Catheter Ablation for Paroxysmal Atrial Fibrillation

Abstract

Background-Segmental ostial catheter ablation (SOCA) to isolate the pulmonary veins (PVs) and left atrial catheter ablation (LACA) to encircle the PVs both may eliminate paroxysmal atrial fibrillation (PAF). The relative efficacy of these 2 techniques has not been directly compared. Methods and Results-Of 80 consecutive patients with symptomatic PAF (age, 52Ϯ10 years), 40 patients underwent PV isolation by SOCA and 40 patients underwent LACA to encircle the PVs. During SOCA, ostial PV potentials recorded with a ring catheter were targeted. LACA was performed by encircling the left-and right-sided PVs 1 to 2 cm from the ostia and was guided by an electroanatomic mapping system; ablation lines also were created in the mitral isthmus and posterior left atrium. The mean procedure and fluoroscopy times were 156Ϯ45 and 50Ϯ17 minutes for SOCA and 149Ϯ33 and 39Ϯ12 minutes for LACA, respectively. At 6 months, 67% of patients who underwent SOCA and 88% of patients who underwent LACA were free of symptomatic PAF when not taking antiarrhythmic drug therapy (Pϭ0.02). Among the variables of age, sex, duration and frequency of PAF, ejection fraction, left atrial size, structural heart disease, and the ablation technique, only an increased left atrial size and the SOCA technique were independent predictors of recurrent PAF. The only complication was left atrial flutter in a patient who underwent LACA. Conclusions-In patients undergoing catheter ablation for PAF, LACA to encircle the PVs is more effective than SOCA.

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

“…The current study did not randomize patients without linear lesions, thereby precluding comparisons with techniques solely involving PV isolation. Given the concerns regarding potential complications, more extensive posterior LA ablations (as opposed to superior to inferior PV linear lesions alone) were not performed, although this technique may potentially increase single-procedure success rates (3)(4)(5). Also, alternate ablation strategies such as ablation of complex fractionated atrial electrograms, as described by Nademanee et al (9), in addition to PV isolation, may potentially reduce the need for repeat procedures, but this was not evaluated in our patients.…”

“…Ablation strategies that incorporate LA linear lesions appear to have higher success rates than PVI alone (3)(4)(5)7). The technique of performing wider linear ablations in the LA may aid in targeting different substrates that help to maintain or perpetuate AF.…”

“…Ablation of these triggering foci, while beneficial in the treatment of AF, has been associated with significant recurrence rates (3). The contribution of the posterior left atrium (LA) is increasingly recognized as a source of non-PV triggering foci and as a substrate for maintaining AF.…”

“…The contribution of the posterior left atrium (LA) is increasingly recognized as a source of non-PV triggering foci and as a substrate for maintaining AF. This has led to ablation strategies designed to address both of these mechanisms (3)(4)(5).…”

Atrial Electroanatomical Remodeling as a Determinant of Different Outcomes Between Two Current Ablation Strategies: Circumferential Pulmonary Vein Isolation Vs Pulmonary Vein Isolation

“…2,3 However, it has recently been reported that circumferential LA ablation is more effective in eliminating AF than PVI. 4,5 The incremental efficacy of circumferential LA ablation has been suggested to be attributable to a wide reduction in the anatomical and electrical substrate, that is, atrial debulking. 6,7 On the other hand, LA enlargement is accompanied by structural remodeling associated with the substrate of AF.…”