Catheter Ablation Versus Antiarrhythmic Drugs for Atrial Fibrillation

Global research productions pertaining to atrial fibrillation from 2004 to 2018: A bibliometric analysis

BACKGROUND

We analyzed the scientific outputs of global atrial fibrillation (AF) researches, developed a model to qualitatively and quantitatively evaluate the AF research productions from 2004 to 2018.

METHODS

The data was retrieved from the Web of Science Core Collection (WOSCC) on June 15, 2019. Bibliometrics tools-CiteSpace V (Drexel university, Chaomei Chen) and VOSviewer (Leiden University, van Eck NJ) --were used for bibliometric analyzing published outputs and finding research hotspots.

RESULTS

There were a total of 21,839 research articles on AF, and the annual publication rate increased over time from 2004 to 2018. The Journal of Cardiovascular Electrophysiology published the greatest number of articles, and the leading country was the United States. The leading institution was the Mayo Clinic, and the most productive researchers were: LIP GYH, Natale A, Chen SA, DI Biase L, and Kuck KH. The keywords analysis showed that catheter ablation, risk, heart failure, stroke, and management were research hotspots.

CONCLUSION

Bibliometric analysis of the literature shows that research on AF continues to be a hot spot, and the clinical treatment of AF is an important research frontier. However, further research and collaboration are needed worldwide. Our findings aim to provide valuable information for the editors of journals that publish research on arrhythmia, and to help researchers identify new perspectives for future researches.

Ablation Versus Medical Therapy for Atrial Fibrillation in the Elderly: A Propensity Score-Matched Comparison

Background

Whether ablation therapy reduces the risk of death and embolic events in elderly patients with atrial fibrillation (AF) remains unclear.

Material/Methods

AF patients ≥65 years old receiving either catheter ablation or non-ablation therapy at 2 tertiary and 2 non-tertiary hospitals in Beijing from November 2009 to December 2012 were enrolled. Patients were followed up every 6 months for information on treatment and clinical event occurrence. A propensity score matching algorithm produced comparable 2 groups of patients treated with ablation or non-ablation. Rates of a composite of all-cause death, non-fatal stroke, and peripheral embolism were the primary outcomes. Each composite component and major bleeding were the secondary outcomes.

Results

There were 596 ablated patients and 1144 patients with non-ablation therapy enrolled. Propensity score algorithm matched 347 comparable pairs of patients. Patient characteristics variables were well balanced. During 523.5 and 497.5 patient-years follow-up, respectively, ablation therapy was associated with a significant lower risk of experiencing the primary composite outcome (hazard ratio [HR]=0.40; 95% confidence interval [CI]: 0.19–0.85), all-cause death (HR=0.13 95% CI: 0.04–0.43), and major bleeding (HR=0.23; 95% CI: 0.12–0.67), without apparent heterogeneity by age, sex, and AF type, and for risk score subgroups.

Conclusions

In this propensity-matched elderly sample, ablation therapy was associated with lower risk of composite outcome consisting of all-cause death, non-fatal stroke, and peripheral embolism, and therefore might be an alternative to conservative therapy.

Cabins, castles, and constant hearts: rhythm control therapy in patients with atrial fibrillation

Recent innovations have the potential to improve rhythm control therapy in patients with atrial fibrillation (AF). Controlled trials provide new evidence on the effectiveness and safety of rhythm control therapy, particularly in patients with AF and heart failure. This review summarizes evidence supporting the use of rhythm control therapy in patients with AF for different outcomes, discusses implications for indications, and highlights remaining clinical gaps in evidence. Rhythm control therapy improves symptoms and quality of life in patients with symptomatic AF and can be safely delivered in elderly patients with comorbidities (mean age 70 years, 3-7% complications at 1 year). Atrial fibrillation ablation maintains sinus rhythm more effectively than antiarrhythmic drug therapy, but recurrent AF remains common, highlighting the need for better patient selection (precision medicine). Antiarrhythmic drugs remain effective after AF ablation, underpinning the synergistic mechanisms of action of AF ablation and antiarrhythmic drugs. Atrial fibrillation ablation appears to improve left ventricular function in a subset of patients with AF and heart failure. Data on the prognostic effect of rhythm control therapy are heterogeneous without a clear signal for either benefit or harm. Rhythm control therapy has acceptable safety and improves quality of life in patients with symptomatic AF, including in elderly populations with stroke risk factors. There is a clinical need to better stratify patients for rhythm control therapy. Further studies are needed to determine whether rhythm control therapy, and particularly AF ablation, improves left ventricular function and reduces AF-related complications.

A Long-Term Cost-Effectiveness Analysis Comparing Radiofrequency Catheter Ablation with Antiarrhythmic Drugs in Treatment of Chinese Patients with Atrial Fibrillation

INTRODUCTION

Radiofrequency catheter ablation (RFCA) is widely used to treat atrial fibrillation (AF) in China.

OBJECTIVE

We aimed to determine the long-term cost effectiveness of RFCA versus antiarrhythmic drugs (AADs) in treating AF from the perspective of third-party payers.

METHODS

The model was structured as a 12-month decision tree leading to a Markov model that simulated the follow-up treatment outcomes and costs with time horizons of 8, 15, and 20 years. Comparators were standard-of-care AADs. Clinical parameters captured normal sinus rhythm, AF, stroke, post-stroke, intracranial hemorrhage (ICH), gastrointestinal bleeding, post-ICH, and death. The risk of operative death, procedural complications, and adverse drug toxicity were also considered. The model output was quality-adjusted life-years (QALYs) and incremental cost per QALY gained.

RESULTS

RFCA incurred more costs than the AADs but resulted in more QALYs gained than did AADs. The incremental cost per QALY gained with RFCA versus AADs was ¥66,764, ¥36,280, and ¥29,359 at 8, 15, and 20 years, respectively. The sensitivity analyses showed that the results were most sensitive to the changes in RFCA cost and CHADS₂ score (clinical prediction rule for assessing the risk of stroke in patients with non-rheumatic AF).

CONCLUSION

Compared with AADs, RFCA significantly improves clinical outcomes and QALYs among patients with paroxysmal or persistent AF. From the Chinese payer's perspective, RFCA is a cost-effective therapy over long-term horizons.

Catheter Ablation Versus Best Medical Therapy in Patients With Persistent Atrial Fibrillation and Congestive Heart Failure

Background:

Optimal treatment of patients with persistent atrial fibrillation (AF) and heart failure (HF) with reduced left ventricular ejection fraction (LVEF) and an indication for internal defibrillator therapy is controversial.

Methods:

Patients with persistent/longstanding persistent AF and LVEF ≤35% were randomly allocated to catheter ablation of AF or best medical therapy (BMT). The primary study end point was the absolute increase in LVEF from baseline at 1 year. Secondary end points included 6-minute walk test, quality-of-life, and NT-proBNP (N-terminal pro-brain natriuretic peptide). Pulmonary vein isolation was the primary ablation approach; BMT comprised rate or rhythm control. All patients were discharged after index hospitalization with a cardioverter-defibrillator or cardiac resynchronization therapy defibrillator implanted. The study was terminated early for futility.

Results:

Of 140 patients (65±8 years, 126 [90%] men) available for the end point analysis, 68 and 72 patients were assigned to ablation and BMT, respectively. At 1 year, LVEF had increased in ablation patients by 8.8% (95% CI, 5.8%–11.9%) and in BMT patients by 7.3% (4.3%–10.3%; P =0.36). Sinus rhythm was recorded on 12-lead electrocardiograms at 1 year in 61/83 ablation patients (73.5%) and 42/84 BMT patients (50%). Device-recorded AF burden at 1 year was 0% or maximally 5% of the time in 28/39 ablation patients (72%) and 16/36 BMT patients (44%). There was no difference in secondary end point outcome between ablation patients and BMT patients.

Conclusions:

The AMICA trial (Atrial Fibrillation Management in Congestive Heart Failure With Ablation) did not reveal any benefit of catheter ablation in patients with AF and advanced HF. This was mainly because of the fact that at 1 year, LVEF increased in ablation patients to a similar extent as in BMT patients. The effect of catheter ablation of AF in patients with HF may be affected by the extent of HF at baseline, with a rather limited ablation benefit in patients with seriously advanced HF.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT00652522.

[Catheter ablation of atrial fibrillation : Status quo]

Catheter ablation of atrial fibrillation (AF) is a standard part of treatment with respect to rhythm control. In this article, the authors provide a review of the state-of-the-art knowledge of AF catheter ablation including current indications, possible energy forms, procedural methods and endpoints as well as follow-up and further anticoagulation.

Long-term impact of catheter ablation on arrhythmia burden in low-risk patients with paroxysmal atrial fibrillation: The CLOSE to CURE study

BACKGROUND

Few studies evaluated the impact of catheter ablation (CA) on atrial tachyarrhythmia (ATA) burden in paroxysmal atrial fibrillation (AF).

OBJECTIVE

In the prospective, patient-controlled CLOSE to CURE study, we determined the longer-term impact of optimized CA on ATA burden by using an insertable cardiac monitor (ICM).

METHODS

A total of 105 patients with paroxysmal AF were implanted with an ICM 65 (interquartile range [IQR] 61-78) days before CA. CA consisted of contact force-guided pulmonary vein isolation targeting an intertag distance of ≤6 mm and a region-specific ablation index. The primary end point was reduction in ICM-detected ATA burden; secondary end points were single-procedure freedom from ATA, quality of life, and adverse events.

RESULTS

The mean age was 62 ± 8 years; the median CHA₂DS₂-VASc score was 1 (IQR 1-2); and the median left atrial diameter was 43 (IQR 39-43) mm. After pulmonary vein isolation (1.13 ± 0.39 procedures per patient), median ATA burden decreased from 2.68% (IQR 0.09%-15.02%) at baseline to 0% (IQR 0%-0%) during the first year and to 0% (IQR 0%-0%) during the second year (reduction in ATA burden 100% [IQR 100%-100%]; P < .001). Single-procedure freedom from any ATA was 87% at 1 year and 78% at 2 years. Quality of life improved significantly across all scores. Adverse events occurred in 5 patients (4.8%).

CONCLUSION

CA has become an effective procedure in paroxysmal AF, with a major impact on ICM-detected ATA burden. Whereas conventional survival analysis suggests a progressive decline in efficacy, we observed that burden reduction is maintained at longer follow-up. These data imply that ATA burden is a more optimal end point for assessing ablation efficacy.

Cryoballoon or Radiofrequency Ablation for Atrial Fibrillation Assessed by Continuous Monitoring: A Randomized Clinical Trial

BACKGROUND

Advanced generation ablation technologies have been developed to achieve more effective pulmonary vein isolation (PVI) and minimize arrhythmia recurrence after atrial fibrillation (AF) ablation.

METHODS

We randomly assigned 346 patients with drug-refractory paroxysmal AF to contact force-guided radiofrequency ablation (CF-RF; n=115), 4-minute cryoballoon ablation (Cryo-4; n=115), or 2-minute cryoballoon ablation (Cryo-2; n=116). Follow-up was 12 months. The primary outcome was time to first documented recurrence of symptomatic or asymptomatic atrial tachyarrhythmia (AF, atrial flutter, or atrial tachycardia) between days 91 and 365 after ablation or a repeat ablation procedure at any time. Secondary end points included freedom from symptomatic arrhythmia and AF burden. All patients received an implantable loop recorder.

RESULTS

One-year freedom from atrial tachyarrhythmia defined by continuous rhythm monitoring was 53.9%, 52.2%, and 51.7% with CF-RF, Cryo-4, and Cryo-2, respectively (P=0.87). One-year freedom from symptomatic atrial tachyarrhythmia defined by continuous rhythm monitoring was 79.1%, 78.2%, and 73.3% with CF-RF, Cryo-4, and Cryo-2, respectively (P=0.26). Compared with the monitoring period before ablation, AF burden was reduced by a median of 99.3% (interquartile range, 67.8%-100.0%) with CF-RF, 99.9% (interquartile range, 65.3%-100.0%) with Cryo-4, and 98.4% (interquartile range, 56.2%-100.0%) with Cryo-2 (P=0.36). Serious adverse events occurred in 3 patients (2.6%) in the CF-RF group, 6 patients (5.3%) in the Cryo-4 group, and 7 patients (6.0%) in the Cryo-2 group, with no significant difference between groups (P=0.24). The CF-RF group had a significantly longer procedure duration but significantly shorter fluoroscopy exposure (P<0.001 vs cryoballoon groups).

CONCLUSIONS

In this multicenter, randomized, single-blinded trial, CF-RF and 2 different regimens of cryoballoon ablation resulted in no difference in 1-year efficacy, which was 53% by time to first recurrence but >98% burden reduction as assessed by continuous cardiac rhythm monitoring.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01913522.

Budget Impact of Cryoablation Versus Radiofrequency Ablation of Atrial Fibrillation in the Brazilian Public Healthcare System

BACKGROUND

Cryoablation is a new technology for ablation of atrial fibrillation (AF), effective and safe when compared with standard radiofrequency (RF) ablation. Nevertheless, the economic impact of its incorporation is unknown, especially considering the public health system of a developing country. This study analyzed the budget impact of cryoablation incorporation for treatment of paroxysmal AF in the Brazilian public health system.

METHODS

The budget impact was calculated as the cost difference between the current scenario (RF ablation guided by electroanatomic mapping) and the new scenario (cryoablation). The cost of each intervention was obtained by multiplying the price of a single procedure by the number of candidates for it. Other technologies (RF ablation guided by intracardiac echocardiography or with a nonirrigated catheter) were considered in a sensitivity analysis.

RESULTS

The budget impact showed savings of $43 097 096.84 with cryoablation. In the sensitivity analysis, cryoablation resulted in cost savings compared with RF ablation guided by intracardiac echocardiography, whereas in comparison to RF ablation with the nonirrigated catheter, cryoablation was more expensive. A market share assessment, performed using an incorporation rate of 3% per year, indicated savings of approximately $800 000 per 5 years.

CONCLUSIONS

Cryoablation of AF resulted in cost savings compared with the current scenario (RF ablation guided by electroanatomic mapping). When alternative technologies were considered, cryoablation was more expensive than RF ablation with a nonirrigated catheter, but it also resulted in savings compared with RF ablation guided by intracardiac echocardiography. Overall, cryoablation of AF may reduce expenditures in the Brazilian public health system.

Periprocedural Anticoagulation Management For Nonoperating Room Anesthesia Procedures: A Clinical Guide

Non-operating room anesthesia presents unique challenges for anesthesiologists. Limited preprocedural optimization and unfamiliarity with the location and procedure itself add to the difficulties in delivering safe care for these patients. Management of chronic oral anticoagulation can prove especially problematic since risks of bleeding for non-operating room procedures vary widely and differ from traditional surgeries. In addition, many physicians may not be familiar with the growing number of newly approved oral anticoagulants and their periprocedural management. This review will examine common non-operating procedures, their risks of bleeding, as well as pharmacokinetics of oral anticoagulants available on the market and periprocedural management options.

Catheter Ablation Versus Medical Therapy for Atrial Fibrillation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Despite the publication of several randomized clinical trials comparing catheter ablation (CA) with medical therapy (MT) in patients with atrial fibrillation (AF), the superiority of one strategy over another is still questioned by many. In this meta-analysis of randomized controlled trials, we compared the efficacy and safety of CA with MT for AF.

METHODS

We systematically searched MEDLINE, EMBASE, and other online sources for randomized controlled trials of AF patients that compared CA with MT. The primary outcome was all-cause mortality. Secondary outcomes included cardiovascular hospitalizations and recurrence of atrial arrhythmia. Subgroup analyses stratified by the presence of heart failure with reduced ejection fraction, type of AF, age, and sex were performed. Risk ratios (RRs) with 95% CIs were calculated using a random effects model, and Mantel-Haenszel method was used to pool RR.

RESULTS

Eighteen randomized controlled trials comprising 4464 patients (CA, n=2286; MT, n=2178) were included. CA resulted in a significant reduction in all-cause mortality (RR, 0.69; 95% CI, 0.54-0.88; P=0.003) that was driven by patients with AF and heart failure with reduced ejection fraction (RR, 0.52; 95% CI, 0.35-0.76; P=0.0009). CA resulted in significantly fewer cardiovascular hospitalizations (hazard ratio, 0.56; 95% CI, 0.39-0.81; P=0.002) and fewer recurrences of atrial arrhythmias (RR, 0.42; 95% CI, 0.33-0.53; P<0.00001). Subgroup analyses suggested that younger patients (age, <65 years) and men derived more benefit from CA compared with MT.

CONCLUSIONS

CA is associated with all-cause mortality benefit, that is driven by patients with AF and heart failure with reduced ejection fraction. CA reduces cardiovascular hospitalizations and recurrences of atrial arrhythmia for patients with AF. Younger patients and men appear to derive more benefit from CA.

Ablation, rate or rhythm control strategies for patients with atrial fibrillation: how do they affect mid-term clinical outcomes?

BACKGROUND

Transcatheter ablation (Abl) of atrial fibrillation (AF) is regarded as the best therapeutic solution for severely symptomatic patients, in whom at least one antiarrhythmic drug has been tested.

METHODS

In the present retrospective study, 175 cases of paroxysmal, persistent or long-lasting persistent AF have been gathered, and grouped depending on therapeutic approach: Abl, isolated or followed by chronic use of antiarrhythmics (N.=74), drug treatment for rate control strategy (N.=60), and drug treatment for rhythm control strategy (N.=41). The effects respectively exerted by the three treatment modalities on the primary endpoint, namely a composite of death, disabling stroke, severe bleeding and cardiac arrest, have been compared through a median follow-up of 20 months (interquartile range: 18-24 months) using the Cox proportional-hazards regression analysis. Further exposure variables were hypertension, the A-P diameter of the left atrium, the left ventricular ejection fraction and AF relapses.

RESULTS

The rhythm control strategy and AF recurrences during the follow-up were associated with increased risk of the primary composite endpoint as documented by the Cox model (for the former, hazard ratio [HR]: 3.3159; 95% CI: 1.5415 to 7.1329; P=0.0023; for the latter, HR: 1.0448; 95% CI: 1.0020 to 1.0895; P=0.0410). Even hypertension was associated with an increased risk (HR: 1.1040; 95% CI: 1.0112 to 1.9662; P=0.0477). On the contrary, a rate control strategy predicted a decreased risk of experiencing the primary endpoint (HR: 0.0711; 95% CI: 0.0135 to 0.3738; P=0.0019) while Abl did not exert a statistically significant effect on the same outcome.

CONCLUSIONS

AF ablation is able to decrease the arrhythmic episodes but does not offer a statistically significant protection against the composite of death, disabling stroke, severe bleeding and cardiac arrest in the mid-term follow-up.

Ablation versus Anti-Arrhythmic Therapy for Reducing All Hospital Episodes from Recurrent Atrial Fibrillation (AVATAR-AF): Design and rationale

Atrial Fibrillation (AF) ablation using the cryoballoon is effective at reducing symptomatic AF episodes. The prevalence of AF is increasing with the aging population and access to such treatment would be enhanced by reducing the resource requirements. Relinquishing electrical mapping of the pulmonary veins (PV) removes the need for PV catheters, electrical recording equipment and staff trained in using this equipment. Moreover, the majority of complications are peri-procedural so overnight hospitalization maybe unnecessary. We tested this streamlined approach to AF ablation against medical therapy using the endpoint of time to all hospital episodes. METHODS: The AVATAR-AF study is a prospective, multicenter, randomized controlled trial testing the primary hypothesis that AF ablation done without PV mapping or overnight hospitalization is more effective than anti-arrhythmic drugs at reducing all hospital episodes related to recurrent atrial arrhythmias. We included a third arm to test a secondary hypothesis that confirming PV entrance block as per consensus guidelines can improve outcomes. Three hundred twenty-one patients with documented paroxysmal AF will be randomized in a 1:1:1 manner to one of three investigation arms: (1) AVATAR protocol cryoballoon ablation without assessment of acute PV isolation or overnight hospitalization; (2) medical therapy with anti-arrhythmic drugs; or (3) conventional cryoballoon ablation with assessment of acute PV isolation. The primary endpoint is defined as the time to all hospital episodes (including outpatient consultation) related to treatment for atrial arrhythmia. CONCLUSION: The AVATAR-AF study will determine whether the resource utilization for AF ablation can be reduced whilst maintaining superiority over medical therapy.

2018 Focused Update of the Canadian Cardiovascular Society Guidelines for the Management of Atrial Fibrillation

The Canadian Cardiovascular Society (CCS) Atrial Fibrillation Guidelines Committee provides periodic reviews of new data to produce focused updates that address clinically important advances in atrial fibrillation (AF) management. This 2018 Focused Update addresses: (1) anticoagulation in the context of cardioversion of AF; (2) the management of antithrombotic therapy for patients with AF in the context of coronary artery disease; (3) investigation and management of subclinical AF; (4) the use of antidotes for the reversal of non-vitamin K antagonist oral anticoagulants; (5) acute pharmacological cardioversion of AF; (6) catheter ablation for AF, including patients with concomitant AF and heart failure; and (7) an integrated approach to the patient with AF and modifiable cardiovascular risk factors. The recommendations were developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) standards. Individual studies and literature were reviewed for quality and bias; the literature review process and evidence tables are included as Supplementary Material and are available on the CCS Web site. Details of the updated recommendations are presented, along with their background and rationale. This document is linked to an updated summary of all CCS AF guidelines recommendations, from 2010 to the present 2018 Focused Update, which is provided in the Supplementary Material.

Shorter Leukocyte Telomere Length Is Associated With Atrial Remodeling and Predicts Recurrence in Younger Patients With Paroxysmal Atrial Fibrillation After Radiofrequency Ablation

BACKGROUND

Telomere length is a biologic aging marker. This study investigated leukocyte telomere length (LTL) as a new biomarker to predict recurrence after paroxysmal atrial fibrillation (PAF) ablation.Methods and Results:A total of 131 participants (26 healthy individuals and 105 symptomatic PAF patients) were enrolled. PAF patients (54.1±10.8 years) who received catheter ablation therapy were divided into 2 groups: recurrent AF (n=25) and no recurrent AF after catheter ablation (n=80). Peripheral blood mononuclear cells were collected from all subjects to measure LTL. Under 50 years old, LTL in healthy individuals (n=17) was longer than in PAF patients (n=31; 7.34±0.58 kbp vs. 6.44±0.91 kbp, P=0.01). In PAF patients, LTL was positively correlated with left atrial bipolar voltage (R=0.497, P<0.001), and negatively correlated with biatrial scar area (R=-0.570, P<0.001) and left atrial diameter (R=-0.214, P=0.028). LTL was shorter in the patients with recurrent AF than in those without recurrent AF after catheter ablation (5.68±0.82 kbp vs. 6.66±0.71 kbp; P<0.001). On receiver operating characteristic curve analysis, LTL cut-off <6.14 kbp had a specificity of 0.68 and sensitivity of 0.79 to predict recurrent AF after catheter ablation.

CONCLUSIONS

Young PAF patients (≤50 years) had shorter LTL. Shorter LTL was associated with a degenerative atrial substrate and recurrence after catheter ablation in younger PAF patients.

Association between reactive hyperemia peripheral arterial tonometry index and atrial fibrillation recurrence after catheter ablation

Background

Vascular endothelial function has recently been recognized as an independent predictor of cardiovascular events. However, studies investigating its association with atrial fibrillation (AF) are lacking. This study aimed to examine association with AF recurrence and vascular endothelial function as assessed using natural logarithmic transformation of reactive hyperemia peripheral arterial tonometry index (LnRHI).

Methods

Ninety-nine consecutive AF patients who underwent catheter ablation (CA) at Shinshu University Hospital between September 2015 and April 2017 were enrolled. LnRHI was measured 48 to 72 h before CA using the EndoPAT system. The primary outcome was AF recurrence beyond 3 months post-ablation.

Results

A total of 30 (30.3%) patients experienced AF recurrence after CA over a median follow-up period of 210 days (range: 93–764 days). Female sex and low LnRHI were significantly associated with AF recurrence. In multivariate analysis, LnRHI was an independent predictor of AF recurrence (hazard ratio: 0.087, 95% confidence interval 0.015–0.51, p = 0.007). In comparison in Kaplan-Meier analysis of high LnRHI (LnRHI ≥0.52, n = 52) and low LnRHI (LnRHI ≪0.52, n = 47) groups, AF recurrence rate was significantly higher in the low LnRHI group (log-rank test, p = 0.043). A negative correlation was observed between LnRHI and AF duration, whereby LnRHI was significantly decreased when the duration of AF events exceeded 1 year.

Conclusion

Decreased LnRHI was associated with AF recurrence after CA and prolonged AF duration.

Tackling Patient-Reported Outcomes in Atrial Fibrillation and Heart Failure: Identifying Disease-Specific Symptoms?

Atrial fibrillation (AF) and heart failure (HF) both significantly affect morbidity and mortality and also account for high symptom burden and impaired health-related quality of life (hrQoL). Several well-designed and broadly implemented patient-reported outcome instruments are available for both AF and HF and can easily measure hrQoL in each disease process. A better understanding of the diverse phenotypes of AF and HF, as well as the heterogeneous treatment effects of disease-specific interventions, is necessary to further disentangle the complex relationship between symptoms of AF and HF.

Plasma big endothelin-1 predicts new-onset atrial fibrillation after surgical septal myectomy in patients with hypertrophic cardiomyopathy

Background

Postoperative atrial fibrillation (POAF) is a common complication in patients with obstructive hypertrophic cardiomyopathy (HOCM) who undergo surgical myectomy. POAF is associated with poor outcome. The role of plasma big endothelin-1 level in predicting atrial fibrillation after surgical septal myectomy in HOCM patients has not well been studied.

Methods

A total of 118 patients with HOCM who underwent surgical septal myectomy were recruited in this study. Plasma big endothelin-1 level was measured. The heart rhythm was continuously monitored during hospital stay. Preoperative, intraoperative, and postoperative variables were collected.

Results

POAF developed among 26 of the 118 patients (22%) in this study. Compared with those without POAF, patients with POAF were significantly older (53.5 ± 10.6 vs. 47.3 ± 13.6 years, P = 0.033), more likely to undergo mitral valve surgery (38.5% vs. 18.5%, P = 0.032), and had higher plasma big endothelin-1 levels (0.41 ± 0.19 vs. 0.27 ± 0.14 pmol/l, P = 0.001), longer hospital stay (9.1 ± 3.7 vs. 7.5 ± 2.8 days, P = 0.022), larger preoperative left atria (48.0 ± 5.2 vs. 44.1 ± 5.9 mm; P = 0.003). In the receiver operating characteristic curve analysis, the area under the curve for big endothelin-1 was 0.734 (95% CI, 0.634 to 0.834, P<0.001). In multivariate logistic regression analysis, preoperative big endothelin-1 level (OR 100.7, 95%CI: 5.0–2020.0, P = 0.003) and left atrial diameter (OR 1.106, 95%CI: 1.015–1.205, P = 0.022) were independent predictors of POAF.

Conclusion

Elevated preoperative plasma big endothelin-1 level is an independent predictor of POAF in HOCM patients undergoing surgical septal myectomy.

Evaluation of the effect of prior antiarrhythmic drug use on the success of atrial fibrillation catheter ablation

WHAT IS KNOWN AND OBJECTIVE

Current guidelines recommend catheter ablation (CA) for atrial fibrillation (AF) refractory to at least one antiarrhythmic drug (AAD), but do not specify an adequate number of AADs to be trialed prior to considering ablation. The objective of this study was to evaluate the effect of CA success based on the number of AADs failed in patients with paroxysmal or persistent AF.

METHODS

This retrospective cohort study evaluated patients with paroxysmal or persistent AF who underwent an initial CA at a community hospital. Patients with unknown AAD histories, those who did not achieve acute procedural success, or who were lost to follow-up or death unrelated to thromboembolic stroke within 6 months post-ablation were excluded. Catheter ablation success was defined as freedom from AF. The primary outcome was the incidence of AF or atrial flutter captured on an electrocardiogram or other recording device at 3, 6, 9 and 12 months after the procedure.

RESULTS AND DISCUSSION

Overall, 99 out of 103 patients completed 1 year of follow-up. Of those patients, 34 of 99 (34.3%) experienced AF recurrence within 1-year post-ablation. There was no significant difference among the categories of number of failed AADs and the recurrence of AF within 12 months post-ablation for zero AADs, 1 AADs and ≥2 AADs (41.7%, 31.3% and 40%, respectively; P = 0.658).

WHAT IS NEW AND CONCLUSION

The results of this study do not support preferentially performing CA on patients who have failed a certain number of AADs. Results are limited by the nature of the study design and a small sample size. Conclusive results would best be addressed by a prospective randomized trial.

Clinical and Echocardiographic Risk Factors Predict Late Recurrence after Radiofrequency Catheter Ablation of Atrial Fibrillation

The benefits of radiofrequency catheter ablation (RFCA) for patients with atrial fibrillation (AF) significantly decrease with late recurrence (LR). We aimed to develop a scoring system to identify patients at high and low risk for LR following RFCA, based on a comprehensive evaluation of multiple risk factors for AF recurrence, including echocardiographic parameters. We studied 2,352 patients with AF undergoing first-time RFCA in a single institution. The LR-free survival rate up to 5 years was measured using a Kaplan-Meier analysis. The influence of clinical and echocardiographic parameters on LR was calculated with a Cox-regression analysis. Duration of AF ≥4 years (hazard ratio [HR] = 1.75; p < 0.001), non-paroxysmal AF (HR = 3.18; p < 0.001), and diabetes (HR = 1.34; p = 0.015) were associated with increased risk of LR. Left atrial (LA) diameter ≥45 mm (HR = 2.42; p < 0.001), E/e' ≥ 10 (HR = 1.44; p < 0.001), dense SEC (HR = 3.30; p < 0.001), and decreased LA appendage flow velocity (≤40 cm/sec) (HR = 2.35; p < 0.001) were echocardiographic parameters associated with increased risk of LR following RFCA. The LR score based on the aforementioned risk factors could be used to predict LR (area under curve = 0.717) and to stratify the risk of LR (HR = 1.45 per 1 point increase in the score; p < 0.001). In conclusion, LR after RFCA is affected by multiple clinical and echocardiographic parameters. This study suggests that combining these multiple risk factors enables the identification of patients with AF at high or low risk for having arrhythmia recurrence.

Rate Control Yields Better Clinical Outcomes Over a Median Follow-Up of 20 Months Compared to Rhythm Control Strategy in Patients With a History of Atrial Fibrillation: A Retrospective Cohort Study

Background

Clinical management of patients with a history of atrial fibrillation (AF) focuses on the goal of preventing AF recurrences, or, if this is impossible due to the fact that the arrhythmia has by now become permanent, it is aimed at the control of the ventricular response. In patients with AF, an important topic is the comparative evaluation in the mid/long-term of clinical outcomes arising from the various therapeutic regimens, including pharmacological approaches as well as radiofrequency catheter ablation (abl).

Methods

In the present cohort retrospective study, 175 cases of paroxysmal, persistent or long-lasting persistent AF have been grouped depending on therapeutic approach: abl-isolated or followed by chronic use of antiarrhythmics (74 cases), drug treatment for rate control strategy (60 cases), drug treatment for rhythm control strategy (41 cases). The effects respectively exerted by the three treatment modalities on the primary endpoint, namely a composite of death, disabling stroke, severe bleeding and cardiac arrest , have been compared through a median follow-up of 20 months (interquartile range = 18 - 24 months) using the Cox proportional-hazards regression analysis.

Results

As documented by the Cox model, an increased risk of the primary composite endpoint was associated with the rhythm control strategy, as well as with the AF recurrences during the follow-up (for the former, hazard ratio (HR): 3.3159, 95% CI: 1.5415 to 7.1329, P = 0.0023; for the latter, HR: 1.0448, 95% CI: 1.0020 to 1.0895, P = 0.0410). Even hypertension was associated with an increased risk (HR: 1.1040; 95% CI: 1.0112 to 1.9662; P = 0.0477). On the contrary, a rate control strategy predicted a decreased risk of experiencing the primary endpoint (HR: 0.0711; 95% CI: 0.0135 to 0.3738; P = 0.0019) while abl did not exert a statistically significant effect on the same outcome.

Conclusions

AF abl decreases the arrhythmic episodes but does not provide a statistically significant protection against the composite of death, disabling stroke, major bleeding and cardiac arrest after a 20-month follow-up. Moreover, in patients with a history of AF, rate control compared to rhythm control strategy provides better clinical outcomes over a mid-term follow-up.

Effect of Catheter Ablation vs Antiarrhythmic Drug Therapy on Mortality, Stroke, Bleeding, and Cardiac Arrest Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial

IMPORTANCE

Catheter ablation is effective in restoring sinus rhythm in atrial fibrillation (AF), but its effects on long-term mortality and stroke risk are uncertain.

OBJECTIVE

To determine whether catheter ablation is more effective than conventional medical therapy for improving outcomes in AF.

DESIGN, SETTING, AND PARTICIPANTS

The Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation trial is an investigator-initiated, open-label, multicenter, randomized trial involving 126 centers in 10 countries. A total of 2204 symptomatic patients with AF aged 65 years and older or younger than 65 years with 1 or more risk factors for stroke were enrolled from November 2009 to April 2016, with follow-up through December 31, 2017.

INTERVENTIONS

The catheter ablation group (n = 1108) underwent pulmonary vein isolation, with additional ablative procedures at the discretion of site investigators. The drug therapy group (n = 1096) received standard rhythm and/or rate control drugs guided by contemporaneous guidelines.

MAIN OUTCOMES AND MEASURES

The primary end point was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Among 13 prespecified secondary end points, 3 are included in this report: all-cause mortality; total mortality or cardiovascular hospitalization; and AF recurrence.

RESULTS

Of the 2204 patients randomized (median age, 68 years; 37.2% female; 42.9% had paroxysmal AF and 57.1% had persistent AF), 89.3% completed the trial. Of the patients assigned to catheter ablation, 1006 (90.8%) underwent the procedure. Of the patients assigned to drug therapy, 301 (27.5%) ultimately received catheter ablation. In the intention-to-treat analysis, over a median follow-up of 48.5 months, the primary end point occurred in 8.0% (n = 89) of patients in the ablation group vs 9.2% (n = 101) of patients in the drug therapy group (hazard ratio [HR], 0.86 [95% CI, 0.65-1.15]; P = .30). Among the secondary end points, outcomes in the ablation group vs the drug therapy group, respectively, were 5.2% vs 6.1% for all-cause mortality (HR, 0.85 [95% CI, 0.60-1.21]; P = .38), 51.7% vs 58.1% for death or cardiovascular hospitalization (HR, 0.83 [95% CI, 0.74-0.93]; P = .001), and 49.9% vs 69.5% for AF recurrence (HR, 0.52 [95% CI, 0.45-0.60]; P < .001).

CONCLUSIONS AND RELEVANCE

Among patients with AF, the strategy of catheter ablation, compared with medical therapy, did not significantly reduce the primary composite end point of death, disabling stroke, serious bleeding, or cardiac arrest. However, the estimated treatment effect of catheter ablation was affected by lower-than-expected event rates and treatment crossovers, which should be considered in interpreting the results of the trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00911508.

Analysis of late reconnections after pulmonary vein isolation: Impact of interlesion contiguity and ablation index

BACKGROUND

Interlesion distance and ablation index (AI) have been proposed as parameters of radiofrequency (RF) lesion durability. This study analyzes the relationship between RF parameters of automatically acquired lesion tags and late reconnections in repeat pulmonary vein isolation (PVI) procedures.

METHODS

One hundred fifty-seven patients underwent contact force (CF)-guided PVI with automatic acquisition of RF lesions. During follow-up, 21 patients underwent a repeat PVI procedure. The relationship between RF parameters (power, CF, impedance drop, and AI) of the initial PVI procedure and reconnections observed at repeat PVI was analyzed. Visual gap was defined as the existence of a discontinuity between two RF lesions automatically acquired in the initial PVI procedure. Regional values of AI associated with lesion durability were identified.

RESULTS

Twenty-one patients were included. Three hundred thirty-six segments and 2507 RF lesions were analyzed. The median interval between the initial and repeat PVI procedures was 17 (11-24) months. All patients showed ≥1 reconnected segment. Sixty-three segments (18.7%) were reconnected. Reconnected segments showed visual gaps more frequently than non-reconnected segments (66.6% vs 17.6%; P < .001; negative predictive value 91.4%). The mean distance of visual gaps was 8 ± 2.8 mm. No differences were observed in power (31.4 ± 4.7 W vs 31 ± 4.1 W; P = .573), CF (14.4 ± 5.3 g vs 15.4 ± 5.4 g; P = .315), and impedance drop (6.9 ± 5.2 ohms vs 6.5 ± 3.8 ohms; P = .576) between reconnected and non-reconnected segments. Among segments without visual gap, the minimum AI value was significantly higher in the non-reconnected segments (325 ± 96.1 vs 204.7 ± 78.5; P < .001). No reconnections were observed in segments without visual gap and minimum AI ≥ 330/220 in anterior/posterior wall, respectively.

CONCLUSIONS

Contiguity between automatically acquired RF lesions and minimum AI value are the main determinants of long-term PVI durability.

Early choice for catheter ablation reduced readmission in management of atrial fibrillation: Impact of diagnosis-to-ablation time

BACKGROUND

The impact of delays in the treatment with radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) has not been well evaluated. The aim of this study was to investigate the impact of diagnosis-to-ablation time (DAT) on the long-term clinical outcomes after AF-RFCA.

METHODS

We enrolled 1206 consecutive patients undergoing first-time RFCA for AF. The study population was divided into 2 groups based on DAT: short (<3 years) (N = 675) and long (>3 years) (N = 531) DAT groups.

RESULTS

Mean follow-up duration was 5.0 ± 2.5 years. The 5-year event-free rates from recurrent atrial tachyarrhythmias after the first and second RFCAs were significantly higher in short DAT group than in long DAT group (60.2% versus 48.3%, log-rank P < 0.001; 83.2% versus 75.2%, log-rank P = 0.02, respectively), leading to reduced cardiovascular hospitalization in short DAT group. After adjusting baseline differences, short DAT was independently associated with lower arrhythmia recurrence rates after the first and second RFCAs (hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.60-0.86 and HR 0.72, 95%CI 0.55-0.95, respectively). There were no significant differences between the 2 groups in the event-free rates from all-cause and cardiovascular deaths, heart failure hospitalization, and ischemic stroke. However, among patients with a history of heart failure or reduced left ventricular function, the event-free rate from heart failure readmission was significantly higher in short DAT group (85.0% versus 61.0%, P = 0.004).

CONCLUSIONS

In the management of AF, early RFCA was associated with significantly lower arrhythmia recurrence compared with delayed RFCA, leading to reduced cardiovascular hospitalization, especially in heart failure patients.

Effect of Catheter Ablation vs Antiarrhythmic Medication on Quality of Life in Patients With Atrial Fibrillation: The CAPTAF Randomized Clinical Trial

IMPORTANCE

Quality of life is not a standard primary outcome in ablation trials, even though symptoms drive the indication.

OBJECTIVE

To assess quality of life with catheter ablation vs antiarrhythmic medication at 12 months in patients with atrial fibrillation.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial at 4 university hospitals in Sweden and 1 in Finland of 155 patients aged 30-70 years with more than 6 months of atrial fibrillation and treatment failure with 1 antiarrhythmic drug or β-blocker, with 4-year follow-up. Study dates were July 2008-September 2017. Major exclusions were ejection fraction <35%, left atrial diameter >60 mm, ventricular pacing dependency, and previous ablation.

INTERVENTIONS

Pulmonary vein isolation ablation (n = 79) or previously untested antiarrhythmic drugs (n = 76).

MAIN OUTCOMES AND MEASURES

Primary outcome was the General Health subscale score (Medical Outcomes Study 36-Item Short-Form Health Survey) at baseline and 12 months, assessed unblinded (range, 0 [worst] to 100 [best]). There were 26 secondary outcomes, including atrial fibrillation burden (% of time) from baseline to 12 months, measured by implantable cardiac monitors. The first 3 months were excluded from rhythm analysis.

RESULTS

Among 155 randomized patients (mean age, 56.1 years; 22.6% women), 97% completed the trial. Of 79 patients randomized to receive ablation, 75 underwent ablation, including 2 who crossed over to medication and 14 who underwent repeated ablation procedures. Of 76 patients randomized to receive antiarrhythmic medication, 74 received it, including 8 who crossed over to ablation and 43 for whom the first drug used failed. General Health score increased from 61.8 to 73.9 points in the ablation group vs 62.7 to 65.4 points in the medication group (between-group difference, 8.9 points; 95% CI, 3.1-14.7; P = .003). Of 26 secondary end points, 5 were analyzed; 2 were null and 2 were statistically significant, including decrease in atrial fibrillation burden (from 24.9% to 5.5% in the ablation group vs 23.3% to 11.5% in the medication group; difference -6.8% [95% CI, -12.9% to -0.7%]; P = .03). Of the Health Survey subscales, 5 of 7 improved significantly. Most common adverse events were urosepsis (5.1%) in the ablation group and atrial tachycardia (3.9%) in the medication group.

CONCLUSIONS AND RELEVANCE

Among patients with symptomatic atrial fibrillation despite use of antiarrhythmic medication, the improvement in quality of life at 12 months was greater for those treated with catheter ablation compared with antiarrhythmic medication. Although the study was limited by absence of blinding, catheter ablation may offer an advantage for quality of life.

TRIAL REGISTRATION

clinicaltrialsregister.eu Identifier: 2008-001384-11.

Changes in heart rate variability in patients with atrial fibrillation after pulmonary vein isolation and ganglionated plexus ablation

Pulmonary vein isolation (PVI) is the cornerstone in the treatment of patients with paroxysmal atrial fibrillation (PAF). Some research has suggested studies have shown that modification of ganglionated plexuses (GP), performed with PVI, could lead to even better outcomes. The aim of this study was to determine the effect of PVI on the autonomic system. Heart rate variability (HRV) was used as a marker of autonomic system activity. Twenty-six PAF patients underwent PVI (PVI group) and twenty patients underwent PVI plus a GP ablation (GP group). In each group, 5 min long ECG signals obtained before and after the electrophysiology EP study were analyzed. Time and frequency domain parameters were evaluated. Vagal responses during ablation were observed in 15 (58 %) patients in the PVI group and in 12 (60 %) patients in the GP group. The change in normalized power in the low frequency (LF) and in the LF/HF ratio, before and after ablation, was statistically significant in both groups (LF/HF 2.6+/-1.6 before vs. 1.4+/-1.7 after ablation in PVI group and LF/HF 3.3+/-2.6 before vs. 1.8+/-1.9 after ablation in the GP group). Relative to heart rate variability parameters, there were no differences between PVI and PVI + plus GP ablation.

Clinical Implications of Unmasking Dormant Conduction After Circumferential Pulmonary Vein Isolation in Atrial Fibrillation Using Adenosine: A Systematic Review and Meta-Analysis

Purpose: Circumferential pulmonary vein isolation (CPVI) is a routine ablation strategy of atrial fibrillation (AF). The adenosine test can be used to unmask dormant conduction (DC) of pulmonary veins after CPVI, thereby demonstrating possible pulmonary vein re-connection and the need for further ablation. However, whether adenosine test could help improve the long term successful rate of CPVI is still controversial. This systemic review and meta-analysis was to determine the clinical utility of the adenosine test.

Methods: PubMed, EMBASE, Web of Science and Cochrane Library database were searched through July 2016 to identify relevant studies using the keywords “dormant pulmonary vein conduction,” “adenosine test,” “circumferential pulmonary vein isolation,” and “atrial fibrillation.” A random-effects model was used to compare pooled outcomes and tested for heterogeneity.

Results: A total of 17 studies including 5,169 participants were included in the final meta-analysis. Two groups of comparisons were classified: (1) Long-term successful rate in those AF patients underwent CPVI with and without adenosine test [Group A (+) and Group A (−)]; (2) Long-term successful rate in those patients who had adenosine test with and without dormant conduction [Group DC (+) and Group DC (−)]. The overall meta-analysis showed that no significant difference can be observed between Group A (+) and Group A (−) (RR 1.08; 95% CI 0.97–1.19; P = 0.16; I² = 66%) and between Group DC (+) and Group DC (−) (RR 1.01; 95% CI 0.91–1.12; P = 0.88; I² = 60%).

Conclusion: Pooled meta-analysis suggested adenosine test may not improve long-term successful rate in AF patients underwent CPVI. Furthermore, AF recurrence may not be decreased by eliminating DC provoked by adenosine, even though adenosine test was applied after CPVI.

Catheter ablation for atrial fibrillation in heart failure with reduced ejection fraction: a systematic review and meta-analysis of randomized controlled trials

Background

Previous randomized controlled trials (RCT)s showed similar outcomes in patients with atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF) treated with anti-arrhythmic drugs (AAD) compared to rate control therapy. We sought to evaluate whether catheter ablation is superior to medical therapy in patients with AF and HFrEF.

Methods

We searched electronic databases for all RCTs that compared catheter ablation and medical therapy (with or without use of AAD). We used random-effects models to summarize the studies. The primary end-point was all-cause mortality. Secondary outcomes included heart failure-related hospitalizations and change in left ventricular ejection fraction (LVEF).

Results

We retrieved and summarized 7 randomized controlled trials, enrolling 856 patients (429 in the catheter ablation arm and 427 in the medical therapy arm). Compared with medical therapy (including use of AAD), AF catheter ablation was associated with a significant reduction in mortality (risk ratio 0.50; 95% confidence interval [CI]: 0.34 to 0.74; P = 0.0005) and heart failure-related hospitalizations (risk ratio 0.56; 95% CI: 0.44 to 0.71; P < 0.0001). Furthermore, catheter ablation led to significant improvements in LVEF (weighted mean difference, 7.48; 95% CI: 3.71 to 11.26; P < 0.0001).

Conclusions

Compared to medical therapy, including use of AAD, catheter ablation for AF was associated with a significant reduction in mortality and heart failure-related hospitalizations as well as an improvement in LVEF in patients with HFrEF. Larger trials are needed to confirm whether rhythm control with ablation is superior to rate control in patients with AF and heart failure.

Clinical impact of insulin resistance on pulmonary vein isolation outcome in patients with paroxysmal atrial fibrillation

INTRODUCTION

The relationship between insulin resistance and atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) remains unclear.

METHODS

Drug-refractory 114 paroxysmal AF patients (89 males, 62 ± 8 years) who underwent successful PVI were enrolled. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated and a value of ≥2.5 was defined as insulin resistant. The left atrial volume index (LAVI) was measured using echocardiography before and 1 year after PVI. Tumor necrosis factor-α (TNF-α) and TGF-β1 serum levels were measured before PVI, and the left atrium (LA) conduction velocity was calculated. The patients were divided into two groups (group 1: HOMA-IR < 2.5, n = 81; group 2: HOMA-IR ≥ 2.5, n = 33).

RESULTS

The LAVI between the two groups before PVI did not significantly differ (P > 0.05), nor did TNF-α (7.7 ± 2.0 vs 7.5 ± 1.0 pg/mL; P = 0.149) or TGF-β1 (28.4 ± 12.0 vs 27.6 ± 10.3 ng/mL; P = 0.757). LAVI before and 1 year after PVI in each group did not change. The conduction velocity of group 2 was slower than that of group 1 (0.7 ± 0.1 vs 1.1 ± 0.3 m/s, P < 0.001). Kaplan-Meier analysis showed significantly higher AF recurrence in group 2 than that in group 1 ( P = 0.019). Cox multivariable analysis revealed that insulin resistance was an independent predictor of recurrence (hazard ratio 1.287, P = 0.004).

CONCLUSION

Our results suggest that insulin resistance promotes LA electrical remodeling and might be related to AF recurrence after PVI.

Impact of Atrial Fibrillation Ablation on Recurrent Hospitalization: A Nationwide Cohort Study

OBJECTIVES

This study assessed the impact of atrial fibrillation (AF) ablation on hospitalization and antiarrhythmic drug use in the community setting.

BACKGROUND

Despite the widespread increase in the use of catheter ablation to treat AF in the United States, the impact of ablation on arrhythmic, cardiovascular, and noncardiovascular hospitalizations remains unclear.

METHODS

The national prospectively acquired Truven Health MarketScan data set (January 1, 2008 to December 31, 2014) was used to identify patients who underwent first time AF ablation with uninterrupted enrollment for 24 months (12 months pre-ablation and 12 months post-ablation). Multivariate logistic regression was used to determine predictors of hospitalization.

RESULTS

Of 5,238 patients who underwent AF ablation for the first time, 2,720 patients with uninterrupted enrollment were analyzed (age 60 ± 10 years; 29% were women, 79% had hypertension, and 23% had heart failure [HF]). AF ablation was associated with significantly reduced all-cause hospitalization from 1,669 hospitalizations in the year before ablation to 1,034 hospitalizations in the year after ablation, which was driven primarily by a 56% reduction in arrhythmic hospitalization. Nonarrhythmic cardiovascular hospitalizations also declined through a 43% drop off in HF hospitalizations. Noncardiovascular hospitalization rates did not significantly change. Age younger than 55 years (odds ratio [OR]: 1.43; p < 0.001), obstructive sleep apnea (OR: 1.38; p < 0.001), and HF (OR: 1.29; p = 0.024) were multivariate predictors for decreased arrhythmic hospitalization. Rates of antiarrhythmic drug use also significantly declined post-procedure by 37.5% (p < 0.001).

CONCLUSIONS

In this nationwide cohort, AF ablation was associated with significant decreases in arrhythmic and nonarrhythmic cardiovascular hospitalizations, which was driven by reductions in hospitalization for AF and HF.

A randomized clinical trial of early invasive intervention for atrial fibrillation (EARLY-AF) - methods and rationale

BACKGROUND

The ideal management of patients with newly diagnosed symptomatic atrial fibrillation (AF) remains unknown. Current practice guidelines recommend a trial of antiarrhythmic drugs (AAD) prior to considering an invasive ablation procedure. However, earlier ablation offers an opportunity to halt the progressive patho-anatomical changes associated with AF, as well as impart other important clinical benefits.

OBJECTIVE

The aim of this study is to determine the optimal initial management strategy for patients with newly diagnosed, symptomatic atrial fibrillation.

METHODS/DESIGN

The EARLY-AF study (ClinicalTrials.govNCT02825979) is a prospective, open label, multicenter, randomized trial with a blinded assessment of outcomes. A total of 298 patients will be randomized in a 1:1 fashion to first-line AAD therapy, or first-line cryoballoon-based pulmonary vein isolation. Patients with symptomatic treatment naïve AF will be included. Arrhythmia outcomes will be assessed by implantable cardiac monitor (ICM). The primary outcome is time to first recurrence of AF, atrial flutter, or atrial tachycardia (AF/AFL/AT) between days 91 and 365 following AAD initiation or AF ablation. Secondary outcomes include arrhythmia burden, quality of life, and healthcare utilization.

DISCUSSION

The EARLY-AF study is a randomized trial designed to evaluate the optimal first management approach for patients with AF. We hypothesize that catheter ablation will be superior to drug therapy in prevention of AF recurrence.

Efficacy of temperature-guided cryoballoon ablation without using real-time recordings - 12-Month follow-up

Background

We sought to evaluate a temperature-guided approach of cryoballoon (CB) ablation without visualization of real-time recordings.

Methods and results

We analysed 166 patients (34.9% female, 60 ± 11 years) with paroxysmal or short-term persistent atrial fibrillation (AF). Comorbidities included diabetes mellitus (n = 28), coronary artery disease (n = 24), hypertension (n = 122), previous stroke or TIA > 3 months (n = 12). Cryoablation of the pulmonary veins (PV) was performed using first-generation (n = 78) and second-generation CB (n = 88). Two 5-minute freezes were performed for the first-generation and two 4-minute freezes for the second-generation CB with the intention to achieve a temperature drop below −40 °C. At 12-month follow-up, we observed overall freedom from AF in 92 patients (56.6%, mean time to AF recurrence 3.4 ± 2.9 months). There was a significant difference in freedom from AF between first-generation CB (45%) and second-generation CB (67%; p < 0.005). Complications were groin hematoma (4.8%) and phrenic nerve palsy (PVP) (2.4%). PVP disappeared after 12 months in all patients. Three patients developed cardiac tamponade (1.8%) that resolved without further sequelae after pericardiocentesis. Multivariate analysis revealed that only the achieved temperature in the right inferior PV (RIPV) was a predictor of long-term freedom from AF (OR 0.9; p = 0.014). Female gender was a predictor of AF recurrence (OR 6.1; p = 0.022).

Conclusion

Temperature-guided CB ablation without real-time recordings is feasible and safe without reducing the efficacy if second-generation CB is used. Deep nadir temperatures especially in the RIPV are necessary for long term-success.

Percutaneous versus thoracoscopic ablation of symptomatic paroxysmal atrial fibrillation: a randomised controlled trial - the FAST II study

BACKGROUND

The most efficient first-time invasive treatment, for achieving sinus rhythm, in symptomatic paroxysmal atrial fibrillation has not been established. We aimed to compare percutaneous catheter and video-assisted thoracoscopic pulmonary vein radiofrequency ablation in patients referred for first-time invasive treatment due to symptomatic paroxysmal atrial fibrillation. The primary outcome of interest was the prevalence of atrial fibrillation with and without anti-arrhythmic drugs at 12 months.

METHODS

Ninety patients were planned to be randomised to either video-assisted thoracoscopic radiofrequency pulmonary vein ablation with concomitant left atrial appendage excision or percutaneous catheter pulmonary vein ablation. Episodes of atrial fibrillation were defined as more than 30 s of atrial fibrillation observed on Holter monitoring/telemetry or clinical episodes documented by ECG.

RESULTS

The study was terminated prematurely due to a lack of eligible patients. Only 21 patients were randomised and treated according to the study protocol. Thoracoscopic pulmonary vein ablation was performed in 10 patients, and 11 patients were treated with catheter ablation. The absence of atrial fibrillation without the use of anti-arrhythmic drugs throughout the follow-up was observed in 70% of patients following thoracoscopic pulmonary vein ablation and 18% after catheter ablation (p < 0.03).

CONCLUSION

Thoracoscopic pulmonary vein ablation may be superior to catheter ablation for first-time invasive treatment of symptomatic paroxysmal atrial fibrillation with regard to obtaining sinus rhythm off anti-arrhythmic drugs 12 months postoperative.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01336075 . Registered April 15th, 2011.

The trend of change in catheter ablation versus antiarrhythmic drugs for the management of atrial fibrillation over time: a meta-analysis and meta-regression

Objective

To evaluate the trend of change in the efficacy and safety of catheter ablation compared with antiarrhythmic drug therapy (ADT) for rhythm control in patients with atrial fibrillation (AF) over time.

Methods

The online databases PubMed and EMBASE were searched for relevant studies. STATA software (version 12.0) was used to perform the meta-analysis and meta-regression.

Results

Fifteen randomized controlled trials including 2249 patients with AF were identified. The pooled results showed that catheter ablation was associated with a 52% reduction in the risk of AF recurrence compared with ADT [risk ratio (RR) = 0.48, 95% confidence interval (CI): 0.40–0.57, I² = 70.7%). Subgroup analyses showed that catheter ablation exhibited less efficacy in studies after 2011 compared to studies before 2011 (RR = 0.61, 95% CI: 0.54–0.68, I² = 9.3% and RR = 0.34, 95% CI: 0.24–0.47, I² = 69.9%, respectively), and the safety outcome showed a 1.08-fold higher incidence of adverse events (14.2% vs. 7.3%; RR = 1.08, 95% CI: 1.04–1.13) in studies after 2011.

Conclusions

Catheter ablation appears to be superior to ADT for rhythm control. However, less efficacy and a higher rate of adverse events were observed in studies after 2011 compared to studies before 2011.

Comparison of two modes of long-term ECG monitoring to assess the efficacy of catheter ablation for paroxysmal atrial fibrillation

AIMS

Optimal ECG monitoring in detecting recurrences of atrial fibrillation (AF) or atrial tachycardia (AT) after catheter ablation has not been well established. The purpose of this prospective study was to compare the utility of daily ECG monitoring with episodic card recorder (ECR) vs. periodic monitoring with episodic loop recorder (ELR) for the detection of post-blanking AF/AT recurrences during early (Months 4-6) and late (Months 7-12) periods after catheter ablation for paroxysmal AF.

METHODS

The study included 105 consecutive patients, who received ECR for 12 months and were instructed to send at least 2 random ECG recordings daily with extra-recordings during symptoms. The patients were simultaneously monitored for one week with ELR at the end of each period (Months 6 and 12).

RESULTS

Thirty-one and 12 patients with AF/AT recurrence were identified by means of ECR and ELR, respectively. In patients with complete and valid data, ELR technology was inferior to ECR by detecting AF/AT in 5 (31%) of 16 and 5 (26%) of 19 patients with arrhythmia identified by ECR in the early and late period, respectively. Overall, ELR had a sensitivity of 8/23 (35%) for detecting AF/AT recurrence. There was no single patient with AF/AT recurrence on ELR that would not be known from ECR monitoring. Only 2 patients with arrhythmia recurrence were completely asymptomatic throughout the study period.

CONCLUSION

Daily ECG monitoring with ECR was better than periodic monitoring with ELR in detecting AF/AT recurrences during the follow-up periods. Entirely asymptomatic patients with AF/AT recurrences were rare.