Atrial fibrillation ablation in heart failure: What do we know? What can we do?

Atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF) are two conditions that frequently impact reciprocally on each other. Patients with HFrEF have an increased risk of stroke, hospitalization and mortality after they develop AF and vice versa, AF causing deterioration of the ejection fraction is also associated to increased mortality. Catheter ablation has emerged as an effective alternative to antiarrhythmic drug treatment to maintain sinus rhythm and some randomized trials have shown a potential benefit in terms of mortality and hospitalization. This review discusses the available evidence regarding catheter ablation treatment in this specific patient group.

Combination of ablation and left atrial appendage closure as "One-stop" procedure in the treatment of atrial fibrillation: Current status and future perspective

Atrial fibrillation (AF), the most common arrhythmia, is a major cause of stroke and systemic embolism. Left atrial appendage closure (LAAC) has been proved to be noninferior to traditional Vitamin K antagonists (VKAs) as well as novel oral anticoagulants (NOACs), which is becoming an important alternative to prevent stroke in non‐valvular AF. Catheter‐based AF ablation (CA) is recommended to be a standard of care in patients with AF refractory to drug therapy due to a better rhythm control and improvement of life quality than antiarrhythmic drugs. Theoretically, the one‐stop combination with LAAC and CA tends to bring more benefits in patients with AF, as it not only relieves symptoms, but also reduces the risk of stroke significantly. However, several important questions still need to be considered in the combination procedure although quite a few attempts have already been made in clinical practice. This review provides a comprehensive update on the concept, technique, perioperative management, benefits and other critical issues of the “one‐stop” procedure.

Echocardiographic assessment in patients with atrial fibrillation (AF) and normal systolic left ventricular function before and after catheter ablation: If AF begets AF, does pulmonary vein isolation terminate the vicious circle?

BACKGROUND

Radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) can be curative. There are conflicting data on whether AF associated atrial and ventricular structural remodeling reverses after ablation. The aim of this study was to evaluate the hemodynamic effect of AF ablation in patients with preserved left ventricular ejection fraction (LVEF).

METHODS

Forty three AF patients were studied (aged 56 ± 11 years; 29 male, 23% persistent AF, LVEF ≥ 50%) in whom RFCA was performed. Echocardiographic evaluation of atrial and ventricular diameters, volumes and strain imaging by two-dimensional speckle tracking were performed before and at least 6 months after RFCA. Nine patients had AF during baseline examination.

RESULTS

A significant decrease in the left (LA) and right (RA) atrial volume and an increase in the LA strain were observed 15 ± 7 months after RFCA. In the subgroup with baseline sinus rhythm, the increment in LA strain was only borderline significant. An increase in RA, right ventricular (RV) and Biatrial strain was noticed (p < 0.05). LVEF and global longitudinal strain of the left ventricle (LV), however, did not improve substantially.

CONCLUSIONS

Radiofrequency catheter ablation of AF in patients with preserved LV systolic function results in significant improvement in RA and RV function with a substantial reduction in LA and RA size. No deleterious impact of AF ablation on LA function was revealed.

Catheter Ablation of Atrial Fibrillation in Patients With Heart Failure

Atrial fibrillation (AF) and heart failure (HF) both have become major cardiovascular epidemics, adversely affecting quality of life, decreasing longevity, and imparting a large economic burden on the healthcare system. Both share similar risk factors and frequently coexist, leading to increased morbidity and mortality relative to patients with either condition alone. Although evidence-based treatment guidelines for both diseases exist, consensus treatment strategies are less clear when AF and HF co-occur. Given the risks of antiarrhythmic drugs and their incomplete success in maintaining sinus rhythm, catheter ablation has become an increasingly popular alternative to pharmacologic rhythm control in symptomatic patients with AF with normal cardiac function. Although multiple studies have demonstrated the efficacy of catheter ablation in AF, studies examining the use of catheter ablation specifically in patients with HF have recently begun to emerge and provide some guidance in this group of patients. In this review, we examine the effects of catheter ablation of AF in patients with HF on maintenance of sinus rhythm, left ventricular ejection fraction, exercise capacity, quality of life, hospitalization, and mortality rates. Data regarding both HF with reduced ejection fraction and preserved ejection fraction are discussed.

Catheter Ablation for Atrial Fibrillation in Systolic Heart Failure Patients: Stone by Stone, a CASTLE

Heart failure (HF) and AF frequently coexist and are involved in a vicious cycle of adverse pathophysiologic interactions. Applying treatment algorithms that have been validated in the general AF population to patients with AF and HF may be fraught with risks and lack effectiveness. While firm recommendations on using catheter ablation for AF do exist, the subset of patients also suffering from HF needs to be further evaluated. Observational data indicate that a significant number of ablation procedures are performed in patients with coexistent HF. Initial randomised data on outcomes are encouraging. Apart from sinus rhythm maintenance, benefits have been observed in terms of other significant endpoints, including left ventricular ejection fraction, quality of life, exercise capacity and hospital readmissions for HF. Limited existing data on survival are also promising. In the present article, observational and randomised studies along with current practice guidelines are summarised.

Improvement of Hemodynamic Parameters in Patients With Preserved Left Ventricular Systolic Function by Catheter Ablation of Atrial Fibrillation - A Prospective Study Using Impedance Cardiography

BACKGROUND

The effects of catheter ablation for atrial fibrillation (AF) on hemodynamic parameters in patients with preserved left ventricular (LV) systolic function are unclear. Methods and Results: We enrolled 178 patients with AF (paroxysmal, 108; persistent, 70) with preserved LV systolic function who underwent AF ablation. The stroke volume index (SVI) was repeatedly measured using impedance cardiography. Reduced SVI (SVI, <33 mL/m²) was observed in 55% of patients before ablation. In patients with paroxysmal AF, the SVI did not change immediately after ablation (from 35±6 mL/m²to 35±5 mL/m²; P=0.652); however, it increased 1 month after ablation and further increased 6 months after ablation (1 month, 37±6 mL/m², P<0.001; 6 months, 38±6 mL/m², P<0.001). In patients with persistent AF, the SVI increased immediately after ablation (from 30±5 mL/m²to 36±6 mL/m²; P<0.001) and further increased until 6 months after ablation (1 month, 37±6 mL, P<0.001; 6 months, 38±5 mL/m², P<0.001). The baseline SVI was the strongest predictor of the cardiac function improvement with an area under the curve of 0.828.

CONCLUSIONS

The restoration and maintenance of sinus rhythm using catheter ablation increased the SVI in patients with preserved LV systolic function.

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.

Predictors of arrhythmia recurrence in patients with heart failure undergoing left atrial ablation for atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) ablation is increasingly used in patients with reduced left ventricular ejection fraction (LVEF). The aim of the present study was to evaluate the long-term results of a single radiofrequency catheter ablation procedure in heart failure (HF) patients with AF.

HYPOTHESIS

We tested the hypothesis that left atrial ablation is an effective therapeutic modality in patients with heart failure.

METHODS

Our study included HF patients with LVEF <50% who underwent catheter ablation for AF at our department between January 2010 and March 2017. All patients underwent our institution's protocol for follow-up post-ablation.

RESULTS

The study enrolled a total of 38 patients (mean age, 54.1 ± 12.2 years; 28 [73.7%] males; mean LVEF, 38.2% ± 6.3%). After a mean follow-up period of 38.2 months (range, 5-92 months), 28 patients (73.7%) were free from arrhythmia recurrence. In multivariate analysis, early arrhythmia recurrence (P = 0.03) and amiodarone antiarrhythmic drug administration (P = 0.003) remained independent predictors of arrhythmia recurrence.

CONCLUSIONS

The main findings of this study are that (1) a single radiofrequency catheter ablation procedure is an effective and safe modality for AF in patients with concomitant HF; (2) after a mean 3.3 years of follow-up, 73.7% of HF patients remained in sinus rhythm; and (3) early arrhythmia recurrence was a significant predictor of arrhythmia recurrence after the blanking period.

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.

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.

Catheter ablation versus medical rate control for persistent atrial fibrillation in patients with heart failure: A PRISMA-compliant systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The effectiveness of restoring the sinus rhythm by catheter ablation relative to that of medical rate control for persistent atrial fibrillation (AF) patients with heart failure (HF) remains to be defined.

METHODS

We systematically searched Embase, Pubmed, the Cochrane Library, and ClinicalTrials.gov for articles that compared the outcomes of interest between catheter ablation and medical rate control therapy in persistent AF patients with HF and left ventricular systolic dysfunction (LVSD). The primary endpoint was the change in the left ventricular ejection fraction (LVEF) following catheter ablation or medical rate control therapy relative to baseline. Other endpoints included changes in cardiac function and exercise capacity, including the New York Heart Association (NYHA) class, the brain natriuretic peptide (BNP) level, the peak oxygen consumption (peak VO2), the 6-minute walk test (6MWT) results, and quality of life (QOL).

RESULTS

Three randomized controlled trials (RCTs) with 143 patients were included. At the overall term follow-up, catheter ablation significantly improved the LVEF (mean difference [MD]: 6.22%; 95% confidence interval [CI]: 0.7-11.74, P = 0.03) and peak VO2 (MD: 2.81 mL/kg/min; 95% CI: 0.78-4.85, P = 0.007) and reduced the NYHA class (MD: 0.9; 95% CI: 0.59-1.21, P < 0.001) and the Minnesota Living with Heart Failure Questionnaires (MLHFQ) scores (MD: -11.05; 95% CI: -19.45 - -2.66, P = 0.01) compared with the medical rate control for persistent AF patients with HF. Alterations in parameters, such as the BNP level, 6MWT, and Short Form-36 (SF-36) questionnaire scores also revealed trends that favored catheter ablation therapy, although these differences were not significant.

CONCLUSION

Catheter ablation resulted in improved LVEF, cardiac function, exercise capacity, and QOL for persistent AF patients with HF compared with the medical rate control strategy.

Impact of Additional Transthoracic Electrical Cardioversion on Cardiac Function and Atrial Fibrillation Recurrence in Patients with Persistent Atrial Fibrillation Who Underwent Radiofrequency Catheter Ablation

Backgrounds and Objective. During the procession of radiofrequency catheter ablation (RFCA) in persistent atrial fibrillation (AF), transthoracic electrical cardioversion (ECV) is required to terminate AF. The purpose of this study was to determine the impact of additional ECV on cardiac function and recurrence of AF. Methods and Results. Persistent AF patients received extensive encircling pulmonary vein isolation (PVI) and additional line ablation. Patients were divided into two groups based on whether they need transthoracic electrical cardioversion to terminate AF: electrical cardioversion (ECV group) and nonelectrical cardioversion (NECV group). Among 111 subjects, 35 patients were returned to sinus rhythm after ablation by ECV (ECV group) and 76 patients had AF termination after the ablation processions (NECV group). During the 12-month follow-ups, the recurrence ratio of patients was comparable in ECV group (15/35) and NECV group (34/76) (44.14% versus 44.74%, P = 0.853). Although left atrial diameters (LAD) decreased significantly in both groups, there were no significant differences in LAD and left ventricular cardiac function between ECV group and NECV group. Conclusions. This study revealed that ECV has no significant impact on the maintenance of SR and the recovery of cardiac function. Therefore, ECV could be applied safely to recover SR during the procedure of catheter ablation of persistent atrial fibrillation.

Ablation as First-Line Therapy for Atrial Fibrillation: Yes

This article addresses the use of catheter ablation (CA) as first-line therapy for atrial fibrillation (AF). CA increases long-term freedom from AF, reduces hospitalizations, and improves quality of life compared with antiarrhythmic drug (AAD) therapy in patients with symptomatic AF who have already failed one AAD. The role of CA as first-line therapy for AF, however, is still controversial. Evidence from randomized controlled trials shows that CA is definitely superior to AADs as first-line therapy for relatively young patients with paroxysmal AF, with comparable complication rates and results consistently reproducible across different institutions, operators, and types of ablation approaches.

Novel perspectives on arrhythmia-induced cardiomyopathy: pathophysiology, clinical manifestations and an update on invasive management strategies

Arrhythmia-induced cardiomyopathy is a partially or completely reversible form of myocardial dysfunction due to sustained supraventricular and ventricular arrhythmias. Asynchrony, rapid cardiac rates and rhythm irregularities are the main factors involved in the development of the disease. The reversible nature of arrhythmia-induced cardiac dysfunction allows only for a retrospective diagnosis of the disease once cardiac function is restored following heart rate control. A high level of suspicion is needed to make a diagnosis at an early stage and prevent further progression of the disease. Although reversible, arrhythmia-induced cellular and molecular changes may remain, increasing the risk for sudden death even when normal ejection fraction is restored as well as causing rapid deterioration of cardiac function and development of heart failure symptoms if arrhythmia recurs. Appropriate management based on a combination of pharmacologic and nonpharmacologic strategies to achieve rate control and prevent arrhythmia recurrence is pivotal to avoid further cardiac function deterioration and to control symptoms, significantly reducing the risk of heart failure and sudden cardiac death.

Atrial fibrillation ablation and left appendage closure in heart failure patients

PURPOSE OF REVIEW

Patients with atrial fibrillation and heart failure experience an increased morbidity and mortality from the hemodynamic consequences of atrial fibrillation and an increased stroke risk. Consequently, there has been increased attention to procedural alternatives to pharmacologic rhythm control and anticoagulation for stroke prevention. This review aims to evaluate the evidence for atrial fibrillation ablation and left atrial appendage closure in heart failure patients.

RECENT FINDINGS

Several randomized control trials and systematic reviews demonstrate the safety and efficacy of atrial fibrillation ablation in patients with heart failure and left ventricular systolic dysfunction. In multiple trials, these patients have shown clinical benefit from atrial fibrillation ablation including improved left ventricular systolic function, quality of life, and clinical heart failure symptoms. The evidence of clinical benefit of atrial fibrillation ablation in heart failure patients with preserved ejection fraction remains limited. Only a handful of randomized controlled trials have been performed evaluating left atrial appendage closure, and there is insufficient data regarding the safety and efficacy of these procedures in heart failure patients.

SUMMARY

Atrial fibrillation ablation in heart failure patients remains well tolerated with an overall efficacy comparable to atrial fibrillation ablation in patients without heart failure. There is consistent evidence for the clinical benefit of atrial fibrillation ablation in heart failure patients with left ventricular systolic dysfunction and limited evidence for atrial fibrillation ablation in heart failure patients with preserved ejection fraction. Currently, there is insufficient data regarding the safety and efficacy of left atrial appendage closure devices in heart failure patients.

Comorbidity of atrial fibrillation and heart failure

Atrial fibrillation (AF) and heart failure (HF) are evolving epidemics, together responsible for substantial human suffering and health-care expenditure. Ageing, improved cardiovascular survival, and epidemiological transition form the basis for their increasing global prevalence. Although we now have a clear picture of how HF promotes AF, gaps remain in our knowledge of how AF exacerbates or even causes HF, and how the development of HF affects the outcome of patients with AF. New data regarding HF with preserved ejection fraction and its unique relationship with AF suggest a possible role for AF in its aetiology, possibly as a trigger for ventricular fibrosis. Deciding on optimal treatment strategies for patients with both AF and HF is increasingly difficult, given that results from trials of pharmacological rhythm control are arguably obsolete in the age of catheter ablation. Restoring sinus rhythm by catheter ablation seems successful in the medium term and improves HF symptoms, functional capacity, and left ventricular function. Long-term studies to examine the effect on rates of stroke and death are ongoing. Guidelines continue to evolve to keep pace with this rapidly changing field.

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.

Atrial fibrillation in heart failure: catheter and surgical interventional therapies

Atrial fibrillation and heart failure commonly coexist in the same patient. Each may adversely affect the other. Atrial fibrillation leads to heart failure exacerbation, left ventricular function deterioration and an increase in thrombo-embolic risk. Therapeutic options targeting atrial fibrillation in heart failure patients include pharmacological and non-pharmacological means. Pharmacological therapy is directed at either rate control using nodal blocking agents or rhythm control using anti-arrhythmic agents, of which the options are limited in patients with heart failure. The landmark AF-CHF trial did not show any benefit of rhythm control strategy as opposed to rate control in patients with heart failure and atrial fibrillation. However, patients in this trial as well as in others used mostly amiodarone for rhythm control. This might have negated any positive effects of achieving normal sinus rhythm. Non-pharmacological therapy both for rate and rhythm control is appealing. This includes AV node ablation for rate control, catheter ablation of atrial fibrillation and surgical therapy of atrial fibrillation. This review will address non-pharmacologic treatment of AF in heart failure patients.

The ratio of early transmitral flow velocity (E) to early mitral annular velocity (Em) predicts improvement in left ventricular systolic and diastolic function 1 year after catheter ablation for atrial fibrillation

AIMS

Successful rhythm control after atrial fibrillation catheter ablation is known to induce left atrial reverse remodelling and improve left ventricular (LV) function. We explored the clinical factors affecting LV systolic and diastolic function 1-year after catheter ablation for atrial fibrillation.

METHODS AND RESULTS

We compared pre-procedural and 1-year follow-up echocardiograms in 521 patients with atrial fibrillation who underwent catheter ablation. Left ventricular systolic function was estimated by the ejection fraction (EF); diastolic function was estimated by the ratio of early transmitral flow velocity (E) to early mitral annular velocity (Em). (i) Catheter ablation of atrial fibrillation significantly reduced left atrium volume index (P < 0.001) and improved LV EF both in patients with recurrent atrial fibrillation (n = 133, P = 0.008) and those without recurrence (n = 388, P < 0.001). (ii) Follow-up EF was significantly improved in patients with baseline E/Em < 15 (n = 454, P < 0.001), whereas E/Em was significantly reduced in patients with pre-procedural E/Em ≥ 15 (n = 67, P = 0.008). (iii) Baseline E/Em < 15 (β = -3.854, 95% CI -5.99 to -1.72, P < 0.001), baseline EF <50% (β = 10.586, 95% CI 7.55 to 13.63, P < 0.001), and female (β = -1.726, 95% CI -3.36 to -0.10, P = 0.038) were independently associated with improved EF. Baseline E/Em ≥ 15 (β = 4.896, 95% CI 3.45 to 6.34, P < 0.001) and younger age (β = -0.066, 95% CI -0.11 to -0.02, P = 0.003) were independent factors associated with improved E/Em.

CONCLUSION

Pre-procedural E/Em predicted improvement in LV systolic and diastolic functions 1 year after catheter ablation for atrial fibrillation. Low baseline E/Em was independently associated with improved EF, while high E/Em predicted improvement in LV diastolic function.

Atrial fibrillation: effects beyond the atrium?

Atrial fibrillation (AF) is the most common sustained clinical arrhythmia and is associated with significant morbidity, mostly secondary to heart failure and stroke, and an estimated two-fold increase in premature death. Efforts to increase our understanding of AF and its complications have focused on unravelling the mechanisms of electrical and structural remodelling of the atrial myocardium. Yet, it is increasingly recognized that AF is more than an atrial disease, being associated with systemic inflammation, endothelial dysfunction, and adverse effects on the structure and function of the left ventricular myocardium that may be prognostically important. Here, we review the molecular and in vivo evidence that underpins current knowledge regarding the effects of human or experimental AF on the ventricular myocardium. Potential mechanisms are explored including diffuse ventricular fibrosis, focal myocardial scarring, and impaired myocardial perfusion and perfusion reserve. The complex relationship between AF, systemic inflammation, as well as endothelial/microvascular dysfunction and the effects of AF on ventricular calcium handling and oxidative stress are also addressed. Finally, consideration is given to the clinical implications of these observations and concepts, with particular reference to rate vs. rhythm control.

Catheter Ablation of Atrial Fibrillation in Patients With Left Ventricular Systolic Dysfunction

Background—

Catheter ablation of atrial fibrillation (AFCA) is an established therapeutic option for rhythm control in symptomatic patients. Its efficacy and safety among patients with left ventricular systolic dysfunction is based on small populations, and data concerning long-term outcome are limited. We performed this meta-analysis to assess safety and long-term outcome of AFCA in patients with left ventricular systolic dysfunction, to evaluate predictors of recurrence and impact on left ventricular function.

Methods and Results—

A systematic review was conducted in MEDLINE/PubMed and Cochrane Library. Randomized controlled trials, clinical trials, and observational studies including patients with left ventricular systolic dysfunction undergoing AFCA were included. Twenty-six studies were selected, including 1838 patients. Mean follow-up was 23 (95% confidence interval, 18–40) months. Overall complication rate was 4.2% (3.6%–4.8%). Efficacy in maintaining sinus rhythm at follow-up end was 60% (54%–67%). Meta-regression analysis revealed that time since first atrial fibrillation ( P =0.030) and heart failure ( P =0.045) diagnosis related to higher, whereas absence of known structural heart disease ( P =0.003) to lower incidence of atrial fibrillation recurrences. Left ventricular ejection fraction improved significantly during follow-up by 13% ( P <0.001), with a significant reduction of patients presenting an ejection fraction <35% ( P <0.001). N-terminal pro-brain natriuretic peptide blood levels decreased by 620 pg/mL ( P <0.001).

Conclusions—

AFCA efficacy in patients with impaired left ventricular systolic function improves when performed early in the natural history of atrial fibrillation and heart failure. AFCA provides long-term benefits on left ventricular function, significantly reducing the number of patients with severely impaired systolic function.

Catheter ablation of atrial fibrillation in patients with concomitant left ventricular impairment: a systematic review of efficacy and effect on ejection fraction

INTRODUCTION

Catheter ablation of atrial fibrillation (AF) is an established rhythm control strategy; however, the impact of co-existing LV systolic dysfunction (LVSD) on ablation success is less well understood. This systematic review compiles the outcomes of catheter ablation of atrial fibrillation in patients with LVSD.

METHODS

An electronic database (Pubmed, Scopus, Embase) search using the keywords 'atrial fibrillation AND ablation AND (ventricular dysfunction OR heart failure OR cardiomyopathy)' was performed for English scientific literature up to 01/01/2014. 2484 references were retrieved and evaluated for relevance by three reviewers. Reviews and reference lists of retrieved articles were also examined to ensure all relevant studies were included. Data was extracted from 19 studies, including a total of 914 patients.

RESULTS

Single-procedure success in LVSD patients for AF ablation was 56.5% (95% CI: 48%-64%). Overall multiple-procedure (including the use of anti-arrhythmic drugs) in LVSD patients for AF ablation was 81.8% (95% CI: 75%-87%). The mean increase in LVEF following AF ablation was 13.3% (95% CI: 10.8%-15.9%). Seven studies reported improvements in exercise capacity and quality of life information using standardised criteria. The pooled rate of serious adverse events was 5.5% (95% CI: 3.7%-8.1%).

CONCLUSIONS

Catheter ablation may be an effective therapy in AF patients with left ventricular systolic impairment, and can be associated with improvements in left ventricular function, quality of life, exercise capacity, and modest rates of serious adverse events.

Effects of radiofrequency catheter ablation on left ventricular structure and function in patients with atrial fibrillation: a meta-analysis

INTRODUCTION

Radiofrequency catheter ablation (RFCA) is an effective therapy for atrial fibrillation (AF). This study was designed to investigate the effects of RFCA on left ventricular (LV) structure and function in AF patients.

METHODS AND RESULTS

A systematic literature search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials was performed to identify trials involving changes of LV structure and function in AF patients undergoing RFCA. Effect size was expressed as weighted mean difference (WMD) with 95% confidence interval (CI). LV end-diastolic diameter (LVEDD), LV end-systolic diameter (LVESD), LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LV ejection fraction (LVEF) were estimated. A total of 21 trials including 1,135 participants were qualified for this meta-analysis. Compared to the baseline values, there were significant decreases in LVEDV (WMD, -6.39 ml; 95%CI, -12.46 to -0.33) and LVESV (WMD, -6.39 ml; 95%CI, -11.35 to -1.42) and a significant improvement in LVEF (WMD, 6.23%; 95%CI, 3.70 to 8.75), but no significant changes were observed in LVEDD (WMD, -0.64 mm; 95%CI, -2.40 to 1.13) and LVESD (WMD, -0.38 mm; 95%CI, -1.32 to 0.56) after RFCA. Subgroup analysis demonstrated that patients with low LVEF (WMD, 11.90%; 95%CI, 9.16 to 14.64) gained more benefits than those with normal LVEF (WMD, 1.56%; 95%CI, 0.38 to 2.74). Besides, patients with chronic AF (WMD, 10.96%; 95%CI, 4.92 to 17.01) improved more than those with paroxysmal AF (WMD, 1.93%; 95%CI, -0.27 to 4.12).

CONCLUSIONS

RFCA in AF patients could reverse LV structural remodeling and improve LV systolic function, especially in patients with low LVEF and chronic AF.

Cardiac Remodeling After Atrial Fibrillation Ablation

Radiofrequency catheter ablation procedures are considered a reasonable option for patients with symptomatic, drug refractory atrial fibrillation (AF). Ablation procedures have been reported to effectively restore sinus rhythm and provide long-term relief of symptoms. Both electrical and structural remodeling occurs with AF. A reversal of the electrical remodeling develops within 1 week after restoration to sinus rhythm following the catheter ablation. The recovery rate is faster in the right atrium than the left atrium. Reverse structural remodeling takes longer and is still present 2 to 4 months after restoration of sinus rhythm. The left atrial transport function also improves after successful catheter ablation of AF. Left atrial strain surveys from echocardiography are able to identify patients who respond to catheter ablation with significant reverse remodeling after ablation. Pre-procedural delayed enhancement magnetic resonance imaging is also able to determine the degree of atrial fibrosis and is another tool to predict the reverse remodeling after ablation. The remodeling process is complex if recurrence develops after ablation. Recent evidence shows that a combined reverse electrical and structural remodeling occurs after ablation of chronic AF when recurrence is paroxysmal AF. Progressive electrical remodeling without any structural remodeling develops in those with recurrence involving chronic AF. Whether progressive atrial remodeling is the cause or consequence during the recurrence of AF remains obscure and requires further study.

Management strategies in atrial fibrillation in patients with heart failure

Atrial fibrillation (AF) and heart failure (HF) frequently occur together, and their coexistence is associated with a poor prognosis. AF and HF share risk factors, but their relationship involves complex hemodynamic, neurohormonal, inflammatory, ultrastructural, and electrophysiologic processes that extend beyond epidemiological associations. The shared mechanisms underlying AF and HF have important implications for the treatment of AF in patients with HF. This article focuses on reviewing contemporary data as it pertains to AF management in patients with HF and provides insight into investigational therapies currently under development.