BackgroundCatheter ablation (CA) is a highly effective therapy for the treatment of paroxysmal atrial fibrillation (AF) when compared with antiarrhythmic drug therapy (ADT). No randomized studies have compared the two strategies in persistent AF. The present randomized trial aimed to compare the effectiveness of CA vs. ADT in treating persistent AF.Methods and resultsPatients with persistent AF were randomly assigned to CA or ADT (excluding patients with long-standing persistent AF). Primary endpoint at 12-month follow-up was defined as any episode of AF or atrial flutter lasting >24 h that occurred after a 3-month blanking period. Secondary endpoints were any atrial tachyarrhythmia lasting >30 s, hospitalization, and electrical cardioversion. In total, 146 patients were included (aged 55 ± 9 years, 77% male). The ADT group received class Ic (43.8%) or class III drugs (56.3%). In an intention-to-treat analysis, 69 of 98 patients (70.4%) in the CA group and 21 of 48 patients (43.7%) in the ADT group were free of the primary endpoint (P = 0.002), implying an absolute risk difference of 26.6% (95% CI 10.0–43.3) in favour of CA. The proportion of patients free of any recurrence (>30 s) was higher in the CA group than in the ADT group (60.2 vs. 29.2%; P < 0.001) and cardioversion was less frequent (34.7 vs. 50%, respectively; P = 0.018).ConclusionCatheter ablation is superior to medical therapy for the maintenance of sinus rhythm in patients with persistent AF at 12-month follow-up.Clinical Trial Registration InformationNCT00863213 ().

No abstract

No abstract

No abstract

Activation mapping in common atrial flutter has shown circular (reentrant) activation of the right atrium around anatomic structures and areas of functional block. The direction of rotation is counterclockwise (in a frontal view), and in the low right atrium the myocardium between the inferior vena cava (IVC) and the tricuspid valve (TV) is critical to close the activation circle. The circuit can be interrupted by radiofrequency ablation of the myocardium between the TV and the IVC, and, in some cases, by ablation between the coronary sinus and TV. Flutter interruption does not mean complete isthmus ablation, as it may remain inducible, requiring further ablation. Despite attaining noninducibility, flutter may recur, and new procedures may be needed for complete ablation. Atrial fibrillation occurs in up to 30% of the cases during follow-up but is generally well controlled with antiarrhythmic drugs that were ineffective in treating flutter before ablation. Some noncommon atrial flutters show circular right atrial activation in a reversed (clockwise) direction, with the same critical areas in the low right atrium, and in these isthmus ablation is effective. Other noncommon flutters have different substrates in the right or left atrium, and mapping has to define specific critical isthmuses as ablation targets in each case. Left atrial flutter circuits remain inaccessible to ablation.