Catheter Ablation of Atrial Fibrillation – Techniques and Technology

Abstract

Over the past decades catheter ablation of atrial fibrillation (AF) has evolved from being a largely experimental procedure to a well-established therapeutic option for certain patients with AF. [1][2][3][4] Currently the backbone of most catheter ablation techniques is to target the pulmonary veins (PVs) in order to achieve their electrical isolation and maintain sinus rhythm (SR).1 Additional techniques may be used to ablate non-PV triggers and candidate atrial sites considered responsible for maintaining AF.1 Drawing upon our experience and our literature review, we would estimate the single procedure efficacy of AF ablation in an "optimal" candidate for AF ablation to be between 60 % and 80 %. The single procedure in a less optimal patient, such as a patient with persistent AF, lies between 50 % and 70 %. The single efficiency of the procedure in a suboptimal patient, such as a patient with continuous AF for four years, is 40 % or less. It is important to recognise that AF may recur following ablation and that patients may need a second procedure for which the success rate is cumulative.In this paper we will initially describe the reasons why we may consider catheter ablation as a treatment for AF. We will then discuss the current ways by which catheter ablation for AF is performed.We will review the relative efficency of ablation compared to other treatment options. Finally, we will discuss what the future may hold for AF ablation procedures and how these may impact on current success rates and safety of AF ablation. Rationale for Catheter Ablation of AFAs outlined by the HRS Consensus Document on AF ablation, the primary indication for AF ablation is the presence of symptomatic AF refractory, or intolerant, to at least one class 1 or 3 antiarrhythmic (AA) medication. 1 In specific situations, ablation may be considered as a first line treatment for AF; however this is not common practice.The most common reason to pursue catheter ablation for AF is to reduce the patient's AF burden. Therefore, ablation is performed to relieve symptoms and improve quality of life. 1-3,5 As of today, it remains uncertain whether maintaining SR affects patient survival and, especially, stroke risk. 6-13 However it appears that catheter ablation is more effective at maintaining SR as compared to AA therapy. Hopefully the CABANA study will provide insight into this and other important questions regarding the outcome of maintaining AF patients in SR by catheter ablation.Typically, higher procedural success rates are reported in patients with paroxysmal AF and minimal structural heart disease. 1,5 Yet published data also supports a role for catheter ablation in patients who were previously deemed unsuitable. Benefit from ablation has been reported in patients with heart failure 14-17 and long-standing persistent AF. Diagnostic Electrophysiology and Ablation AbstractFor certain patients with atrial fibrillation (AF) catheter ablation is now an important, therapeutic, intervention. It is established that catheter ablation is mo...

Mid-to-long-term recurrence of atrial fibrillation in surgical treatment vs. catheter ablation: a meta-analysis using aggregated survival data

“…AF is a potentially life-long condition with a variety of management options, all of varying invasiveness and effectiveness. Usually following the failure of rate control alone, as well as pharmacological rhythm control, the abnormal electrical activity is isolated from the pulmonary veins using a circumferential ablation ( 49 ). While many different types of lesion sets have been reported, including both endo- and epicardial ablation, there has been no consensus as to which pattern is most effective.…”

Reshaping Prognosis: Atrial fibrillation ablation in a case of severe tachycardiomyopathy in a young patient

“…Catheters are inserted from the right atrium through a transseptal puncture into the left atrium, and high-frequency energy sources, such as radiofrequency or cryotherapy, are utilized to electrically isolate the pulmonary veins from the rest of the left atrium and restore sinus rhythm. 16 Alternative ablation lines (such as roof lines or mitral isthmus lines) or targeting atrial areas exhibiting high degrees of fractionated atrial electrograms could be utilized; however, their efficacy in persistent AF ablation remains insufficiently quantified 17 .…”

Feeling a Little Blue After Ablation: Iatrogenic Atrial Septal Defect With Right-to-Left Shunt Following Atrial Fibrillation Ablation

“…Studies regarding risks for the development of a persistent iASD are currently limited [ 15 ]. Due to the possibility of a right-to-left shunt in patients with persisting defects, a screening methodology implemented before procedures may show benefits to prevent these adverse outcomes.…”