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Efecto de la estimulación adrenérgica en la restitución de la duración del potencial de acción en humanos
Peter Taggart1, Peter Sutton, Zaid Chalabi
1The Hatter Institute, Department of Cardiology, University College London HospitalsLondon, WC1E 6DB. peter.taggart@uclh.org.
Circulation
|January 23, 2003
Resumen
Los agonistas adrenérgicos como la isoprenalina y la adrenalina aumentan la pendiente de restitución de la duración del potencial de acción (APD) en los seres humanos. Este hallazgo puede explicar cómo la actividad simpática promueve la fibrilación ventricular.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Electrofisiología y electrofisiología.
Sus antecedentes:
- La actividad simpática influye en las arritmias ventriculares.
- La restitución de la duración del potencial de acción (APD) es clave para la estabilidad eléctrica del miocardio.
- Las pendientes de restitución de APD más pronunciadas pueden desencadenar ruptura de onda y fibrilación ventricular.
Objetivo del estudio:
- Investigar el efecto de la estimulación adrenérgica en la restitución de la DPA en humanos.
- Para determinar si los agonistas adrenérgicos alteran la pendiente de la restitución de la APD.
Principales métodos:
- Potenciales de acción monofásicos registrados desde el tabique ventricular derecho en 18 pacientes.
- Las curvas de restitución de APD se construyen a longitudes de ciclo de 600, 500 y 400 ms.
- Infusión de isoprenalina o adrenalina durante las mediciones.
Principales resultados:
- Los agonistas adrenérgicos (isoprenalina, adrenalina) aumentaron significativamente la pendiente de la pendiente máxima de la restitución de la APD.
- El efecto fue más pronunciado en ciclos básicos más cortos.
- Las condiciones de control mostraron pendientes más pronunciadas en longitudes de ciclo básico más largas.
Conclusiones:
- La isoprenalina y la adrenalina mejoran la pendiente de la pendiente de restitución de la APD en los seres humanos.
- Este efecto adrenérgico en la restitución de la APD puede contribuir a la facilitación de la fibrilación ventricular.
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