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La dirección del vector T diferencia el postpacing de la inversión isquémica de la onda T en las derivaciones
Alexei Shvilkin1, Kalon K L Ho, Michael R Rosen
1Beth Israel Deaconess Medical Center, Boston, Mass 02215, USA.
Circulation
|February 16, 2005
Resumen
La memoria cardíaca (CM) causa una inversión de onda T que imita la isquemia. Los nuevos criterios de ECG que utilizan patrones de ondas T ahora pueden distinguir de manera confiable la CM de la inversión isquémica de ondas T.
Área de la Ciencia:
- Cardiología Cardiología.
- La electrocardiografía es una técnica de electrocardiografía.
Sus antecedentes:
- La inversión precordial de ondas T (TWI), o memoria cardíaca (CM), se asemeja al TWI isquémico.
- Los criterios actuales de ECG no pueden diferenciar de manera confiable entre CM y TWI isquémico.
Objetivo del estudio:
- Para determinar si la CM inducida por el ritmo ventricular derecho exhibe un patrón de TWI distinto en comparación con el TWI isquémico.
- Desarrollar criterios de ECG para diferenciar la CM del TWI isquémico.
Principales métodos:
- Comparación del eje, la polaridad y la amplitud de las ondas T en ECG de 12 derivaciones durante el ritmo sinusal entre los grupos de CM e isquémicos.
- Se analizaron 13 pacientes con CM (aceleración DDD, retraso AV corto) y 47 pacientes isquémicos con TWI precordial.
Principales resultados:
- Una combinación específica de hallazgos del ECG mostró una alta precisión diagnóstica.
- Los criterios incluyeron T(aVL positivo), T(I positivo o isoeléctrico y TWI precordial máximo > TWI(III).
- Esta combinación fue 92% sensible y 100% específica para CM.
Conclusiones:
- La CM inducida por el ritmo del ventrículo derecho crea un patrón de vector T único.
- Este patrón permite una discriminación efectiva del TWI isquémico, independientemente de la afectación de la arteria coronaria.
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