Catheter versus surgical ablation of atrial fibrillation after a failed initial pulmonary vein isolation procedure: a randomized controlled trial.

INTRODUCTION: The aim of this prospective randomized study was to compare the efficacy and safety of catheter ablation (CA) versus surgical ablation (SA) in the treatment of paroxysmal and persistent AF after failed initial pulmonary vein isolation procedure. METHODS AND RESULTS: Patients with a history of symptomatic AF after a previous failed first ablation procedure were eligible for this study. Patients were randomized to CA (n = 32) or SA (n = 32) redo ablation. The primary endpoint was recurrence of atrial tachyarrhythmia at 1 year of follow-up. At the 12-month follow-up, 26 (81%) of the 32 SA group patients and 15 (47%) of the 32 CA group were AF/AT-free on no antiarrhythmic drugs (P = 0.004, log-rank test). In patients with PAF, 17 (85%) patients of the 20 in SA group and 10 (56%) patients of the 18 in CA group were AF-free (P = 0.04, log-rank test). In patients with PersAF, 9 (75%) patients of the 12 in SA group and 5 (36%) patients of the 14 in CA group were AF-free (P = 0.04, log-rank test). The number of the serious adverse event in the SA group was significantly higher (1 CA group vs 7 SA group; P = 0.02). CONCLUSION: In patients with PAF and PersAF after failed initial CA, SA is superior to CA for maintenance of sinus rhythm, although serious adverse event rate is significantly higher for SA.

Progression of atrial fibrillation after a failed initial ablation procedure in patients with paroxysmal atrial fibrillation: a randomized comparison of drug therapy versus reablation.

BACKGROUND: The aim of this prospective randomized study was to assess whether an early reablation was superior to antiarrhythmic drug (AAD) therapy in patients with previous failed pulmonary vein isolation. METHODS AND RESULTS: Patients with paroxysmal atrial fibrillation (AF) eligible for AAD therapy or reablation after a previously failed initial pulmonary vein isolation procedure were eligible for this study and were followed up for 3 years to assess rhythm by means of an implanted cardiac monitor. After the blanking period postablation, 154 patients had symptomatic AF recurrences and were randomized to AAD (n=77) or repulmonary vein isolation (n=77). At the end of follow-up, 61 (79%) patients in the AAD group and 19 (25%) patients in the reablation group demonstrated AF% progression (P<0.01). The AF% at 36 months was significantly greater in the AAD group compared with patients in the reablation group (18.8±11.4% versus 5.6±9.5%, respectively; P<0.01). In addition, 18 (23%) patients in the AAD group and 3 (4%) patients in the reablation group progressed to persistent AF (P<0.01). Furthermore, 45 (58%) of the 77 reablation group patients were free of AF/atrial tachycardia on no AADs; in contrast, in the AAD group, only 9 (12%) of the 77 patients were free of AF/atrial tachycardia (P<0.01) throughout follow-up. CONCLUSIONS: Redo AF ablation was substantially more effective than AAD in reducing the progression and prevalence of AF after the failure of an initial ablation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01709682.

Cryoballoon versus radiofrequency for pulmonary vein re-isolation after a failed initial ablation procedure in patients with paroxysmal atrial fibrillation.

AIM: Catheter ablation of paroxysmal atrial fibrillation (PAF) is associated with an important risk of early and late recurrence, necessitating repeat ablation procedures. The aim of this prospective randomized patient-blind study was to compare the efficacy and safety of cryoballoon (Cryo) versus radiofrequency (RF) ablation of PAF after failed initial RF ablation procedure. METHODS: Patients with a history of symptomatic PAF after a previous failed first RF ablation procedure were eligible for this study. Patients were randomized to Cryo or RF redo ablation. The primary endpoint of the study was recurrence of atrial tachyarrhythmia, including AF and left atrial flutter/tachycardia, after a second ablation procedure at 1 year of follow-up. All patients were implanted with a cardiac monitor (Reveal XT, Medtronic) to continuously track the cardiac rhythm. Patients with an AF burden (AF%) ≤ 0.5% were considered AF-free (Responders), while those with an AF% > 0.5% were classified as patients with AF recurrences (non-Responders). RESULTS: Eighty patients with AF recurrences after a first RF pulmonary vein isolation (PVI) were randomized to Cryo (N = 40) or to RF (N = 40). Electrical potentials were recorded in 77 mapped PVs (1.9 ± 0.8 per patient) in Cryo Group and 72 PVs (1.7 ± 0.8 per patient) in RF Group (P = 0.62), all of which were targeted. In Cryo group, 68 (88%) of the 77 PVs were re-isolated using only Cryo technique; the remaining 9 PVs were re-isolated using RF. In RF group, all 72 PVs were successfully re-isolated (P = 0.003 vs Cryo). By intention-to-treat, 23 (58%) RF patients were AF-free vs 17 (43%) Cryo patients on no antiarrhythmic drugs at 1 year (P = 0.06). Three patients had temporary phrenic nerve paralysis in the Cryo group; the RF group had no complications. Of the 29 patients who had only Cryo PVI without any RF ablation, 11 (38%) were AF-free vs 20 (59%) of the 34 patients who had RF only (P = 0.021). CONCLUSION: When patients require a redo pulmonary vein isolation ablation procedure for recurrent PAF, RF appears to be the preferred energy source relative to Cryo.

Does atrial fibrillation burden measured by continuous monitoring during the blanking period predict the response to ablation at 12-month follow-up?

BACKGROUND: Recurrences are common within the first months following atrial fibrillation (AF) ablation. However, prior studies using only intermittent ECG recording have not shown a powerful correlation with ultimate response. OBJECTIVE: The purpose of this study was to use continuous AF monitoring with an implanted monitor to assess the AF burden measured continuously during the first months postablation and the relationship to subsequent AF recurrences. METHODS: Six hundred thirteen patients with symptomatic drug-refractory AF (17% with persistent AF) were part of this retrospective analysis. All patients underwent circumferential pulmonary vein isolation and were implanted with a subcutaneous AF monitor (Reveal XT, Medtronic) for collecting data on AF burden (AF%) during a 12-month follow-up period. AF freedom (responders) was defined as AF% ≤0.5% during each monthly telemetric follow-up. A receiver operating characteristic curve analysis was performed to identify the value in AF% during the first months in the postablation blanking period that was predictive of later recurrence of AF. Sensitivity of 90% was selected as the target value. RESULTS: After the first ablation procedure, 396 of the 613 patients (65%) were responders (AF ≤0.5%) at 12 months: 346 of 508 (68%) in the paroxysmal AF group and 50 of 105 (47%) in the persistent AF group. Using the receiver operating characteristic curve, the specificity corresponding to 90% sensitivity was 85% for AF% at 2 months. The corresponding threshold in the AF burden during the blanking period able to identify patients at risk for late recurrences was 4.5%, corresponding to a cumulative 65.9 hours (2.75 days) spent in AF during the first 2 months. In a multivariate analysis, AF% <4.5% during the first 2 months was highly significant (P <.001), and the odds ratio of responders/nonresponders was 39.8 (95% CI, 19.1-82.9). CONCLUSION: The AF burden measured during the blanking period can predict the response to catheter ablation at 12 months. AF% ≥4.5% at 2 months assessed by continuous monitoring is a powerful predictor of subsequent AF recurrences after initial ablation, thus providing relevant clinical information to select patients for early reintervention.