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Procainamida y conducción nodal atrioventricular retrógrada en el hombre
Circulation
|February 1, 1982
Resumen
La procainamida intravenosa (PA) deprime la conducción nodal atrioventricular (AV) retrógrada en la mayoría de los pacientes. Este efecto no indica la presencia de vías de derivación nodal AV, al contrario de las sugerencias anteriores.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
Sus antecedentes:
- Estudios anteriores sugirieron que la procainamida (PA) podría ayudar a identificar las vías de derivación nodal atrioventricular (AV) por su efecto en la conducción retrógrada.
- Los efectos electrofisiológicos precisos de la PA en la conducción nodal AV normal necesitaban una mayor aclaración.
Objetivo del estudio:
- Para investigar los efectos electrofisiológicos de la procainamida intravenosa (PA) en la conducción nodal atrioventricular (AV) retrógrada en pacientes sin taquicardia reentrante conocida o vías accesorias.
Principales métodos:
- Estudio electrofisiológico en 13 pacientes sin taquicardia reentrante nodal AV o vías accesorias.
- La administración intravenosa de procainamida (10 mg/kg) también es posible.
- Registro de la conducción ventriculoatrial (VA) utilizando electrogramas intracardiacos, ritmo ventricular incremental y extrastimulación ventricular antes y después de la administración de PA.
Principales resultados:
- La procainamida (PA) abolió la conducción nodal AV retrógrada en 5/13 pacientes y prolongó la duración del ciclo para el bloqueo AV en 7/13 pacientes.
- La PA invariablemente prolongaba el intervalo de VA en longitudes de ciclo de ritmo comparables.
- PA eliminado o prolongado retrógrado H2A2 intervalos durante la estimulación ventricular prematura en la mayoría de los pacientes.
Conclusiones:
- La procainamida intravenosa (PA) suprime uniformemente la conducción nodal AV retrógrada en el corazón humano intacto.
- El efecto depresor observado de la AP en la conducción nodal AV retrógrada no es indicativo de la presencia de vías de derivación nodal AV.
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