Video Experimental Relacionado
Updated: Feb 10, 2026
02:31
Phase Transitions and Effect of Intermolecular Forces
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Gradiente de perfusión miocárdica anormal longitudinal, de la base al ápice por mediciones cuantitativas del flujo
M Hernandez-Pampaloni1, F Y Keng, T Kudo
1Department of Molecular and Medical Pharmacology, UCLA School of Medicine, Los Angeles, CA 90095-1735, USA.
Circulation
|August 2, 2001
Resumen
Los factores de riesgo coronario, incluso sin enfermedad de las arterias coronarias (CAD), están relacionados con gradientes anormales del flujo sanguíneo miocárdico (MBF). Esto sugiere cambios tempranos en la circulación coronaria, lo que podría indicar CAD preclínica.
Área de la Ciencia:
- Cardiología Cardiología.
- Cardiología Nuclear Cardiología nuclear.
- Imágenes cardiovasculares por imágenes.
Sus antecedentes:
- Se conoce un gradiente de perfusión miocárdica longitudinal, de la base al ápice, en la enfermedad de las arterias coronarias (CAD).
- Este gradiente se atribuía previamente al estrechamiento coronario difuso.
- El estudio investigó si este gradiente existe en individuos con factores de riesgo coronario pero sin diagnóstico de CAD.
Objetivo del estudio:
- Para determinar si los pacientes con factores de riesgo coronario pero sin CAD exhiben un gradiente de perfusión miocárdica anormal.
- Para evaluar el flujo sanguíneo miocárdico (FMB) utilizando tomografía por emisión de positrones (PET) en estos pacientes.
Principales métodos:
- El flujo sanguíneo miocárdico (MBF) se midió utilizando (13) N-amoniaco y PET en reposo y durante la hiperemia inducida por dipiridamolo.
- Se tomaron medidas en 36 pacientes con factores de riesgo coronario, 36 controles de edad y 28 controles jóvenes.
- El MBF se analizó globalmente, por territorio coronario y en las secciones del ventrículo izquierdo (LV) medio y medio-a-apical.
Principales resultados:
- No se observaron defectos cualitativos de flujo en reposo o durante la hiperemia en ningún grupo.
- Los valores absolutos de MBF fueron similares en los tres territorios coronarios en todos los sujetos.
- Sin embargo, la MBF hiperémica en las secciones de LV media a apical fue significativamente menor que en las secciones de LV media en el grupo "en riesgo" (P<0,004), pero no en los grupos de control.
Conclusiones:
- Existe un gradiente de perfusión longitudinal anormal de la base al ápice en pacientes con factores de riesgo coronario pero sin CAD.
- Este gradiente durante el estrés dipiridamólico sugiere alteraciones funcionales o estructurales de la circulación coronaria.
- Estos hallazgos pueden indicar el desarrollo de aterosclerosis coronaria o CAD preclínica en individuos con factores de riesgo.
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