BACKGROUND: Mitral isthmus is often targeted as a part of stepwise approach during radiofrequency ablation for persistent atrial ablation. Acute success rate in achieving the mitral isthmus block is only modest, late reconduction rate is relatively high and, consequently, incomplete lesion may be proarrhythmic. We describe the first-in-man experience with successful MI ablation by bipolar RF energy delivery. CASE PRESENTATION: A 64-year-old caucasian man after two previous ablation procedures for drug resistant atrial fibrillation in recent four years, which included pulmonary vein isolation and linear left atrial lesions, was referred for the treatment of recurrent perimitral flutter. Despite the third attempt to create bidirectional block at the mitral isthmus region, we were not even able to stop the arrhythmia by aggressive unipolar radiofrequency ablation both from the left atrium and coronary sinus, because of deeply embedded slow conducting channel probably around the vein of Marshall. Arrhythmia was finally terminated and the block was achieved by bipolar radiofrequency ablation between two irrigated-tip catheters positioned at the left atrial endocardium and contralaterally inside the coronary sinus. CONCLUSION: Bipolar radiofrequency energy delivery can be an option for ablation of perimitral flutter resistant to standard unipolar radiofrequency ablation. This may improve clinical outcome of patients undergoing non-pharmacological treatment for persistent atrial fibrillation. The safety and efficacy of this technique has to be confirmed in future studies.

Department of Cardiology Institute for Clinical and Experimental Medicine Vídeňská 1958 9 Prague 140 21 Czech Republic

Zobrazit více v PubMed

Wong KC, Betts TR. A review of mitral isthmus ablation. Indian Pacing Electrophysiol J. 2012;12(4):152–170. PubMed PMC

Sivagangabalan G, Barry MA, Huang K, Lu J, Pouliopoulos J, Thomas SP, Ross DL, Thiagalingam A, Kovoor P. Bipolar ablation of the interventricular septum is more efficient at creating a transmural line than sequential unipolar ablation. Pacing Clin Electrophysiol. 2010;33(1):16–26. doi: 10.1111/j.1540-8159.2009.02602.x. PubMed DOI

Nagashima K, Watanabe I, Okumura Y, Ohkubo K, Kofune M, Ohya T, Kasamaki Y, Hirayama A. Lesion formation by ventricular septal ablation with irrigated electrodes: comparison of bipolar and sequential unipolar ablation. Circ J. 2011;75(3):565–570. doi: 10.1253/circj.CJ-10-0870. PubMed DOI

Nagashima K, Watanabe I, Okumura Y, Sonoda K, Kofune M, Mano H, Ohkubo K, Nakai T, Kunimoto S, Kasamaki Y, et al. Epicardial ablation with irrigated electrodes: effect of bipolar vs. unipolar ablation on lesion formation. Circ J. 2012;76(2):322–327. doi: 10.1253/circj.CJ-11-0984. PubMed DOI

Koruth JS, Dukkipati S, Miller MA, Neuzil P, d’Avila A, Reddy VY. Bipolar irrigated radiofrequency ablation: a therapeutic option for refractory intramural atrial and ventricular tachycardia circuits. Heart Rhythm. 2012;9(12):1932–1941. doi: 10.1016/j.hrthm.2012.08.001. PubMed DOI

Kuck KH, Kunze KP, Schluter M, Geiger M, Jackman WM, Naccarelli GV. Modification of a left-sided accessory atrioventricular pathway by radiofrequency current using a bipolar epicardial-endocardial electrode configuration. Eur Heart J. 1988;9(8):927–932. PubMed

Bashir Y, Heald SC, O’Nunain S, Katritsis D, Camm AJ, Ward DE. Radiofrequency current delivery by way of a bipolar tricuspid annulus-mitral annulus electrode configuration for ablation of posteroseptal accessory pathways. J Am Coll Cardiol. 1993;22(2):550–556. doi: 10.1016/0735-1097(93)90063-7. PubMed DOI

Merino JL, Peinado R, Ramirez L, Echeverria I, Sobrino JA. Ablation of idiopathic ventricular tachycardia by bipolar radiofrequency current application between the left aortic sinus and the left ventricle. Europace. 2000;2(4):350–354. doi: 10.1053/eupc.2000.0121. PubMed DOI

Teh AW, Reddy VY, Koruth JS, Miller MA, Choudry S, D’Avila A, Dukkipati SR. Bipolar radiofrequency catheter ablation for refractory ventricular outflow tract arrhythmias. J Cardiovasc Electrophysiol. 2014;25(10):1093–1099. doi: 10.1111/jce.12460. PubMed DOI

Wong KC, Jones M, Qureshi N, Sadarmin PP, De Bono J, Rajappan K, Bashir Y, Betts TR. Balloon occlusion of the distal coronary sinus facilitates mitral isthmus ablation. Heart Rhythm. 2011;8(6):833–839. doi: 10.1016/j.hrthm.2011.01.042. PubMed DOI

Matsuo S, Yamane T, Date T, Hioki M, Narui R, Ito K, Tanigawa S, Nakane T, Yamashita S, Tokuda M, et al. Completion of mitral isthmus ablation using a steerable sheath: prospective randomized comparison with a nonsteerable sheath. J Cardiovasc Electrophysiol. 2011;22(12):1331–1338. doi: 10.1111/j.1540-8167.2011.02112.x. PubMed DOI

Baez-Escudero JL, Morales PF, Dave AS, Sasaridis CM, Kim YH, Okishige K, Valderrabano M. Ethanol infusion in the vein of Marshall facilitates mitral isthmus ablation. Heart Rhythm. 2012;9(8):1207–1215. doi: 10.1016/j.hrthm.2012.03.008. PubMed DOI PMC

Ohkubo K, Watanabe I, Okumura Y, Kofune M, Nagashima K, Sonoda K, Mano H, Nakai T, Kunimoto S, Kasamaki Y, et al. A novel technique for improved lesions in the coronary sinus. comparison of bipolar and unipolar ablation. Int Heart J. 2012;53(2):129–132. doi: 10.1536/ihj.53.129. PubMed DOI

Wong KC, Lim C, Sadarmin PP, Jones M, Qureshi N, De Bono J, Rajappan K, Bashir Y, Betts TR. High incidence of acute sub-clinical circumflex artery ‘injury’ following mitral isthmus ablation. Eur Heart J. 2011;32(15):1881–1890. doi: 10.1093/eurheartj/ehr117. PubMed DOI

Takahashi Y, Jais P, Hocini M, Sanders P, Rotter M, Rostock T, Sacher F, Jais C, Clementy J, Haissaguerre M. Acute occlusion of the left circumflex coronary artery during mitral isthmus linear ablation. J Cardiovasc Electrophysiol. 2005;16(10):1104–1107. doi: 10.1111/j.1540-8167.2005.50124.x. PubMed DOI

Wong KC, Qureshi N, Jones M, Rajappan K, Bashir Y, Betts TR. Mitral isthmus ablation using steerable sheath and high ablation power: a single center experience. J Cardiovasc Electrophysiol. 2012;23(11):1193–1200. doi: 10.1111/j.1540-8167.2012.02380.x. PubMed DOI

Chugh A, Makkar A, Yen Ho S, Yokokawa M, Sundaram B, Pelosi F, Jongnarangsin K, Oral H, Morady F. Manifestations of coronary arterial injury during catheter ablation of atrial fibrillation and related arrhythmias. Heart Rhythm. 2013;10(11):1638–1645. doi: 10.1016/j.hrthm.2013.09.001. PubMed DOI

Use of Bipolar Radiofrequency Catheter Ablation in the Treatment of Cardiac Arrhythmias