Single ring isolation for atrial fibrillation ablation: Impact of the learning curve

Abstract

Introduction: Although single ring isolation is an accepted strategy for undertaking pulmonary vein (PV) and posterior wall isolation (PWI) during atrial fibrillation (AF) ablation, the learning curve associated with this technique as well as procedural and clinical success rates have not been widely reported.Methods and Results: Prospectively collected data from 250 consecutive patients undergoing de novo AF ablation using single ring isolation. PWI was achieved in 212 patients (84.8%) and PV isolation without PWI was achieved in 37 patients (14.4%).Thirty-one cases (12.4%) demonstrated inferior line sparing where PWI was achieved without a continuous posterior wall inferior line. A learning curve was observed, with higher rates of PWI (98% last 50 vs. 82% first 50 cases, p = .016), higher rates of inferior line sparing (20% last 50 vs. 8% first 50 cases, p = .071) and lower ablation times (43.8 min (interquartile range [IQR]: 34.6-57.0 min) last 50 versus. 96.5 min (IQR: 80.8-115.8 min) first 50 cases; p < .001). Three (1.3%) major procedure-related complications were observed. Twelve-month, single-procedure freedom from atrial arrhythmia without drugs was 70.5% (95% confidence interval[CI]: 61.5%-77.7%) and 60.0% (95% CI: 50.2%-68.4%) for paroxysmal and persistent/longstanding persistent AF. Twelve-month multi-procedure freedom from atrial arrhythmia was 92.2% (95%CI: 85.6%-95.9%) and 85.6% (95%CI: 77.2%-91.0%) for paroxysmal and persistent/longstanding persistent AF. Conclusion:Employing a single ring isolation approach, PWI can be achieved in most cases. There is a substantial learning curve with higher rates of PWI, reduced

Left-sided atrial tachycardia ablation in an atrial-esophageal fistula survivor

“…However, if the PVs would have been reconnected, a more distal reisolation of the PVs or a single ring isolation with inferior line sparing could have been a bail-out option. 10 , 11 We identified a gap in the roof line and the posterior wall could be reisolated by RF ablation anterior to the initial roof line to avoid ablation on the posterior wall. The clinical arrhythmias in this patient were a left-sided focal AT and a macroreentrant AT around the mitral valve.…”

Single ring isolation of pulmonary veins combined with electrical isolation of the superior vena cava in patients with paroxysmal atrial fibrillation

“…Some previous studies reported the ablation technique of SRI for paroxysmal and persistent AF ( 6 , 16 ) and that SRI could improve the success rate ( 7 , 17 ). However, it also had the following disadvantages: the single-ring ablation line was relatively long and it was difficult to isolate the PVs at the initial ablation attempt.…”

“…ectopic beats initiating PAF should also be taken into account, especially the left atrial posterior wall (LAPW) (5). Previous studies reported that single-ring isolation (SRI) for paroxysmal and persistent AF and long-term freedom from arrhythmia were comparable to other AF ablation techniques (6)(7)(8). In addition, the superior vena cava (SVC) has been shown as one of the most important sites of non-PV AF triggers, and SVC isolation (SVCI), in addition to PV isolation, reduces the recurrence of AF (9)(10)(11)(12)(13).…”

Single ring isolation is superior to circumferential pulmonary vein isolation plus modified posterior box isolation with a high power of 40-45 W in patients with persistent atrial fibrillation

“…Previous studies have demonstrated that SRI plays an important role in decreasing the ablation time 19,20 .…”

“…Single ring isolation (SRI) is carried out based on physiological principles to electrically isolate the posterior left atrium and pulmonary veins. This approach limits the amount of ablation in the posterior left atrium, shortens the ablation time and has the potential to reduce collateral damage to the oesophagus, preventing the formation of atrial oesophageal stula 19,20 . On the other hand, a prior study revealed that the recurrence of atrial brillation is common after SRI.…”