The isthmus characteristics of scar-related macroreentrant atrial tachycardia in patients with and without cardiac surgery

Shin Huei Liu, Yenn Jiang Lin*, Po Tseng Lee, Jennifer Jeanne Vicera, Shih Lin Chang, Li Wei Lo, Yu Feng Hu, Fa Po Chung, Ta Chuan Tuan, Tze Fan Chao, Jo Nan Liao, Ting Yung Chang, Chin Yu Lin, Cheng I. Wu, Chih Min Liu, Wen Han Cheng, Shih Ann Chen

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


Introduction: Identifying the critical isthmus (CI) in scar-related macroreentrant atrial tachycardia (AT) is challenging, especially for patients with cardiac surgery. We aimed to investigate the electrophysiological characteristics of scar-related macroreentrant ATs in patients with and without cardiac surgery. Methods: A prospective study of 31 patients (mean age 59.4 ± 9.81 years old) with scar-related macroreentrant ATs were enrolled for investigation of substrate properties. Patients were categorized into the nonsurgery (n = 18) and surgery group (n = 13). The CIs were defined by concealed entrainment, conduction velocity less than 0.3 m/s, and the presence of local fractionated electrograms. Results: Among the 31 patients, a total of 65 reentrant circuits and 76 CIs were identified on the coherent map. The scar in the surgical group is larger than the nonsurgical group (18.81 ± 9.22 vs. 10.23 ± 5.34%, p =.016). The CIs in surgical group have longer CI length (15.27 ± 4.89 vs. 11.20 ± 2.96 mm, p =.004), slower conduction velocity (0.46 ± 0.19 vs. 0.69 ± 0.14 m/s, p <.001), and longer total activation time (45.34 ± 9.04 vs. 38.24 ± 8.41%, p =.016) than those in the nonsurgical group. After ablation, 93.54% of patients remained in sinus rhythm during a follow-up of 182 ± 19 days. Conclusion: The characteristics of the isthmus in macroreentrant AT are diverse, especially for surgical scar-related AT. The identification of CIs can facilitate the successful ablation of scar-related ATs.

Original languageEnglish
Pages (from-to)1921-1930
Number of pages10
JournalJournal of cardiovascular electrophysiology
Issue number7
StatePublished - Jul 2021


  • conduction isthmus
  • conduction velocity
  • electroanatomical map
  • scar-related macroreentrant tachycardia


Dive into the research topics of 'The isthmus characteristics of scar-related macroreentrant atrial tachycardia in patients with and without cardiac surgery'. Together they form a unique fingerprint.

Cite this