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Efecto de la sincronización de ondas P durante la taquicardia supraventricular en la respuesta neuronal hemodinámica
M H Hamdan1, J D Zagrodzky, R L Page
1University of Texas Southwestern Medical Center and Dallas Veterans Affairs Medical Center, Dallas, TX 75216, USA. Hamdan@ryburn.swmed.edu44195
Circulation
|January 4, 2001
Resumen
La taquicardia supraventricular (SVT, por sus siglas en inglés) afecta a la hemodinámica. La taquicardia de RP larga (RP>PR) mantiene mejor la estabilidad hemodinámica al reducir la actividad del nervio simpático (SNA) en comparación con la taquicardia de RP corta (RP
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Regulación del sistema nervioso autónomo.
- Electrofisiología Cardíaca Electrofisiología cardíaca.
Sus antecedentes:
- El tiempo de la sístole auricular y ventricular impacta la hemodinámica durante la taquicardia supraventricular (TVS).
- Los cambios reflejos del sistema nervioso autónomo durante la TCS no se comprenden bien.
Objetivo del estudio:
- Para investigar la respuesta refleja del sistema nervioso autónomo a diferentes intervalos atrioventriculares (AV) durante el ritmo DDD simulando SVT.
- Para evaluar la estabilidad hemodinámica y la actividad del nervio simpático (SNA) durante diversas condiciones simuladas de SVT.
Principales métodos:
- Once pacientes con marcapasos permanentes de doble cámara se sometieron al ritmo DDD a 175 bpm.
- La presión arterial registrada (BP), la presión venosa central (CVP) y el SNA muscular en intervalos AV de 30 ms (simultáneos), 200 ms (corto-RP) y 110 ms (largo-RP).
Principales resultados:
- Todos los modos de ritmo causaron una caída en la presión arterial, un aumento de la CVP y un aumento de la ANS.
- La taquicardia con RP prolongada (intervalo AV de 110 ms) mostró una disminución significativamente menor en la presión arterial y un menor aumento en la CVP en comparación con otros modos.
- La sístole estrechamente acoplada (intervalo AV de 30 ms) dio lugar a un aumento significativamente mayor de la ANS en la mayoría de los pacientes.
Conclusiones:
- La taquicardia prolongada de RP se asocia con una estabilidad hemodinámica superior.
- La reducción de la simpatoexcitación durante la taquicardia de RP larga está mediada principalmente por los barorreceptores arteriales.
- Un modesto efecto vasodepresor cardiopulmonar contribuye a la estabilidad hemodinámica durante la taquicardia de larga duración.
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