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Resultados a largo plazo en individuos con intervalo PR prolongado o bloqueo atrioventricular de primer grado
Susan Cheng1, Michelle J Keyes, Martin G Larson
1Framingham Heart Study, Framingham, Massachusetts, USA.
JAMA
|June 25, 2009
Resumen
El intervalo PR prolongado, un signo de bloqueo atrioventricular de primer grado, aumenta significativamente el riesgo de fibrilación auricular (FA), implantación de marcapasos y mortalidad por todas las causas en individuos ambulatorios.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- La medicina preventiva es la medicina preventiva de las enfermedades.
Sus antecedentes:
- El bloqueo atrioventricular de primer grado, definido por un intervalo de PR superior a 200 milisegundos, es un hallazgo electrocardiográfico común.
- La importancia clínica de la prolongación de la PR en individuos asintomáticos requiere una mayor aclaración.
Objetivo del estudio:
- Investigar las implicaciones clínicas a largo plazo de la prolongación del intervalo PR en una cohorte basada en la comunidad.
- Evaluar la asociación entre la prolongación de la PR y la incidencia de fibrilación auricular, implantación de marcapasos y mortalidad por cualquier causa.
Principales métodos:
- Estudio prospectivo de cohorte basado en la comunidad de 7.575 individuos del Framingham Heart Study.
- Electrocardiografía de 12 conductos de referencia con evaluación del intervalo PR.
- Seguimiento prospectivo hasta 2007, utilizando modelos de riesgos proporcionales de Cox ajustados por multivariables.
Principales resultados:
- Las personas con intervalos de PR >200 ms tenían tasas de incidencia significativamente más altas de fibrilación auricular (FA), implantación de marcapasos y mortalidad por todas las causas.
- Cada incremento de 20 ms en el intervalo PR se asoció con un aumento de los ratios de riesgo ajustados para AF, implantación de marcapasos y mortalidad por todas las causas.
- El bloqueo atrioventricular de primer grado confería un riesgo ajustado de FA de 2 veces, un riesgo de implantación de marcapasos de 3 veces y un riesgo de mortalidad por cualquier causa de 1,4 veces.
Conclusiones:
- La prolongación del intervalo PR es un predictor independiente significativo de los resultados cardiovasculares adversos.
- La identificación de individuos con intervalos de PR prolongados puede ayudar en la estratificación del riesgo y las estrategias preventivas.
- Este hallazgo subraya la importancia de la evaluación electrocardiográfica en la práctica clínica de rutina.
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