Indirect Comparison of Cryoablation and Radiofrequency Ablation as Initial Therapy for Symptomatic Paroxysmal Atrial Fibrillation: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials.

INTRODUCTION: Data on first-line ablation treatment for patients with symptomatic atrial fibrillation (AF) are scarce. This study indirectly compared the efficacy and safety of cryoballoon ablation (CBA) versus radiofrequency ablation (RFA) as initial therapy for symptomatic AF. METHODS: We searched the EMBASE, PubMed, Cochrane Library, and ClinicalTrials.gov databases for randomized controlled trials (RCTs) that compared CBA or RFA with antiarrhythmic drugs (AADs) as first-line treatment for AF from the time of database establishment up to December 2021. The odds ratio (OR) with a 95% confidence interval (CI) was used as a measure of the treatment effect. RESULTS: Six RCTs (3 CBA, 3 RFA) that enrolled a total of 1,215 patients were included in this analysis. There were no significant differences in atrial arrhythmia (AA) (OR 0.993, 95% CI: 0.602-1.638), symptomatic AA (OR 0.638, 95% CI: 0.344-1.182), or serious adverse events (OR 1.474, 95% CI: 0.404-5.376) between the two ablation techniques. The incidences of additional CBA therapy (OR 2.693, 95% CI: 1.277-5.681) and patients who crossed over to AAD therapy (OR 0.345, 95% CI: 0.179-0.664) in the CBA group were significantly lower than those in the RFA group. CONCLUSION: Among patients with paroxysmal AF receiving initial therapy, CBA and RFA share a similar efficacy and safety profile. When pulmonary vein isolation is performed by CBA, study crossover and the need for additional ablation are substantially lower.

Meta-analysis of cryoballoon ablation versus antiarrhythmic drugs as initial therapy for symptomatic atrial fibrillation.

BACKGROUND: The optimal first-line approach for patients with symptomatic atrial fibrillation (AF) remains unclear. We compared the efficacy and safety of cryoballoon ablation (CBA) and antiarrhythmic drugs (AADs) in the initial management of symptomatic AF. HYPOTHESIS: CBA is superior to AAD as initial therapy for symptomatic AF. METHODS: We searched the EMBASE, PubMed, and Cochrane Library databases for randomized controlled trials (RCTs) that compared CBA with AAD as first-line treatment for AF from the date of database establishment until March 18, 2021. The risk ratio (RR) with a 95% confidence interval (CI) was used as a measure of treatment effect. RESULTS: Three RCTs that enrolled 724 patients in total were included in this meta-analysis. Majority of the patients were relatively young and had paroxysmal AF. CBA was associated with a significant reduction in the recurrence of atrial arrhythmia compared with AAD therapy, with low heterogeneity (RR, 0.59; 95% CI, 0.49-0.71; p < .00001; I2  = 0%). There was a significant difference in the rate of symptomatic atrial arrhythmia recurrence (RR, 0.44; 95% CI, 0.29-0.65; p < .0001; I2  = 0%); however, the rate of serious adverse events was similar between the two treatment groups (RR: 1.18; 95% CI: 0.71-1.97, p = .53; I2  = 0%). Transient phrenic nerve palsy occurred in four patients after the CBA procedure. CONCLUSION: The current meta-analysis suggests that CBA is more effective than AAD as initial therapy in patients with symptomatic paroxysmal AF. Serious iatrogenic adverse events are uncommon in CBAs.

Meta-analysis of the safety and efficacy of using minimally interrupted novel oral anticoagulants in patients undergoing catheter ablation for atrial fibrillation.

PURPOSE: The ideal periprocedural anticoagulation strategy for patients being treated with a novel oral anticoagulant (NOAC) during catheter ablation (CA) for atrial fibrillation (AF) is unclear. We evaluated the safety and efficacy of using a minimally interrupted NOAC strategy versus an uninterrupted NOAC or vitamin K antagonist (VKA) strategy during AF ablation. METHODS: The Cochrane Library, PubMed, and EMBASE databases were searched for randomized controlled or prospective observational studies that compared a minimally interrupted NOAC strategy with an uninterrupted NOAC or VKA strategy from the time of database establishment up to December 2019. The primary endpoints were major bleeding, minor bleeding, and symptomatic thromboembolism. The secondary endpoint was silent cerebral infarction (SCI) as detected by post-ablation brain magnetic resonance imaging (MRI). A measurement of treatment effect for the endpoint was reported as pooled odds ratio (OR) with 95% confidence interval (CI). RESULTS: A total of 18 studies (6 randomized, 11 observational, and 1 randomized registry) with 6203 patients were included in the final analysis (47% of the patients received minimally interrupted NOAC). There was no significant difference between treatment groups regarding the risk for major bleeding (OR 1.04, 95% CI 0.69-1.57, P = 0.86, I2 = 27%). Different stratification methods did not yield significant difference regarding the risk for major bleeding. There was no difference between groups regarding the risk for minor bleeding (P = 1.00) or symptomatic thromboembolism (P = 0.26). Brain MRI results showed that both uninterrupted NOAC (OR 0.44, 95% CI 0.23-0.83, P = 0.01, I2 = 72%) and uninterrupted VKA (OR 0.48, 95% CI 0.24-0.97, P = 0.04, I2 = 36%) produced a significant reduction in the rate of SCI when compared with minimally interrupted NOAC. CONCLUSIONS: A periprocedural anticoagulation strategy of minimally interrupted NOAC is not superior to uninterrupted NOAC or VKA when used during AF ablation. There is evidence favoring the use of uninterrupted NOAC or VKA in terms of the risk for SCI.

Meta-analysis of medical management versus catheter ablation for atrial fibrillation.

Several observational studies have shown a survival benefit for patients with atrial fibrillation (AF) who are treated with catheter ablation (CA) rather than medical management (MM). However, data from randomized controlled trials (RCTs) are uncertain. Therefore, we performed a meta-analysis of RCTs that compared the benefits of CA and MM in treatment of AF. We searched the Cochrane Library, PubMed, and EMBASE databases for RCTs that compared AF ablation with MM from the time of database establishment up to January 2020. The risk ratio (RR) with a 95% confidence interval (CI) was used as a measure treatment effect. Twenty-six RCTs that enrolled a total of 5788 patients were included in the meta-analysis. In this meta-analysis, the effect of AF ablation depended on the baseline level of left ventricular ejection fraction (LVEF) in the heart failure (HF) patients. AF ablation appears to be of benefit to patients with a lesser degree of advanced HF and better LVEF by reducing mortality. Meanwhile, this mortality advantage was manifested in long-term follow-up. CA increased the risk for hospitalization when it was used as first-line therapy and decreased the risk when used as second-line therapy. CA reduced recurrence of atrial arrhythmia for different types of AF (paroxysmal or persistent AF) and CA-related complications were non-negligible. There was no convincing evidence for a reduction in long-term stroke risk after AF ablation, and additional high quality RCTs are needed to address that issue.

Peri-procedural novel oral anticoagulants dosing strategy during atrial fibrillation ablation: A meta-analysis.

BACKGROUND: This study aimed at determining whether uninterrupted novel oral anticoagulant (UI-NOAC) would have similar rates of bleeding and thromboembolic events as minimally interrupted NOAC (MI-NOAC) at the time of ablation for atrial fibrillation (AF) as relevant studies are scarce. METHODS: We searched through the PubMed, EMBASE, and Cochrane Library databases for prospective observational studies (POSs) or randomised controlled trials (RCTs) comparing UI-NOAC versus MI-NOAC from their establishment to January 2020. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to compare the pooled treatment effect. RESULTS: Nine studies (three POSs and six RCTs) with 2578 patients were included in the final analysis (55% patients received MI-NOAC). No significant difference was found regarding the risk of major bleeding (OR 0.92, 95% CI 0.43-2.00, P = .84, I2  = 0%). Both groups were comparable in all subgroups ([Asians: OR 1.00, 95% CI 0.43-2.36, P = .99, I2  = 0%], [non-Asians: OR 0.64, 95% CI 0.11-3.88, P = .63, I2  = 0%], [RCTs: OR 0.85, 95% CI 0.37-1.97, P = .71, I2  = 0%], and [POSs: OR 0.52, 95% CI 0.19-12.01, P = .69, I2  = 0%]). The risk of minor bleeding (P = .88) or stroke (P = .69) was comparable between the groups. UI-NOAC resulted in a significant reduction in silent stroke (SS) (OR 0.44, 95% CI 0.23-0.83, P = .01, I2  = 72%). No significant difference was found in SS between once-daily and twice-daily NOACs (OR 0.91, 95% CI 0.63-1.33, P = .64, I2  = 0%) in the MI-NOAC group. CONCLUSIONS: UI-NOAC, as a peri-procedural anticoagulation strategy for catheter ablation in AF, had similar safety compared with MI-NOAC, but was advantageous in terms of SS.