Frequncy At Coronary Sinus Musculature Predicts The Outcomes Of Persistent Atrial Fibrillation Ablation

BackgroundThe coronary sinus,as a junction of atria,contributes to atrial fibrillation by developing unstable reentry,and isolating atria by ablation at coronary sinus could terminate atrial fibrillation.The present study evaluated whether atrial fibrillation activities at coronary sinus in the subset of patients contributed to atrial fibrillation maintenance and predicted clinical outcome of ablation.MethodsOne hundred twenty-two consecutive patients who had the first time radiofrequency ablation for persistent atrial fibrillation were studied.The bipolar electrograms were obtained from multiple region of left atrium by Lasso mapping catheter before ablation.All 122 consecutive patients received sequential stepwise ablation approach as previously described.After a 3-month blanking period of ablation,patients were reappraised at 3,6,9,and 12 months within one-year,and every 6 months thereafter,up to 3 years.During the follow up,questionnaire,24-hour Holter monitoring,12-lead electrocardiograph were used to evaluate whether patients with symptoms and recurrences.The repeated additional ablation was as same as the index procedure.A successful clinical outcome was defined as the absence of AF and sustains atrial arrhythmia after the last ablation during the follow-up periods.ResultsThe pulmonary vein isolation terminated atrial fibrillation in 12 patients(9.8%).Sequential stepwise ablation was conducted in pulmonary vein isolation non-termination patients and succeeds in 22 patients(18%).In the stepwise termination group,AF frequency in the proximal coronary sinus was significant higher(10.2 ± 2.1 Hz vs.8.3 ± 1.8 Hz,P<0.001),and the ratio of distal coronary sinus to proximal coronary sinus(56.6± 10.11%vs.70.7±9.8%,p<0.001)was significant lower,compared to non-termination group.The stepwise logistical regression analysis indicated the ratio of distal coronary sinus to proximal coronary sinus was an independent predictor with an odds ratio of 1.131(95%CI,1.053-1.214;p=0.001).Within them,there were 43 of 48(90%)patients with the recurrent AF underwent repeat procedures,6 patients conducted the third procedure.The success ratio of the AF patients with CSd/CSp ratio<67%and the ratio>67%were 69%and 48%respectively after the index procedure(p=0.032).A cut off value<67%in ROC curve predicted AF termination with an area under the cure of 0.842(95%confidence interval[CI],0.749-0.936;P<0.001).With a cut-off of 67%,the patients with lower ratio of distal coronary sinus to proximal coronary sinus had significant better index and long-term outcomes than those with higher ratio during follow up of 46±18 months.Conclusions(1)Rapid repetitive activities in the musculature of the proximal coronary sinus may contribute to maintenance of atrial fibrillation after pulmonary vein isolation alone in PeAF.(2)The ratio of distal coronary sinus to proximal coronary sinus might be an independent predictor of termination rate and long-term success rate of catheter ablation in persistent atrial fibrillation.(3)A cutoff of 67%in ratio of distal coronary sinus to proximal coronary sinus might be helpful to identify a subset of persistent atrial fibrillation which is likely prone to terminate with sequential stepwise ablation with coronary sinus ablation.