Radiofrequency catheter ablation maintains its efficacy better than antiarrhythmic medication in patients with paroxysmal atrial fibrillation: On-treatment analysis of the randomized controlled MANTRA-PAF trial

Ablation Versus Antiarrhythmic Drugs as First-Line Therapy for Treatment-Naive Atrial Fibrillation: A Systematic Review and Meta-Analysis

Evidence on the relative safety and efficacy of atrial fibrillation catheter ablation and antiarrhythmic drugs (AADs) as the first-line therapy for patients with treatment-naive atrial fibrillation (AF) remains disputed. Digital databases were queried to identify relevant randomized controlled trials. The incidence of recurrent AF, major adverse cardiovascular events, and its components (all-cause death, nonfatal stroke, and bleeding) were compared using the DerSimonian and Laird method under the random-effects model to calculate pooled unadjusted risk ratio (RR) with 95% confidence intervals (CIs). A total of 6 randomized controlled trials consisting of 1,120 patients (574 ablation and 549 AADs) were included in the final analysis. Over a median follow-up of 1 year, the risk of any AF recurrence (RR 0.54, 95% CI 0.39 to 0.75) was significantly lower in patients receiving ablation than in patients receiving AADs. However, there was similar risk of major adverse cardiovascular events (RR 2.65, 95% CI 0.61 to 11.46), trial-defined composite end point of adverse events (RR 0.71, 95% CI 0.28 to 1.80), stroke (RR 2.42, 95% CI 0.22 to 26.51), all-cause mortality (RR 1.98, 95% CI 0.28 to 13.90), and procedure/medication failure (RR 2.65, 95% CI 0.61 to 11.46) with both therapies. In conclusion, in patients presenting with treatment-naive AF, ablation as a first-line therapy lowers the risk of AF recurrence with no associated increase in major adverse events, stroke, and mortality compared with AADs.

Improvement in Quality of Life via Catheter Ablation for Atrial Fibrillation in Patients Undergoing Hemodialysis Therapy

Background

Methods

Results

Conclusions

Comparison of the Efficacy and Safety Endpoints of Five Therapies for Atrial Fibrillation: A Network Meta-Analysis

Introduction

Atrial fibrillation (AF) is a prevalent arrhythmia that occurs in 2–4% of adults and poses a threat to human health. Thus, comparison of the efficacy and safety of therapies for AF is warranted. Here, we used network analysis to compare efficacy (arrhythmia recurrence and re-hospitalization) and safety (ischemic cerebral vascular events, all-cause mortality, and cardiovascular mortality) endpoints among five major therapies for AF.

Methods

The PubMed, Cochrane, and Embase databases were searched, and relevant literature was retrieved. Only studies that made comparisons among the therapies of interest and involved patients with AF were included. Pairwise comparisons and frequentist method (SUCRA plot) analyses were conducted.

Results

In total, 62 studies were included in the pooled analysis. In pairwise comparisons, atrioventricular nodal ablation plus permanent pacemaker (AVN + PPM) was associated with a significantly higher risk of atrial arrhythmia recurrence than surgical ablation [odds ratio (OR): 23.82, 95% confidence interval (CI): 1.97–287.59, fixed-effect model; 3.82, 95% CI: 1.01–559.74, random-effects model]. Furthermore, radiofrequency ablation was associated with a significantly lower risk of cardiovascular mortality than medication in pairwise comparison (OR: 0.49, 95% CI: 0.29–0.83, fixed-effect model; OR: 0.49, 95% CI: 0.27–0.9, random-effects model). Frequentist analysis indicated that AVN + PPM had the best performance in reducing the risk of safety and efficacy endpoints.

Conclusion

Non-pharmaceutical therapies showed superior performance to traditional drug therapy in lowering the risk of safety and efficiency endpoint events. AVN + PPM performed best in reducing the risk of safety and efficacy endpoints.

Catheter ablation for atrial fibrillation: impact on mortality, morbidity, quality of life, and implications for the future

Despite the advances in technologies and techniques in the field of catheter ablation for cardiac arrhythmias, it is estimated that the prevalence of atrial fibrillation (AF) will further increase in the nearest future. The latest trials have proven the beneficial effect on mortality after pulmonary vein isolation in patients with impaired left ventricular function, while no such effect has been seen in patients without left ventricular dysfunction. This raises the question of whether catheter ablation for AF is still suited for the latter patient cohort or whether the endpoint of mortality is not adequate enough. Not only does pulmonary vein isolation reduce the burden of atrial fibrillation, but it also somehow alters the patients’ perception of it in the case of recurrence. Independent of the presence of ventricular dysfunction, patients experience a relief of AF-related symptoms, which is accompanied by an increase in quality of life based on the available patient-reported outcome measures, despite AF recurrence. Trials that are currently recruiting patients seek to unveil the accountable circumstances for these remaining uncertainties and help expand our understanding of a procedure that has been routinely performed for two decades.

Catheter ablation of atrial fibrillation in Korea: results from the Korean Heart Rhythm Society Ablation Registry for Atrial Fibrillation (KARA)

Background

This study aims to investigate the current status of AF (atrial fibrillation) catheter ablation in Korea.

Methods

The patients who underwent AF catheter ablation from September 2017 to December 2019 were prospectively enrolled from 37 arrhythmia centers. Demographic data, procedural characteristics, the extent of catheter ablation, acute success of the ablation lesion set, rate and independent risk factor for recurrence of AF were analyzed.

Results

A total of 2402 AF patients [paroxysmal AF (PAF) 45.7%, persistent AF (PeAF) 43.1% and redo AF 11.2%] were included. Pulmonary vein isolation (PVI) was performed in 2378 patients (99%) and acute success rate was 97.9%. Additional non-PV ablation (NPVA) were performed in 1648 patients (68.6%). Post-procedural complication rate was 2.2%. One-year AF-free survival rate was 78.6% and the PeAF patients showed poorer survival rate than the ones with other types (PeAF 72.4%, PAF 84.2%, redo AF 80.0%). Additional NPVA did not influence the recurrence of AF in the PAF patients (PVI 17.0% vs. NPVA 14.6%, P value 0.302). However, it showed lower AF recurrence rate in the PeAF patients (PVI 34.9% vs. NPVA 24.4%, P value 0.001). Valvular heart disease, left atrial diameter, PeAF, PVI alone, need of NPVA for terminating AF, and failed ablation were independent predictors of AF recurrence.

Conclusions

Additional NPVA was associated better rhythm outcome in the patients with PeAF, not in the ones with PAF. The independent risk factors for AF recurrence in Korean population were similar to previous studies. Further research is needed to discover optimal AF ablation strategy.

Cycle Length Evaluation in Persistent Atrial Fibrillation Using Kernel Density Estimation to Identify Transient and Stable Rapid Atrial Activity

Purpose

Left atrial (LA) rapid AF activity has been shown to co-localise with areas of successful atrial fibrillation termination by catheter ablation. We describe a technique that identifies rapid and regular activity.

Methods

Eight-second AF electrograms were recorded from LA regions during ablation for psAF. Local activation was annotated manually on bipolar signals and where these were of poor quality, we inspected unipolar signals. Dominant cycle length (DCL) was calculated from annotation pairs representing a single activation interval, using a probability density function (PDF) with kernel density estimation. Cumulative annotation duration compared to total segment length defined electrogram quality. DCL results were compared to dominant frequency (DF) and averaging.

Results

In total 507 8 s AF segments were analysed from 7 patients. Spearman’s correlation coefficient was 0.758 between independent annotators (P < 0.001), 0.837–0.94 between 8 s and ≥ 4 s segments (P < 0.001), 0.541 between DCL and DF (P < 0.001), and 0.79 between DCL and averaging (P < 0.001). Poorer segment organization gave greater errors between DCL and DF.

Conclusion

DCL identifies rapid atrial activity that may represent psAF drivers. This study uses DCL as a tool to evaluate the dynamic, patient specific properties of psAF by identifying rapid and regular activity. If automated, this technique could rapidly identify areas for ablation in psAF.

Long-term observation of catheter ablation vs. pharmacotherapy in the management of persistent and long-standing persistent atrial fibrillation (CAPA study)

AIMS

The roles of radiofrequency catheter ablation (RFCA) and pharmacotherapy in treating persistent and long-standing persistent atrial fibrillation (AF) have not been sufficiently investigated. We conducted a multicentre, randomized, controlled trial to compare the effects of RFCA and pharmacotherapy on the prognosis of these patients.

METHODS AND RESULTS

A total of 648 patients with persistent and long-standing persistent AF were enrolled from 30 centres and randomized to either the ablation group (n = 327) or the pharmacotherapy group (n = 321). After 54.2 ± 10.6 months of follow-up, the primary endpoints occurred significantly more rarely in the ablation group than in the pharmacotherapy group (10.4% vs. 17.4%; hazard ratio 0.59, 95% confidence interval 0.48-0.75; P < 0.001). The incidence of stroke/transient ischaemic attack (TIA) was significantly lower in the ablation group (4.2% vs. 7.2%, P < 0.001). Likewise, the incidence of new-onset congestive heart failure (CHF) was lower in the ablation group (2.8% vs. 7.2%, P < 0.001). More patients had sinus rhythm in the ablation group than in the pharmacotherapy group (60.6% vs. 20.9%, P < 0.001), but fewer patients were on antiarrhythmic drugs (24.4% vs. 41.6%, P < 0.001) and warfarin (60.8% vs. 83.9%, P = 0.001). Both the 6-min walk distance and the quality of life (QoL) were improved in the ablation group at the end of follow-up.

CONCLUSION

In patients with persistent and long-standing persistent AF, RFCA-based treatment was superior to pharmacotherapy in decreasing stroke/TIA and new-onset CHF and improving QoL.

Long-Term Outcomes and Improvements in Quality of Life in Patients with Atrial Fibrillation Treated with Catheter Ablation vs. Antiarrhythmic Drugs

BACKGROUND

Catheter ablation (CA) is a recognized first-line treatment for atrial fibrillation (AF) in selected patients; however, the differences between CA and antiarrhythmic drugs (AADs) in terms of long-term outcomes and quality of life (QoL) have not often been compared.

OBJECTIVES

We performed a meta-analysis of randomized controlled trials (RCTs) to compare long-term outcomes and QoL with CA and AADs in the treatment of AF.

METHODS

We searched the MEDLINE database for English-language RCTs of CA or AADs in AF from 1 January 2005 to 30 October 2019 with no other restrictions. We included studies that reported sample sizes and the long-term outcomes of interest as well as sample size, mean ± standard deviation or 95% confidence intervals (CIs) for QoL outcomes with CA and AADs.

RESULTS

We identified 20 RCTs involving 5425 participants. Compared with patients who received only AADs, patients receiving CA had a significantly decreased risk of all-cause death (relative risk [RR] 0.72; 95% CI 0.58-0.90) and cardiovascular hospitalization (RR 0.85; 95% CI 0.79-0.91). We found a significant increase in the risk of cardiac tamponade (RR 5.86; 95% CI 1.77-19.44) but no difference in the risk of heart failure, stroke or transient ischemic attack, atrial tachycardia, bleeding or hematoma, and pulmonary vein stenosis. For long-term QoL after treatment, both therapies resulted in improved scores on the Medical Outcomes Study 36-Item Short Form Survey (SF-36): weighted mean differences (WMDs) for the physical component score (PCS) were 5.89 for CA and 4.26 for AADs and for the mental component score (MCS) were 7.12 for CA and 5.06 for AADs. At the end of follow-up, groups receiving CA had significantly higher scores in both areas. The change in PCS and MCS between baseline and end of follow-up was also significantly higher in the CA groups: WMD 1.51 for change in PCS and 1.49 for change in MCS. All eight SF-36 subscale scores improved for patients receiving CA, whereas patients receiving AADs recorded no improvement in the general health and bodily pain subscales. At the end of follow-up, CA groups had significantly higher scores than AAD groups in the following subscales: physical functioning, role limitations due to physical health problems, bodily pain, general health, vitality, and role limitations due to emotional problems.

CONCLUSIONS

In the treatment of AF, CA appeared to be superior to AADs, decreasing the risk of all-cause death and cardiovascular hospitalization and improving the long-term QoL of patients with AF. CA was better tolerated and more effective than pharmacological therapy and allowed for improved QoL.

Comparison of the efficacy and safety of different doses of nifekalant in the instant cardioversion of persistent atrial fibrillation during radiofrequency ablation

Nifekalant has been used in the treatment of atrial arrhythmia recently. However, there is no consensus on the preferable nifekalant dose to treat atrial fibrillation (AF). The purpose of this study was to explore efficacy and safety of different doses of nifekalant in the cardioversion of persistent AF. The study was a single-centre, randomized controlled trial. All subjects received nifekalant or placebo intravenously, and the nifekalant was given at the dosage of 0.3, 0.4 or 0.5 mg/kg. Primary efficacy end-point: compared with 0.3 mg group, the rate of cardioversion to sinus rhythm from AF in 0.4 and 0.5 mg group was higher. The 0.4 and 0.5 mg/kg doses were associated with a similar magnitude of efficacy (P > .05). Secondary efficacy end-point: termination rates of AF in the group of 0.4 mg and 0.5 mg were higher than 0.3 mg. Primary safety end-point: the rate of Torsades de Pointes or ventricular fibrillation was numerically lower in the 0.4 mg group than 0.5 mg group (P = .02). Secondary safety end-point: The rates of the majority of other common drug-related adverse events in the group of 0.5 and 0.4 mg were higher than the 0.3 mg group. A 0.4 mg/kg dose of intravenous nifekalant may be recommended during the radiofrequency ablation for persistent AF considering the benefit-risk profile.

Catheter Ablation vs. Medical Treatment in Patients With Atrial Fibrillation

Atrial fibrillation has become the most commonly seen cardiac arrhythmia in clinical practice affecting almost 5.6 million Americans with that number expected to rise in the near future. The current literature review is aimed to assess the efficacy of catheter ablation in the treatment of patients with atrial fibrillation when compared to standard medical therapy. A PubMed search for studies of "Atrial Fibrillation" found 83,251 articles. Following the application of inclusion/exclusion criteria, we identified 44 articles of relevance that compared catheter ablation and medical therapy in the treatment of atrial fibrillation. These 44 articles included 20 Observational studies, eight randomized clinical trials, three clinical trials, five cohort studies, and eight review articles. Our review determined that catheter ablation was associated with a much lower rate of reoccurrence of atrial fibrillation when compared to medical therapy, as well as decreased cardiovascular outpatient visits and thromboembolic complications. The effect of quality on life when compared to medical treatment, however, was found to be inconclusive.

Opposite effect of ablation on early/late-phase thromboembolic incidence in patients with atrial fibrillation: A meta-analysis on more than 100 000 individuals

Background

Atrial fibrillation (AF) is an important risk factor for thromboembolic events, for which catheter ablation represents an effective therapy for rhythm control. Intuitively, ablation may reduce the incidence of thromboembolism, but data is quite limited.

Hypothesis

Catheter ablation was associated with the fewer risk of thromboembolism compared with nonablation in patients with AF.

Methods

A systematic search was performed in PubMed, EMBASE, the Web of Science, and the Cochrane Library from inception to September 2019. Random‐effects model was used to estimate the risk ratios (RR) for the thromboembolic events between the ablation and nonablation groups.

Results

Twenty‐five studies (12 randomized controlled trials and 13 observational studies) with 104 687 participants were included. Pooled analysis suggested that ablation was associated with a 35% lower risk of total thromboembolic events compared to nonablation group (RR = 0.65; 95% CI, 0.51‐0.82; P = .0003). When separated into early‐phase (<30 days) and late‐phase (>30 days) events, ablation was associated with an increased early‐phase thromboembolism (RR = 1.96; 95% CI, 1.35‐2.83; P = .0004) but a decreased late‐phase thromboembolism (RR = 0.75; 95% CI, 0.63‐0.90; P = .002). Subgroup analysis according to different study types found similar results were found in observation studies, but not in RCT studies because the sample size was too small to be conclusive.

Conclusions

In patients with AF, catheter ablation was associated with a fewer risk of overall and late‐phase thromboembolism in comparison with nonablation. However, over the early postoperative period, catheter ablation was associated with the double higher risk of thromboembolic events.

The Impact of Advances in Atrial Fibrillation Ablation Devices on the Incidence and Prevention of Complications

The number of patients with atrial fibrillation currently referred for catheter ablation is increasing. However, the number of trained operators and the capacity of many electrophysiology labs are limited. Accordingly, a steeper learning curve and technical advances for efficient and safe ablation are desirable. During the last decades several catheter-based ablation devices have been developed and adapted to improve not only lesion durability, but also safety profiles, to shorten procedure time and to reduce radiation exposure. The goal of this review is to summarise the reported incidence of complications, considering device-related specific aspects for point-by-point, multi-electrode and balloon-based devices for pulmonary vein isolation. Recent technical and procedural developments aimed at reducing procedural risks and complications rates will be reviewed. In addition, the impact of technical advances on procedural outcome, procedural length and radiation exposure will be discussed.

Combined Cryoballoon and Radiofrequency Ablation Versus Radiofrequency Ablation Alone for Long-Standing Persistent Atrial Fibrillation

BACKGROUND

To achieve sinus rhythm, ablation of long-standing persistent atrial fibrillation (LSPAF) usually requires substrate modification in addition to pulmonary vein isolation (PVI). In the present article, we aimed to compare clinical and substrate modification effects of 2 distinct PVI strategies during stepwise ablation in patients with LSPAF: (1) Combined approach: cryoballoon (CB) for PVI and radiofrequency (RF) ablation for substrate modification and (2) RF-only approach: RF ablation for both PVI and substrate modification.

MATERIALS AND METHODS

A total of 34 patients were divided into 2 groups: 19 in the combined group and 15 in the RF group. Left atrial (LA) complex fractionated atrial electrogram (CFAE) maps were acquired before and after PVI and compared between groups. The groups were compared for acute atrial fibrillation termination (AFT) rates and long-term arrhythmia-free survival.

RESULTS

A significant reduction on total LA CFAE area was observed with PVI in both groups. In the CB group, when pulmonary veins were excluded, the reduction of LA CFAE area was the most significant on the posterior wall of left atrium and which was greater than in the RF group. Although the ratio of AFT was higher in the CB group (44% versus 33%, respectively), single-procedure arrhythmia-free survival at 1 year was comparable between groups (68% in the CB group versus 66% in the RF group). Times of total procedure, fluoroscopy and post-PVI RF were all shorter in the CB group.

CONCLUSIONS

CB may cause greater substrate modification on the posterior wall and increase AFT rate during LSPAF ablation.

Who Needs Catheter Ablation And Which Approach?

Catheter ablation therapy for atrial fibrillation (AF) has gained a significant role during maintenance of sinus rhythm compared to anti-arrhythmic medication. Catheter ablation techniques are also improved and progressed over years in parallel to better understanding of disease mechanisms and technological advancements. However, due to invasive nature of the therapy with its pertinent procedural risks, both appropriate patient selection and use of relevant approach should be considered by all electrophysiologists before decide to perform catheter ablation.

Efficacy and safety of ablation for people with non-paroxysmal atrial fibrillation

BACKGROUND

The optimal rhythm management strategy for people with non-paroxysmal (persistent or long-standing persistent) atrial fibrilation is currently not well defined. Antiarrhythmic drugs have been the mainstay of therapy. But recently, in people who have not responded to antiarrhythmic drugs, the use of ablation (catheter and surgical) has emerged as an alternative to maintain sinus rhythm to avoid long-term atrial fibrillation complications. However, evidence from randomised trials about the efficacy and safety of ablation in non-paroxysmal atrial fibrillation is limited.

OBJECTIVES

To determine the efficacy and safety of ablation (catheter and surgical) in people with non-paroxysmal (persistent or long-standing persistent) atrial fibrillation compared to antiarrhythmic drugs.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, Embase Ovid, conference abstracts, clinical trial registries, and Health Technology Assessment Database. We searched these databases from their inception to 1 April 2016. We used no language restrictions.

SELECTION CRITERIA

We included randomised trials evaluating the effect of radiofrequency catheter ablation (RFCA) or surgical ablation compared with antiarrhythmic drugs in adults with non-paroxysmal atrial fibrillation, regardless of any concomitant underlying heart disease, with at least 12 months of follow-up.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies and extracted data. We evaluated risk of bias using the Cochrane 'Risk of bias' tool. We calculated risk ratios (RRs) for dichotomous data with 95% confidence intervals (CIs) a using fixed-effect model when heterogeneity was low (I² <= 40%) and a random-effects model when heterogeneity was moderate or substantial (I² > 40%). Using the GRADE approach, we evaluated the quality of the evidence and used the GRADE profiler (GRADEpro) to import data from Review Manager 5 to create 'Summary of findings' tables.

MAIN RESULTS

We included three randomised trials with 261 participants (mean age: 60 years) comparing RFCA (159 participants) to antiarrhythmic drugs (102) for non-paroxysmal atrial fibrillation. We generally assessed the included studies as having low or unclear risk of bias across multiple domains, with reported outcomes generally lacking precision due to low event rates. Evidence showed that RFCA was superior to antiarrhythmic drugs in achieving freedom from atrial arrhythmias (RR 1.84, 95% CI 1.17 to 2.88; 3 studies, 261 participants; low-quality evidence), reducing the need for cardioversion (RR 0.62, 95% CI 0.47 to 0.82; 3 studies, 261 participants; moderate-quality evidence), and reducing cardiac-related hospitalisation (RR 0.27, 95% CI 0.10 to 0.72; 2 studies, 216 participants; low-quality evidence) at 12 months follow-up. There was substantial uncertainty surrounding the effect of RFCA regarding significant bradycardia (or need for a pacemaker) (RR 0.20, 95% CI 0.02 to 1.63; 3 studies, 261 participants; low-quality evidence), periprocedural complications, and other safety outcomes (RR 0.94, 95% CI 0.16 to 5.68; 3 studies, 261 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

In people with non-paroxysmal atrial fibrillation, evidence suggests a superiority of RFCA to antiarrhythmic drugs in achieving freedom from atrial arrhythmias, reducing the need for cardioversion, and reducing cardiac-related hospitalisations. There was uncertainty surrounding the effect of RFCA with significant bradycardia (or need for a pacemaker), periprocedural complications, and other safety outcomes. Evidence should be interpreted with caution, as event rates were low and quality of evidence ranged from moderate to very low.

Antiarrhythmic Drug Therapy for Rhythm Control in Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and affects over 33 million people worldwide. AF is associated with stroke and systemic thromboembolism, unpleasant symptoms and reduced quality of life, heart failure, and increased mortality, and treatment of AF and its complications are associated with significant cost. Antiarrhythmic drugs (AADs) can suppress AF, allowing long-term maintenance of sinus rhythm, and have the potential to relieve symptoms and reverse or prevent adverse effects associated with AF. However, large randomized controlled studies evaluating use of AADs have not demonstrated a clear benefit to maintaining sinus rhythm, and AADs often have significant limitations, including a modest rate of overall success at maintaining sinus rhythm, frequent side effects, and potentially life-threatening toxicities. Although some of the currently available AADs have been available for almost 100 years, better tolerated and more efficacious AADs have recently been developed both for long-term maintenance of sinus rhythm and for chemical cardioversion of AF to sinus rhythm. Advances in automated AF detection with cardiac implantable electronic devices have suggested that AADs might be useful for suppressing AF to allow safe discontinuation of anticoagulation in select patients who are in sinus rhythm for prolonged periods of time. AADs may also have synergistic effects with catheter ablation of AF. This review summarizes the pharmacology and clinical use of currently available AADs for treatment of AF and discusses novel AADs and future directions for rhythm control in AF.

Collateral findings during computed tomography scan for atrial fibrillation ablation: Let’s take a look around

The growing number of atrial fibrillation catheter ablation procedures warranted the development of advanced cardiac mapping techniques, such as image integration between electroanatomical map and cardiac computed tomography. While scanning the chest before catheter ablation, it is frequent to detect cardiac and extracardiac collateral findings. Most collateral findings are promptly recognized as benign and do not require further attention. However, sometimes clinically relevant collateral findings are detected, which often warrant extra diagnostic examinations or even invasive procedure, and sometimes need to be followed-up over time. Even though reporting and further investigating collateral findings has not shown a clear survival benefit, almost all the working groups providing data on collateral findings reported some collateral findings eventually coming out to be malignancies, sometimes at an early stage. Therefore, there is currently no clear agreement about the right strategy to be followed.