New mapping for determination of left atrial posterior wall isolation for non-paroxysmal atrial fibrillation

Abstract

Abstract Background Recent studies have reported that the efficacy of posterior wall isolation(PWI) created by cryoballoon for non-paroxysmal atrial fibrillation. However, there are no clear criteria for determining whether or not to perform PWI, and it is left to the discretion of the operator. Then we evaluated the necessity of additional PWI by measuring non-passively activated ratios(%NP), the ratio of the form of rotors and multiple wavelets, using ExTRa mapping and verified its usefulness. Methods and Results 44 patients with non-paroxysmal atrial fibrillation who underwent cryoballoon ablation(CBA) were divided into two groups according to whether using ExTRa mapping(ExTRa group; 21 patients) or not(no-ExTRa group; 23 patients), and the long-term results were compared. In ExTRa group, ExTRa mapping was performed before PVI, after PVI, and after roof block(LA-RB) creation using cryoballoon. After creating LA-RB, if more than 50% of %NP remained in the left atrium, PWI was performed by creating a bottom block(LA-BB) using cryoballoon. After a median follow-up period of 12months(2 to 34 months), arrhythmia-free survival rate was higher in the ExTRa group than in the no-ExTRa group(95.2% vs 69.6%, p<0.05%). Conclusion Evaluation of %NP using ExTRa mapping is extremely useful in determining the additional PWI for non-paroxysmal atrial fibrillation.Voltage mapping & ExTRa mapping