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Efecto perjudicial de la braquiterapia coronaria en la respuesta vasomotora al ejercicio
Mario Togni1, Stephan Windecker, Peter Wenaweser
1Swiss Cardiovascular Center, Inselspital, Bern, Switzerland.
Circulation
|July 1, 2004
Resumen
La braquiterapia intracoronaria para la restenosis del stent elimina la vasodilatación inducida por el ejercicio en las arterias coronarias. Si bien se mantiene la respuesta de la nitroglicerina, esto sugiere una disfunción endotelial después del tratamiento con radiación.
Área de la Ciencia:
- Medicina Cardiovascular La medicina cardiovascular es una especialidad de la salud.
- Cardiología Intervencionista Cardiología intervencionista.
- Radioncología Oncología de la radiación.
Sus antecedentes:
- La braquiterapia intracoronaria es un tratamiento propuesto para la restenosis en el stent.
- Los efectos a largo plazo sobre la integridad vascular y la capacidad de respuesta vasomotora siguen siendo desconocidos.
Objetivo del estudio:
- Para determinar la respuesta vasomotora después de la braquiterapia intracoronaria.
- Para evaluar la influencia de la braquiterapia en la movilidad vascular durante el ejercicio.
Principales métodos:
- Angiografía coronaria cuantitativa en biplano en reposo y durante el ejercicio.
- Comparación de 14 pacientes después de la colocación de un stent (control) y 13 después de la braquiterapia para la restenosis del stent (20 Gy).
- Análisis del área luminal mínima, el área del stent y el área del vaso de referencia.
Principales resultados:
- Los vasos de referencia mostraron vasodilatación inducida por el ejercicio en ambos grupos.
- La vasomoción dentro de los segmentos con stent fue abolida.
- El grupo de braquiterapia exhibió vasoconstricción inducida por el ejercicio en los segmentos proximal/distal, a diferencia de los controles.
Conclusiones:
- Los segmentos normales muestran vasodilatación mediada por flujo durante el ejercicio.
- La colocación de un stent no afecta la respuesta al ejercicio proximal/distal.
- La braquiterapia elimina la vasodilatación inducida por el ejercicio, lo que indica una disfunción endotelial a pesar de la respuesta de nitroglicerina preservada.
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