Site Localization and Characterization of Pain During Radiofrequency Ablation of the Pulmonary Veins JAMSHID ALAEDDINI, M.D., MARK A. WOOD, M.D., BABER PARVEZ, M.D., VISHESH PATHAK, B.S., KRISTEN A. WONG, and KENNETH A. ELLENBOGEN, M.D. From the Division of Cardiology, Virginia Commonwealth University, Medical Center, Richmond, Virginia Background: Characteristics of radiofrequency (RF) lesions producing pain with an 8-mm catheter during pulmonary vein (PV) ablation have not been prospectively studied. Methods: We studied 46 (30 men, age 56 ± 10 years) patients with AF who underwent RF ablation of PVs. PV isolation was achieved by using an 8F, 8-mm Biosense TM ablation catheter (Biosense Webster, Diamond Bar, CA, USA) guided by intracardiac echocardiography (ICE). An electroanatomic map was used to document the location of all RF lesions and the time; PV location and maximum temperature of every lesion were recorded. Location of the esophagus was determined by magnetic resonance imaging prior to the procedure and by both ICE and barium swallows during procedure. Result: A total of 1,448 (33 ± 12) RF lesions were delivered to 180 veins. Thirty-nine patients (85%) had at least one lesion associated with pain (mean: 8 ± 5 lesions) during ablation. The RF generator setting during lesions resulting in pain sensation was 48.6 ± 7.0 Watts and 51.5 ± 2.9 ◦ C. Maximum temperature attained at the time of pain sensation was 45.7 ± 4.2 ◦ C. By logistic regression analysis the left superior PV (OR 1.54, CI 1.06–2.24, LS vs RI, P < 0.05) and left inferior PV (OR 2.74, CI 1.79–4.19, LI vs RI, P < 0.001) location were both positively correlated with the production of pain. The location of lesions associated with pain was not near the esophagus during any of the pain-producing lesions. Conclusion: Pain sensation is relatively common during RF ablation of PVs. There was no correlation between pain and the location of esophagus. Pain was more common during RF ablation of left inferior and left superior PVs. (PACE 2007; 30:1210–1214) atrial fibrillation, radiofrequency ablation, ganglionated plexi Background Recent advances demonstrating involvement of the pulmonary veins (PVs) in the pathophysiol- ogy of atrial fibrillation (AF) led to development of different ablative strategies for the treatment of AF. 1–3 Radiofrequency (RF) energy is the most common energy source used for left atrial antral ablation. 1–3 Many patients experience pain during RF ablation of the PVs similar to the pain experi- enced during ablation of other atrial tachyarrhyth- mias, particularly atrial flutter. 4–6 However, the incidence, time course, and temperature character- istics of pain produced during RF ablation of the PVs with an 8-mm catheter have not been prospec- tively described in humans. The purpose of this study was to prospectively evaluate the incidence and sites of pain during AF ablation with an 8-mm catheter. Methods Patient Population Between January 2005 and December 2005, 46 patients underwent RF ablation of AF using an 8F, Address for reprints: Kenneth A. Ellenbogen, M.D., Medi- cal College of Virginia, P.O. Box 980053, Richmond, Virginia 23298–0053. Fax: 804–828-6082; e-mail: kellenbogen@pol.net, kaellenb@vcu.edu, ken.ellenbogen@gmail.com Received March 6, 2007; revised July 7, 2007; accepted July 12, 2007. 8-mm tip Biosense TM ablation catheter (Biosense Webster, Diamond Bar, CA, USA) and data on all le- sions delivered were recorded. All patients signed a written informed consent. PV Isolation Procedure All patients underwent intracardiac echocar- diography (ICE) using a 9F, 10.5 MHz phased ar- ray ICE catheter (Acuson, Siemens Inc., TM Moun- tain View, CA, USA) imaging system introduced through the left femoral vein. 7 All PVs ostia were defined by ICE prior to transseptal puncture and their diameter was measured before and after ab- lation. Pulsed-wave Doppler flow velocities of all PVs were determined before and after ablation to assess for PV narrowing. Double transseptal punc- ture was performed under ICE guidance. A circu- lar mapping catheter (Lasso TM , Biosense Webster) was advanced to the antrum of each PV. PV an- giograms during adenosine-induced asystole was used to confirm PV antral localization with the ICE image. A quadripolar 8F, 8-mm tip ablation catheter (Biosense Webster), inserted through the right femoral vein sheath, was used to direct RF lesions around the antrum of each PV guided by electrical evidence of muscle sleeve extension as needed by the Lasso catheter. A Stockert genera- tor (Biosense Webster) was set to deliver RF le- sions up to 60 W and 52 ◦ C. Lesions were placed C 2007, The Authors. Journal compilation C 2007, Blackwell Publishing, Inc. 1210 October 2007 PACE, Vol. 30