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Las respuestas de His-Purkinje y los períodos refractarios durante la extrastimulación auricular en niños con
Circulation
|June 1, 1981
Resumen
Los pacientes pediátricos con defecto cardíaco muestran respuestas anormales del sistema de His-Purkinje, incluyendo potenciales divididos de His y intervalos prolongados de His a ventricular, durante la extrastimulación auricular. Estos hallazgos sugieren características electrofisiológicas funcionales en el sistema de conducción cardíaca pediátrica.
Área de la Ciencia:
- Electrofisiología y electrofisiología.
- Cardiología Pediátrica Cardiología pediátrica.
- El sistema de conducción cardíaca es un sistema de conducción cardíaca.
Sus antecedentes:
- Los defectos cardíacos congénitos pueden afectar la conducción cardíaca.
- Comprender el sistema pediátrico His-Purkinje es crucial para el manejo de las arritmias.
Objetivo del estudio:
- Para investigar las características electrofisiológicas del sistema His-Purkinje en pacientes pediátricos con defectos cardíacos.
- Para identificar las respuestas de His-Purkinje durante la extrastimulación auricular en niños preoperativos y postoperatorios.
Principales métodos:
- La extrastimulación auricular se realizó en 78 pacientes pediátricos con defectos cardíacos.
- Se analizaron sus potenciales, sus intervalos His-to-ventricular (H2V2) y su refractividad.
- Los pacientes fueron evaluados tanto preoperatorio como postoperatorio.
Principales resultados:
- Las respuestas de His-Purkinje se identificaron en el 40% de los pacientes.
- Los potenciales de Split His se observaron en 14 pacientes.
- Se observaron intervalos prolongados de H2V2 y bloqueo distal a la desviación del haz de His en un subconjunto significativo de pacientes.
Conclusiones:
- Las respuestas anormales del sistema His-Purkinje, incluidos los potenciales divididos de His y los intervalos prolongados de H2V2, están presentes en pacientes pediátricos con defectos cardíacos.
- Estos hallazgos electrofisiológicos parecen ser características funcionales del sistema de conducción cardíaca pediátrica.
- Las respuestas observadas se produjeron tanto en pacientes preoperatorios como en pacientes postoperatorios, lo que indica su relevancia en diferentes etapas quirúrgicas.
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