Clinical outcome of left atrial ablation for paroxysmal atrial fibrillation is related to the extent of radiofrequency ablation.
BACKGROUND
The exact mechanism of eliminating atrial fibrillation (AF) by catheter ablation techniques is not known. We investigated whether the extent of atrial damage conferred by radiofrequency lesions is a predictor of success after ablation, regardless of the method employed for ablation.


METHODS
Ninety consecutive patients with paroxysmal AF subjected to ostial-antral pulmonary vein isolation (n = 41) or circumferential (n = 49) catheter ablation were studied.


RESULTS
At 1 year follow-up, 16 out of 41 patients (39%) with ostial-antral ablation and 16 out of 49 patients (32.6%) with circumferential ablation had AF recurrences (p = 0.5). The mean duration of radiofrequency ablation lesions was statistically significantly shorter in patients with recurrence of AF compared to those with sinus rhythm 1 year after ablation (22.3 +/- 4.2 min vs. 27.2 +/- 4.5 min, respectively, p value < 0.001). Radiofrequency ablation time was inversely associated with the risk of recurrence of AF 1 year after ablation and this relationship remained even after adjustment for potential confounding factors such as age, sex, left atrial size, and type of ablation technique (ostial-antral or circumferential; HR = 0.80, 95% CI: 0.72-0.87, p < 0.001).


CONCLUSIONS
Duration of radiofrequency energy delivery is an independent predictor of clinical outcome at 1 year follow-up both among patients undergoing circumferential as well as ostial-antral ablation.
Katritsis
Demosthenes
D
Department of Cardiology, Athens Euroclinic, 9 Athanassiadou Street, Athens 11521, Greece. dkatritsis@euroclinic.gr
Ellenbogen
Kenneth A
KA
Giazitzoglou
Eleftherios
E
Sougiannis
Dimitrios
D
Paxinos
George
G
Fragakis
Nicolaos
N
Camm
A John
AJ
D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D018572:Disease-Free Survival; D005260:Female; D006325:Heart Atria / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery; D012008:Recurrence