title: Frequency Gradient Within Coronary Sinus Predicts the Long-Term Outcome of Persistent Atrial Fibrillation Catheter Ablation.
abstract: BACKGROUND
  The coronary sinus (CS), as a junction of the atria, contributes to atrial fibrillation (AF) by developing unstable reentry, and isolating the atria by ablation at the CS could terminate AF. The present study evaluated whether AF activities at the CS in a subset of patients contributed to AF maintenance and predicted clinical outcome of ablation.
  
  
  RESULTS
  We studied 122 consecutive patients who had a first-time radiofrequency ablation for persistent AF. Bipolar electrograms were obtained from multiple regions of the left atrium by a Lasso mapping catheter before ablation. Pulmonary vein isolation terminated AF in 12 patients (9.8%). Sequential stepwise ablation was conducted in pulmonary vein isolation nontermination patients and succeeded in 22 patients (18%). In the stepwise termination group, AF frequency in the proximal CS (CSp) was significantly higher (10.2±2.1 Hz versus 8.3±1.8 Hz,P<0.001), and the ratio of distal CS (CSd) to proximal CS (CSd/CSp ratio, 56.6%±10.11% versus 70.7%±9.8%,P<0.001) was significantly lower than that in the nontermination group. The stepwise logistic regression analysis indicated that the CSd/CSp ratio was an independent predictor with an odds ratio of 1.131 (95%CI 1.053-1.214;P=0.001). With a cutoff of 67%, the patients with lower CSd/CSp ratios had significantly better index and long-term outcomes than those with higher ratios during a follow-up of 46±18 months.
  
  
  CONCLUSIONS
  Rapid repetitive activities in the musculature of the proximal CS may contribute to maintenance of AF after pulmonary vein isolation alone in persistent AF. A cutoff at 67%, of the CSd/CSp frequency ratio might be an indicator to stratify the subset of patients who might benefit from CS ablation.
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Yin
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Ziming
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Lianjun
authors.initials: L
authors.lastname: Gao
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Chang
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Xianjie
authors.initials: X
authors.lastname: Xiao
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Rongfeng
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Texas Heart Institute, Houston, TX.
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Texas Heart Institute, Houston, TX.
authors.forename: Jie
authors.initials: J
authors.lastname: Cheng
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
authors.forename: Yanzong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Texas Heart Institute, Houston, TX yunlong_xia@126.com yxi@texasheart.org.
authors.forename: Yutao
authors.initials: Y
authors.lastname: Xi
authors.affiliation: First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China yunlong_xia@126.com yxi@texasheart.org.
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Xia
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation; D054326:Coronary Sinus / Q000503:physiopathology*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011667:Pulmonary Veins / Q000601:surgery; D016896:Treatment Outcome
keywords: ablation; atrial fibrillation; coronary sinus; pulmonary vein isolation; radiofrequency