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Estimulación selectiva de las fibras nerviosas parasimpáticas al nodo sinoatrial humano
1Department of Pathology, University Hospitals of Cleveland/Case Western Reserve University, Ohio 44106.
Circulation
|April 1, 1992
Resumen
Las fibras nerviosas parasimpáticas en las almohadillas de grasa epicárdicas humanas pueden estimularse para aumentar la longitud del ciclo auricular. Esta estimulación selectiva de los nervios del nodo sinoatrial no afectó la conducción atrioventricular.
Área de la Ciencia:
- Cardiología Cardiología.
- La neurociencia es la neurociencia.
- El sistema nervioso autónomo.
Sus antecedentes:
- Las fibras nerviosas parasimpáticas que innervan el nodo sinoatrial en los animales pueden aumentar la longitud del ciclo auricular.
- Estos nervios están ubicados en las almohadillas de grasa epicárdicas cerca del nodo sinoatrial.
- Se planteó la hipótesis de la existencia y la estimulación de nervios similares en los seres humanos.
Objetivo del estudio:
- Para investigar la presencia de nervios parasimpáticos en las almohadillas de grasa epicárdicas humanas.
- Para determinar si estos nervios pueden ser estimulados selectivamente para influir en la frecuencia cardíaca.
- Para evaluar el efecto de la estimulación en la longitud del ciclo auricular y la conducción atrioventricular.
Principales métodos:
- Examen microscópico de las almohadillas de grasa epicárdica obtenidas por autopsia en humanos.
- Estimulación eléctrica de las almohadillas de grasa epicárdicas en 16 pacientes de cirugía cardíaca.
- Variando las frecuencias de estimulación (6.6-30 Hz) y midiendo la longitud del ciclo auricular y el intervalo PR.
Principales resultados:
- Se identificaron fibras nerviosas y ganglios en las almohadillas de grasa epicárdicas humanas.
- La estimulación eléctrica aumentó significativamente la duración del ciclo auricular de una manera dependiente de la frecuencia.
- El tiempo de conducción atrioventricular y el intervalo PR se mantuvieron sin cambios durante la estimulación.
Conclusiones:
- Las fibras nerviosas parasimpáticas en las almohadillas de grasa epicárdicas humanas pueden ser estimuladas selectivamente.
- Esta estimulación aumenta efectivamente la longitud del ciclo atrial sin afectar la conducción nodal atrioventricular.
- Este estudio representa la primera estimulación selectiva de los nervios inervadores del nodo sinoatrial en humanos.
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