Pulmonary vein isolation and left atrial catheter ablation using a three-dimensional navigation system for the treatment of atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is often triggered by ectopic foci originating from pulmonary veins (PVs), with the posterior left atrium (LA) comprising part of the substrate for maintenance. Catheter ablation strategies targeting PVs and the posterior LA may be further refined by incorporating technology beyond standard fluoroscopy.

OBJECTIVES: To prospectively assess the usefulness of a navigation sys-tem to guide a radiofrequency catheter ablation strategy, combining PV isolation (PVI) with anatomical LA ablation.

METHODS: Sixty-four patients (51 men; mean [+/- SD] age 52+/-8 years) who were referred for catheter ablation of paroxysmal (n=49) or persistent (n=15) AF underwent this ablation strategy using the NavX system (Endocardial Solutions Inc, USA). Electrical PVI was guided by a circular mapping catheter. Anatomical ablation consisted of lines drawn along the posterior aspect of the LA from the superior PVs to the inferior PVs. NavX was used for the construction of three-dimensional LA and PV maps with projection of mapping and ablation catheters on the image in real time and for tracking of lesions during posterior LA ablation.

RESULTS: Electrical PVI was achieved in 100% of procedures and all patients underwent the linear posterior LA ablation described above. Procedural and fluoroscopy times were 188+/-41 min and 60+/-12 min, respectively. Repeat procedures for AF recurrence were required in 38(59%) patients. After a mean follow-up period of 16+/-10 months, 59(92%) patients remained arrhythmia-free, including 52 (81%) without antiarrhythmic drugs.

CONCLUSIONS: An AF ablation strategy that combines nonfluoroscopic visualization of catheters with electrical PVI and anatomical LA ablation is feasible, safe and effective, but often requires repeat procedures.