a scoping review of preclinical and clinical evidence.

Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2026
Same journal

Haemodynamics of (pre)syncope during carotid sinus massage: a beat-to-beat analysis of haemodynamic parameters during carotid sinus massage.

Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2026
Same journal

Orthostatic hypotension and complaints: not a clear-cut relation.

Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2026
Same journal

Co-occurrence of Chiari malformation type 1 and small fiber neuropathy in a family with a novel COL6A5 null variant.

Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2026
Same journal

Postural tachycardia during active standing: diagnostic criteria in adolescents.

Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2026
Same journal

Determinants of carotid sinus hypersensitivity in patients with suspected reflex syncope.

Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2026
See all related articles

Patients prone to vasodepressor syncope exhibit elevated parasympathetic tone at rest and during orthostasis. This sustained parasympathetic activity, coupled with inadequate sympathetic response, leads to syncope.

Area of Science:

  • Cardiovascular Physiology
  • Autonomic Nervous System Function
  • Syncope Pathophysiology

Background:

  • Recurrent unexplained syncope affects numerous individuals, impacting quality of life.
  • Understanding the autonomic nervous system's role in syncope is crucial for diagnosis and management.

Purpose of the Study:

  • To investigate beat-to-beat autonomic responses during passive orthostasis in patients with recurrent syncope.
  • To differentiate autonomic profiles between patients who experience syncope (tilt-positive) and those who do not (tilt-negative).

Main Methods:

  • Noninvasive beat-to-beat analysis of R-R intervals, systolic and diastolic pressures, and respiration during 80-degree head-up tilt.
  • Time-frequency mapping using a modified Wigner distribution for spectral estimation on a beat-to-beat basis.

Related Experiment Videos

  • Comparison of autonomic responses between 20 syncope patients (10 tilt-positive, 10 tilt-negative) and 10 healthy controls.

    • Main Results:

    • Tilt-positive patients showed gradually decreasing R-R intervals and increasing blood pressure until syncope, followed by abrupt hypotension and bradycardia.
    • Tilt-positive patients exhibited higher R-R interval fluctuations at rest and during tilt compared to tilt-negative and control groups.
    • Elevated parasympathetic tone at rest, persisting during orthostasis, was identified in tilt-positive patients, indicating proneness to vasodepressor syncope.

    Conclusions:

    • Sustained elevated parasympathetic tone at rest and during orthostasis identifies patients susceptible to vasodepressor syncope.
    • Inadequate and unsustained sympathetic counteraction contributes to hypotension, cardioinhibition, and loss of consciousness during syncope.
    • Time-frequency mapping is a valuable tool for assessing beat-to-beat autonomic regulation in syncope patients.