Clinical predictors and relationship between early and late atrial tachyarrhythmias after pulmonary vein antrum isolation Sakis Themistoclakis, MD,* Robert A. Schweikert, MD, † Walid I. Saliba, MD, † Aldo Bonso, MD,* Antonio Rossillo, MD,* Giovanni Bader, MD,* Oussama Wazni, MD, † David J. Burkhardt, MD, † Antonio Raviele, MD,* Andrea Natale, MD, FHRS ‡ *From Cardiovascular Department, Umberto I Hospital, Mestre-Venice, Italy, † Section of Cardiac Pacing and Electrophysiology, Department of Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio, and ‡ Stanford University, Palo Alto, California. BACKGROUND Several studies have reported early (EAT) and late (LAT) atrial tachyarrhythmias following atrial fibrillation (AF) ab- lation, but the factors associated with them and their clinical significance are not well known. OBJECTIVE The purpose of this study was to investigate the predictors and the relationship between EAT and LAT after AF ablation. METHODS A total of 1298 patients with paroxysmal (54%), per- sistent (18%), or permanent (28%) AF underwent intracardiac echocardiography-guided pulmonary vein antrum isolation and were followed for 41  10 months. EAT and LAT were defined as an episode of AF or atrial flutter/tachycardia lasting longer than 1 minute that occurred within the first 3 months of ablation and after 3 months postablation, respectively. RESULTS After a single ablation procedure, EAT developed in 514 (40%) patients and LAT in 292 (22%) patients. At a multivariable analysis, longer AF duration (odds ratio [OR] 1.03), history of hypertension (OR 1.32), left atrial enlargement (OR 1.55), perma- nent AF (OR 1.72), and lack of superior vena cava isolation (OR 1.60) were significantly associated with EAT. Independent predic- tors of LAT were longer AF duration (OR 1.03), history of hyper- tension (OR 1.65), persistent (OR 2.17) or permanent AF (OR 2.28), and occurrence of EAT (OR 30.62). The risk of LAT was inversely related to the time to first EAT occurrence (OR 20, 54, and 1,052 in first, second, and third month, respectively). Nota- bly, 49% of patients with EAT did not experience LAT. CONCLUSION EAT strongly predict LAT. However, EAT did not automatically mean ablation failure. Delaying redo procedure may be appropriate during the first 2 months after ablation. Longer AF duration, hypertension, and nonparoxysmal AF are independent predictors of EAT and LAT. KEYWORDS Atrial fibrillation; Catheter ablation; Left atrial flutter; Pulmonary vein; Recurrences (Heart Rhythm 2008;5:679 – 685) © 2008 Heart Rhythm Society. All rights reserved. Introduction Atrial fibrillation (AF) is the most common sustained car- diac arrhythmia, with a prevalence between 0.9% and 2.5% in the general population and an increasing incidence with age. 1,2 The clinical significance and financial impact of AF management create a need for effective treatment. Antiar- rhythmic drugs for prevention of AF recurrences frequently are ineffective and often are associated with adverse and toxic effects that may nullify the possible benefit of sinus rhythm maintenance. In the last 10 years, left atrial catheter ablation aimed at pulmonary vein (PV) isolation and/or elimination of the arrhythmic substrate has been proposed as a definitive cure for this arrhythmia. 3 Some investigators have examined the incidence of AF after ablation and found that early arrhythmic recurrences (i.e., within the first 2 weeks to 3 months after the procedure) are common, oc- curring in as many as 50% of patients. 4–9 However, these recurrences often disappear after the initial period and do not necessarily indicate failure of the procedure over time. It is important to realize that these data derive from small series of patients with relatively short-term follow-up. Fur- thermore, the factors predictive of both early (EAT) and late atrial tachyarrhythmias (LAT) and their clinical relevance have not been thoroughly investigated. The aim of the present study was to identify the clinical variables associated with EAT and LAT and to assess the relationship between these arrhythmias in a very large co- hort of patients undergoing PV antrum isolation. Methods Patient population Consecutive patients referred to Cleveland Clinic Founda- tion, Cleveland, Ohio, USA, or Umberto I Hospital, Mestre- Venice, Italy, for treatment of AF by PV antrum isolation between September 2001 and June 2005 were included in Address reprint requests and correspondence: Dr. Antonio Raviele, Cardiovascular Department, Umberto I Hospital, 30174 Mestre-Venice, Italy. E-mail address: araviele@tin.it. (Received September 12, 2007; accepted January 19, 2008.) 1547-5271/$ -see front matter © 2008 Heart Rhythm Society. All rights reserved. doi:10.1016/j.hrthm.2008.01.031