Catheter ablation of atrial arrhythmias: state of the art.

Catheter ablation is at the forefront of the management of a range of atrial arrhythmias. In this Series paper, we discuss the underlying mechanisms and the current role of catheter ablation for the three most common atrial arrhythmias encountered in clinical practice: focal atrial tachycardia, atrial flutter, and atrial fibrillation. The mechanisms of focal atrial tachycardia and atrial flutter are well understood, and these arrhythmias are amenable to curative catheter ablation with high success rates. In most cases, paroxysmal atrial fibrillation is initiated by triggers located within pulmonary vein musculature. Circumferential ablation to isolate this musculature is associated with high success rates for elimination of paroxysmal atrial fibrillation in selected populations. Because of the problem of recurrent pulmonary vein connection, more than one procedure will be needed in about 30% of patients, and new technologies are being developed to reduce this occurrence. The mechanisms that sustain persistent atrial fibrillation are not well understood and are the subject of continuing investigation. As such, ablation approaches and technologies for this arrhythmia are still evolving.