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Updated: Jul 13, 2026
08:43
Application of Granger Causality Analysis of the Directed Functional Connection in Alzheimer's Disease and Mild Cognitive Impairment
Published on: August 7, 2017
Enlace en las vías accesorias. Pérdida funcional de la preexcitación antegrada
M D Gonzalez1, A J Greenspon, G A Kidwell
1Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA.
Circulation
|April 1, 1991
Resumen
La activación retrógrada oculta, o vinculación, en el síndrome de Wolff-Parkinson-White implica un bloqueo bidireccional en las vías accesorias. Este fenómeno depende de la refractividad y retrogrado retraso de activación, y puede ser interrumpido por ventricular extrastimuli.
Área de la Ciencia:
- Electrofisiología y electrofisiología.
- Cardiología Cardiología.
Sus antecedentes:
- La activación retrógrada oculta es un mecanismo propuesto para el bloqueo de conducción antegrado.
- Este estudio investigó la vinculación en 10 pacientes con el síndrome de Wolff-Parkinson-White.
Objetivo del estudio:
- Para probar la hipótesis de que la activación retrógrada oculta causa bloqueo de conducción antegrado.
- Definir las condiciones y características de las conexiones de las vías accesorias.
Principales métodos:
- Los pacientes con síndrome de Wolff-Parkinson-White se sometieron a una pausa auricular excesiva para inducir un bloqueo persistente antes de la degradación.
- Un protocolo de ritmo auricular definió una "ventana de enlace" de longitudes de ciclo.
- Se utilizaron estímulos ventriculares prematuros para interrumpir el enlace.
Principales resultados:
- Se identificó una ventana de enlace (70-290 msec), donde la conducción de la vía accesoria dependía del estado anterior.
- La ventana de enlace se aproximó retrógrado retraso de activación.
- La refractividad de la vía accesoria antegrada excedió la de la vía atrioventricular y podría ser interrumpida por extrastimules ventriculares.
Conclusiones:
- La vinculación de vías accesorias está asociada con el bloqueo bidireccional.
- La iniciación y la estabilidad del enlace dependen de la relación entre la refractividad antegrada y el retraso de activación retrógrada.
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