Introduction: The most widely practiced ablation(Ab) technique for paroxysmal AF is the isolation of all pulmonary veins (PV). However, PV isolations had much lower success in persistent AF. We hypothesized that this lower success rate is due to the less important role of triggers from PVs in maintenance of persistent AF. Thus, Ab techniques that target the LA/PV junctions that resulted in more LA mass reductions with simultaneous elimination of drivers and triggers could have higher success rate. Methods: We studied 64 consecutive pts (age:68 ± 6 yrs, male: 41) with persistent AF. Pts were blindly randomized in two groups(G1:LA/PVJ, G2: PV). The Ab was guided by the circular mapping catheter (CMC). If 1st randomized Ab technique was unsuccessful then the pt was cross over to the other group. The end point of the study was complete elimination of all PV or LA/PVJ potentials. Results: A total of 39 pts were randomized to the G1 and 25 pts in G2. In baseline venogram showed presence of bi-lateral LA/PVJ in 51/64 pts (79 %). In G1, 28/39 pts had LA/PVJ that was feasible to place the CMC and 26 pts (67%) had successful LA/PVJ Ab. 13 pts from G1 cross over to G2 due to the unsuccessful Ab. A total of 38 pts underwent G2 protocol. All 38 pts had acute success in isolation of all PVs just distal to the ostium. The procedure and fluoro time were not significantly different between the groups. The RF energy delivered was much higher in G1 (41±6 vs 22±6, p < 0.01). G1 had higher incidence of pericarditis (PD) (15 % vs 3 %, p < 0.01) but G2 had higher incidence of PV stenoses (0 % vs 3 %, p< 0.01). The mean follow-up was 12±4 months. The higher recurrence rate was observed in G2 (47%, p < 0.05) when compared to G1 (35 %). All 27 pts who had recurrences of AF underwent 2nd Ab. The most common causes of the recurrences were incomplete isolation of LA/PVJ (56%) or PV (44%) and the remaining pts had tachycardia from non-PV foci (51%). Conclusion: 1) LA/PVJ Ab is feasible in majority of persistent AF pts. 2) LA/PVJ Ab had higher success rate than the PV isolation in persistent AF. 3) Both techniques had similar complications but much higher incidence of PD was observed after the LA/PVJ Ab.
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