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Mecanismos de control para la hipertrofia fisiológica del embarazo
S M Mone1, S P Sanders, S D Colan
1Department of Cardiology, Children's Hospital, Boston, MA 02115, USA.
Circulation
|August 15, 1996
Resumen
El embarazo causa una disminución temporal de la contractilidad cardíaca, que se maneja mediante cambios en la presión arterial y el volumen. El corazón se adapta a su tamaño para mantener la función durante y después del embarazo.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- La Medicina Reproductiva es una de ellas.
- La remodelación cardíaca remodelación cardíaca.
Sus antecedentes:
- El embarazo sirve como modelo para la hipertrofia fisiológica y la atrofia debido a los cambios hemodinámicos.
- Investigó el impacto del embarazo en la mecánica ventricular.
Objetivo del estudio:
- Para probar la hipótesis de que la adaptación cardíaca durante el embarazo actúa como un servomecanismo.
- Para identificar la tensión de la pared como la variable de retroalimentación clave en este proceso.
Principales métodos:
- Estudios en serie en 33 mujeres durante y después de la gestación normal.
- Índices de contractilidad independientes de la carga utilizados.
- Se monitorean las dimensiones ventriculares, el grosor de la pared y la masa ventricular izquierda.
Principales resultados:
- El acortamiento fraccionario y la velocidad del acortamiento disminuyeron durante el embarazo.
- El índice cardíaco aumentó, con la tensión máxima de la pared elevada temprano y luego se normalizó debido a la hipertrofia compensatoria.
- Cambios de masa del ventrículo izquierdo correlacionados con el estrés máximo de la pared.
Conclusiones:
- El embarazo normal implica una disminución reversible de la contractilidad cardíaca.
- La función sistólica se mantiene por la reducción de la carga posterior, pero disminuye a corto plazo.
- La hipertrofia / atrofia ventricular izquierda está vinculada a la carga hemodinámica, lo que sugiere un servomecanismo.
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