Predictors of recurrent atrial fibrillation following catheter ablation

ABSTRACT

Introduction

Atrial fibrillation (AF) is a complex and multi-factorial rhythm disorder. Catheter ablation is widely used for the management of AF. However, it is limited by relapse of the arrhythmia necessitating repeat procedures.

Areas covered

This review aims to discuss the predictors of post-ablation recurrent AF including age, gender, genetic predisposition, AF type and duration, comorbidities, lifestyle factors, echocardiographic parameters of heart chambers, left atrial fibrosis and ablation strategies and targets. An extensive literature search was undertaken on PubMed and Google Scholar to obtain full texts of relevant AF-related articles.

Expert opinion

Maintenance of stable sinus rhythm is the main intended outcome of AF ablation. Therefore, it is very crucial to identify the risk factors that may influence the ablation success. Most of these predictors such as comorbidities, ablation strategy and targets and lifestyle factors are either reversible or modifiable. Thus, not only the awareness of these known risk factors by both patients and their physicians but also future research to identify the unknown predictors are critical to optimize care in this multi-faceted morbidity.

KEYWORDS:

• Atrial Fibrillation
• catheter ablation
• comorbidities
• fibrosis
• lifestyle factors
• non-PV triggers
• recurrence

Article highlights

The article discusses known predictors of recurrent AF including

• Age and female sex are known predictors of AF recurrence. However, superior success can be achieved by targeting both PV and non-PV triggers for ablation in elderly and women. Moreover, the rate of thromboembolic complications can be reduced with appropriate peri- and post-procedural anticoagulation therapy in this vulnerable population.

• An association between genetic variants and response to ablation therapy has been reported by some studies. Further work is needed to understand the molecular mechanism underlying AF recurrence.

• AF being a progressive disease, non-paroxysmal AF type, and duration of AF are critical in influencing the ablation outcome. However, early intervention and implementation of optimal ablation strategies can improve the procedural success.

• Cardiorespiratory fitness and lowering the alcohol intake can improve the success rate of catheter ablation. However, in patients with persistent arrhythmia, AF burden substantially affect the intensity of physical activity making exercise almost unrealistic in patients with incessant arrhythmia.

• Comorbidities such as obesity, hypertension, diabetes, heart failure, metabolic syndrome, and obstructive sleep apnea are known predictors of AF recurrence. However, with aggressive control of these risk factors and appropriate ablation strategy, greater procedural success can be achieved.

• Ablation strategy is an independent predictor of ablation-outcome. In non-paroxysmal AF patients as well as in paroxysmal AF cases with very late recurrence, it is important to target both PV and non-PV triggers in order to accomplish long-term sinus rhythm.

• Failure to create durable transmural lesions is one of the main causes of post-ablation recurrence. New technologies are emerging that show promise in improving durability of lesions.

• Echocardiographic parameters such as left atrial (LA) diameter, LA volume, LA strain, and PV volume have been reported as predictors of arrhythmia recurrence.

• Pre-existent left atrial fibrosis is a strong predictor of AF recurrence. Association of extensive fibrosis with high prevalence of non-PV triggers could be the underlying mechanism for relapse of arrhythmia.

• Emerging evidences suggest the critical role of non-PV triggers, especially from coronary sinus and left atrial appendage, in very late arrhythmia recurrence in paroxysmal AF patients with permanently isolated PVs.

Declaration of interest

A Natale is a consultant for Abbott, Biosense Webster, Boston Scientific, Baylis, Biotronik and Medtronic. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.