Cryoablation time-dependent dose-response effect at minimal temperatures (-80 degrees C): an experimental study.
Europace
; 11(11): 1538-45, 2009 Nov.
Article
em En
| MEDLINE
| ID: mdl-19846431
ABSTRACT
AIMS:
To establish a temporal safety window for cryoablation at minimal temperatures and to assess the electrophysiological and histological changes as a function of the application duration. METHODS ANDRESULTS:
Twenty mini-pigs underwent AV nodal cryoablation at -80 degrees C without prior cryomapping. The duration of the cryoapplication following atrioventricular block (AVB) was randomized to 0, 10, 20, 40, or 60 s. Atrioventricular block was obtained in all animals after a median of 3 (1-8 interquartile range) applications. One week later, AV nodal conduction fully recovered in animals with application duration <10 s, whereas persistent AVB incidence increased as a function of time in animals with longer applications duration. Cryoablation application duration following AVB was the only independent predictor of persistent AVB (OR, 1.116; 95% CI, 1.013-1.229; P = 0.026). There was no difference in lesion location or size between animals with vs. those without persistent AVB at 1 week. However, animals randomized to longer application duration demonstrated higher degree of cell destruction and fibrotic content.CONCLUSION:
In this closed-chest pig model, there was a relation between cryoapplication duration following AVB at -80 degrees C and recovery of conduction. A safety window of at least 10 s was observed in all cases.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Nó Atrioventricular
/
Criocirurgia
/
Bloqueio Atrioventricular
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Sistema de Condução Cardíaco
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article