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El antagonista de la angiotensina II previene la remodelación eléctrica en la fibrilación auricular
H Nakashima1, K Kumagai, H Urata
1Second Department of Internal Medicine, School of Medicine, Fukuoka University, Fukuoka, Japan. kxk@fukuoka-u.ac.jp
Circulation
|June 7, 2000
Resumen
El bloqueo de la angiotensina II (Ang II) previene la remodelación eléctrica auricular al inhibir el acortamiento del período refractario efectivo auricular. Esto sugiere que el bloqueo Ang II podría ser una estrategia terapéutica para la fibrilación auricular.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Electrofisiología y electrofisiología.
Sus antecedentes:
- El bloqueo de la formación de angiotensina II (Ang II) ofrece protección cardiovascular.
- El papel específico de Ang II en la remodelación eléctrica auricular sigue sin estar claro.
Objetivo del estudio:
- Para investigar el impacto de candesartan y captopril en la remodelación eléctrica auricular.
- Para determinar si Ang II influye en el período refractario efectivo auricular (AERP) durante el ritmo rápido.
Principales métodos:
- Los perros se sometieron a un ritmo atrial rápido (800 bpm durante 180 minutos).
- Los grupos recibieron solución salina, candesartan, captopril o una infusión de Ang II.
- Se midió el período refractario auricular efectivo (AERP) antes y después del ritmo.
Principales resultados:
- Los grupos Saline y Ang II mostraron un acortamiento significativo de la AERP.
- El candesartán y el captopril inhibieron completamente el acortamiento de la AERP.
- La tasa de adaptación de AERP se conservó con candesartan y captopril.
Conclusiones:
- La inhibición endógena de Ang II previene el acortamiento de la AERP durante el ritmo atrial rápido.
- Ang II está implicado en los mecanismos de remodelación eléctrica auricular.
- El bloqueo de Ang II puede ofrecer beneficios terapéuticos para la fibrilación auricular humana.
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