A circumferential ablation device assembly which is adapted to forming a circumferential conduction block in a pulmonary vein is described. The assembly includes a circumferential oblation clement which is adapted to ablate a circumferential region of tissue along a pulmonary vein wall which circumscribes...http://www.google.fr/patents/US7993337?utm_source=gb-gplus-shareBrevet US7993337 - Circumferential ablation device assembly