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La isquemia auricular promueve la fibrilación auricular en perros
Hani Sinno1, Katayoun Derakhchan, Danielle Libersan
1Department of Medicine, Montreal Heart Institute and University of Montreal, Montreal, Quebec, Canada.
Circulation
|April 2, 2003
Resumen
La isquemia auricular, inducida experimentalmente, prolonga significativamente la duración de la fibrilación auricular (FA) al ralentizar la conducción eléctrica. Esto sugiere que la isquemia auricular es un factor clave en el mantenimiento de la FA, especialmente en pacientes con enfermedad arterial coronaria.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- Enfermedad Isquémica del Corazón.
Sus antecedentes:
- La enfermedad de las arterias coronarias es un factor de riesgo conocido para la fibrilación auricular (FA).
- Los mecanismos subyacentes que vinculan la enfermedad de la arteria coronaria a la FA no se comprenden completamente.
- Este estudio investiga el papel de la isquemia auricular en el desarrollo de la FA.
Objetivo del estudio:
- Evaluar la hipótesis de que la isquemia auricular puede crear un sustrato para el mantenimiento de la FA.
- Investigar el impacto de la isquemia auricular inducida experimentalmente en la duración de la FA y las propiedades electrofisiológicas.
Principales métodos:
- La isquemia auricular fue inducida en perros por la oclusión de una arteria auricular no coronaria.
- La fibrilación auricular fue inducida usando ritmo de ráfaga.
- Se midieron parámetros electrofisiológicos, incluida la velocidad de conducción y la refractividad.
- Se realizó un mapeo de alta densidad y un examen histológico.
Principales resultados:
- La isquemia auricular aumentó significativamente la duración de la FA (de 57+/-32s a más de 800s, P<0,001).
- La FA prolongada (>20 min) se produjo en el 38-44% de los perros isquémicos frente al 0% de los controles (P<0,01).
- La isquemia causó una desaceleración sustancial de la conducción auricular (por ejemplo, de 8+/-1ms a 27+/-5ms a 200ms de duración del ciclo, P<0,001) y necrosis.
Conclusiones:
- La isquemia auricular experimental crea un sustrato que promueve el mantenimiento de la FA, probablemente a través de la desaceleración de la conducción localizada y la reentrada.
- La isquemia auricular puede ser un factor contribuyente significativo a la FA en el contexto de la enfermedad arterial coronaria.
- Estos hallazgos destacan un objetivo terapéutico potencial para el manejo de la FA en pacientes con enfermedad cardíaca isquémica.
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