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La brecha excitable en la taquicardia reentrante nodal atrioventricular. Caracterización con extrastimules
C D Schuger1, R T Steinman, M H Lehmann
1Electrophysiology Laboratory, Wayne State University, Detroit, Michigan.
Circulation
|August 1, 1989
Resumen
Este estudio investigó la brecha excitable en la taquicardia reentrante nodal atrioventricular (AVNRT), encontrando que la intervención farmacológica puede revelar esta brecha, apoyando un mecanismo microreentrante en AVNRT.
Área de la Ciencia:
- Electrofisiología y electrofisiología.
- Cardiología Cardiología.
Sus antecedentes:
- La taquicardia reentrante nodal atrioventricular (AVNRT, por sus siglas en inglés) es una taquicardia supraventricular común.
- Comprender el sustrato electrofisiológico de AVNRT es crucial para una gestión efectiva.
Objetivo del estudio:
- Para caracterizar la brecha excitable durante el AVNRT.
- Para dilucidar el sustrato electrofisiológico de esta arritmia microreintrant.
- Para evaluar el efecto del verapamil en la brecha excitable.
Principales métodos:
- Entrega de extrastimulos ventriculares (V2) durante AVNRT en 11 pacientes.
- Medición de la preexcitación auricular y el restablecimiento de la taquicardia.
- Administración de verapamil para evaluar su efecto sobre la brecha excitable.
Principales resultados:
- Una brecha excitable estaba presente en el 45% de los pacientes al inicio.
- El verapamil amplió la zona de preexcitación y aumentó la preexcitación auricular máxima.
- AVNRT se restableció constantemente por V2, con un patrón de respuesta creciente después de verapamil.
Conclusiones:
- Un número significativo de pacientes con AVNRT tiene una brecha excitable, que puede ser mejorada por verapamil.
- El creciente patrón de respuesta de restablecimiento apoya un mecanismo de reentrada en AVNRT.
- La presencia de una brecha totalmente excitable sugiere un circuito de microreentrada que involucra un obstáculo anatómico.
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