Although a relatively uncommon form of supraventricular tachycardia (SVT), atrial tachycardia tends to be refractory to pharmacologic therapy and is therefore frequently treated with ablative therapy.
Catheter ablative techniques have evolved from open surgical techniques in which the arrhythmia focus was identified using intraoperative mapping and then excised [1,2]. Direct current (DC) shock catheter ablation (fulguration) was used for a short time in small numbers of patients with atrial tachycardia; this technique has been completely supplanted by radiofrequency (RF) catheter ablation.
Radiofrequency catheter ablation (RFCA) techniques and outcomes in patients with atrial tachycardia will be reviewed here. Ablative techniques for the management of atrial fibrillation, and atrial flutter, both typical and atypical flutter, are discussed separately. (See "Radiofrequency catheter ablation to prevent recurrent atrial fibrillation" and "Atrial flutter: Maintenance of sinus rhythm after cardioversion".)
ATRIAL TACHYCARDIAS AMENABLE TO CATHETER ABLATION
Atrial tachycardia may be unifocal or multifocal; some unifocal tachycardias originate in or around the sinus node.
●Unifocal (or ectopic) atrial tachycardia may have an automatic or reentrant mechanism, and a paroxysmal or incessant pattern (waveform 1 and waveform 2 and waveform 3). Most varieties of unifocal atrial tachycardia are amenable to catheter ablation. Like atrial fibrillation, focal atrial tachycardia may arise from the pulmonary venous ostia [3,4]. The pathophysiology appears to be related, but not identical, to that of focal AF . (See "Intraatrial reentrant tachycardia" and "Focal atrial tachycardia" and 'Indications for catheter ablation' below and "Radiofrequency catheter ablation to prevent recurrent atrial fibrillation".)