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Alternantes de ondas T de microvoltaica como predictor de taquiarritmias ventriculares: un estudio prospectivo
Kaoru Tanno1, Syunsho Ryu, Norikazu Watanabe
1Third Department of Internal Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan. k-tanno@p02.itscom.ne
Circulation
|April 7, 2004
Resumen
Los pacientes con alternantes de ondas T de microvolt (TWA) en ritmos cardíacos más bajos muestran un mayor riesgo de taquiarritmias ventriculares. Este hallazgo pone de relieve la importancia de la frecuencia cardíaca en la evaluación de TWA para el riesgo de muerte cardíaca súbita.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- Investigación de la arritmia cardíaca Investigación de la arritmia cardíaca.
Sus antecedentes:
- Los alternantes de ondas T de microvoltaica (TWA) son un marcador reconocido para la muerte súbita cardíaca (SCD) y la taquicardia ventricular (VT).
- Investigaciones anteriores indican una correlación significativa entre la manifestación de TWA y la frecuencia cardíaca.
- La influencia de la frecuencia cardíaca en el valor predictivo de TWA para las taquiarritmias ventriculares requiere más investigación.
Objetivo del estudio:
- Investigar la relación entre el TWA detectado en ritmos cardíacos más bajos y el riesgo de taquiarritmias ventriculares.
- Para determinar si los pacientes que exhiben TWA a la reducción de la frecuencia cardíaca son más vulnerables a las arritmias potencialmente mortales.
Principales métodos:
- Se realizaron estudios electrofisiológicos en 248 pacientes entre 1997 y 2000.
- TWA se registró en el ritmo sinusal y durante el ritmo auricular a ritmos de 90, 100, 110 y 120 bpm.
- Se midió el voltaje de los alternantes (V(alt)) y se realizó un seguimiento de los pacientes para VT, VF, SCD o terapia adecuada con desfibrilador cardioverter implantable.
Principales resultados:
- Se observó una mayor incidencia de VT / VF / SCD en pacientes con V ((alt) > 1.9 microV a 90, 100 y 110 bpm (56%, 28%, 18% respectivamente).
- Un V (alt) de >2.9 microV a 90 bpm mostró un valor predictivo positivo del 70% para VT/VF/SCD.
- Una V (alt) <0,9 microV a 120 bpm demostró un valor predictivo negativo del 100%, lo que sugiere seguridad en la frecuencia cardíaca más alta.
Conclusiones:
- Los pacientes con TWA detectados en ritmos cardíacos relativamente bajos exhiben una mayor susceptibilidad a las taquiarritmias ventriculares.
- La frecuencia cardíaca es un factor crítico en la interpretación de la TWA para la estratificación del riesgo de muerte cardíaca súbita.
- Estos hallazgos subrayan la importancia de considerar la frecuencia cardíaca al evaluar el TWA para el riesgo de arritmia.
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