Under biatrial dilation, left atrial (4/11 hearts; P<0.05) and biatrial ablation (16/21; P<0.01), but not right atrial ablation (0/10; P=NS), reduced the inducibility of sustained AF.
Does linear radiofrequency ablation of the right, left, or both atria reduce the inducibility of sustained atrial fibrillation in a rabbit heart model of atrial dilation?
In a rabbit model of atrial dilation, left atrial and biatrial linear ablation, but not right atrial ablation, significantly reduced the inducibility of sustained atrial fibrillation.
INTRODUCTION: Atrial dilation associated with increasing atrial pressure plays an apparent role in the development of atrial fibrillation (AF). We characterized a new model of separate and biatrial dilation in the Langendorff-perfused rabbit heart. The aim of this study was to examine if sustained AF in this model (1) would be inducible by separate right atrial (RA) and left atrial (LA) dilation; (2) would be reproducibly inducible at the same pressure level; and (3) could be suppressed by RA, LA, or biatrial ablation. METHODS AND RESULTS: Intra-atrial pressure was increased stepwise in the RA (n = 13), LA (n = 12), or both atria (n = 25) until sustained AF could be induced or a pressure of 20 cm H2O was reached. The stimulation protocol was repeated once in RA and LA dilation (n = 9) and three times in biatrial dilation (n = 7). Then, RA orifices (superior and inferior caval veins, tricuspid valve annulus, and foramen ovale) or LA orifices (pulmonary veins, mitral valve annulus, and foramen ovale) were connected by radiofrequency (RF) lesions. Sustained AF was rendered inducible in 100% of hearts with biatrial dilation, but in only 92% of hearts with RA dilation and 67% with LA dilation. Inducibility of sustained AF was reproducible. Under biatrial dilation, not RA ablation (0/10 hearts; P = NS) but LA ablation (4/11 hearts; P < 0.05) and biatrial ablation (16/21; P < 0.01) reduced the inducibility of sustained AF. CONCLUSION: The inducibility of sustained AF due to increased intra-atrial pressure differs between the RA and LA. LA and biatrial lesions, not RA RF lesions, reduce the ability to perpetuate sustained AF.
Zarse et al. (Fri,) conducted a other in Atrial fibrillation (n=50). Radiofrequency ablation (RA, LA, or biatrial) was evaluated on Reduction in inducibility of sustained AF. Under biatrial dilation, left atrial (4/11 hearts; P<0.05) and biatrial ablation (16/21; P<0.01), but not right atrial ablation (0/10; P=NS), reduced the inducibility of sustained AF.