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Acoplamiento dinámico global de activación y repolarización en el ventrículo humano
Arthur M Yue1, Tim R Betts, Paul R Roberts
1Wessex Cardiac Center, Southampton General Hospital, Southampton SO16 6YD, UK.
Circulation
|October 26, 2005
Resumen
El mapeo sin contacto puede evaluar la dinámica de repolarización ventricular. Este estudio muestra un acoplamiento inverso entre activación y repolarización, preservando potencialmente la estabilidad eléctrica en los ventrículos sanos.
Área de la Ciencia:
- Electrofisiología cardiovascular electrofisiología cardiovascular.
- Mapeo cardíaco del corazón.
- La Dinámica Ventricular es una Dinámica Ventricular.
Sus antecedentes:
- Comprender los cambios de repolarización ventricular es crucial para identificar los mecanismos aritmogénicos.
- El mapeo sin contacto ofrece un método potencial para estudiar el acoplamiento de activación-repolarización global en el ventrículo humano.
Objetivo del estudio:
- Investigar la viabilidad de utilizar el mapeo sin contacto para analizar el acoplamiento global de activación-repolarización en el ventrículo humano.
- Examinar este acoplamiento durante diversas condiciones electrofisiológicas, incluyendo el estado estacionario y la estimulación prematura.
Principales métodos:
- Los intervalos de activación-recuperación (ARI) se midieron en 32 sitios por ventrículo utilizando el sistema Ensite en 13 pacientes sin enfermedad cardíaca estructural.
- El método fue validado con registros de potenciales de acción monofásicos y electrogramas de contacto unipolares.
- La distribución global de ondas T se visualizó en un modelo ventricular 3D.
Principales resultados:
- Se encontró una correlación inversa significativa entre los tiempos de activación y las IRA durante el ritmo sinusal, la ectopia ventricular y la estimulación prematura (r = 0,72, P < 0,001).
- Los estímulos prematuros en intervalos cortos de acoplamiento alteraron la pendiente de regresión pero preservaron el patrón de repolarización global.
- La medición del ARI del sistema Ensite demostró un acoplamiento significativo, a diferencia del método Wyatt (r = 0,34).
Conclusiones:
- El mapeo global y dinámico de repolarización del ventrículo humano es factible utilizando el mapeo sin contacto.
- Un acoplamiento inverso entre la activación y la repolarización durante el estado estacionario y la estimulación prematura puede contribuir a mantener la estabilidad eléctrica en los ventrículos normales.
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