Bipolar radiofrequency catheter ablation for refractory perimitral flutter: a case report.
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.


METHODS
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.


CONCLUSIONS
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 (IKEM), Vídeňská 1958/9, Prague, 140 21, Czech Republic. look.tsuuhan@gmail.com.
Kenichiro
K
Yamagata
Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague, 140 21, Czech Republic. dawi@ikem.cz.
Dan
D
Wichterle
Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague, 140 21, Czech Republic. pepi@ikem.cz.
Petr
P
Peichl
Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague, 140 21, Czech Republic. baal@ikem.cz.
Bashar
B
Aldhoon
Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague, 140 21, Czech Republic. roci@ikem.cz.
Robert
R
Čihák
Department of Cardiology, Institute for Clinical and Experimental Medicine (IKEM), Vídeňská 1958/9, Prague, 140 21, Czech Republic. joka@ikem.cz.
Josef
J
Kautzner
D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D012008:Recurrence; D016896:Treatment Outcome