Characterization and identification of atrial fibrillation drivers in patients with nonparoxysmal atrial fibrillation using simultaneous amplitude frequency electrogram transform

InstructionWe hypothesized that real-time simultaneous amplitude frequency electrogram transform (SAFE-T) during sinus rhythm (SR) is able to identify and characterize the drivers of atrial fibrillation (AF) in nonparoxysmal (NP) AF. MethodsTwenty-one NPAF patients (85.71% males, mean age 52 years old) underwent substrate mapping during SR (SAFE-T and voltage) and during AF (complex fractionated atrial electrograms [CFAE] and similarity index [SI]). After pulmonary veins isolation, extensive substrate ablation was performed with the endpoint of procedural termination or elimination of all SI sites (>63% similarities). Sites with procedural termination and non-termination sites were tagged for postablation SR analysis using SAFE-T. ResultsIn 74 CFAE sites identified (average of 3 +/- 2 sites per person), 28 (37.84%) were identified as termination sites demonstrating a high SI compared with the non-termination sites (80.11 +/- 9.57% vs. 45.96 +/- 13.38%, p < .001) during AF. During SR, these termination sites have high SAFE-T values and harbor a highly resonant, localized, repetitive high frequency components superimposed in the low frequency components compared with non-termination sites (5.70 +/- 3.04 vs. 1.49 +/- 1.66 Hz center dot mV, p < .001). In the multivariate analysis, the termination sites have higher SAFE-T and SI value (p < .001). ConclusionAF procedural termination sites harbored signal characteristics of repetitive, high frequency component of individualized electrogram during SR, which can be masked by the low frequency fractionated electrogram and are difficult to see from the bipolar electrogram. Thus, SAFE-T mapping is feasible in identifying and characterizing sites of AF drivers.

Automated summary

Real-time simultaneous amplitude frequency electrogram transform (SAFE-T) can be used to identify and characterize the drivers of nonparoxysmal atrial fibrillation (NP AF) during sinus rhythm (SR). The study found that termination sites during AF exhibited high similarity index (SI) and high SAFE-T values during SR, indicating the presence of high frequency components. This suggests that SAFE-T mapping is a feasible method for identifying and characterizing AF drivers.