Changes in sinus node function in a rabbit model of heart failure with ventricular arrhythmias and sudden death.
Circulation
; 101(25): 2975-80, 2000 Jun 27.
Article
en En
| MEDLINE
| ID: mdl-10869272
BACKGROUND: Heart failure is associated with profound changes in the balance of the autonomic nervous system, such as vagal withdrawal and increased catecholamine levels. It is not known whether the intrinsic sinus node function changes during the progression of heart failure. METHODS AND RESULTS: We implanted transmitters for Holter recording in an established rabbit model of heart failure (n=9) and observed changes in sinus cycle length and the occurrence of arrhythmias during the progression of heart failure. The in vitro sinus cycle length and the responses to acetylcholine and norepinephrine in the isolated right atria were analyzed in 12 rabbits with heart failure and in 6 control rabbits. In vivo cycle length increased in some animals and decreased in others. Sudden death occurred in 3 of 9 rabbits. These rabbits had developed a shorter cycle length than the surviving rabbits. Ventricular tachycardias developed in all but 1 rabbit. The in vitro sinus cycle length increased in heart failure. The response to acetylcholine also increased in heart failure, whereas the response to norepinephrine was unchanged. CONCLUSIONS: Changes in intrinsic sinus node function during the progression of heart failure cannot explain the observed decreases in heart rate variability and/or baroreflex sensitivity in this disease, because increased responsiveness to acetylcholine would be expected to cause the opposite.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Arritmias Cardíacas
/
Nodo Sinoatrial
/
Gasto Cardíaco Bajo
/
Disfunción Ventricular
Límite:
Animals
Idioma:
En
Revista:
Circulation
Año:
2000
Tipo del documento:
Article
País de afiliación:
Países Bajos