Catheter ablation for the treatment of atrial tachycardia.

Radiofrequency (RF) catheter ablation has revolutionized the treatment of supraventricular tachycardia, particularly those caused by atrioventricular nodal reentry and Wolff-Parkinson-White syndrome. Recently, RF catheter ablation has also been used to treat atrial flutter (AFL), focal automatic atrial tachycardia, and intra-atrial reentrant tachycardia. Typical AFL is caused by reentry in the right atrium, with an area of slow conduction in the isthmus between the inferior vena cava and tricuspid valve annulus. Ablation of exit sites from the isthmus near the coronary sinus ostium, or the isthmus itself, may cure AFL in the majority of patients. Intra-atrial reentrant tachycardia also has an area of slow conduction where application of RF energy is curative in most patients. In this arrhythmia, which is particularly common after congenital heart disease surgery, the reentrant circuit may occur in the right or left atrium. Focal automatic atrial tachycardia is probably caused by abnormal automaticity and, although it may arise from the right or left atrium, is easily ablated in most patients. Thus, RF catheter ablation is a highly effective alternative to pharmacologic therapy for treating atrial tachycardia, and it is likely to be increasingly used as curative therapy in the future.