Current perspectives on curative catheter ablation of atrial fibrillation
- Hôpital Cardiologique du Haut-Lévêque, Avenue de Magellan, 33604 Pessac Cedex, France
- Correspondence to:
Dr Dipen C Shah, Hôpital Cardiologique du Haut-Lévêque, Avenue de Magellan, 33604 Pessac Cedex, France;
Following the remarkable success of catheter based ablation techniques in curing regular supraventricular tachycardias, attention has turned to atrial fibrillation
Following the remarkable success of catheter based ablation techniques in curing regular supraventricular tachycardias, the attention of the electrophysiological community has turned upon atrial fibrillation based on the assumption that if surgical incisions with a knife can be duplicated by point by point lesions, a catheter based technique should provide results equivalent to the Maze procedure. Considering that transmurality is an inherent accompaniment of each knife incision, that a surgical atriotomy is much narrower than anything that catheters can currently achieve, and that lesion continuity and placement is assured under direct vision in the surgical field, it is not surprising to note the difficulty encountered in reproducing surgical results by catheter based techniques.
INITIAL ATTEMPTS AT LINEAR ABLATION
Two early studies attempted to intervene in both atria1,2: one in a progressive incremental fashion and the other more directly imitating the surgical Maze with a biatrial approach. The essential lessons learned from these studies (and supported by more recent ones3) were: that creating continuous linear lesions to duplicate surgical atriotomies was difficult; that right atrial lesions alone were safe but ineffective; that left atrial lesions improved success rates though at a significant morbidity (including proarrhythmic left atrial re-entry) and even mortality cost; but most importantly perhaps, both studies showed the feasibility of cure by catheter based techniques in patients with paroxysmal and persistent atrial fibrillation.
RECOGNITION OF INITIATION FROM THE PULMONARY VEINS
These linear ablation procedures afforded the possibility of observing shortened paroxysms of atrial fibrillation at close quarters with mapping catheters in the left atrium. Stereotyped initiations were traced in nearly all patients to sleeves of atrial myocardium encasing the ostia of one or more pulmonary veins.4 Isolated or multiple discharges culminating in paroxysms of atrial fibrillation …