AUTHOR=Liu Zheng , Xia Yu , Guo Changyan , Li Xiaofeng , Fang Pihua , Yin Xiandong , Yang Xinchun 

TITLE=Low-Voltage Zones as the Atrial Fibrillation Substrates: Relationship With Initiation, Perpetuation, and Termination

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2021.705510

DOI=10.3389/fcvm.2021.705510

ISSN=2297-055X

ABSTRACT=Background: Low voltage zones (LVZ) were usually targeted for ablation in atrial fibrillation (AF). However, its relationship with AF initiation, perpetuation, and termination remains to be studied. This study aimed to explore such relationships.
Methods:  A total of 126 consecutive AF patients were enrolled, including 71 patients for AF induction protocol and 55 patients for AF termination protocol. Inducible and sustainable AF were defined as induced AF lasting over 30 and 300 seconds, respectively. Terminable AF was defined as those could be terminated into sinus rhythm within 1-hour after ibutilide administration. Voltage mapping was performed in sinus rhythm for all patients. LVZ were quantified as the percentage of LVZ area (LVZ%）to left atrium surface area.
Results: The rate of inducible, sustainable and terminable AF were 29.6%, 18.3% and 38.2%, respectively. Inducible AF patients had no significant difference in overall LVZ% as compared with uninducible AF patients (10.2±11.8 vs. 8.5±12.6, P =0.606), while sustainable and interminable AF patients had larger overall LVZ% than unsustainable (16.2±11.5 vs. 0.5±0.7, P <0.001) and terminable AF patients (44.6±26.4 vs. 26.3±22.3, P <0.05), respectively. The segmental LVZ distribution pattern was diverse in different stages of AF. Segmental LVZ% difference was initially observed in anterior wall for patients with inducible AF, and septum was further affected in those with sustainable AF, and roof, posterior wall and floor were finally affected in those with interminable AF.
Conclusions: The associations between LVZ with AF initiation, perpetuation and termination were different depending on its size and distribution.