Diagnosis and Treatment of Neurally Mediated Syncope

2002 ◽  
Vol 8 (3) ◽  
pp. 175-185 ◽  
Author(s):  
Horacio Kaufmann ◽  
Kirsty Bhattacharya
Keyword(s):  
Diagnosis And Treatment ◽  
Neurally Mediated Syncope

Diurnal variation in time to presyncope and associated circulatory changes during a controlled orthostatic challenge

2010 ◽  
Vol 299 (1) ◽  
pp. R55-R61 ◽  
Author(s):  
N. C. S. Lewis ◽  
G. Atkinson ◽  
S. J. E. Lucas ◽  
E. J. M. Grant ◽  
H. Jones ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Diurnal Variation ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Cerebral Blood Flow Velocity ◽  
Orthostatic Challenge ◽  
Arterial Blood ◽  
Neurally Mediated Syncope

Epidemiological data indicate that the risk of neurally mediated syncope is substantially higher in the morning. Syncope is precipitated by cerebral hypoperfusion, yet no chronobiological experiment has been undertaken to examine whether the major circulatory factors, which influence perfusion, show diurnal variation during a controlled orthostatic challenge. Therefore, we examined the diurnal variation in orthostatic tolerance and circulatory function measured at baseline and at presyncope. In a repeated-measures experiment, conducted at 0600 and 1600, 17 normotensive volunteers, aged 26 ± 4 yr (mean ± SD), rested supine at baseline and then underwent a 60° head-up tilt with 5-min incremental stages of lower body negative pressure until standardized symptoms of presyncope were apparent. Pretest hydration status was similar at both times of day. Continuous beat-to-beat measurements of cerebral blood flow velocity, blood pressure, heart rate, stroke volume, cardiac output, and end-tidal Pco2 were obtained. At baseline, mean cerebral blood flow velocity was 9 ± 2 cm/s (15%) lower in the morning than the afternoon ( P < 0.0001). The mean time to presyncope was shorter in the morning than in the afternoon (27.2 ± 10.5 min vs. 33.1 ± 7.9 min; 95% CI: 0.4 to 11.4 min, P = 0.01). All measurements made at presyncope did not show diurnal variation ( P > 0.05), but the changes over time (from baseline to presyncope time) in arterial blood pressure, estimated peripheral vascular resistance, and α-index baroreflex sensitivity were greater during the morning tests ( P < 0.05). These data indicate that tolerance to an incremental orthostatic challenge is markedly reduced in the morning due to diurnal variations in the time-based decline in blood pressure and the initial cerebral blood flow velocity “reserve” rather than the circulatory status at eventual presyncope. Such information may be used to help identify individuals who are particularly prone to orthostatic intolerance in the morning.

Reflex Syncope (Neurally Mediated Syncope)

Syncope ◽  
2010 ◽  
pp. 153-177 ◽  
Author(s):  
Michele Brignole ◽  
David G. Benditt
Keyword(s):  
Reflex Syncope ◽  
Neurally Mediated Syncope

Effects of the tilt training on neurally mediated syncope—a study on the autonomic nervous activities in normal subjects

2011 ◽  
Vol 44 (2) ◽  
pp. e48-e49
Author(s):  
Hideki Kumagai ◽  
Machiko Yamamoto ◽  
Kana Yamada ◽  
Kentarou Kaneko ◽  
Yu Ogata
Keyword(s):  
Normal Subjects ◽  
Autonomic Nervous ◽  
Neurally Mediated Syncope

scholarly journals Adenosine and Clinical Forms of Neurally-Mediated Syncope

2015 ◽  
Vol 66 (2) ◽  
pp. 204-205 ◽  
Author(s):  
Regis Guieu ◽  
Jean-Claude Deharo ◽  
Jean Ruf ◽  
Giovanna Mottola ◽  
Nathalie Kipson ◽  
...  
Keyword(s):  
Clinical Forms ◽  
Neurally Mediated Syncope

scholarly journals Assessment of 123I-MIBG Scintigraphy as a Diagnostic Tool for Neurally Mediated Syncope

2011 ◽  
Vol 27 (Supplement) ◽  
pp. PE4_061
Author(s):  
Shunji Fukunaga ◽  
Yoshifumi Okano ◽  
Hitomi Yuzawa ◽  
Hideyuki Sato ◽  
Tadashi Fujino ◽  
...  
Keyword(s):  
Diagnostic Tool ◽  
Mibg Scintigraphy ◽  
Neurally Mediated Syncope
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