Current Hot Potatoes in Atrial Fibrillation Ablation

Atrial fibrillation (AF) ablation has evolved to the treatment of choice for patients with drug-resistant and symptomatic AF. Pulmonary vein isolation at the ostial or antral level usually is sufficient for treatment of true paroxysmal AF. For persistent AF ablation, drivers and perpetuators outside of the pulmonary veins are responsible for AF maintenance and have to be targeted to achieve satisfying arrhythmia-free success rate. Both complex fractionated atrial electrogram (CFAE) ablation and linear ablation are added to pulmonary vein isolation for persistent AF ablation. Nevertheless, ablation failure and necessity of repeat ablations are still frequent, especially after persistent AF ablation. Pulmonary vein reconduction is the main reason for arrhythmia recurrence after paroxysmal and to a lesser extent after persistent AF ablation. Failure of persistent AF ablation mostly is a consequence of inadequate trigger ablation, substrate modification or incompletely ablated or reconducting linear lesions. In this review we will discuss these points responsible for AF recurrence after ablation and review current possibilities on how to overcome these limitations.     

Approaches to Catheter Ablation of Nonparoxysmal Atrial Fibrillation

Purpose of review

We describe the technical aspects and outcomes of several different ablation strategies for nonparoxysmal (persistent and long-standing persistent) atrial fibrillation (AF) and discuss our ablation strategy for these patients.

Recent findings

Catheter ablation is an effective treatment strategy for patients with AF. Outcomes of ablation in patients with nonparoxysmal forms of AF tend to be worse than in patients with paroxysmal AF. Several recent studies have examined the long-term ablation success rates of different ablation approaches in patients with nonparoxysmal AF. While observational studies have suggested benefit of several different ablation strategies for persistent AF, large randomized controlled studies have shown similar success rates with pulmonary vein isolation (PVI) alone as compared versus PVI plus additional ablation.

Summary

The optimal ablation strategy to achieve long-term freedom from recurrent arrhythmias in patients with nonparoxysmal AF remains controversial. Achieving durable PVI should be the cornerstone of AF ablation. Additional large-scale randomized controlled studies are necessary to determine whether additional ablation might result in improved long-term ablation success rates in these patients.

     

Quality of life evidence in the management of the individual patient with atrial fibrillation

It is remarkable that in patients with paroxysmal AF not sufficiently controlled by pharmacological therapy, ablation and pacemaker treatment is highly effective and superior to drug therapy in controlling symptoms and improving quality of life. The discontinuation of drug therapy exposes patients to further recurrences of paroxysmal AF and the risk of developing permanent AF. However, both pharmacological and electrical treatment can enhance quality of life in AF patients.Long-term survival after ablation of the atrioventricular node and implantation of a permanent pacemaker in patients with AF is similar for AF patients whether they receive ablation or drug therapy; i.e. control of the ventricular rate by ablation of the atrioventricular node and permanent pacing do not adversely affect long-term survival.     

Atrial fibrillation in the aging heart: pharmacological therapy and catheter ablation in the elderly

The majority of patients with atrial fibrillation (AF) seeking medical treatment are in the elderly age group and the management of these patients is often complicated by comorbidities, challenging the pharmacological management of these patients. Owing to hypertension, congestive heart failure, left ventricular hypertrophy and coronary artery disease, antiarrhythmic treatment often fails due to side effects, proarrhythmia or poor rhythm control. In recent years, radiofrequency catheter ablation has been widely performed as an effective treatment for recurrent, drug-refractory AF. However, few elderly patients were included in prior AF catheter ablation studies and the current guidelines for catheter ablation of AF recommend a conservative approach in the elderly population owing to the absence of clinical data. However, study results from our group and others suggest that catheter ablation is a safe and effective treatment for patients over the age of 65 years with symptomatic, drug-refractory AF and, therefore, patients should not be excluded from catheter ablation on the basis of age alone. In this article, we discuss the pharmacological (rhythm control, rate control and anticoagulation) and catheter management of AF in the elderly population.     

Efficacy, safety, and outcome of atrial fibrillation ablation in septuagenarians

Aims: Catheter ablation is an effective treatment for atrial fibrillation (AF). The outcome of AF ablation in septuagenarians is not clear. Our aim was to evaluate success rate, outcome, and complication rate of AF ablation in septuagenarians.
Methods and Results: We collected data from 174 consecutive patients over 75 years of age who underwent AF ablation from 2001 to 2006. AF was paroxysmal in 55%. High-risk CHADS score (≥2) was present in 65% of the population. Over a mean follow-up of 20 ± 14 months, 127 (73%) maintained sinus rhythm (SR) with a single procedure, whereas 47 patients had recurrence of AF. Twenty of them had a second ablation, successful in 16 (80%). Major acute complications included one CVA and one hemothorax (2/194 [1.0%]). During the follow-up, three patients had a CVA within the first 6 weeks after ablation. Warfarin was discontinued in 138 out 143 patients (96%) who maintained SR without AADs with no embolic event occurring over a mean follow-up of 16 ± 12 months.
Conclusion: AF ablation is a safe and effective treatment for AF in septuagenarians.     

Is pulmonary vein isolation enough for persistent atrial fibrillation?

Pulmonary vein isolation (PVI) is a well‐established treatment for atrial fibrillation (AF); however, studies report suboptimal outcomes in persistent AF. Adjuvant ablation targeting the substrate outside the pulmonary veins has been proposed to improve the success rates of the procedure. In this review, we summarize the current evidence regarding additional ablation over PVI in persistent AF. We describe the different approaches for adjuvant ablation, outcomes, and future perspectives.     

Reality of surgical treatment of atrial fibrillation in the Czech Republic – Data from the National Register of Cardiac Surgery (2010–2015)

IntroductionSurgical ablation is an established treatment for atrial fibrillation (AF) in certain patients indicated for cardiac surgery. However, several strategies and approaches exist at different centers and no recent reports exist about current trends in AF treatment in the Czech Republic. We examined the national trends of concomitant and stand-alone surgical ablation of AF.MethodsData from the National Register of Cardiac Surgery and from a special questionnaire, created especially for this analysis, were used for evaluation of trends in the rate of concomitant surgical ablations in AF patients, rates of different concomitant procedures, and to analysis those factors that surgeons routinely used to reject AF treatment during cardiac surgery. Data about stand-alone AF surgery were also gathered and analyzed. The study period lasted from 2010–2015.ResultsOverall, 54% of cardiac surgery patients with history of AF received a concomitant surgical ablation procedure; this percentage declined slightly over the study period from 59% in 2010 to 51% in 2015. Concomitant ablation was most often performed on mitral valve patients (71%) and least often during isolated coronary revascularization (40%). In a multivariant analysis, age, history of myocardial infarction, history of cardiac surgery, renal failure, severe systolic dysfunction of the left ventricle (i.e., ejection fraction ≤30%), and preoperative hemodynamic instability were identified as strongest independent factors that causes surgeons to reject AF treatment during an non-AF cardiac surgery. Stand-alone AF surgery was performed in 9 (75%) Czech centers during the study period with a total of 132 procedures; this method has been abandoned by most centers, while several have switched to a hybrid ablation (HA) strategy. Hybrid ablation programs were ongoing in 5 centers in 2016, the overall number of procedures through the end of 2015 was 144.ConclusionsThe prevalence of surgical AF treatment in cardiac surgery patients has been slightly decreasing, and in almost half of the patients AF was left untreated. Stand-alone AF surgery has been nearly abandoned, while hybrid treatment has slowly expanded in Czech centers.     

心房颤动导管消融术后复发的危险因素分析

心房颤动是最常见的心律失常之一。导管消融已经成为心房颤动的有效治疗手段,具有较高的手术成功率,特别是阵发性心房颤动,术后成功率更高。然而,导管消融术后复发仍不少见,特别是慢性心房颤动。影响心房颤动经导管消融术后复发的危险因素是多方面的,包括体重、年龄、心房颤动持续时间、炎症、心房纤维化、左房疤痕、左房大小等,识别这些危险因素对指导个体化治疗及提高导管消融的成功率有一定的意义。因此,现对这些危险因素与心房颤动导管消融术后复发的关系做一综述。     

Technology insight: catheter ablation of the pulmonary veins in the treatment of atrial fibrillation

Over the past 5 years, catheter ablation of atrial fibrillation (AF) has evolved from being an experimental procedure to one that is performed in most large medical centers throughout the world. The rapid and widespread acceptance of this procedure reflects encouraging reports of the safety and efficacy of a pulmonary vein (PV) approach, which has 70-80% efficacy and around a 5% risk of major complications. Currently three PV-based ablation strategies are employed for catheter ablation of AF, termed segmental PV isolation, circumferential PV ablation and circumferential PV isolation. Three main research activities are ongoing in the field of catheter ablation of AF. One aim is to better define the safety and efficacy of AF ablation using the three approaches listed. The second research focus is to improve safety and efficacy by the development of new mapping and ablation tools. And the third major area of research is the development of new strategies for AF ablation. It is highly likely during the next 5 years that catheter ablation of AF will become a routine and well-accepted treatment strategy for this common arrhythmia condition.     

Cryoballoon ablation versus radiofrequency ablation for atrial fibrillation

Catheter ablation (CA) provides the most effective treatment option for patients suffering from symptomatic atrial fibrillation (AF). The procedural cornerstone of all ablation strategies and for all entities of AF is the electrical isolation of the pulmonary veins (PV). CA with the use of radiofrequency (RF) in conjunction with a 3-dimensional electroanatomical mapping system is the most established ablation approach, but it demands a long learning curve and recurrences of AF are commonly the result of recovered PV conduction. As a consequence, novel ablation systems such as the Cryoballoon (CB) have been evolved aiming at facilitation and increased efficacy of pulmonary vein isolation (PVI). CB ablation is characterized by a short learning curve as well as short procedure times and demonstrated non-inferiority with regard to safety and efficacy when being directly compared to RF ablation for treatment of paroxysmal AF. However, RF ablation is first choice for treatment of persistent AF, in particular when expanded ablation strategies beyond PVI are intended in order to improve clinical outcomes.     

进一步推进我国导管消融治疗心房颤动的临床研究

目前,心房颤动（房颤）治疗的研究方向主要有两个,一是导管消融,电生理学家力图通过不断改进消融术式,获取更好的消融效果,以期达到最终根治房颤的目的;二是药物治疗,许多药理学家则希望研制出副作用小、见效快、能长期抑制房颤的抗心律失常药物（AAD）,部分对导管消融治疗房颤效果有疑虑的临床医师也对此抱有很大希望。     

Catheter Ablation as First-Line Therapy for Atrial Fibrillation: Ready for Prime-Time?

Current guidelines include atrial fibrillation (AF) catheter ablation as part of the management strategy in patients that have failed at least one oral antiarrhythmic drug treatment course. However, growing evidence derived from both randomized and non-randomized studies demonstrate lower rates of AF recurrence and AF burden in patients with paroxysmal AF that are naïve to antiarrhythmic drug treatment. Furthermore, progression from paroxysmal AF to persistent AF appears to be delayed by early catheter ablation of AF. The current review addresses the question of the best timing for ablation in patients with paroxysmal AF and provides the rationale for offering AF ablation as first-line therapy based on the most updated evidence available.     

Catheter ablation of atrial fibrillation. -State of the Art-

Atrial fibrillation (AF) is an arrhythmia associated with increased morbidity and mortality. Since the first report of catheter ablation curing AF, numerous techniques have evolved, from linear ablation to segmental pulmonary vein (PV) isolation, to extensive encircling PV isolation, to left atrial (LA) linear ablation, to ablation of complex fragmented atrial electrograms (CFAEs) and ablation of ganglionated plexi. A new approach for complete isolation of the posterior LA, including all PVs, is box isolation. PV isolation is associated with a high clinical success rate in paroxysmal AF. However, in persistent AF or longstanding persistent AF, PV isolation only may not be sufficient, so additional ablation at sites with CFAEs is needed to improve the clinical outcome. A hybrid approach of combining PV isolation plus CFAE ablation is highly effective in the majority of patients with persistent AF or longstanding persistent AF. Thus, AF ablation is an effective and established treatment for AF that offers an excellent chance of a lasting cure. It is about time that AF ablation became a first-line therapy for selected patients with AF.     

Adjunct ablation strategies for persistent atrial fibrillation—beyond pulmonary vein isolation

Atrial fibrillation (AF) is the most common sustained arrhythmia. Recent guidelines recommend pulmonary vein isolation (PVI) as the main procedural endpoint to control recurrent AF in symptomatic patients resistant to antiarrhythmic drugs. The efficacy of such procedure is higher in paroxysmal AF while is still unsatisfactory in persistent and long-standing persistent AF. This review will summarize the state-of-the-art of AF ablation techniques in patients with persistent AF, discussing the evidence underlying different approaches with a particular focus on adjunctive ablation strategies beyond PVI including linear ablation, ablation of complex fractionated atrial electrograms (CFAE), ablation of ganglionated plexi, dominant frequency, rotors and other anatomical sites frequently involved in AF triggers.     

Complications of Catheter Ablation of Atrial Fibrillation: Cause, Prevention and Management

It has been reported that curative catheter ablation for atrial fibrillation (AF) can significantly reduce AF recurrence, and improve the morbidity and mortality of the AF patients, compared with medical treatment. However, a variety of complications of catheter ablation of AF have been reported, and some of them are fatal in patients with structurally normal hearts. There remain unsolved safety issues concerning AF ablation, before the catheter ablation is established as first-line therapy, even for selected patients in experienced centers. In this article, a variety of complications are reviewed and their prevention and treatment are discussed.     

Efficacy of repeat pulmonary vein isolation procedures in patients with recurrent atrial fibrillation

INTRODUCTION: Pulmonary vein (PV) isolation is effective in the treatment of most patients with atrial fibrillation (AF). Some advocate the addition of linear ablation techniques to improve efficacy; however, previous studies suggest recurrent PV conduction is responsible for AF recurrence. The aim of this study was to determine the effectiveness of repeat PV isolation in patients with recurrent AF after an initial ablation procedure and to determine if any patient characteristics predict failure of repeat PV isolation procedures. METHODS AND RESULTS: Seventy-four patients with two or more AF ablation procedures using selective PV isolation were included. PV isolation was guided with multielectrode ring catheter recordings, electroanatomic mapping, and intracardiac electrocardiography. Radiofrequency energy was delivered using a 4-mm-tip catheter (maximum 40 W, 52 degrees C); cooled-tip ablation was performed in 10 patients. Linear ablation was not performed. Antiarrhythmic drugs were continued for at least 6 weeks after ablation; AF episodes during this period were censored. Reconnection of one or more segments of previously ablated PVs was observed in 97% of patients; reconnected PVs served as the trigger for AF in 77%. Repeat PV isolation resulted in AF control (cure or 90% reduction in AF episodes) in 64 patients (86%) over a follow-up period of 9.1 +/- 6.7 months. "High-risk" characteristics such as left atrial enlargement, persistent AF, or mitral regurgitation did not predict failure of repeat PV isolation procedures. CONCLUSION: Recurrent AF following selective PV isolation is overwhelmingly associated with PV electrical reconnection. Repeat PV isolation without linear ablation provides effective treatment for recurrent AF in patients in whom an initial PV isolation procedure failed, independent of clinical characteristics.     

70岁以上心房颤动患者导管射频消融治疗临床分析

目的 分析70岁以上心房如动(房颤)患者导管射频消融治疗成功率及术后复发危险因素.方技,选择导管射频消融的70岁以上房颤患者107例,收集患者临床和电生理资料,采用Cox比例风险回归模型分析房颤消融术后复发危险因素.结果 107例患者中,阵发性房颤89例.持续性房颤18例.平均随访(25.2±11.5)个月,单次消融成...     

Patientenselektion zur Katheterablation von Vorhofflimmern: von paroxysmal bis lang andauernd

Atrial fibrillation (AF) is the arrhythmia that causes most arrhythmia-associated hospitalisations in the western world. In Germany it affects approximately 3 million people. The limited success rates of drug treatment stimulated an exploration of interventional treatment options for AF. As our knowledge on initiating triggers and perpetuating substrate of AF expanded, catheter ablation techniques have been developed. In this article we review the patient selection criteria according to the current guidelines, and discuss established and recently found risk factors for recurrences of AF and complications by catheter ablation that may influence current patient selection for catheter ablation of AF.     

Acute effects and long-term outcome of pulmonary vein isolation in combination with electrogram-guided substrate ablation for persistent atrial fibrillation

Complex fractionated atrial electrographic (CFAE) catheter ablation is a new approach for the treatment of atrial fibrillation (AF). It is unclear if acute results of this approach correspond to long-term outcome. The purpose of this study was to prospectively assess acute and long-term successes of an ablation approach combining pulmonary vein isolation (PVI) and ablation of CFAE areas for treatment of persistent AF. PVI and ablation of CFAE areas were performed in 35 patients with persistent AF (30 men, 57+/-9 years of age). At the end of the ablation procedure AF had terminated in 23 of 35 patients (66%) by conversion to sinus rhythm (8 of 23 patients, 35%) or organization to atrial tachycardia (15 of 23 patients, 65%). AF persisted in 12 of 35 patients (34%). At the end of the follow-up period (19+/-12 months), sinus rhythm was present in 26 of 35 patients (74%), including 9 patients with a repeat procedure. This group of 26 patients consisted of 7 of 8 patients (88%) with acute sinus rhythm after the first ablation, 11 of 15 patients (73%) with organization, and 8 of 12 patients (66%) with ongoing AF (p=0.32). In conclusion, a combined approach of PVI and CFAE ablation in persistent AF leads to acute AF termination in 66% and long-term maintenance of sinus rhythm in 74% of cases. However, long-term outcome was not predictable by acute results of the ablation procedure.     

心外膜射频消融治疗心房颤动的实验研究

目的 :探讨电学隔离肺静脉治疗心房颤动 (AF)的可行性和连续透壁径线的重要性。方法 :实验分为完全阻断组和未完全阻断组 ,每组犬各 7只。建立AF模型后 ,围绕肺静脉在心外膜进行射频消融。结果 :完全阻断组消融后AF持续时间与消融前比较差异有极显著性意义 (15 2 .7svs4 2 6 .3s ,P <0 .0 1) ;完全阻断组消融后在持续时间与未完全阻断组消融后比较差异也有极显著性意义 (15 2 .7svs 36 7.3s ,P <0 .0 1) ,而窦房结功能和房室传导功能无显著性变化。结论 :电学隔离肺静脉治疗AF是可行的 ,形成确切的连续透壁肺静脉损伤可简化消融治疗AF的径线。