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Gradientes subvalvulares en pacientes con estenosis valvular aórtica: prevalencia, magnitud e importancia fisiológica
1Division of Cardiology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA. wlaskey@ medicine.umaryland.edu
Circulation
|August 29, 2001
Resumen
Los gradientes subvalvulares son comunes en la estenosis aórtica, con un promedio de casi la mitad del gradiente total. El ejercicio aumenta significativamente estos gradientes e impacta inversamente en el rendimiento cardíaco, con gradientes subvalvulares que predicen la respuesta.
Área de la Ciencia:
- Cardiología Cardiología.
- Fisiología cardiovascular fisiología cardiovascular.
- Diagnóstico médico Diagnóstico médico
Sus antecedentes:
- Los gradientes subvalvulares en la estenosis aórtica son conocidos, pero poco comprendidos.
- Su comportamiento dinámico durante el ejercicio sigue sin caracterizarse.
Objetivo del estudio:
- Para caracterizar los gradientes subvalvulares en la estenosis aórtica.
- Para investigar su respuesta al ejercicio supino.
- Para determinar la relación entre los gradientes y la respuesta de salida cardíaca.
Principales métodos:
- Manómetro de punta de catéter utilizado para mediciones de presión y velocidad.
- Medidas tomadas en reposo y durante el ejercicio supino.
- El estudio incluyó a 27 pacientes con estenosis aórtica valvular.
Principales resultados:
- Los gradientes subvalvulares promediaron el 48% del gradiente total en reposo.
- Tanto los gradientes totales como los subvalvulares aumentaron significativamente con el ejercicio.
- El gradiente subvalvular del ejercicio, pero no el total, predice la respuesta de salida cardíaca.
Conclusiones:
- Los gradientes de presión subvalvular están universalmente presentes en la estenosis aórtica severa.
- Estos gradientes constituyen aproximadamente la mitad del gradiente transvalvular total.
- El aumento del rendimiento cardíaco del ejercicio está inversamente relacionado con la magnitud del gradiente subvalvular.
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