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Relación entre el "robo" coronario y la función contráctil en reposo en el miocardio dependiente de colateral de
G Holmvang1, S Fry, H A Skopicki
1Departments of Medicine (Cardiac Unit), Radiology, and Nuclear Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Circulation
|May 20, 1999
Resumen
El robo coronario, una disminución en el flujo sanguíneo durante las pruebas de estrés de adenosina, está fuertemente relacionado con la disfunción contráctil en reposo en los segmentos del corazón dependientes de la colateral. Este hallazgo sugiere que el robo coronario contribuye significativamente al deterioro crónico en algunos pacientes con enfermedades cardíacas.
Área de la Ciencia:
- Cardiología Cardiología.
- Cardiología Nuclear Cardiología nuclear.
- Enfermedad Isquémica del Corazón.
Sus antecedentes:
- Se hipotetiza que la asinergia en reposo en el miocardio dependiente de colateral se correlaciona con el robo coronario.
- El robo coronario es un fenómeno en el que el flujo sanguíneo disminuye durante la hiperemia en áreas dependientes de collateral.
Objetivo del estudio:
- Investigar la relación entre la función contráctil miocárdica en reposo y el robo coronario en pacientes con enfermedad cardíaca isquémica crónica.
- Determinar el papel del acelerador coronario frente a la reserva de flujo reducido en el deterioro contráctil crónico.
Principales métodos:
- La tomografía por emisión de positrones (PET) con [13N] amoníaco se utilizó para medir el flujo sanguíneo miocárdico y la reserva de flujo.
- La angiografía coronaria evaluó la gravedad de la estenosis y el suministro colateral.
- La ecocardiografía o la ventriculografía de contraste evalúan el movimiento regional de la pared.
Principales resultados:
- Los segmentos dependientes de la colateral con "steal" (una disminución en el flujo con adenosina) mostraron un mayor flujo sanguíneo en reposo en comparación con los segmentos sin steal o con contracción normal.
- Si bien la reserva de flujo fue mayor en segmentos que normalmente se contraen, hubo una superposición significativa.
- Los segmentos que demuestran acero casi invariablemente exhiben sinergia en reposo (22/23), mientras que los segmentos no siderúrgicos muestran sinergia con menos frecuencia (24/39).
Conclusiones:
- El robo coronario, identificado por una disminución en el flujo sanguíneo del miocardio durante el estrés por adenosina, está fuertemente asociado con la disfunción contráctil en reposo en segmentos dependientes de la colateral.
- El robo coronario parece ser un factor significativo en la patogénesis del deterioro crónico de la contractilidad en pacientes seleccionados.
- La simple reducción de la reserva de flujo miocárdico puede ser menos crítica que el robo coronario para causar disfunción contráctil crónica en estos pacientes.
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