Complete isolation of the pulmonary veins and posterior left atrium in chronic atrial fibrillation.: Long-term clinical outcome

Aims To evaluate the contribution of the posterior left atrium (LA) to chronic atrial. fibrillation (AF). Methods and results Twenty-seven patients with chronic-AF were studied. After pulmonary vein (PV) isolation, the posterior-LA was isolated by ablation joining the right- and left-PVs using an irrigated-tip catheter. Isolation was demonstrated by absent/dissociated posterior-LA activity and the inability to pace the region. Ablation impact was determined by the effect on cycle length (CL) and AF termination. Posterior-LA isolation was achieved using 35 +/- 12 min of rachofrequency with total fluoroscopic and procedural durations of 64 +/- 16 and 199 +/- 46 min, resulting in abolition of etectrograms (n = 21) or autonomous activity (n = 6; CL 820 +/- 343 ms). AFCL increased from 156 +/- 28 ms to 162 +/- 27 ms with PV-isotation and to 175 +/- 32 ms by posterior-LA exclusion (P < 0.0001). AF persisted in all after PV-isolation and terminated in 5 (19%) during posterior- LA-isolation. After 10 +/- 6 months, 12 patients developed atrial. tachycardia (four) or AF (eight); four underwent repeat posterior-LA-isolation, white the others required additional ablation/antiarrhythmics. After 21 +/- 5 months, 17 (63%) were in sinus rhythm following posterior-LA-isolation. Conclusion This study demonstrates the feasibility of complete posterior-LA exclusion by catheter ablation. This strategy results in maintenance of sinus rhythm in 63% at similar to 2 years follow-up.