title: A randomized study on the efficacy of intravenous cibenzoline and pilsicainide administered prior to electrical cardioversion in patients with lone paroxysmal and persistent atrial fibrillation.
abstract: RESULTS
  This study included 68 patients (47 men, 21 women, mean age 69 years) in whom atrial fibrillation (AF) recurred immediately after electrical cardioversion (EC) was performed with no antiarrhythmic drugs. After administration of cibenzoline (Cib, 70 mg) or pilsicainide (Pil, 50 mg) on a randomized basis, all patients again underwent EC at the same energy as that prior to administration of antiarrhythmic drugs. We compared the efficacy of Cib (n = 35) and Pil (n = 33), and examined factors affecting successful cardioversion in patients treated with Cib. These patients were divided into a successful group (Group A) and an unsuccessful group (Group B). The success rate of EC at the same energy after intravenous Cib administration (77%) was significantly greater than that after intravenous Pil administration (42%) (p < 0.01). In patients treated with Cib, AF duration was significantly greater in Group B (55.8 ± 48.2 h) than in Group A (29.1 ± 17.0 h) (p < 0.05). Plasma concentrations of atrial natriuretic peptide (ANP) during AF and the ratio of ANP level during AF to that during sinus rhythm were also significantly greater in Group A (110.9 ± 69.7 pg/ml and 3.9 ± 2.8, respectively) than in Group B (58.2 ± 36.1 pg/ml and 1.8 ± 0.9, respectively) (both, p < 0.05). In patients treated with Pil, AF duration was also significantly greater in Group B (59.7 ± 44.6h) than in Group A (19.6 ± 21.7 h) (p < 0.05), and the ratio of ANP level during AF to that during sinus rhythm was significantly greater in Group A (3.5 ± 2.6) than in Group B (1.7 ± 0.9) (p < 0.05).
  
  
  CONCLUSIONS
  In patients with AF previously refractory to conventional EC, intravenous Cib administration was more effective in restoring sinus rhythm with EC than intravenous Pil administration. The capacity of ANP secretion during AF tachycardia may be a predictive indicator for the prevention of AF recurrence in electrically remodeled atria.
authors.affiliation: Division of Cardiology, Department of Internal Medicine and Memorial Heart Center, Iwate Medical University School of Medicine, Morioka, Japan. sym.koma@imu.ncvc.go.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Komatsu
authors.forename: Hideaki
authors.initials: H
authors.lastname: Tachibana
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sato
authors.forename: Mahito
authors.initials: M
authors.lastname: Ozawa
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ohshima
authors.forename: Makoto
authors.initials: M
authors.lastname: Orii
authors.forename: Fusanori
authors.initials: F
authors.lastname: Kunigida
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage*; D001281:Atrial Fibrillation / Q000628:therapy*; D009320:Atrial Natriuretic Factor / Q000097:blood; D004554:Electric Countershock; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage*; D007275:Injections, Intravenous; D008012:Lidocaine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008297:Male
chemical_list: D000889:Anti-Arrhythmia Agents; D007093:Imidazoles; D009320:Atrial Natriuretic Factor; D008012:Lidocaine; C042288:pilsicainide; C032151:cifenline