Ethanol infusion in patients with non-paroxysmal atrial fibrillation
Catheter ablation for patients with non-paroxysmal AF remains challenging. The Star AF II trial demonstrated that the rate of freedom from AF was 60% in patients underwent PVI alone at 12 months after the procedure.16 The trial did not show any differences among the three ablation strategies: PVI alone, PVI plus electrograms, and PVI plus lines. However, complete conduction block across both lines was achieved in 74% of the group assigned to PVI plus lines. This means that full achievement of MI block line is crucial for precisely estimating the efficacy of linear ablation in the left atrium. Our present study demonstrated a higher rate of 96% (128/133) in the EIVOM/ RF group and 92% (318/346) in the RF group regarding creating a complete MI block line during the procedure. AF- and AT-free survival rate at 12 months after the procedure was 70% in both groups.
A recent, prospective, multicenter, randomized clinical trial (VENUS-AF trial) comparing these two procedures was published.17,18 The VENUS-AF trial demonstrated that EIVOM/RF reduced recurrence of AF or AT. In this trial, bidirectional MI block line was obtained in 51.3% of the group in which ablation was performed by only RF. Meanwhile, our study did not show a superiority of the EIVOM/RF group compared to the RF group regarding clinical outcome. We anticipated that the result was caused by a high success rate of MI complete block in the RF group. However, AF recurrences were naturally caused by PV reconnections. PV reconnections were observed in 55% of the RF group, and 70% of the EIVOM/RF group. The concern that these findings would have an effect on AF recurrence remains.