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El gadolinio disminuye la vulnerabilidad inducida por el estiramiento a la fibrilación auricular
F Bode1, A Katchman, R L Woosley
1Department of Pharmacology, Georgetown University, Veterans Affairs Medical Center, Washington, DC 20422, USA.
Circulation
|May 10, 2000
Resumen
El estiramiento auricular aumenta el riesgo de fibrilación auricular (FA). El bloqueo de los canales activados por estiramiento (SAC) con gadolinio (Gd3 +) reduce significativamente esta vulnerabilidad, lo que sugiere una nueva estrategia antiarrítmica para la FA.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- Farmacología Farmacología.
Sus antecedentes:
- La fibrilación auricular (FA) está relacionada con el agrandamiento auricular por sobrecarga de presión/volumen.
- Los canales activados por estiramiento (SAC) en las células del miocardio pueden contribuir a la FA en las aurículas dilatadas.
Objetivo del estudio:
- Para investigar el efecto del bloqueador SAC gadolinio (Gd3 +) en la propensión a la FA durante el estiramiento auricular en corazones de conejo aislados.
Principales métodos:
- Se utilizaron corazones de conejo aislados con perfusión de Langendorff.
- Se aumentó la presión auricular y se evaluó la vulnerabilidad de la FA a través del ritmo de ráfaga.
- El gadolinio (Gd3+) fue administrado en dosis crecientes (12,5, 25, 50 μmol/L).
Principales resultados:
- La inducción de la FA requirió una presión auricular significativamente más alta después de la administración de Gd3+ (19,0±0,5 cm de H2O con 50 μmol/L de Gd3+ frente a 8,8±0,2 cm de H2O al inicio).
- Gd3+ dependiendo de la dosis, redujo la vulnerabilidad de la FA y evitó las ejecuciones espontáneas de la FA.
- Gd3+ no afectó significativamente el período refractario atrial efectivo.
Conclusiones:
- El estiramiento auricular agudo aumenta la vulnerabilidad de la FA.
- El gadolinio (Gd3+) reduce efectivamente la vulnerabilidad de la FA inducida por el estiramiento de una manera dependiente de la dosis.
- El bloqueo de las SAC puede ofrecer un nuevo enfoque antiarrítmico para la FA asociada con presión o volumen auricular elevado.
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