Reduction in atrial defibrillation threshold by a single linear ablation lesion.
J Cardiovasc Electrophysiol
; 12(4): 463-71, 2001 Apr.
Article
en En
| MEDLINE
| ID: mdl-11332570
ABSTRACT
INTRODUCTION:
This study investigated a hybrid approach to reduce the atrial defibrillation threshold (ADFT) by determining the effect of a single linear radiofrequency ablation (RFA) lesion on both the ADFT and activation patterns during atrial fibrillation (AF). METHODS ANDRESULTS:
In 18 open chest sheep (45 to 57 kg), coil defibrillation electrodes were placed in a superior vena cava/right ventricular configuration. AF was induced by burst pacing and maintained with acetyl beta-methylcholine (2 to 42 microL/min). ADFTs were obtained before and after a linear RFA lesion was created in the left atrium (LAL; n = 6), right atrium (RAL; n = 6), or neither atrium as a control (n = 6). In animals receiving an LAL, a 504-unipolar-electrode plaque was sutured to the LA. For animals receiving an RAL, two 504-electrode plaques were placed, one each on the LA and RA. From each plaque, activations were recorded before and after ADFT shocks, and organizational characteristics of activations were analyzed using algorithms that track individual wavefronts. In sham-treated controls, the ADFT did not change. In contrast, LAL reduced ADFT energy 29%, from 4.5 +/- 2.3 J to 3.2 +/- 2.0 J (P < 0.05). RAL reduced ADFT energy 25%, from 2.0 +/- 0.9 J to 1.5 +/- 0.7 J (P < 0.05). AF activation was substantially more organized after RFA than before RFA for both the RAL- and LAL-treated animals.CONCLUSION:
A single RFA lesion in either the RA or LA reduces the ADFT in this sheep model. This decrease is associated with an increase in fibrillatory organization.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fibrilación Atrial
/
Cardioversión Eléctrica
/
Ablación por Catéter
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Cardiovasc Electrophysiol
Asunto de la revista:
ANGIOLOGIA
/
CARDIOLOGIA
/
FISIOLOGIA
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA