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Conducción nodal atrioventricular durante la fibrilación auricular: el papel de la modificación de la entrada
S Garrigue1, K A Mowrey, G Fahy
1Department of Cardiology, the Cleveland Clinic Foundation, Cleveland, Ohio, USA.
Circulation
|May 5, 1999
Resumen
La ablación posteroseptal para la fibrilación auricular (FA) no elimina la vía lenta del nódulo AV. La desaceleración de la velocidad ventricular se produce debido a la reducción del bombardeo nodal AV, no a la eliminación lenta de la vía.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- Cirugía cardíaca Cirugía cardíaca.
Sus antecedentes:
- La ablación posteroseptal se dirige al nodo atrioventricular (AVN) para controlar la frecuencia ventricular durante la fibrilación auricular (FA).
- El presunto mecanismo implica la eliminación de la vía lenta de la AVN.
- Las tasas de éxito impredecibles sugieren que un mecanismo alternativo puede estar en juego.
Objetivo del estudio:
- Para investigar el efecto de la ablación posteroseptale en la vía lenta de la NAV durante la fibrilación auricular simulada.
- Para determinar si la desaceleración de la velocidad ventricular se debe a la eliminación lenta de la vía o a la reducción del bombardeo nodal AV.
Principales métodos:
- Utilizó preparaciones de AVN auricular del corazón de conejo.
- El enfriamiento aplicado a los enfoques AVN para evaluar los efectos de la vía.
- AF simulado antes y después de los cortes quirúrgicos posterosépticos, monitoreando los intervalos His-His (H-H) y las tasas de bombardeo nodal AV.
Principales resultados:
- El enfriamiento posterior mostró efectos no específicos en las vías AVN.
- Los cortes posteroseptales durante la AF prolongaron los intervalos H-H y ralentizaron el bombardeo nodal AV sin afectar el H-H mínimo, lo que indica una vía lenta intacta.
- El origen y los cortes anteriores de AF no alteraron los intervalos H-H o las tasas de bombardeo.
Conclusiones:
- La ablación posteroseptal no elimina la vía lenta de la NAV.
- La desaceleración de la frecuencia ventricular durante la AF después de la ablación posteroséptica se logra mediante la reducción del bombardeo nódulo AV, potencialmente a través de un bloqueo intraatrial posteroanterior.
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