Prognostic value of induction of atrial fibrillation before and after pulmonary vein isolation Christopher Adlbrecht a, ⁎, Marianne Gwechenberger a , Bernhard Richter a , Johann Sipötz a , Alexandra Kaider b , Heinz Gössinger a a Medical University of Vienna, Department of Internal Medicine II, Division of Cardiology, Vienna, Austria b Medical University of Vienna, Center for Medical Statistics, Informatics and Intelligent Systems, Section for Clinical Biometrics, Vienna, Austria abstract article info Article history: Received 23 February 2011 Received in revised form 20 May 2011 Accepted 3 July 2011 Available online xxxx Keywords: Atrial fibrillation Catheter ablation Inducibility Changes in inducibility Electrophysiology Background: Apart from pulmonary vein isolation, catheter ablation of atrial fibrillation (AF) lacks reliable electrophysiological endpoints. The present study investigated the prognostic value of changes in AF inducibility due to ablation. Methods: Between 10/2006 and 10/2009 121 patients referred for catheter ablation of symptomatic, drug refractory paroxysmal AF were included. Sinus rhythm immediately before ablation was a prerequisite for study entry. Two respective attempts to induce AF (N 1 min) by decremental coronary sinus stimulation before and after ablation were performed. Results: A total of 121 patients aged 59.5 ± 10.4 years undergoing pulmonary vein isolation due to paroxysmal AF were included. The median follow-up duration was 12.1 months [quartiles: 6.5–20.3 months]. In 36 (30%) patients AF was inducible before, but not after ablation. Forty-nine (41%) patients were neither inducible before nor after the procedure, whereas 25 patients (21%) displayed unchanged inducibility. In 11 patients (9%) AF was inducible only after ablation. Patients with inducibility solely after the ablation had the highest risk of AF recurrence (HR 6.71 [95%-CI 2.76–16.30], p = 0.0005) compared to patients without inducibility before and after the procedure. Conclusion: The results of attempted AF induction before and after ablation have significance with respect to ablation outcome. Both patient groups with either unchanged inducibility or facilitated induction after ablation had the highest recurrence rates of AF. © 2011 Elsevier Ireland Ltd. All rights reserved. 1. Background Catheter ablation of paroxysmal atrial fibrillation (AF) is recom- mended by current guidelines for symptomatic patients with failed antiarrythmic medication or without structural heart disease [1]. However, apart from pulmonary vein isolation, catheter ablation of AF lacks reliable electrophysiological endpoints. The role of inducibility of AF after radiofrequency catheter ablation has been examined by several investigators [2–10], but the prognostic value of changes in inducibility before and after radiofrequency catheter ablation has never been scrutinized. The aim of the present study was to investigate the prognostic value of changes in AF inducibility due to ablation. 2. Methods 2.1. Patients Between 10/2006 and 10/2009 121 patients referred for catheter ablation of symptomatic, drug refractory paroxysmal AF, were included into the present study. Exclusion criteria were persistent AF, absence of sinus rhythm immediately before the ablation procedure, pregnancy, ongoing infections, intracardiac thrombosis, inadequate anticoagulation prior to index admission, contraindicated oral anticoagulation, previous myocardial infarction or cardiac surgery within the last 3 months, and refusal to give written informed consent. The study was approved by the ethics committee of the Medical University of Vienna and was conducted in accordance with the Declaration of Helsinki. 2.2. Treatment before catheter ablation Oral anticoagulation with an international normalized ratio target of 2–3, or treatment with weight-adjusted low molecular weight heparin was given over a period of at least 1 month before the ablation procedure. Procedures before the ablation were performed as previously described [10]. 2.3. Catheter ablation procedure The procedures were performed applying intravenous sedation using midazolam and fentanyl. Vascular access was obtained through both femoral veins and two 7-french International Journal of Cardiology xxx (2011) xxx–xxx ⁎ Corresponding author at: Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria. Tel.: +43 1 40 400 4614; fax: +43 1 40400 4216. E-mail address: christopher.adlbrecht@meduniwien.ac.at (C. Adlbrecht). IJCA-13727; No of Pages 4 0167-5273/$ – see front matter © 2011 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijcard.2011.07.023 Contents lists available at ScienceDirect International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard Please cite this article as: Adlbrecht C, et al, Prognostic value of induction of atrial fibrillation before and after pulmonary vein isolation, Int J Cardiol (2011), doi:10.1016/j.ijcard.2011.07.023