The novel electrophysiology of complex fractionated atrial electrograms: Insight from noncontact unipolar electrograms

Li Wei Lo, Satoshi Higa, Yenn Jiang Lin, Shih Lin Chang, Ta Chuan Tuan, Yu Feng Hu, Wen Chin Tsai, Hsuan Ming Tsao, Ching Tai Tai, Sugako Ishigaki, Asuka Oyakawa, Minetaka Maeda, Kazuyoshi Suenari, Shih Ann Chen*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32-300 Hz) and NCM virtual unipolar electrograms (0.5-300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2-second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S-wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non-CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF.

Original languageEnglish
Pages (from-to)640-648
Number of pages9
JournalJournal of cardiovascular electrophysiology
Issue number6
StatePublished - Jun 2010


  • Atrial fibrillation
  • Catheter ablation
  • Complex fractionated atrial electrograms
  • Mapping


Dive into the research topics of 'The novel electrophysiology of complex fractionated atrial electrograms: Insight from noncontact unipolar electrograms'. Together they form a unique fingerprint.

Cite this