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Efectos del bloqueo autónomo selectivo en las ondas T alternas en humanos
Eric J Rashba1, Michael Cooklin, Karen MacMurdy
1Division of Cardiology, Department of Medicine, University of Maryland at Baltimore, 21201, USA. erashba@medicine.umaryland.edu
Circulation
|February 21, 2002
Resumen
La actividad del sistema nervioso simpático impacta significativamente las mediciones de las ondas T alternas (TWA) en pacientes cardíacos de alto riesgo. El uso de beta-bloqueantes puede reducir el TWA, lo que potencialmente reduce el riesgo de muerte súbita cardíaca.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- El sistema nervioso autónomo.
Sus antecedentes:
- Los alternantes de onda T (TWA) son un marcador no invasivo clave para la vulnerabilidad a la arritmia ventricular.
- Los pacientes con enfermedad de las arterias coronarias (CAD) tienen un alto riesgo de sufrir arritmias.
- El papel del sistema nervioso autónomo (SNA) en TWA en estos pacientes no se entiende completamente.
Objetivo del estudio:
- Para investigar la influencia del sistema nervioso autónomo en las mediciones de TWA.
- Para evaluar la TWA en pacientes con enfermedad arterial coronaria de alto riesgo.
- Para determinar si el bloqueo simpático o parasimpático afecta a la TWA.
Principales métodos:
- Se estudiaron sesenta pacientes con EAC con disfunción ventricular izquierda y taquicardia ventricular inducible.
- La TWA se midió al inicio y después del bloqueo simpático (esmolol), el bloqueo parasimpático (atropina) o ninguna intervención (controles).
- El acelerador auricular se utilizó para estandarizar la frecuencia cardíaca durante las mediciones de TWA.
Principales resultados:
- El bloqueo parasimpático (atropina) y las condiciones de control no alteraron la prevalencia de TWA.
- El bloqueo simpático con esmolol redujo significativamente la amplitud de la TWA (P<0.001).
- El Esmolol redujo las pruebas positivas de TWA en un 50% (70% a 35%, P<0,05).
Conclusiones:
- La modulación del sistema nervioso autónomo, particularmente la actividad simpática, afecta el TWA.
- TWA puede ser una herramienta útil para la estratificación de riesgo de los pacientes con CAD.
- Los betabloqueantes podrían reducir el riesgo de muerte súbita cardíaca al afectar favorablemente la TWA en pacientes con CAD.
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