Use of ICE for RF ablation of AF.

摘要

Catheter ablation of atrial fibrillation (AF) continues to gain popularity. Despite little to suggest that an improvement in longevity can be achieved through aggressive restoration of sinus rhythm, AF often proves highly symptomatic and its management a challenge. Although atrioventricular (AV) node ablation and pacemaker implantation can regularize heart rate and improve symptoms in many patients with refractory symptomatic AF, there are legitimate concerns over rendering patients' pacemaker dependent unless other options are not available. As a result, the quest for a perfect AF ablation protocol continues. As with many areas in medicine, our understanding grows as we attempt to perfect our techniques and tools.Over time, AF ablation has moved from the creation of linear lesions to the isolation of pulmonary veins (PV) when the former, using older tools, was found lacking in success and high in complications. Approaching focal ablation with tight circumferential lesions was associated with relatively high rates of PV stenosis and hence, lesions were moved further away from the PV os to create large circumferential lesions encompassing pairs of PV. As these lesions moved away from the os, in addition to isolation, substrate modification was performed through the creation of significant atrial conduction/innervation alterations. Hence, we have again moved on from focal isolation to focal plus substrate modification. While most agree that ablation in the normal or near-normal heart is most likely to be successful with the least likelihood of complications, the boundaries continue to be pushed in terms of finding the acceptable AF ablation candidate pool and techniques. Still lacking, of course, is substantiation of the extent over time that patients derive benefit from AF ablation.