Effect of catheter ablation versus antiarrhythmic drugs on atrial fibrillation: A meta-analysis of randomized controlled trials

Efficacy of sacubitril-valsartan vs. angiotensin-converting enzyme inhibitors or angiotensin receptor blockers in preventing atrial fibrillation recurrence after catheter ablation: a systematic review and meta-analysis

BACKGROUND

Patients who have undergone catheter ablation for atrial fibrillation (AF) may experience recurrence of this condition. The efficacy of sacubitril-valsartan (S/V) in preventing AF recurrence compared with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) is not established. This meta-analysis aimed to establish the best therapeutic choice for preventing AF recurrence after catheter ablation.

METHOD

A systematic search of the PubMed, Embase, and Cochrane databases was conducted for randomized controlled trials (RCTs) and observational studies comparing the use of S/V with ACEI/ARB in patients who underwent catheter ablation. Results are presented as mean difference (MD) with 95% confidence interval (CI). Heterogeneity was assessed with the I2 statistic, and outcomes are expressed as relative risk (RR). R software version 4.2.3 was used for the analysis.

RESULTS

Three RCTs and one cohort study, comprising 642 patients with 319 patients in the S/V group and 323 in the control group, were included. Follow-up ranged from 6 to 36 months, with mean ages ranging from 58.9 to 65.8 years. A significant reduction in persistent AF occurrence was demonstrated favoring the S/V group (RR: 0.54; 95% CI: [0.41, 0.70]; p = 0.000004; I2: 80%) over the ACEI/ARB group. There was no significant difference in left ventricular ejection fraction with S/V use (MD: 1.23; 95% CI: [-0.12, 2.60]; p = 0.076; I2: 0%) compared with ACEI/ARB. The analysis also showed a significant reduction in left atrial volume index (MD: -5.33; 95% CI: [-8.76, -1.90]; p = 0.002; I2: 57%) in the S/V group compared with the ACEI/ARB group.

CONCLUSION

This meta-analysis demonstrated the efficacy of S/V in reducing the incidence of AF in patients undergoing catheter ablation compared with the use of ACEI/ARB. However, more RCTs are needed for a comprehensive evaluation of its efficacy in reducing AF recurrence after catheter ablation in clinical practice.

High-density lipoprotein cholesterol to c-reactive protein ratio predicts atrial fibrillation recurrence after electrical cardioversion

Atrial fibrillation (AF) recurrence after cardioversion is common, and inflammation plays a critical role in its pathophysiology. We aimed to elucidate the predictive role of the ratio of high-density lipoprotein cholesterol to c-reactive protein (HDL-C/CRP) as an inflammatory marker in AF recurrence after electrical cardioversion (ECV). We analyzed patients who underwent elective ECV for atrial fibrillation between June 2020 and December 2023. Baseline levels of HDL-C and CRP were obtained. Ninety-six patients were included. The median age was 59 years, and 48% were female. Atrial fibrillation recurred after ECV in 56 patients (58%). In the AF recurrence group, CHA2DS2-VASc score was higher (2 [1-3] vs. 1[0-2]; p = 0.013), left atrial diameter was larger (43 ± 5 vs. 40 ± 6 mm; p = 0.015), and HDL-C/CRP ratio was lower (5.6 [2.7-13.0] vs. 14.0 [4.8-38.0]; p = 0.003) compared with the sinus rhythm group. Cox regression analysis showed that HDL-C/CRP was a predictor of AF recurrence at follow-up (unadjusted HR = 0.97; CI 95%: 0.95-0.99; p = 0.004; adjusted HR = 0.98; CI 95%: 0.96-0.99; p = 0.030). ROC curve showed that HDL-C/CRP ratio was able to predict AF recurrence after ECV (AUC = 0.68; p = 0.003). Kaplan-Meier analysis showed that patients with baseline HDL-C/CRP <7.4 had higher AF recurrence (log-rank test p = 0.013). Our research demonstrated that the lower HDL-C/CRP ratio predicted AF recurrence after ECV during follow-up.

Decoding the evidence: A synopsis of indications and evidence for catheter ablation in atrial fibrillation (Review)

The present study reviews the role of catheter ablation (CA) in the management of atrial fibrillation (AF), a widespread arrhythmia associated with increased morbidity and mortality. The present review explores current indications and recent evidence supporting CA, assessing patient outcomes and identifying common complications associated with the procedure. Emphasis is placed on optimizing risk factors prior to ablation, including weight control and hypertension management, as these measures can significantly enhance post-procedural outcomes. The present review also discusses the use of antiarrhythmic and anticoagulant therapies following CA to minimize recurrence and reduce stroke risk. Additionally, the cost-effectiveness of CA is discussed, comparing its long-term economic impact with that of medical therapy alone. The present comprehensive review provides insight into best practices for AF management, supporting CA as a promising approach when integrated with targeted lifestyle modifications and pharmacological support for improved, patient-centered outcomes.

Atrial Fibrillation Types and Chronic Kidney Disease are Independent Predictors of Atrial Fibrillation Recurrence After Radiofrequency Ablation

Purpose

Atrial fibrillation (AF) is classified into paroxysmal, persistent, long-term persistent, and permanent types. It is commonly treated by radiofrequency ablation (RFA), which is more successful than conventional anti-arrhythmic drugs, but it is still largely unknown whether these beneficial effects are equally present for all AF types. Here, we evaluated the impact that AF type has on post-RFA patient conditions and identified underlying factors affecting AF prognoses.

Patients and Methods

Three hundred and twenty-nine AF patients who underwent RFA were retrospectively examined (221 paroxysmal, 56 persistent, 52 long-term persistent), during a post-RFA follow-up period, from 3-months to 2-years. Cardiac functional parameters, such as left atrial (LA), ventricular (LV), and pulmonary artery diameters, as well as ejection fraction (EF) and end-diastolic/systolic diameter ratio, were measured using echocardiography. Additionally, chronic kidney disease (CKD) was diagnosed among these AF patients, using the Modification of Diet in Renal Disease (MDRD) formula, and its impact on post-RFA patient outcomes was examined. Logistic regression analysis identified differences between AF and non-AF recurrence groups.

Results

In terms of functional parameters, persistent AF had significantly smaller LA, and larger EF, compared to paroxysmal and long-term persistent groups, while paroxysmal had significantly larger LV versus persistent and long-term persistent after RFA. For post-RFA patient conditions, paroxysmal, compared to persistent and long-term persistent, had significantly lower AF recurrence (18.10% versus 30.36% and 36.54%) and re-hospitalization rates (6.79% versus 14.29% and 19.23%); however, no significant difference was present between the 3 groups in terms of post-operative stroke rates, as well as re-hospitalization duration. Additionally, CKD patients, versus non-CKD, were more prone to AF recurrence and re-hospitalization, being 3.268 times more likely.

Conclusion

AF types and CKD were independent factors influencing AF recurrence, serving as highly sensitive predictors to monitor prognoses and guide treatments. Therefore, personalized treatment regimens should be recommended for different AF patients.

Antiarrhythmic drug therapy and catheter ablation in patients with paroxysmal or persistent atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

Catheter ablation and antiarrhythmic drug therapy are utilized for rhythm control in atrial fibrillation (AF), but their comparative effectiveness, especially with contemporary treatment modalities, remains undefined. We conducted a systematic review and meta-analysis contrasting current ablation techniques against antiarrhythmic medications for AF.

METHODS

We searched PubMed, SCOPUS, Cochrane CENTRAL, and Web of Science until November 2023 for randomized trials comparing AF catheter ablation with antiarrhythmics, against antiarrhythmic drug therapy alone, reporting outcomes for > 6 months. Four investigators extracted data and appraised risk of bias (ROB) with ROB 2 tool. Meta-analyses estimated pooled efficacy and safety outcomes using R software.

RESULTS

Twelve trials (n = 3977) met the inclusion criteria. Catheter ablation was associated with lower AF recurrence (relative risk (RR) = 0.44, 95%CI (0.33, 0.59), P ˂ 0.0001) and hospitalizations (RR = 0.44, 95%CI (0.23, 0.82), P = 0.009) than antiarrhythmic medications. Catheter ablation also improved the physical quality of life component score (assessed by a 36-item Short Form survey) by 7.61 points (95%CI -0.70-15.92, P = 0.07); but, due to high heterogeneity, it was not statistically significant. Ablation was significantly associated with higher procedural-related complications [RR = 15.70, 95%CI (4.53, 54.38), P < 0.0001] and cardiac tamponade [RR = 9.22, 95%CI (2.16, 39.40), P = 0.0027]. All-cause mortality was similar between the two groups.

CONCLUSIONS

For symptomatic AF, upfront catheter ablation reduces arrhythmia and hospitalizations better than continued medical therapy alone, albeit with moderately more adverse events. Careful patient selection and risk-benefit assessment are warranted regarding the timing of ablation.

Bilirubin Elevation During Hospitalization Post Radiofrequency Catheter Ablation of Persistent Atrial Fibrillation: Variation Trend, Related Factors, and Relevance to 1-Year Recurrence

Background

The role of total bilirubin (TBIL) in cardiovascular disease has been increasingly recognized in recent decades. Studies have shown a correlation between total bilirubin levels and the prognosis of patients after heart surgery. This study aimed to investigate the clinical significance of bilirubin elevation in persistent atrial fibrillation (PAF) patients who received radiofrequency catheter ablation (RFCA).

Methods and Results

A total of 184 patients with PAF who received RFCA were retrospectively studied. Laboratory examinations and demographic data were analyzed to identify independent predictors of TBIL elevation. The relationship between TBIL and prognosis was further investigated. Our results indicated that TBIL increased significantly after RFCA. Multiple linear regression analysis showed that TBIL elevation owned a negative correlation with the percentile of low voltage areas (LVAs) in left atria (β=-0.490, P<0.001). In contrast, a positive correlation was observed with the white blood cell (WBC) ratio (β=0.153, P=0.042) and left atrial diameter (LAD) (β=0.232, P=0.025). It was found that postoperative TBIL levels increased and then gradually decreased to baseline within 5 days without intervention. The bilirubin ratio <1.211 indicated the possibility of 1-year AF recurrence after ablation with a predictive value of 0.743 (specificity = 75.00%, sensitivity = 66.67%).

Conclusion

Bilirubin elevation post PAF RFCA was a common phenomenon and was associated with 1-year recurrence of AF in PAF patients after RFCA.

Wound incidence and outcomes in atrial fibrillation: Comparing catheter ablation and anti-arrhythmic drug therapy

The most prevalent form of cardiac arrhythmia is atrial fibrillation (AF), which is typically managed through catheter ablation or anti-arrhythmic drug therapy. We compared the incidence and outcomes of wound complications in patients with atrial fibrillation who were treated with catheter ablation as opposed to anti-arrhythmic drug therapy. From May to November 2023, 240 adult AF patients who were treated with catheter ablation or anti-arrhythmic medications participated in a 6-month retrospective cohort study at Sir Run Run Shaw Hospital in Hangzhou, China. An observation was made regarding 29 wound complications out of 240 patients. In comparison to drug therapy group, incidence of minor (8 vs. 11) and total complications (18 vs. 11) was greater in catheter ablation group. Significant adverse events occurred at higher rate in the catheter ablation group (6 versus 1) (p < 0.05). However, despite these patterns, there was no statistically significant difference in the rates of complications (total: p = 0.245; minor: p = 0.217; major: p = 0.128). Comparable treatment efficacy was observed across groups. In contrast to drug therapy, catheter ablation was associated with decreased probability of complications (odds ratio: 0.86), as determined by logistic regression; cardiac failure was a significant predictor of adverse outcomes. The study concluded that the risks of wound complications associated with catheter ablation and anti-arrhythmic drug therapy in patients with atrial fibrillation are comparable. Notwithstanding an elevated propensity for complications in ablation group, the statistical analysis indicated comparable safety profiles.

Catheter ablation versus medical therapy in atrial fibrillation: an umbrella review of meta-analyses of randomized clinical trials

This umbrella review synthesizes data from 17 meta-analyses investigating the comparative outcomes of catheter ablation (CA) and medical treatment (MT) for atrial fibrillation (AF). Outcomes assessed were mortality, risk of hospitalization, AF recurrence, cardiovascular events, pulmonary vein stenosis, major bleeding, and changes in left ventricular ejection fraction (LVEF) and MLHFQ score. The findings indicate that CA significantly reduces overall mortality and cardiovascular hospitalization with high strength of evidence. The risk of AF recurrence was notably lower with CA, with moderate strength of evidence. Two associations reported an increased risk of pulmonary vein stenosis and major bleeding with CA, supported by high strength of evidence. Improved LVEF and a positive change in MLHFQ were also associated with CA. Among patients with AF and heart failure, CA appears superior to MT for reducing mortality, improving LVEF, and reducing cardiovascular rehospitalizations. In nonspecific populations, CA reduced mortality and improved LVEF but had higher complication rates. Our findings suggest that CA might offer significant benefits in managing AF, particularly in patients with heart failure. However, the risk of complications, including pulmonary vein stenosis and major bleeding, is notable. Further research in understudied populations may help refine these conclusions.

Safety and efficacy of direct oral anticoagulation in patients with and without radiofrequency ablation of non-valvular atrial fibrillation: a multicenter retrospective cohort study

BACKGROUND

Based on the few available studies on the prognostic benefit of using direct oral anticoagulants (DOACs) after atrial fibrillation (AF) ablation. Therefore, this study aimed to evaluate the prognostic differences between patients who underwent radiofrequency ablation (RFA) and those without RFA taking DOACs.

METHODS

This is a multicenter retrospective cohort study enrolling 6137 patients with non-valvular AF (NVAF) at 15 hospitals in China. Patient information was collected through a mean follow-up of 10 months and medical record queries. Clinical outcomes included major bleeding, total bleeding, thrombosis, all-cause death, and a composite endpoint of bleeding, thrombosis, and all-cause death.

RESULTS

After adjusting for confounders and propensity score matching (PSM), patients with RFA of NVAF had a significantly lower risk of major bleeding [OR 0.278 (95% CI, 0.150-0.515), P<0.001], thrombosis [OR 0.535 (95% CI, 0.316-0.908), P=0.020] and the composite endpoint [ OR 0.835 (95% CI, 0.710-0.982), P=0.029]. In the RFA PSM cohort, dabigatran was associated with reduced all-cause death in patients with RFA of NVAF [OR 0.420 (95% CI, 0.212-0.831), P=0.010]. In the no RFA PSM cohort, rivaroxaban was associated with a reduction in major bleeding [OR 0.521 (95% CI, 0.403-0.673), P<0.001], total bleeding [OR 0.114 (95% CI, 0.049-0.266), P<0.001], and the composite endpoint [OR 0.659 ( 95% CI, 0.535-0.811), P<0.001].

CONCLUSION

Among patients with NVAF treated with DOACs, RFA was a negative correlate of major bleeding, thrombosis, and composite endpoints but was not associated with total bleeding or all-cause mortality.

Impact of redo ablation for atrial fibrillation on patient-reported outcomes and quality of life

INTRODUCTION

Catheter ablation for atrial fibrillation (AF) is frequently used for the purpose of rhythm control and improved quality of life (QoL). Although success rates are high, a significant proportion of patients require redo ablation. Data are scarce on patient-centered outcomes and QoL in patients undergoing redo AF ablation. We aimed to assess QoL and clinical outcomes using a large prospectively maintained patient-reported outcomes (PRO) registry.

METHODS

All patients undergoing redo AF ablation (2013-2016) at our center were enrolled in a prospective registry for outcomes and assessed for QoL using automated PRO surveys (baseline, 3 and 6 months after ablation, every 6 months thereafter). Data were collected over 3 years of follow-up. The atrial fibrillation symptom severity scale (AFSSS) was used as the main measure for QoL. Additional variables included patient-reported improvement, AF burden, and AF-related healthcare utilization including emergency room (ER) visits and hospitalizations.

RESULTS

A total of 848 patients were included (28% females, mean age 63.8, 51% persistent AF). By automated PRO, significant improvement in QoL was noted (baseline median AFSSS of 12 [5-18] and ranged between 2 and 4 on subsequent assessments; p < .0001), with ≥70%of patients reported remarkable improvement in their AF-related symptoms. The proportion of patients in AF at the time of baseline survey was 36%, and this decreased to <8% across all time points during follow-up (p < .0001). AF burden was significantly reduced (including frequency and duration of episodes; p < .0001), with an associated decrease in healthcare utilization after 6 months from the time of ablation (including ER visits and hospitalizations; p < .0001). The proportion of patients on anticoagulants or antiarrhythmics decreased on follow-up across all time points (p < .0001 for all variables).

CONCLUSION

Most patients derive significant QoL benefit from redo AF ablation; with reduction of both AF burden and healthcare utilization.

Outcomes of catheter ablation versus antiarrhythmic therapy in patients with atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

Recent data have shown an advantage of rhythm control over rate control for the treatment of atrial fibrillation (AF). Nevertheless, the data regarding efficacy of catheter ablation (CA) compared with antiarrhythmic drugs (AADs) in patients with AF is lacking. Therefore, we sought to evaluate recurrence of arrhythmia, all-cause mortality, cardiovascular deaths, stroke/TIA, and all-cause readmissions of CA compared with AAD in patients with AF.

METHODS

Systematically searched through PubMed, Google Scholar, EMBASE, and Cochrane for randomized control trials that compared CA and AAD in atrial fibrillation patients. Review Manager 5.4 and OpenMetaAnalyst were used to analyze the data. Data was pooled for the outcomes using random-effect models (DerSimonian and Laird) and reported as pooled odds ratio (OR).

RESULTS

A total of 4822 patients were included. The CA group had 2417 patients while the AAD group included 2405 patients. Pooled data demonstrated that the CA arm had a statistically significant decrease in risk for recurrence of arrhythmia as compared to AAD (OR 0.25; [95% CI, 0.18-0.36]; p < 0.001). All-cause readmission was statistically significantly lower in CA as compared to AAD (OR 0.33; [95%CI, 0.17-0.63]; p < 0.001). For other secondary outcomes, there was no statistically significant difference between CA and AAD with regard to all-cause mortality (OR 0.75; [95% CI, 0.55-1.03]), cardiovascular death (OR 0.76; [95% CI, 0.22-2.54]), bleeding (OR 1.09, [95% CI 0.74, 1.61]), or stroke/TIA outcome (OR 0.90, [95% CI, 0.59-1.37]).

CONCLUSIONS

In this study of pooled data from 16 RCTs, CA utilization for atrial fibrillation had improved freedom from arrhythmia as well as reduced all-cause readmission compared with AAD.

Herzinsuffizienz und Vorhofflimmern – eine Zwillingsepidemie

Vorhofflimmern (VHF) und eine Herzinsuffizienz begünstigen sich gegenseitig und treten häufig in Kombination auf. Eine effektive Therapie des VHF inklusive der möglicherweise notwendigen Antikoagulation sollte zentraler Baustein bei Patienten mit eingeschränkter systolischer Funktion und VHF sein. Medikamentöse Therapieoptionen sind in der Regel wenig effektiv, sodass zunehmend Katheterablationsverfahren zur Behandlung dieser Patienten in den Vordergrund gestellt werden. Randomisierte Studien bei selektierten Patienten zeigen nicht nur einen symptomatischen Effekt auf die Herzinsuffizienz, sondern neben Verbesserung der LV-Funktion auch einen Letalitätsbenefit der effektiven Ablation von VHF. In der Zukunft gilt es, Patienten sinnvoll für die Katheterablation zu identifizieren. Ob das reine Vorhandensein von VHF oder eher die VHF-Last bei Patienten mit Herzinsuffizienz entscheidend für die Prognose ist, wird aktuell in weiteren Studien untersucht.

Impact of early ablation of atrial fibrillation on long-term outcomes: results from phase II/III of the GLORIA-AF registry

Background

First-line ablation for atrial fibrillation (AF) reduces the risk of recurrent atrial arrhythmias compared to medical therapy. However, the prognostic benefit of early AF ablation remains undetermined. Herein, we aimed to evaluate the effects of early AF ablation compared to medical therapy.

Methods

Using data from phase II/III of the GLORIA-AF registry, we studied patients who were consecutively enrolled with newly diagnosed AF (< 3 months before baseline visit) and an increased risk of stroke (CHA₂DS₂–VASc ≥ 1). At baseline visit, 445 (1.7%) patients were treated with early AF ablation and 25,518 (98.3%) with medical therapy. Outcomes of interest were the composite outcome of all-cause death, stroke and major bleeding, and pre-specified outcomes of all-cause death, cardiovascular (CV) death, non-CV death, stroke and major bleeding.

Results

A total of 25,963 patients (11733 [45.2%] females; median age 71 [IQR 64–78] years; 17424 [67.1%] taking non-vitamin K antagonist oral anticoagulants [NOACs]) were included. Over a follow-up period of 3.0 (IQR 2.3–3.1) years, after adjustment for confounders, early AF ablation was associated with a significant reduction in the composite outcome of all-cause death, stroke and major bleeding (HR 0.50 [95% CI 0.30–0.85]) and all-cause death (HR 0.45 [95% CI 0.23–0.91]). There were no statistical differences between the groups in terms of CV death, non-CV death, stroke and major bleeding. Similar results were obtained in a propensity-score matched analysis of patients with comparable baseline variables.

Conclusions

Early AF ablation in a contemporary prospective cohort of AF patients who were predominantly treated with NOACs was associated with a survival advantage compared to medical therapy alone.

Trial registration

Clinical trial registration: http://www.clinicaltrials.gov. Unique identifiers: NCT01468701, NCT01671007 and NCT01937377.

Graphical abstract

Created with BioRender.com.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-022-02022-1.

Sacubitril/valsartan attenuates atrial structural remodelling in atrial fibrillation patients

Aims

Radiofrequency catheter ablation (RFCA) is now an established therapeutic option for patients with atrial fibrillation (AF), but the long‐term recurrence rate of AF is still high. Sacubitril/valsartan (Sac/Val) is superior to valsartan in attenuating ventricular remodelling and improving clinical outcomes in heart failure patients, but whether this additional benefit exists in reversing atrial remodelling and reducing AF recurrence of RFCA‐treated AF patients remains uncovered.

Methods and results

Patients that had undergone RFCA were enrolled and randomly assigned 1:1 to valsartan (160 mg/day) or Sac/Val (200 mg/day) treatment group, in addition to other standard treatment of AF. Patients were followed up for 24 weeks. Echocardiography and ambulatory Holter monitoring for 24 h was performed at 24 weeks after RFCA. The primary end point was the change of atrial diameter from baseline to 24 weeks after RFCA. Second end points included the recurrence rate of AF, all‐cause hospitalization and all‐cause death. A total of 64 AF patients were enrolled, 32 of which received Sac/Val and 32 received valsartan treatment. There was no difference in the age (64.8 ± 9.8 vs. 63.7 ± 9.0, P = 0.634), gender (per cent of male: 59.4% vs. 50.0%, P = 0.616), heart rate (84.7 ± 4.1 b.p.m. vs. 80.9 ± 2.6 b.p.m., P = 0.428), systolic (127.5 ± 15.4 mmHg vs. 130.0 ± 17.8 mmHg, P = 0.549) or diastolic (81.7 ± 9.8 mmHg vs. 79.9 ± 12.6, P = 0.537) blood pressure upon admission between valsartan and Sac/Val treatment groups. The percentage of persistent AF was also comparable (43.8% vs. 53.1%, P = 0.617) in both treatment groups. Patients receiving Sac/Val treatment displayed significant decrease in the left atrial diameter (4.3 ± 0.5 cm to 3.8 ± 0.5 cm, P < 0.001), volume index (48.0 ± 6.4 mL/m² to 41.7 ± 7.0 mL/m², P < 0.001), and right atrial diameter (4.4 ± 0.8 cm to 3.9 ± 0.7 cm, P = 0.017) from baseline to 24 weeks after RFCA. This effect was not observed in valsartan treatment group. There was a numerical decrease in AF recurrence rate in the Sac/Val group compared with valsartan group (9.4% vs. 15.6%), although this difference did not reach a statistical significance (P = 0.708). No difference in all‐cause hospitalization rate (6.3% in each group) or all‐cause death rate (0% in each group) was observed.

Conclusions

Our data indicate that Sac/Val is superior to valsartan in attenuating atrial structural remodelling in catheter ablation‐treated AF patients.

Impact of low-level electromagnetic fields on the inducibility of atrial fibrillation in the electrophysiology laboratory

Background

Atrial fibrillation (AF) is the most common sustained arrhythmia in adults. Research suggests that autonomic nervous (ANS) system dysfunction contributes to AF pathophysiology. Animal studies have shown that low-level electromagnetic fields (LL-EMF) are potentially capable of AF suppression. This study evaluated the safety and efficacy of LL-EMF in suppressing AF in humans.

Objective

To investigate the impact of LL-EMF on AF inducibility in humans.

Methods

Patients presenting for ablation of paroxysmal AF were randomized to a sham protocol or LL-EMF (3.2 × 10^-8 G at 0.89 Hz) applied via a Helmholtz coil around the head. AF was induced via atrial pacing, and was cardioverted if duration was greater than 15 minutes. The protocol was then run for 60 minutes, followed by reinduction of AF. The primary endpoint was the duration of pacing-induced AF after protocol completion compared between groups.

Results

Eighteen patients completed the study protocol (n = 10 sham, n = 8 LL-EMF). Pacing-induced AF duration in the LL-EMF group was 11.0 ± 3.43 minutes shorter than control after protocol completion (CI 3.72–18.28 minutes, P = .03). A smaller proportion of LL-EMF patients experienced spontaneous firing initiating an AF episode (0/7 vs 5/6, P = .0047). A significantly greater proportion of patients in the control group required direct current cardioversion after 1 hour (0.78 vs 0.13, P = .02).

Conclusion

In patients with paroxysmal AF, LL-EMF stimulation results in shorter episodes of pacing-induced AF and a reduced likelihood of spontaneous firing initiating an episode of AF.

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.

Surgical Treatment of Atrial Fibrillation: Cutting Through the Edges

Medical management of atrial fibrillation can be complex, challenging and requiring time to prove its effectiveness; furthermore, the response can be refractory and inconsistent if the underlying pathology is not permanently addressed. Surgical ablation has become a key intervention, and since its first intervention in 1987 (the Cox-maze procedure), the technique has evolved from a conventional open method to a minimally invasive technique whilst retaining excellent outcomes. Furthermore, recent advances in the use of a hybrid approach have been established as satisfactory approach in managing atrial fibrillation with satisfactory outcomes.

This literature review focuses on the evidence behind the surgical success in managing atrial fibrillation throughout the past, present and the future of these surgical interventions.

Meta-Analysis of Catheter Ablation versus Medical Therapy in Patients with Atrial Fibrillation Without Heart Failure

Introduction

Catheter ablation has shown to reduce mortality in patient with atrial fibrillation (AF) and heart failure (HF) with reduced ejection fraction. Its effect on mortality in patients without HF has not been well elucidated.

Methods

Thirteen randomized controlled trials encompassing 3856 patients were selected using PubMed, Embase and the CENTRAL till April 2019. Estimates were reported as random effects risk ratio (RR) with 95% confidence intervals (CI).

Results

Compared with medical therapy, catheter ablation did not reduce the risk of all-cause mortality (RR, 0.86, 95% CI, 0.62-1.19, P=0.36; I2=0), stroke (RR, 0.55, 95% CI, 0.18-1.66, P=0.29; I2=0), need for cardioversion (RR, 0.84, 95% CI, 0.66-1.08, P=0.17; I2=0) or pacemaker (RR, 0.59, 95% CI, 0.34-1.01, P=0.06; I2=0). However, ablation reduced the RR of cardiac hospitalization (0.37, 95% CI, 0.18-0.77, P=0.01; I2=86), and recurrent atrial arrhythmia (0.46, 95% CI, 0.35-0.60, P<0.001; I2=87). There were non-significant differences among treatment groups with respect to major bleeding (RR, 1.89, 95% CI, 0.59-6.08, P=0.29; I2=15), and pulmonary vein stenosis (RR, 3.00, 95% CI, 0.83-10.87, P=0.09; I2=0), but had significantly higher rates of pericardial tamponade (RR, 4.46, 95 % CI, 1.70-11.72, P<0.001; I2=0).

Conclusions

Catheter ablation did not improve survival compared with medical therapy in patients with AF without HF. Catheter ablation reduced cardiac hospitalization and recurrent atrial arrhythmia at the expense of pericardial tamponade.

Health-Related Quality of Life in Patients With Atrial Fibrillation Treated With Catheter Ablation or Antiarrhythmic Drug Therapy: A Systematic Review and Meta-analysis

Background

Catheter ablation (CA) is performed in patients with atrial fibrillation (AF) to reduce symptoms and improve health-related quality of life (HRQL).

Methods

This systematic review and meta-analysis of randomized controlled trials (RCTs) evaluated CA of any energy modality compared with antiarrhythmic drugs (AADs) using inverse-variance random-effects models. We searched for RCTs reporting HRQL and AF-related symptoms at 3, 6, 12, 24, 48, and 60 months after treatment as well as the number of repeat ablations.

Results

Of 15,878 records, we included 13 RCTs of CA vs AADs for the analyses of HRQL, 7 RCTs for the analyses of AF-related symptoms, and 13 RCTs for the number of repeat ablations. For the HRQL analyses at 3 months, there were significant increases in both the Physical Component Summary score (3 months' standardized mean difference = 0.58 [0.39-0.78]; P < 0.00001, I ² = 6%, 3 trials, n = 443) and the Mental Component Summary score (3 months' standardized mean difference = 0.57 [0.37-0.77]; P < 0.00001, I ² = 0%, 3 trials, n = 443), favouring CA over AADs. These differences were sustained at 12 months but not >24 months after randomization. Similar results were seen for AF-related symptoms. The number of repeat ablations and success rates after procedure varied considerably across trials.

Conclusions

Evidence from few trials suggests that CA improves physical and mental health and AF-related symptoms in the short term, but these benefits decrease with time. More trials, reporting both HRQL and AF-related symptoms, at consistent time points are needed to assess the effectiveness of CA for the treatment of AF.

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.

Far-field contributions in multi-electrodes atrial recordings blur distinction between anatomical and functional reentries and may cause imaginary phase singularities - A computational study

BACKGROUND

Atrial fibrillation (AF) is the most common cardiac arrhythmia and the most important cause of embolic stroke, requiring new technologies for its better understanding and therapies. Recent approaches to map the electrical activity during AF with multi-electrode systems aim at localizing patient-specific ablation targets of reentrant patterns. However, there is a critical need to determine the accuracy of those mapping systems. We performed computer simulations as a numerical approach of systematically evaluating the influence of far-field sources on the electrical recordings and detection of rotors.

METHODS

We constructed 2 computer models of atrial tissue: (i) a 2D sheet model with varying non-active cells area in its center, and (ii) a whole realistic 3D atrial model. Phase maps were built based on the Hilbert transform of the unipolar electrograms recorded by virtual 2D and 3D multi-electrode systems and rotors were tracked through phase singularities detections.

RESULTS

Analysis of electrograms recorded away from the 2D atrial model shows that the larger the distance between an electrode and the tissue model, the stronger the far-field sources contribution to the electrogram is. Importantly, even if an electrode is positioned in contact with the tissue, the electrogram contains significant contributions from distal sources that blur the distinction between anatomical and functional reentries. Moreover, when mapping the 3D atrial model, remote activity generated false phase singularities at locations without local reentrant excitation patterns.

CONCLUSIONS

Far-field contributions to electrograms during AF reduce the accuracy of detecting and interpreting reentrant activity.

2018 Korean Guideline of Atrial Fibrillation Management

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in the general population. The Korean Heart Rhythm Society organized a Korean AF Management Guideline Committee and analyzed all available studies regarding the management of AF, including studies on Korean patients. This guideline is based on recent data of the Korean population and the recent guidelines of the European Society of Cardiology, European Association for Cardio-Thoracic Surgery, American Heart Association, and Asia Pacific Heart Rhythm Society. Expert consensus or guidelines for the optimal management of Korean patients with AF were achieved after a systematic review with intensive discussion. This article provides general principles for appropriate risk stratification and selection of anticoagulation therapy in Korean patients with AF. This guideline deals with optimal stroke prevention, screening, rate and rhythm control, risk factor management, and integrated management of AF.

Atrial Fibrillation in Patients with Heart Failure: Current State and Future Directions

Heart failure affects nearly 26 million people worldwide. Patients with heart failure are frequently affected with atrial fibrillation, and the interrelation between these pathologies is complex. Atrial fibrillation shares the same risk factors as heart failure. Moreover, it is associated with a higher-risk baseline clinical status and higher mortality rates in patients with heart failure. The mechanisms by which atrial fibrillation occurs in a failing heart are incompletely understood, but animal studies suggest they differ from those that occur in a healthy heart. Data suggest that heart failure-induced atrial fibrosis and atrial ionic remodeling are the underlying abnormalities that facilitate atrial fibrillation. Therapeutic considerations for atrial fibrillation in patients with heart failure include risk factor modification and guideline-directed medical therapy, anticoagulation, rate control, and rhythm control. As recommended for atrial fibrillation in the non-failing heart, anticoagulation in patients with heart failure should be guided by a careful estimation of the risk of embolic events versus the risk of hemorrhagic episodes. The decision whether to target a rate-control or rhythm-control strategy is an evolving aspect of management. Currently, both approaches are good medical practice, but recent data suggest that rhythm control, particularly when achieved through catheter ablation, is associated with improved outcomes. A promising field of research is the application of neurohormonal modulation to prevent the creation of the "structural substrate" for atrial fibrillation in the failing heart.

Stroke and Cardiovascular Events After Ablation or Antiarrhythmic Drugs for Treatment of Patients With Atrial Fibrillation

Catheter ablation and antiarrhythmic drugs (AADs) are the most common rhythm-control strategies for atrial fibrillation (AF). Data comparing the rate of stroke and cardiovascular events between the treatment strategies are limited. Therefore, this observational study uses claims data to compare rate of cardiovascular hospitalization and stroke for patients with AF treated with ablation or AADs. Patients in the MarketScan dataset with AF between January 2010 and December 2014 were categorized in the ablation group if an atrial catheter ablation was performed, or in the AAD group if a relevant AAD was prescribed for AF but no ablation was performed. One year of history was required, and the index event was selected as the most recent ablation or AAD prescription closest to January 1, 2013. A 2:1 propensity score match was performed for age, gender, co-morbidities, and total medical cost in the year before index event. Outcomes included thromboembolic event (ischemic stroke, transient ischemic attack, or systemic embolism) and all cardiovascular hospitalizations. Of the 164,639 patients in the AAD group, 29,456 were matched to the 14,728 ablation patients. There were no significant differences in age (64 ± 10 in both groups), gender (58% male), or CHA₂DS₂-VASc score (3.2 ± 1.3). Risk of hospitalization with primary diagnosis of thromboembolic event was 41% greater in the AADs group (p < 0.001), and cardiovascular hospitalizations were 13% more likely (p < 0.001). In conclusion, patients treated with catheter ablation of AF have lower risk of thromboembolic events and cardiovascular hospitalizations than a matched cohort of patients managed with AADs.

Comparison of health-related quality of life in patients with atrial fibrillation treated with catheter ablation or antiarrhythmic drug therapy: a systematic review and meta-analysis protocol

INTRODUCTION

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and causes patients considerable burden; symptoms such as palpitations and dyspnoea are common, leading to frequent emergency room visits. Patients with AF report reduced health-related quality of life (HQOL) compared with the general population; thus, treatments focus on the restoration of sinus rhythm to improve symptoms. Catheter ablation (CA) is a primary treatment strategy to treat AF-related burden in select patient populations; however, repeat procedures are often needed, there is a risk of major complications and the procedure is quite costly in comparison to medical therapy. As the outcomes after CA are mixed, an updated review that synthesises the available literature, on outcomes that matter to patients, is needed so that patients and their healthcare providers can make quality treatment decisions. The purpose of this review protocol is to extend previous findings by systematically analysing randomised controlled trials (RCTs) of CA in patients with AF and using meta-analytic techniques to identify the benefits and risks of CA with respect to HQOL and AF-related symptoms.

METHODS AND ANALYSIS

We will include all RCTs that compare CA with antiarrhythmic drugs, or radiofrequency CA with cryoballoon CA, in patients with paroxysmal or persistent AF. To locate studies we will perform comprehensive electronic database searches from database inception to 4 April 2017, with no language restrictions. We will conduct a quantitative synthesis of the effect of CA on HQOL as well as AF-related symptoms and the number of CA procedures needed for success, using meta-analytic techniques.

ETHICS AND DISSEMINATION

No ethical issues are foreseen and ethical approval is not required given that this is a protocol. The findings of the study will be reported at national and international conferences, and in a peer-reviewed journal using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

TRIAL REGISTRATION NUMBER

In accordance with the guidelines, our systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 6 March 2017 and was last updated on 6 March 2017 (registration number CRD42017057427).

PROTOCOL AMENDMENTS

Any protocol amendments will be documented on the International Prospective Register of Systematic Reviews (PROSPERO) and in the final manuscript and indicated as such.

Atrial fibrillation in women: treatment

Sex-specific differences in the epidemiology, pathophysiology, presentation, prognosis, and treatment of atrial fibrillation (AF) are increasingly recognized. Women with AF generally experience worse symptoms, poorer quality of life, and have higher risk of stroke and death than men with AF. Effective treatment of the arrhythmia in women is critical to reduce the rate of adverse events. We review the current evidence on sex-specific differences in the utilization and outcomes of treatments for AF, including rate-control and rhythm-control strategies, and stroke-prevention therapy. In addition, we provide a critical evaluation of potential disparities and biases in health-care use that might be associated with differences in the outcomes between women and men. We underscore current knowledge gaps that need to be addressed in future studies to improve the management of AF in women. In particular, we suggest several strategies to produce high-quality evidence from randomized clinical trials for women with AF.

Radiofrequency Catheter Ablation Improves the Quality of Life Measured with a Short Form-36 Questionnaire in Atrial Fibrillation Patients: A Systematic Review and Meta-Analysis

BACKGROUND

The main purpose of performing radiofrequency catheter ablation (RFCA) in atrial fibrillation (AF) patients is to improve the quality of life (QoL) and alleviate AF-related symptoms. We aimed to determine the qualitative and quantitative effects of RFCA on the QoL in AF patients.

METHODS

We performed a systemic review and meta-analysis using a random effects model. We searched for the studies that reported the physical component summary score (PCS) and mental component summary score (MCS) of the short form-36, a validated system to assess and quantify the QoL, before and after RFCA in AF patients. PCS and MCS are T-scores with a mean of 50 and standard deviation of 10.

RESULTS

Of the 470 studies identified through systematic search, we included 13 studies for pre-RFCA vs. the post-RFCA analysis and 5 studies for treatment success vs. AF recurrence analyses. In the pre-RFCA vs. post-RFCA analysis, RFCA was associated with a significant increase in both the PCS (weighted mean difference [WMD] = 6.33 [4.81-7.84]; p < 0.001) and MCS (WMD = 7.80 [6.15-9.44]; p < 0.001). The ΔPCS (post-RFCA PCS-pre-RFCA PCS) and ΔMCS values were used for the treatment success vs. AF recurrence analysis. Patients with successful ablation had a higher ΔPCS (WMD = 7.46 [4.44-10.49]; p < 0.001) and ΔMCS (WMD = 7.59 [4.94-10.24]; p < 0.001).

CONCLUSIONS

RFCA is associated with a significant increase in the PCS and MCS in AF patients. Patients without AF recurrence after RFCA had a better improvement in the PCS and MCS than patients who had AF recurrence.