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Efectos electrofisiológicos de la adenosina en pacientes con taquicardia supraventricular
K A Glatter1, J Cheng, P Dorostkar
1Cardiovascular Research Institute and Section of Cardiac Electrophysiology, University of California-San Francisco, CA, USA.
Circulation
|March 2, 1999
Resumen
La Adenosina es una sustancia
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
Sus antecedentes:
- Los efectos electrofisiológicos (EP) de la adenosina se correlacionaron con los mecanismos de taquicardia en pacientes con taquicardias supraventriculares (TVS).
Objetivo del estudio:
- Para evaluar la utilidad de la adenosina en la diferenciación de los mecanismos SVT.
- Para identificar respuestas EP específicas a la adenosina que se correlacionan con distintos tipos de taquicardia.
Principales métodos:
- La adenosina se administró a 229 pacientes con varios SVTs durante el estudio EP.
- Cambios observados y registrados en el ritmo cardíaco, los intervalos (atrial, AV, VA) y la terminación de la taquicardia.
- Respuestas comparadas a la adenosina en diferentes subtipos de SVT: AVRT, AVNRT, PJRT, AT y IST.
Principales resultados:
- La adenosina demostró tasas similares de terminación de la taquicardia en el nodo AV para AVRT y AVNRT.
- Se observó un aumento de los intervalos ventriculoatrial (VA) en la TAV, pero no en la TAVN típica.
- El bloqueo AV se observó principalmente en pacientes con AT e IST.
- La incidencia de fibrilación auricular fue más alta con AVRT, PJRT y AT en comparación con AVNRT.
- Los pacientes con IST mostraron un aumento de la longitud del ciclo auricular sin cambios significativos en la secuencia de activación.
Conclusiones:
- La respuesta EP de la adenosina tiene un valor limitado para identificar la ubicación de AT o mecanismos específicos de SVT.
- El bloqueo AV y la duración acortada del ciclo auricular antes de la supresión sugieren AT.
- La fibrilación auricular después de la adenosina es más frecuente en AVRT, PJRT o AT.
- Los pacientes con TSI exhiben una duración prolongada del ciclo con una activación auricular estable después de la adenosina.
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