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Respuesta vasopresora a la infusión de angiotensina II en pacientes con insuficiencia cardíaca crónica que reciben
Timothy J Vittorio1, Chim C Lang, Stuart D Katz
1Division of Circulatory Physiology, Columbia Presbyterian Medical Center, New York, NY 10032, USA.
Circulation
|January 23, 2003
Resumen
El carvedilol, un bloqueador beta no selectivo con propiedades de bloqueo alfa1-adrenérgico, redujo la reactividad vascular a la angiotensina II (Ang II) en pacientes con insuficiencia cardíaca crónica en comparación con el metoprolol. Esto sugiere que el carvedilol puede ofrecer beneficios cardiovasculares más allá del bloqueo beta.
Área de la Ciencia:
- Farmacología Cardiovascular Farmacología Cardiovascular
- Insuficiencia cardíaca Fisiopatología Fisiopatología
- Señalización de los receptores adrenérgicos.
Sus antecedentes:
- Se conoce la interacción sinérgica entre el receptor de angiotensina II (Ang II) tipo 1 y los receptores alfa1-adrenérgicos.
- El beta-antagonista no selectivo carvedilol posee propiedades de bloqueo alfa1-adrenérgico.
- Se planteó la hipótesis de una posible modulación de la reactividad vascular a Ang II por carvedilol en pacientes con insuficiencia cardíaca crónica (ICC).
Objetivo del estudio:
- Para comparar la respuesta vasopresora a la infusión de Ang II en pacientes con FHC tratados con carvedilol versus metoprolol.
- Para investigar el papel del bloqueo alfa1-adrenérgico del carvedilol en la modulación de la reactividad vascular a Ang II.
Principales métodos:
- Se estudiaron veinte sujetos con insuficiencia cardíaca congestiva (NYHA clase II/III).
- Los pacientes recibieron carvedilol o metoprolol durante al menos 3 meses, con terapia estandarizada con inhibidores de la ECA.
- Se infundió Ang II exógeno por vía intravenosa para determinar la relación dosis-respuesta (PD20).
Principales resultados:
- La dosis de Ang II requerida para provocar un aumento de la presión sistólica de 20 mm Hg (PD20) fue significativamente mayor en los pacientes tratados con carvedilol (20 ng / kg) en comparación con el metoprolol (5 ng / kg) (P = 0,019).
- No se encontró correlación entre los niveles plasmáticos de Ang II y la PD20.
- El carvedilol atenuó significativamente la respuesta vasopresora a la infusión de Ang II.
Conclusiones:
- La respuesta vasopresora a la infusión de Ang II es significativamente menor en los pacientes con CHF tratados con carvedilol en comparación con el metoprolol.
- Las propiedades de bloqueo alfa1-adrenérgico del carvedilol pueden contribuir a esta reactividad vascular reducida.
- Se necesitan más investigaciones para dilucidar los mecanismos detrás del efecto del carvedilol en la respuesta vascular Ang II.
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