Catheter Ablation of Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with significant morbidity and cost.1 AF is seen across a wide spectrum of patients, from lone AF without structural heart disease, to the postoperative setting, to patients with significant left ventricular dysfunction and advanced heart failure. AF is clinically classified as paroxysmal ( 7 days or requiring intervention to restore sinus rhythm), longstanding persistent (>1 year), or permanent, when restoration of sinus rhythm is no longer pursued.2The presence of AF is associated with increased mortality, and treatment of patients requires symptom relief and prevention of thromboembolism. Optimal antithrombotic therapy is determined on the basis of stroke risk as predicted by the CHADS2 scoring system (a system that awards 1 point each for congestive heart failure, hypertension, age ≥75 years, and diabetes mellitus and 2 points for prior stroke or transient ischemic attack).3,4 More recently, a modified scoring system, CHA2DS-VASC2, has been shown to improve risk prediction for patients previously thought to be at low risk for thromboembolic events.5Large-scale randomized trials have not shown mortality reduction with a rhythm control strategy compared with a rate control strategy6; however, many patients continue to have symptoms despite adequate rate control. For these patients, 3 therapeutic options are available for AF: (1) Antiarrhythmic drug therapy, (2) catheter ablation, and (3) surgical intervention (Maze procedure). Antiarrhythmic drug therapy has limited efficacy (40%–60%) and important side effects and has been shown to be less effective than catheter ablation in multiple comparative studies.7 In this Clinician Update, we illustrate current ablation strategies used to treat paroxysmal and persistent AF in the electrophysiology laboratory.A 57-year-old man with a history of hypertension presented with palpitations for 2 …