Unipolar Electrogram-Guided versus Lesion Size Index-Guided Catheter Ablation in Patients with Paroxysmal Atrial Fibrillation

Abstract

Background: This research explores the relationship between the unipolar electrogram (UP-EGM) and lesion size index (LSI) in different regions of continuous circular lesions (CCLs) and to assess the safety and efficacy of UP-EGM-guided versus LSI-guided radiofrequency catheter ablation (RFCA) in patients with paroxysmal atrial fibrillation (PAF). Methods: A total of 120 patients with drug-refractory PAF who underwent index RFCA were scheduled to be consecutively included from March 2020 to April 2021. All the patients were randomly divided 1:1 into two groups: the UP-EGM group and the LSI group. The first-pass PVI rate, acute PVI rate, and the sinus rhythm maintenance rate were compared. Results: A total of 120 patients with PAF were included in the study: the UP-EGM group (n = 60) and the LSI group (n = 60). All the LSI values in the UP-EGM group were less than those in the corresponding regions in the LSI group (all p < 0.001). There were no significant differences in the first-pass PVI rate and acute PVI rate between the two groups. After a mean follow-up period of 11.31 ± 1.70 months, the sinus rhythm maintenance rate in the UP-EGM group was comparable to that in the LSI group (90% vs. 91.7%, p = 0.752). Conclusion: UP-EGM-guided and LSI-guided RFCA are both effective and safe in patients with PAF. However, UP-EGM may be more suitable than LSI for guiding individual RFCA.

Higher power achieves greater local impedance drop, shorter ablation time, and more transmural lesion formation in comparison to lower power in local impedance guided radiofrequency ablation of atrial fibrillation

“…The elimination of the negative deflection and elevation of the PR segment of the unipolar electrogram have been reported as indicators of transmural lesion formation 13,14 (Figure 1C). The analysis of the unipolar electrogram was performed in 3 patients in whom the unipolar electrogram was recorded during sinus rhythm.…”

“…Recently, high power (HP; 40−50 W) ablation and a short application duration of 5−20 s utilizing AI or LSI has been proposed and was reported to shorten the procedure time 12 . Even though the efficacy of HP ablation using the RHYTHMIA HDx TM system has been reported, 13 study comparing HP ablation with low‐power ablation using the RHYTHMIA HDx TM system with unique ablation target of LI is lacking. The relationship between the difference in ablation power and the ablation efficiency has not been fully investigated.…”

Catheter ablation of atrial fibrillation using FireMagic TrueForce ablation catheter: The TRUEFORCE trial

“…CF and ablation time were incorporated into the weighted algorithmic formula of AI and LSI. However, both AI and LSI have their drawbacks and do not provide a completely accurate assessment of lesion size 23,24 . Moreover, the optimal index values remained uncertain 25–27 .…”

“…However, both AI and LSI have their drawbacks and do not provide a completely accurate assessment of lesion size. 23,24 Moreover, the optimal index values remained uncertain. [25][26][27] EI is a novel index to quantify ablation.…”

New Perspectives on Risk Stratification and Treatment in Patients with Atrial Fibrillation: An Analysis of Recent Contributions on the Journal of Cardiovascular Disease and Development

“…Regarding RFCA optimization, Seidl et al [ 47 ] found that a high-power short-duration ablation was comparable in terms of efficacy rates after one year to the conventional strategy approach. Another interesting analysis showed that unipolar electrogram-guided and lesion size index-guided RCFA were both effective and safe in patients with paroxysmal AF, but unipolar electrogram-guided might be more suitable for guiding RFCA [ 48 ].…”