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Remodelación eléctrica en la fibrilación auricular. Curso de tiempo y mecanismos
A Goette1, C Honeycutt, J J Langberg
1Carlyle Fraser Heart Center, Atlanta, Ga, USA.
Circulation
|December 1, 1996
Resumen
La remodelación eléctrica auricular, un factor clave en la fibrilación auricular, se desarrolla rápidamente y es impulsada por la sobrecarga de calcio intracelular. Este proceso acorta los períodos refractarios, contribuyendo a la progresión de la enfermedad.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- La remodelación cardíaca remodelación cardíaca.
Sus antecedentes:
- La fibrilación auricular (FA) es una condición progresiva.
- Los ritmos auriculares rápidos inducen cambios electrofisiológicos, conocidos como remodelación eléctrica, que acortan los períodos refractarios.
- La comprensión de los mecanismos de remodelación eléctrica es crucial para la gestión de AF.
Objetivo del estudio:
- Para investigar el curso temporal de la remodelación eléctrica auricular.
- Para aclarar los mecanismos subyacentes de la remodelación eléctrica.
Principales métodos:
- Los perros anestesiados se sometieron a 7 horas de estimulación auricular a 800 bpm.
- Se midieron los períodos refractarios efectivos y absolutos (ARP y ERP).
- Se analizaron muestras de biopsia endocárdica transvenosa utilizando microscopía electrónica.
Principales resultados:
- El ritmo atrial rápido acortó significativamente la ARP y la ERP (> 10%), lo que indica una remodelación eléctrica.
- La remodelación eléctrica se produjo rápidamente, con más de la mitad desarrollándose en 30 minutos.
- El verapamil bloqueó la remodelación, mientras que la hipercalcemia la acentuó, lo que sugiere un papel para el calcio.
Conclusiones:
- La remodelación eléctrica auricular es un fenómeno rápido, progresivo y potencialmente persistente.
- El tono autónomo, el estiramiento auricular y el agotamiento de la energía no son los principales impulsores.
- La sobrecarga de calcio intracelular inducida por la velocidad es el probable mediador de la remodelación eléctrica auricular.
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