Rhythm Control in Heart Failure Patients with Atrial Fibrillation

AF and heart failure (HF) commonly coexist. Left atrial ablation is an effective treatment to maintain sinus rhythm (SR) in patients with AF. Recent evidence suggests that the use of ablation for AF in patients with HF is associated with an improved left ventricular ejection fraction and lower death and HF hospitalisation rates. We performed a systematic search of world literature to analyse the association in more detail and to assess the utility of AF ablation as a non-pharmacological tool in the treatment of patients with concomitant HF.

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.

Comparison of Amiodarone and Propafenone in Blanking Period after Radiofrequency Catheter Ablation in Patients with Atrial Fibrillation: A Propensity Score-Matched Study

Background. Amiodarone and propafenone are commonly used to maintain sinus rhythm in patients with atrial fibrillation (AF). However, it is not known which one is better in reducing early recurrence (ER) during the blanking period (the first three months after catheter ablation). Objective. To compare the efficacy and safety of amiodarone and propafenone in reducing ER during the blanking period after radiofrequency catheter ablation (RFCA) in AF patients. Materials and Methods. A total of 694 patients who underwent their first RFCA between May 2014 and May 2018 were enrolled in this retrospective study. Subsequently, 202 patients were excluded according to the exclusion criteria. The remaining 492 patients were divided into two groups based on the choice of antiarrhythmic drugs (AADs) (amiodarone or propafenone) in the blanking period. The primary outcomes were incidence of ER and AAD-associated adverse effects during the blanking period after RFCA. Propensity score matching (PSM) analyses were used to compare the outcomes of the two groups while controlling for confounders. Results. Among the 492 patients who took AADs in the blanking period (187 amiodarone and 305 propafenone), PSM selected 135 unique pairs of patients with similar characteristics. Amiodarone was associated with a lower ER incidence rate (23.7% versus 48.9%, p<0.001) and a similar rate of AAD-associated adverse effects (2.1% versus 1.5%, p=0.652). Treatment with amiodarone in the blanking period was significantly associated with a lower ER incidence rate compared to treatment with propafenone (HR=0.416, 95% CI 0.272–0.637, p<0.001). Conclusions. Compared with propafenone, amiodarone was associated with a lower ER incidence rate, and they had similar rates of AAD-associated adverse effects. Treatment with amiodarone in the blanking period was shown to be more effective in reducing ER than propafenone.

Strategies to Improve the Outcome of Cryoballoon Ablation in the Treatment of Atrial Fibrillation

Atrial fibrillation (AF) is a common arrhythmia contributing to severe outcomes, including cardiac dysfunction and stroke, and it has drawn great attention around the world. Drug therapies have been available for many years to terminate AF and control heart rate. However, the results from clinical studies on drug therapies have been discouraging. Mounting evidence indicates that radiofrequency catheter ablation (RFCA) is a safe and effective method to maintain sinus rhythm, especially in patients who are drug intolerant or for whom the drugs are ineffective, although it is a technically demanding and complex procedure. Fortunately, a novel application, cryoballoon ablation (CBA), with outstanding characteristics has been widely used. Great outcomes based on CBA have manifested its significant role in the treatment of AF. However, how to improve the safety and efficacy of CBA is a question that has not been well-answered. Would it be helpful to develop a different generation of cryoballoon? Is bonus freezing beneficial, or not? Is it better to prolong freezing time? Dose CBA combined with RFCA bring higher success rates? In this review, we comprehensively summarized useful applications for improving outcomes of CBA in AF patients.

Characteristics and outcomes of patients after multiple (≥3) catheter ablation procedures for atrial fibrillation

Background: Many atrial fibrillation (AF) patients require more than one radiofrequency catheter ablation (RFCA) procedure to maintain sinus rhythm. This study aimed to evaluate risk and risk factors of atrial tachyarrhythmia (ATa) recurrence in patients undergoing multiple (≥3) RFCA procedures for AF. Methods: This single-center, retrospective, observational study enrolled 118 consecutive patients who underwent multiple ablation procedures for paroxysmal and non-paroxysmal AF with circumferential pulmonary vein ablation (CPVA), and bidirectional block of lines with disappearance of complex fractionated atrial electrograms (CFAEs) as index procedural endpoints, respectively. Results: At a median follow-up of 18 (range, 6-91) months after the last procedure (mean, 3.2 procedures), freedom from ATa recurrence was 40.7% (48/118). Initially diagnosed non-paroxysmal AF (P=0.039), baseline LA size (P=0.044), and recurrent AF after the second procedure (P=0.044) were univariate predictors of ATa recurrence, while only the latter (P=0.010) was an independent multivariate predictor (hazard ratio for ATa recurrence of 1.88 [95% CI, 1.16-3.05]. Conversion of recurrent types between AF and AFL/AT occurred in 52.9% (37/70) of patients with ATa recurrence, and 29.2% (14/48) of patients with sinus rhythm after last procedure. Few patients (7.8% [20/257]) recovered PV potential induced recurrent ATa during multiple procedures, and most (87.6% [141/161]) were bystanders of recurrent ATa. Conclusions: Multiple (>3) RFCA for paroxysmal or non-paroxysmal AF yielded unsatisfactory ATa recurrence rates with recurrent AF after the second procedure as multivariate predictor and recovered PV potential as a bystander commonly as underlying mechanism. Conversion of recurrent types between AF and AFL/AT was common.

Abstract 148: Observational Study of Efficacy of Low-Dose Amiodarone

Importance: Atrial fibrillation (AF) is the most common rhythm abnormality of the heart and is projected to double between 2010 and 2030. Many patients with AF remain symptomatic after rate control with medications and hence need anti-arrhythmic medications to maintain sinus rhythm. Among the multiple medications to prevent AF recurrence, amiodarone (AM) is the most effective. AM and dofetilide are the only 2 medications approved to prevent recurrence of AF in patients with left ventricular dysfunction. Most papers considered “low dose” AM to be between 200 and 300 mg daily. Even a recent review in a major journal recommended maintaining sinus rhythm (SR) with AM 200 to 300 mg daily. Two very small studies from China showed AM 100 mg to be effective. A recent unpublished report by McGrew demonstrated the impressive effectiveness of 100 mg or less of AM to prevent recurrence of AF. Objective: To determine the known AF free interval after first identification of receiving 100 mg AM or less to prevent recurrence of AF. Methods: An observational retrospective chart review of randomly selected adult patients identified to be taking AM 100 mg for AF recurrence for at least 2 months at Charleston Area Medical Center (CAMC) or community clinics during January 1, 2008 to June 30, 2014. Results: Fifty-one patients who were taking AM ≤ 100 mg were identified. Mean duration of apparent AF free continuous treatment was 25.2 ± 23.3 months. AM was decreased in 4% (2 of 51) patients and stopped in 31% (16 of 51) patients for AF recurrence, perceived side effect or unknown reasons. SR was maintained for 25.7 ± 27.7 months. Conclusion: This small study showed that very low dose AM is commonly used in the community and appears to be an effective option for AF prophylaxis. It is important, the providers selecting medications to prevent recurrence of AF be aware of this option.

How to Prevent, Detect and Manage Complications Caused by Cryoballoon Ablation of Atrial Fibrillation

Atrial fibrillation is the most common cardiac arrhythmia and the prevalence is increasing every year. Patients who fail to maintain sinus rhythm with use of anti-arrhythmic drug therapy are referred for catheter ablation. Cryoballoon (CB) ablation has emerged as an effective and alternative treatment option to traditional point-by-point radiofrequency ablation, but there can be complications. This article reviews the incidence, presentation, risk factors, management and preventative strategies of three major complications associated with CB ablation: phrenic nerve injury, atrial oesophageal fistula and bronchial injury. Although these complications are rare, electrophysiologists should institute measures to identify high-risk patients, implement best-practice techniques to minimise risks and maintain a high index of suspicion to recognise the complications quickly and implement correct treatment strategies.