A Randomized Controlled Trial of Catheter Ablation Versus Medical Treatment of Atrial Fibrillation in Heart Failure (The CAMTAF Trial)

Atrial fibrillation and heart failure- results of the CASTLE-AF trial

Congestive Heart Failure (HF) and Atrial Fibrillation (AFIB) often coexist. Catheter ablation is a well-established option for symptomatic AFIB that is resistant to drug therapy in patients with otherwise normal cardiac function. This has been seen in various studies where catheter ablation was associated with positive outcomes in patients with HF. Recently, the study results from the Catheter Ablation versus Standard Conventional Therapy in Patients with Left Ventricular Dysfunction and Atrial Fibrillation (CASTLE-AF) trial were published. After a median follow-up of more than 3 years, patients getting catheter ablation for AFIB had significantly fewer hospital admissions as well as death from worsening HF. In addition, 63% of patients in the ablation group were in sinus rhythm, as compared with 22% of those in the medical-therapy group (P < 0.001). This trial may represent a significant additional therapeutic tool in the clinical prevention and management of cardiovascular mortality and morbidity. While catheter ablation does not eliminate the AFIB per se, it can limit the ventricular rate by eliminating triggers and altering electrophysiological connections in the heart in a similar fashion to rate control anti-arrhythmic drugs. Longer-duration normal sinus rhythm may improve outcomes by means of a number of mechanisms, including greater atrial emptying, all of which translate into improved cardiac output. A better understanding is needed as to why a decrease in density, but not complete elimination of atrial fibrillation, is sufficient for reverse remodelling. It is anticipated that the results of the CASTLE-AF trial will soon be implemented in international guidelines.

Catheter ablation for treatment of patients with atrial fibrillation and heart failure: a meta-analysis of randomized controlled trials

Background

There is a little evidence for the effects of catheter ablation (CA) on hard endpoints in patients with atrial fibrillation (AF) and heart failure (HF).

Methods

PubMed, Embase and Cochrane Library were searched for randomized controlled trials (RCTs) enrolling patients with AF and HF who were assigned to CA, rate control or medical rhythm control groups. This meta-analysis was performed by using random-effect models.

Results

Seven RCTs enrolling 856 participants were included in this meta-analysis. CA reduced the risks of all-cause mortality (risk ratio [RR] 0.52, 95% CI 0.35 to 0.76), HF readmission (RR 0.58, 95% CI 0.46 to 0.66) and the composite of all-cause mortality and HF readmission (RR 0.55, 95% CI 0.47 to 0.66) when compared with control. But there was no significant difference in cerebrovascular accident (RR 0.56, 95% CI 0.23 to 1.36) between two groups. Compared with control, CA was associated with improvement in left ventricular ejection fraction (mean difference [MD] 7.57, 95% CI 3.72 to 11.41), left ventricular end systolic volume (MD -14.51, 95% CI -26.84 to − 2.07), and left ventricular end diastolic volume (MD -3.78, 95% CI -18.51 to 10.96). Patients undergoing CA exhibited increased peak oxygen consumption (MD 3.16, 95% CI 1.09 to 5.23), longer 6-min walk test distance (MD 26.67, 95% CI 12.07 to 41.27), and reduced Minnesota Living with Heart Failure Questionnaire scores (MD -9.49, 95% CI -14.64 to − 4.34) than those in control group. Compared with control, CA was associated with improved New York Heart Association class (MD -0.74, 95% CI -0.83 to − 0.64) and lower B-type natriuretic peptide levels (MD -105.96, 95% CI -230.56 to 19.64).

Conclusions

CA was associated with improved survival, morphologic changes, functional capacity and quality of life relative to control. CA should be considered in patients with AF and HF.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0904-3) contains supplementary material, which is available to authorized users.

Heart Failure With Improved Ejection Fraction: Is it Possible to Escape One's Past?

Among patients with heart failure with reduced ejection fraction, investigators have repeatedly identified a subgroup whose left ventricular ejection fraction and structural remodeling can improve to normal or nearly normal levels with or without medical therapy. This subgroup of patients with "heart failure with improved ejection fraction" has distinct clinical characteristics and a more favorable prognosis compared with patients who continue to have reduced ejection fraction. However, many of these patients also manifest clinical and biochemical signs of incomplete resolution of heart failure pathophysiology and remain at some risk of adverse outcomes, thus indicating that they may not have completely recovered. Although rigorous evidence on managing these patients is sparse, there are several reasons to recommend continuation of heart failure therapies, including device therapies, to prevent clinical deterioration. Notable exceptions to this recommendation may include patients who recover from peripartum cardiomyopathy, fulminant myocarditis, or stress cardiomyopathy, whose excellent long-term prognoses may imply true myocardial recovery. More research on these patients is needed to better understand the mechanisms that lead to improvement in ejection fraction and to guide their clinical management.

Arrhythmia induced cardiomyopathy

Arrhythmia induced cardiomyopathies (AIC) refer to the collective condition of Arrhythmia, Tachycardia, and ectopy-induced Cardiomyopathy. Atrial fibrillation (AF) and heart failure (HF) are modern epidemics that often coexist and exacerbate one another. We aim to provide an overview of the current understanding and evidence for treatment and management in AIC with a particular focus on AF-mediated cardiomyopathy and suggest approaches to recognize, screen, and manage AIC.

Atrial Fibrillation Ablation in Patients with Heart Failure: One Size Does Not Fit All

Atrial fibrillation (AF) is common in patients with heart failure and is associated with poorer clinical outcomes compared with patients with heart failure alone. Recent evidence has challenged previous treatment paradigms in which rate control was considered equivalent to rhythm control in this population. Catheter ablation has emerged as a safe and effective treatment strategy in selected patients and overcomes the issues of limited efficacy and drug toxicities associated with pharmacological rhythm control. Numerous studies have explored the benefits of catheter ablation in patients with heart failure, but these have included heterogeneous patient cohorts and variable ablation strategies. This state-of-the-art review explores the evidence from these trials and examines the need for tailored, patient-specific strategies for AF ablation in patients with heart failure.

Left Atrial Reverse Remodeling After Catheter Ablation of Nonparoxysmal Atrial Fibrillation in Patients With Heart Failure With Reduced Ejection Fraction

The efficacy of catheter ablation (CA) of nonparoxysmal atrial fibrillation (PAF) in patients with left ventricular systolic dysfunction is controversial. We investigated the outcomes of CA for non-PAF in patients with reduced left ventricular ejection fraction (LVEF) and the impact of early left atrial (LA) reverse remodeling on these outcomes. A total of 251 consecutive patients who underwent CA for non-PAF were divided into 2 groups (reduced: preoperative LVEF ≤55%, LVEF: 46.5 ± 8.7%, n = 63; normal: >55%, 65.8 ± 5.8%, n = 188). We analyzed the 4-year atrial fibrillation- or atrial tachycardia (AT)-free survival rate and assessed changes in LVEF, hemodynamics, and LA reverse remodeling at the end of a 90-day blanking period. We also evaluated LA reverse remodeling in patients with and without recurrence. The atrial fibrillation- or AT-free survival rates were similar (reduced vs normal 48% vs 42%, p = 0.32). The reduced group exhibited significant LVEF improvement (before vs after, 46.5 ± 8.7% vs 58.4 ± 11.5%, p<0.001), reduced mitral regurgitation, and spectral tissue Doppler-derived index, and had greater percent maximum left atrial volume reduction (reduced vs normal 25.3 ± 18.2% vs 19.3 ± 16.2%, p = 0.014). Percent maximum left atrial volume reduction was greater in patients without recurrence (with recurrence vs without recurrence 17.3 ± 16.7% vs 25.4 ± 16.1%, p<0.001). In conclusion, the efficacy of non-PAF CA in patients with reduced LVEF was comparable with that in patients with normal LVEF. Greater LA reverse remodeling in these patients suggests an association with a reduced recurrence rate.

Treatment Strategies for Atrial Fibrillation With Left Ventricular Systolic Dysfunction - Meta-Analysis

BACKGROUND

Atrial fibrillation (AF) frequently coexists with heart failure (HF) with reduced ejection fraction (EF). This meta-analysis compared AF control strategies, that is, rhythm vs. rate, and catheter ablation (CA) vs. anti-arrhythmic drugs (AAD) in patients with AF combined with HF.Methods and Results:The MEDLINE, EMBASE, and CENTRAL databases were searched, and 13 articles from 11 randomized controlled trials with 5,256 patients were included in this meta-analysis. The outcomes were echocardiographic parameters (left ventricular EF, LVEF), left atrial (LA) size, and left ventricular end-systolic volume, LVESV), clinical outcomes (mortality, hospitalization, and thromboembolism), exercise capacity, and quality of life (QOL). In a random effects model, rhythm control was associated with higher LVEF, better exercise capacity, and better QOL than the rate control. When the 2 different rhythm control strategies were compared (CA vs. AAD), the CA group had significantly decreased LA size and LVESV, and improved LVEF and 6-min walk distance, but mortality, hospitalization, and thromboembolism rates were not different between the rhythm and rate control groups.

CONCLUSIONS

In AF combined with HF, even though mortality, hospitalization and thromboembolism rates were similar, a rhythm control strategy was superior to rate control in terms of improvement in LVEF, exercise capacity, and QOL. In particular, the CA group was superior to the AAD group for reversal of cardiac remodeling.

Functional improvement after successful catheter ablation for long-standing persistent atrial fibrillation

Aims

Identifying patients who benefit from restored sinus rhythm (SR) would optimize the selection of candidates for ablation of long-standing persistent atrial fibrillation (LSPAF). This prospective study sought to identify the hitherto unknown factors associated with global functional improvement after successful radiofrequency catheter ablation of LSPAF.

Methods and results

In 171 LSPAF patients (84% of the total consecutive 203 patients) who were examined in SR 12 months after ablation, the individual per cent change from baseline value in maximum oxygen consumption at exercise test (VO2 max), left ventricular ejection fraction (LVEF), N-terminal prohormone of brain natriuretic peptide (NT-proBNP), and five-dimensional descriptive system (EQ-5D) of quality-of-life questionnaire were classified in quartiles by 0 (worse) to 3 (best) grades. The individual grades were summed into a composite score (SCORE, 0 … 12) reflecting global functional improvement. Significant improvement in VO2 max (3.4 ± 4.7 mL/kg/min), LVEF (7.5 ± 9.1%), NT-proBNP (-861 ± 809 pg/mL), and EQ-5D (0.7 ± 0.12) was observed (all P < 0.0001). On multivariable analysis, younger age (P = 0.001), male gender (P = 0.02), timely post-ablation left atrial appendage (LAA) outflow (P = 0.005) with improvement in outflow velocity (P = 0.0002), and withdrawal of Class I/III antiarrhythmic drugs (P < 0.05) were positively and independently correlated with the SCORE.

Conclusions

Younger male patients benefited most from catheter ablation of LSPAF. Delayed or non-improved LAA outflow and inability to discontinue Class I/III antiarrhythmic medication reduced the post-ablation functional improvement.

Avoiding non-responders to cardiac resynchronization therapy: a practical guide

Over two decades after the introduction of cardiac resynchronization therapy (CRT) into clinical practice, ∼30% of candidates continue to fail to respond to this highly effective treatment of drug-refractory heart failure (HF). Since the causes of this non-response (NR) are multifactorial, it will require multidisciplinary efforts to overcome. Progress has, thus far, been slowed by several factors, ranging from a lack of consensus regarding the definition of NR and technological limitations to the delivery of therapy. We critically review the various endpoints that have been used in landmark clinical trials of CRT, and the variability in response rates that has been observed as a result of these different investigational designs, different sample populations enrolled and different means of therapy delivered, including new means of multisite and left ventricular endocardial simulation. Precise recommendations are offered regarding the optimal device programming, use of telemonitoring and optimization of management of HF. Potentially reversible causes of NR to CRT are reviewed, with emphasis on loss of biventricular stimulation due to competing arrhythmias. The prevention of NR to CRT is essential to improve the overall performance of this treatment and lower its risk-benefit ratio. These objectives require collaborative efforts by the HF team, the electrophysiologists and the cardiac imaging experts.

Catheter Ablation for Atrial Fibrillation with Heart Failure

BACKGROUND

Mortality and morbidity are higher among patients with atrial fibrillation and heart failure than among those with heart failure alone. Catheter ablation for atrial fibrillation has been proposed as a means of improving outcomes among patients with heart failure who are otherwise receiving appropriate treatment.

METHODS

We randomly assigned patients with symptomatic paroxysmal or persistent atrial fibrillation who did not have a response to antiarrhythmic drugs, had unacceptable side effects, or were unwilling to take these drugs to undergo either catheter ablation (179 patients) or medical therapy (rate or rhythm control) (184 patients) for atrial fibrillation in addition to guidelines-based therapy for heart failure. All the patients had New York Heart Association class II, III, or IV heart failure, a left ventricular ejection fraction of 35% or less, and an implanted defibrillator. The primary end point was a composite of death from any cause or hospitalization for worsening heart failure.

RESULTS

After a median follow-up of 37.8 months, the primary composite end point occurred in significantly fewer patients in the ablation group than in the medical-therapy group (51 patients [28.5%] vs. 82 patients [44.6%]; hazard ratio, 0.62; 95% confidence interval [CI], 0.43 to 0.87; P=0.007). Significantly fewer patients in the ablation group died from any cause (24 [13.4%] vs. 46 [25.0%]; hazard ratio, 0.53; 95% CI, 0.32 to 0.86; P=0.01), were hospitalized for worsening heart failure (37 [20.7%] vs. 66 [35.9%]; hazard ratio, 0.56; 95% CI, 0.37 to 0.83; P=0.004), or died from cardiovascular causes (20 [11.2%] vs. 41 [22.3%]; hazard ratio, 0.49; 95% CI, 0.29 to 0.84; P=0.009).

CONCLUSIONS

Catheter ablation for atrial fibrillation in patients with heart failure was associated with a significantly lower rate of a composite end point of death from any cause or hospitalization for worsening heart failure than was medical therapy. (Funded by Biotronik; CASTLE-AF ClinicalTrials.gov number, NCT00643188 .).

Ablation for Atrial Fibrillation in Heart Failure with Reduced Ejection Fraction

AF and heart failure with reduced ejection fraction (HFrEF) frequently coexist. Catheter ablation is an increasingly utilised treatment strategy for patients with AF and can be safely performed and is effective in achieving sinus rhythm for patients with HFrEF. Successful ablation may result in improved LV function, clinical heart failure status, quality of life and possibly even mortality. This review summarises the literature analysing efficacy, safety and outcomes of AF ablation for patients with HFrEF.

Treatment of Atrial Fibrillation in Patients with Co-existing Heart Failure and Reduced Ejection Fraction: Time to Revisit the Management Guidelines?

AF in patients with heart failure and reduced ejection fraction (HFrEF) is common and is associated with an increased risk of stroke, heart failure hospitalisation and all-cause mortality. Rhythm control of AF in this population has been traditionally limited to the use of antiarrhythmic drugs. Clinical trials assessing superiority of pharmacological rhythm control over rate control have been largely disappointing. Catheter ablation has emerged as a viable alternative to pharmacological rhythm control in symptomatic AF and has enjoyed significant technological advancements over the past decade. Recent clinical trials have suggested that catheter ablation is superior to pharmacological interventions in patients with co-existing AF and HFrEF. In this article, we will review the therapeutic options for AF in patients with HFrEF in the context of the latest clinical trials beyond the current established guidelines.

Catheter ablation of atrial fibrillation in patients with heart failure and preserved ejection fraction

BACKGROUND

Few studies have examined outcomes of catheter ablation for atrial fibrillation (AF) in patients with heart failure (HF) with preserved ejection fraction (HFpEF).

OBJECTIVE

The purpose of this study was to compare outcomes of AF ablation in patients with HFpEF vs HF with reduced ejection fraction (HFrEF).

METHODS

We performed a retrospective study of 230 patients with HF who underwent AF ablation, including 97 (42.2%) with HFrEF and 133 (57.8%) with HFpEF. Outcomes included adverse events, symptoms (Mayo AF Symptom Inventory [MAFSI]), New York Heart Association (NYHA) functional class, and freedom from recurrent atrial arrhythmia at 12 months.

RESULTS

Overall, 150 of 230 patients had nonparoxysmal AF (62.8% HFpEF vs 63.0% HFrEF). Patients with HFpEF had a smaller mean left atrial diameter (4.4 ± 0.8 cm vs 4.7 ± 0.7 cm; P = .013) and were less likely to be taking a beta-blocker at baseline (72.9% vs 85.6%; P = .022). Median (Q1, Q3) procedure times (233 minutes [192, 290] vs 233.5 minutes [193.0, 297.5]; P = .780) and adverse events such as acute HF (3.8% vs 6.2%; P = .395) were similar between HFpEF and HFrEF patients. Freedom from recurrent atrial arrhythmia was not significantly different in HFpEF vs HFrEF patients (33.9% vs 32.6%; adjusted hazard ratio 1.47; 95% confidence interval 0.72-3.01), with similar improvements in NYHA functional class (-0.32 vs -0.19; P = .135) and MAFSI symptom severity (-0.23 vs -0.09; P = .116) after ablation.

CONCLUSION

Catheter ablation of AF seems to have similar effectiveness in patients with HF, regardless of presence of systolic dysfunction. There were no significant differences in procedural characteristics, arrhythmia-free recurrence, or functional improvements between patients with HFpEF and those with HFrEF.

Catheter ablation versus rate control in patients with atrial fibrillation and heart failure: A multicenter study

Many trials have shown improvements in left ventricular function, exercise capacity, and quality of life after catheter ablation (CA) of atrial fibrillation (AF) in patients with heart failure (HF). We sought to evaluate the impact of CA on hard outcomes in a retrospective cohort study. AF patients with symptomatic HF from 3 hospitals were included. Our primary endpoint was major adverse cardiac events (MACEs), a composite of all-cause mortality, stroke, and unplanned hospitalization. In total, 90 patients underwent CA and 304 ones received rate control (RaC) were included. After a mean follow-up of 13.5 ± 5.3 months, 82.2% of patients in CA group got freedom from AF; all patients in RaC group remained in AF. CA group had a significant decreased risk of MACEs compared with RaC group (13.3% vs 29.3%, hazard ratio [HR] 0.51, 95% confidence interval [CI]: 0.32-0.82, P = .005). After propensity score matched for confounding factors, difference in MACEs remained significant between groups (13.3% vs 25.6%, HR 0.50, 95% CI: 0.26-0.98, P = .044). Multivariate regression analysis also indicated that CA was significantly associated with a lower risk of MACEs in overall cohort (HR 0.486, 95% CI: 0.253-0.933, P = .030) and in propensity-matched cohort (HR 0.482, 95% CI: 0.235-0.985, P = .045). Besides, age and NYHA class were associated with an increased risk of MACEs. In conclusion, the present study demonstrated that CA for AF in HF patients could reduce the risk of MACEs in a mid-term follow-up. Thus, CA may be a reasonable option for this population.

The effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter: A systematic review with meta-analysis and Trial Sequential Analysis

Background

Atrial fibrillation and atrial flutter may be managed by either a rhythm control strategy or a rate control strategy but the evidence on the clinical effects of these two intervention strategies is unclear. Our objective was to assess the beneficial and harmful effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter.

Methods

We searched CENTRAL, MEDLINE, Embase, LILACS, Web of Science, BIOSIS, Google Scholar, clinicaltrials.gov, TRIP, EU-CTR, Chi-CTR, and ICTRP for eligible trials comparing any rhythm control strategy with any rate control strategy in patients with atrial fibrillation or atrial flutter published before November 2016. Our primary outcomes were all-cause mortality, serious adverse events, and quality of life. Our secondary outcomes were stroke and ejection fraction. We performed both random-effects and fixed-effect meta-analysis and chose the most conservative result as our primary result. We used Trial Sequential Analysis (TSA) to control for random errors. Statistical heterogeneity was assessed by visual inspection of forest plots and by calculating inconsistency (I²) for traditional meta-analyses and diversity (D²) for TSA. Sensitivity analyses and subgroup analyses were conducted to explore the reasons for substantial statistical heterogeneity. We assessed the risk of publication bias in meta-analyses consisting of 10 trials or more with tests for funnel plot asymmetry. We used GRADE to assess the quality of the body of evidence.

Results

25 randomized clinical trials (n = 9354 participants) were included, all of which were at high risk of bias. Meta-analysis showed that rhythm control strategies versus rate control strategies significantly increased the risk of a serious adverse event (risk ratio (RR), 1.10; 95% confidence interval (CI), 1.02 to 1.18; P = 0.02; I² = 12% (95% CI 0.00 to 0.32); 21 trials), but TSA did not confirm this result (TSA-adjusted CI 0.99 to 1.22). The increased risk of a serious adverse event did not seem to be caused by any single component of the composite outcome. Meta-analysis showed that rhythm control strategies versus rate control strategies were associated with better SF-36 physical component score (mean difference (MD), 6.93 points; 95% CI, 2.25 to 11.61; P = 0.004; I² = 95% (95% CI 0.94 to 0.96); 8 trials) and ejection fraction (MD, 4.20%; 95% CI, 0.54 to 7.87; P = 0.02; I² = 79% (95% CI 0.69 to 0.85); 7 trials), but TSA did not confirm these results. Both meta-analysis and TSA showed no significant differences on all-cause mortality, SF-36 mental component score, Minnesota Living with Heart Failure Questionnaire, and stroke.

Conclusions

Rhythm control strategies compared with rate control strategies seem to significantly increase the risk of a serious adverse event in patients with atrial fibrillation. Based on current evidence, it seems that most patients with atrial fibrillation should be treated with a rate control strategy unless there are specific reasons (e.g., patients with unbearable symptoms due to atrial fibrillation or patients who are hemodynamically unstable due to atrial fibrillation) justifying a rhythm control strategy. More randomized trials at low risk of bias and low risk of random errors are needed.

Trial registration

PROSPERO CRD42016051433

Recent advances in rhythm control for atrial fibrillation

Atrial fibrillation (AF) remains a difficult management problem. The restoration and maintenance of sinus rhythm-rhythm control therapy-can markedly improve symptoms and haemodynamics for patients who have paroxysmal or persistent AF, but some patients fare well with rate control alone. Sinus rhythm can be achieved with anti-arrhythmic drugs or electrical cardioversion, but the maintenance of sinus rhythm without recurrence is more challenging. Catheter ablation of the AF triggers is more effective than anti-arrhythmic drugs at maintaining sinus rhythm. Whilst pulmonary vein isolation is an effective strategy, other ablation targets are being evaluated to improve sinus rhythm maintenance, especially in patients with chronic forms of AF. Previously extensive ablation strategies have been used for patients with persistent AF, but a recent trial has shown that pulmonary vein isolation without additional ablation lesions is associated with outcomes similar to those of more extensive ablation. This has led to an increase in catheter-based technology to achieve durable pulmonary vein isolation. Furthermore, a combination of anti-arrhythmic drugs and catheter ablation seems useful to improve the effectiveness of rhythm control therapy. Two large ongoing trials evaluate whether a modern rhythm control therapy can improve prognosis in patients with AF.

Atrial Fibrillation in Heart Failure: a Therapeutic Challenge of Our Times

Atrial fibrillation (AF) and heart failure (HF) are growing cardiovascular disease epidemics worldwide. There has been an exponential increase in the prevalence of AF and HF correlating with an increased burden of cardiac risk factors and improved survival rates in patients with structural heart disease. AF is associated with adverse prognostic outcomes in HF and is most evident in mild-to-moderate left ventricular (LV) dysfunction where the loss of "atrial kick" translates into poorer quality of life and increased mortality. In the absence of underlying structural heart disease, arrhythmia can independently contribute to the development of cardiomyopathy. Together, these 2 conditions carry a high risk of thromboembolism due to stasis, inflammation and cellular dysfunction. Stroke prevention with oral anticoagulation (OAC) remains a mainstay of treatment. Pharmacologic rate and rhythm control remain limited by variable efficacy, intolerance and adverse reactions. Catheter ablation for AF has resulted in a paradigm shift with evidence indicating superiority over medical therapy. While its therapeutic success is high for paroxysmal AF, it remains suboptimal in persistent AF. A better mechanistic understanding of AF as well as innovations in ablation technology may improve patient outcomes in the future. Refractory cases may benefit from atrioventricular junction ablation and biventricular pacing. The value of risk factor modification, especially with regard to obesity, sleep apnea, hypertension and diabetes, cannot be emphasized enough. Close interdisciplinary collaboration between HF specialists and electrophysiologists is an essential component of good long-term outcomes in this challenging population.

Conduction recovery following catheter ablation in patients with recurrent atrial fibrillation and heart failure

BACKGROUND

Atrial fibrillation (AF) catheter ablation is increasingly proposed for patients suffering from AF and concomitant heart failure (HF). However, the optimal ablation strategy remains controversial. We performed this study to assess the prevalence of pulmonary vein (PV) or linear lesion reconnection in HF patients undergoing repeated procedures.

METHODS AND RESULTS

At seven high-volume centres, 165 patients with HF underwent a repeat procedure after a first AF ablation including PV isolation alone (47 patients, group A) or PV isolation plus left atrial lines (118 patients, group B). Group A patients presented more often paroxysmal AF (p<0.001), less enlarged left atrium (p<0.001) and less left ventricular systolic dysfunction (p=0.031) compared to Group B, that more commonly had atypical atrial flutter (p<0.001). Forty-one (87%) patients in Group A and 69 (58%) in Group B presented at least one reconnected PV (p<0.001). Sixty-one (52%) patients in Group B presented at least one reconnected atrial line (left isthmus or roof). Patients without any reconnected PV (n=54, 33%) more frequently experienced persistent AF (p<0.001), had longer AF duration (p=0.047) and larger left atrial volume (p<0.001). Twenty-five patients (15%) with no PV and/or line reconnection did not significantly differ, concerning baseline characteristics, compared to those with at least one reconnected ablation site.

CONCLUSION

As in the general AF population undergoing catheter ablation, PV reconnection is frequent in patients with HF and symptomatic recurrence. However, one third of patients presented arrhythmic recurrences even in the absence of PV reconnection, highlighting the importance of the underlying atrial substrate.

Persistent atrial fibrillation vs paroxysmal atrial fibrillation: differences in management

INTRODUCTION

Atrial fibrillation (AF) is the most common human arrhythmia. AF is a progressive disease, initially being nonsustained and induced by trigger activity, and progressing towards persistent AF through alteration of the atrial myocardial substrate. Treatment of AF aims to decrease the risk of stroke and improve the quality of life, by preventing recurrences (rhythm control) or controlling the heart rate during AF (rate control). In the last 20 years, catheter-based and, less frequently, surgical and hybrid ablation techniques have proven more successful compared with drug therapy in achieving rhythm control in patients with AF. However, the efficiency of ablation techniques varies greatly, being highest in paroxysmal and lowest in long-term persistent AF. Areas covered: In this review, we discuss the fundamental differences between paroxysmal and persistent AF and the potential impact of those differences on patient management, emphasizing the available therapeutic strategies to achieve rhythm control. Expert commentary: Treatment to prevent AF recurrences is suboptimal, particularly in patients with persistent AF. Emerging technologies, such as documentation of atrial fibrosis using magnetic resonance imaging and documentation of electrical substrate using advanced electrocardiographic imaging techniques are likely to provide valuable insights about patient-specific tailoring of treatments.

EFFICIENCY AND SAFETY OF RADIOFREQUENCY CATHETER ABLATION OF ATRIAL FIBRILLATION IN ELDERLY PATIENTS

Atrial fibrillation is one of the most frequent and significant rhythm disturbances. The effectiveness and expediency of using one of the most effective methods of treatment of this arrhythmia (radiofrequency ablation in elderly patients) remains a controversial and insufficiently studied issue. The article compares the results of the treatment of 63 patients of mature age (up to 75 years) and senile age (from 75 years). Patients underwent 78 operations of radiofrequency catheter ablation of atrial fibrillation and atypical atrial flutter, which was resistant to drug therapy. In the groups of patients of mature and senile age, there were no statistically significant differences in the effectiveness of treatment. In elderly people group, a higher incidence of complications was found mainly due to hydrothorax, but these complications did not increase the risk of death and were stopped during treatment. This allows to conclude that the senile age of patients should not be the reason for refusing to conduct radiofrequency catheter ablation.

Atrial Fibrillation and Heart Failure - Cause or Effect?

There are emerging epidemics of atrial fibrillation (AF) and heart failure in most developed countries, with a significant health burden. Due to many shared pathophysiological mechanisms, which facilitate the maintenance of each condition, AF and heart failure co-exist in up to 30% of patients. In the circumstance where known structural causes of heart failure (such as myocardial infarction) are absent, patients presenting with both conditions present a unique challenge, particularly as the temporal relationship of each condition can often remain elusive from the clinical history. The question of whether the AF is driving, or significantly contributing to the left ventricular (LV) dysfunction, rather than merely a consequence of heart failure, has become ever more pertinent, especially as catheter ablation now offers a significant advancement over existing rhythm control strategies. This paper will review the inter-related physiological drivers of AF and heart failure before considering the implications from the outcomes of recent clinical trials in patients with AF and heart failure.

Catheter Ablation for Persistent and Long-Standing Persistent Atrial Fibrillation

Persistent and long-standing persistent atrial fibrillation evolves from complex arrhythmogenic substrate and sources. Multiple studies have shown improved freedom from arrhythmia recurrences if sinus rhythm had been restored during the index ablation; however, such harder procedural endpoint requires laborious stepwise approach almost invariably pursuing non-pulmonary-vein sources. Longer-term conversion of persistent atrial fibrillation into sinus rhythm is associated with significant improvement in major indices of hemodynamic and functional status; these indices also represent major predictors of cardiovascular mortality. Optimal ablation techniques and strategies preserving most of the individual potential for functional improvement need to be established.

The burden of proof: The current state of atrial fibrillation prevention and treatment trials

Atrial fibrillation (AF) is an age-related arrhythmia of enormous socioeconomic significance. In recent years, our understanding of the basic mechanisms that initiate and perpetuate AF has evolved rapidly, catheter ablation of AF has progressed from concept to reality, and recent studies suggest lifestyle modification may help prevent AF recurrence. Emerging developments in genetics, imaging, and informatics also present new opportunities for personalized care. However, considerable challenges remain. These include a paucity of studies examining AF prevention, modest efficacy of existing antiarrhythmic therapies, diverse ablation technologies and practice, and limited evidence to guide management of high-risk patients with multiple comorbidities. Studies examining the long-term effects of AF catheter ablation on morbidity and mortality outcomes are not yet completed. In many ways, further progress in the field is heavily contingent on the feasibility, capacity, and efficiency of clinical trials to incorporate the rapidly evolving knowledge base and to provide substantive evidence for novel AF therapeutic strategies. This review outlines the current state of AF prevention and treatment trials, including the foreseeable challenges, as discussed by a unique forum of clinical trialists, scientists, and regulatory representatives in a session endorsed by the Heart Rhythm Society at the 12th Global CardioVascular Clinical Trialists Forum in Washington, DC, December 3-5, 2015.

Treatment of Patients With Atrial Fibrillation and Heart Failure With Reduced Ejection Fraction

Atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF) frequently coexist, and each complicates the course and treatment of the other. Recent population-based studies have demonstrated that the 2 conditions together increase the risk of stroke, heart failure hospitalization, and all-cause mortality, especially soon after the clinical onset of AF. Guideline-directed pharmacological therapy for HFrEF is important; however, although there are various treatment modalities for AF, there is no clear consensus on how best to treat AF with concomitant HFrEF. This in-depth review discusses the available data for the treatment of AF in the setting of HFrEF, focuses on areas where more investigation is necessary, examines the clinical implications of randomized and observational clinical trials, and presents suggestions for individualized treatment strategies for specific patient groups.

Perioperative Outcomes and Safety of Atrial Fibrillation Catheter Ablation in Octogenarians: A Retrospective Study and Review of the Benefits of Rhythm Control

OBJECTIVES

Catheter ablation for rhythm control has emerged as a successful therapeutic option for the treatment of atrial fibrillation (AF), though it has not been well studied in octogenarians. This study evaluates its safety in octogenarians in a community hospital and reviews the benefits of rhythm control.

METHODS

Among 1,592 patients undergoing AF ablation, 84 octogenarian were identified. The primary outcome was normal sinus rhythm (NSR) on electrocardiogram at discharge. Secondary outcomes were periprocedural complications and markers and risks of reablation compared to younger cohorts.

RESULTS

An NSR on discharge occurred in 83 patients. Three patients required pacing for symptomatic sinus bradycardia, complete heart block, and symptomatic junctional bradycardia, respectively. Reablation for recurrent AF occurred in 23 octogenarians. Using the octogenarians as reference, the relative risk (RR) of 1 reablation was not significantly different among the age groups 70-79, 60-69, and <60 years. The RR of 2 reablations was greater in the octogenarian group (RR 0.26 [95% CI 0.09-0.71, p = 0.008], 0.42 [95% CI 0.17-1.04, p = 0.06], and 0.27 [95% CI 0.1-0.75, p = 0.01], respectively). Coronary artery disease (OR 0.14, 95% CI 0.02-0.68, p = 0.026) and percutaneous coronary intervention (OR 0.13, 95% CI 0.02-0.63, p = 0.021) were markers for reablation.

CONCLUSION

AF catheter ablation achieved an NSR with minimal periprocedural complications. The benefits of rhythm control should be considered in treatment.

Efficacy and effects on cardiac function of radiofrequency catheter ablation vs. direct current cardioversion of persistent atrial fibrillation with left ventricular systolic dysfunction

OBJECTIVE

To evaluate the effect of catheter ablation vs. direct current synchronized cardioversion (DCC) in patients with persistent atrial fibrillation (AF) and left ventricular systolic dysfunction, and to define baseline features of patients that will get more benefit from ablation.

METHODS

From July 2013 to October 2014, 97 consecutive single-center patients with persistent AF and symptomatic heart failure (left ventricular ejection fraction (LVEF) <50%) underwent DCC followed by amiodarone (n = 40) or circumferential pulmonary vein isolation (PVI; n = 57) according to patient's preference were recruited in the study. Post-ablation recurrence was treated with atrial roof and mitral isthmus lines ablation with or without PVI based on restoration or not of pulmonary vein (PV) potential conduction. Study outcomes were 12-month rate of sustained sinus rhythm (SR) and cardiac function. Baseline characteristics were compared between patients with and without cardiac function improvement post ablation.

RESULTS

With similarly distributed characteristics at baseline, ablation (mean 1.8 procedures) relative to DCC yielded significantly higher level of 12-month SR maintenance rate (68.42% vs. 35%, P = 0.001); and better LVEF and New York Heart Association class. with significant effect for DCC only in maintained SR cases. Post ablation LVEF increased (>20% or to over 55%) in 31 (54.39%) patients with worse baseline cardiac function and ventricular rate control.

CONCLUSIONS

Catheter ablation relative to cardioversion of persistent AF with symptomatic heart failure yielded better 12-month SR maintenance and cardiac function. Compared with non-responders, patients with improved LVEF post-ablation had poorer ventricular rate control and cardiac function at baseline, suggesting a significant component of tachycardia-induced cardiomyopathy in this group.

Rosuvastatin reduces the recurrence rate following catheter ablation for atrial fibrillation in patients with heart failure

The aim of the present study was to assess whether rosuvastatin could reduce the recurrence rate of atrial fibrillation (AF) in patients with heart failure (HF) following catheter ablation (CA). A total of 107 patients with HF and AF who underwent CA of AF by endocardial mapping and radiofrequency between June 2012 and May 2014 were recruited. The patients were randomly divided into three subgroups: i) Administered with 10 mg rosuvastatin daily following ablation (group 1, n=36); ii) administered with 20 mg rosuvastatin daily following ablation (group 2, n=36); and iii) only treated with conventional treatment of HF following ablation (group 3, n=35). After the procedure, patients were followed in the outpatient clinic by interrogation of Holter monitoring. The AF recurrence rate of group 2 was low in comparison with group 1 (22.2% vs. 38.9%, P=0.013) and group 3 (22.2% vs. 48.6%, P=0.021). In comparison with baseline, the parameters of the left ventricular ejection fraction, left atrial diameter (LAD), and the levels of N-terminal pronatriuretic peptide and hypersensitive C-reactive protein (hs-CRP) were all improved in three groups. Furthermore, multivariate analysis demonstrated that LAD [hazard ratio (HR): 1.12, 95% confidence interval (CI): 1.06-1.67, P=0.049], hs-CRP (HR: 1.37, 95% CI: 1.11-1.92, P=0.002) and duration of AF (HR: 1.14, 95% CI: 1.09-1.18, P=0.011) were independent predictors of AF recurrence in patients with HF following CA. Therefore, the present study has demonstrated that treatment with 20 mg rosuvastatin daily following CA was able to significantly decrease the recurrence rate of AF in patients with HF, and LAD, hs-CRP, and duration of AF were independent predictors of AF recurrence in patients with HF following CA. In conclusion, the present study has also demonstrated that CA may improve cardiac function in patients with HF and AF.

How to Improve Cardiac Resynchronization Therapy Benefit in Atrial Fibrillation Patients: Pulmonary Vein Isolation (and Beyond)

Although cardiac resynchronization therapy (CRT) is an important treatment of symptomatic heart failure patients in sinus rhythm with low left ventricular ejection fraction and ventricular dyssynchrony, its role is not well defined in patients with atrial fibrillation (AF). CRT is not as effective in patients with AF because of inadequate biventricular capture and loss of atrioventricular synchrony. Both can be addressed with catheter ablation of AF. It is still unclear if these therapies offer additive benefits in patients with ventricular dyssynchrony. This article discusses the role and techniques of catheter ablation of AF in patients with heart failure, and its application in CRT recipients.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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