Multistructure index characterization of heart rate and systolic blood pressure reveals precursory signs of syncope.
Recurrent syncope - abrupt loss of consciousness - can have a serious impact on patients' quality of life, comparable with chronic illnesses. Vasovagal syncope (VVS) is a specific reflex syncope, in which an inappropriate reaction of the autonomic nervous system (ANS) plays a key role in the pathophysiology. In syncope diagnosis, an ideal diagnostic method should positively identify vasovagal sensitive patients, without the need to perform a specialised head-up tilt table (HUTT) test. We apply a novel methodology of multistructure index (MI) statistics for seamlessly evaluating the size spectrum of the asymmetry properties of magnitudes of neural reflexes responsible for maintaining the homeostatic dynamics of autonomic control. Simultaneous evaluation using the MI of the effects on heart rate and blood pressure involved in achieving homeostasis of contrasting properties of the dynamics of slow and fast neural regulation reveals a clear distinction between vasovagal patients and healthy subjects, who are/are not susceptible to spontaneous fainting. Remarkably, a healthy cardiovascular response to the HUTT test is indeed evident prior to the test, making the MI a robust novel indicator, clearly distinguishing the cardiovascular autonomic regulation of healthy people from that of vasovagal patients without the need to perform an actual HUTT test.
Institute of Theoretical Physics and Astrophysics, The University of Gdańsk, Wita Stwosza 57, 80-308, Gdańsk, Poland.
Danuta
D
Makowiec
Department of Hypertension and Diabetology, Medical University of Gdańsk, M. Sklodowskiej-Curie 3a, 80-210, Gdańsk, Poland.
Beata
B
Graff
RIKEN Brain Science Institute, 2-1 Hirosawa, Wako-shi, 351-0198, Japan. z.r.struzik@p.u-tokyo.ac.jp.|Graduate School of Education, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. z.r.struzik@p.u-tokyo.ac.jp.
Zbigniew R
0000-0002-1352-8897
ZR
Struzik
D000328:Adult; D001341:Autonomic Nervous System / Q000502:physiology*; D001794:Blood Pressure; D003627:Data Interpretation, Statistical; D005260:Female; D006339:Heart Rate; D000070276:Heart Rate Determination / Q000379:methods*; D006801:Humans; D008297:Male; D019462:Syncope, Vasovagal / Q000175:diagnosis* / Q000503:physiopathology*; D018667:Tilt-Table Test; D055815:Young Adult