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Predisposición al síncope vasovagal en sujetos con fobia a la sangre/lesiones
V Accurso1, M Winnicki, A S Shamsuzzaman
1Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA.
Circulation
|August 22, 2001
Resumen
Las personas con fobia a la sangre / lesión a menudo se desmayan debido a la desregulación autónoma. Este estudio muestra que están predispuestos a la síncope vasovagal durante la inclinación de la cabeza hacia arriba, incluso sin un desencadenante.
Área de la Ciencia:
- Fisiología Fisiología Fisiología.
- El sistema nervioso autónomo.
- Psicofisiología Psicofisiología.
Sus antecedentes:
- La fobia a la sangre / lesión se asocia con frecuencia con síncope o presíncope.
- Se supone que la desregulación autónoma es un factor predisponente para el síncope vasovagal en estos individuos.
Objetivo del estudio:
- Para probar la hipótesis de que los sujetos con fobia a la sangre / lesión tienen desregulación autónoma constitucional.
- Para investigar la predisposición a la síncope vasovagal durante la inclinación de la cabeza hacia arriba en esta población.
Principales métodos:
- Se estudiaron 11 sujetos con síncope inducida por fobia a la sangre / lesión y 11 controles sanos.
- La presión arterial y la frecuencia cardíaca se monitorearon durante una línea de base de 15 minutos y una inclinación de la cabeza hacia arriba de 45 minutos a 70 grados.
Principales resultados:
- El 82% de los sujetos con fobia a la sangre experimentaron presíncope o síncope durante la inclinación, en comparación con el 9% de los controles (P = 0,001).
- Los sujetos con fobia a la sangre mostraron respuestas vasovágicas, con disminuciones significativas en la presión arterial sistólica (21 mmHg) y la frecuencia cardíaca (22 bpm) durante la inclinación.
- Los sujetos de control mostraron presión arterial y frecuencia cardíaca estables durante la inclinación de la cabeza hacia arriba.
Conclusiones:
- Las personas con fobia a la sangre / lesión exhiben una desregulación autónoma subyacente.
- Esta desregulación los predispone a una síncope mediada neuralmente, independiente de los estímulos fóbicos específicos.
- Los eventos sincópicos repetidos pueden contribuir al desarrollo o la exacerbación de la fobia a la sangre / lesión.
Palabras clave:
No programático No programático.
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