Referenced in: none

Automatically associated channels: Kir2.1

Title: Efficacy and safety of flecainide for ventricular arrhythmias in patients with Andersen-Tawil syndrome with KCNJ2 mutations.

Authors: Koji Miyamoto, Takeshi Aiba, Hiromi Kimura, Hideki Hayashi, Seiko Ohno, Chie Yasuoka, Yoshihito Tanioka, Takeshi Tsuchiya, Yoko Yoshida, Hiroshi Hayashi, Ippei Tsuboi, Ikutaro Nakajima, Kohei Ishibashi, Hideo Okamura, Takashi Noda, Masaharu Ishihara, Toshihisa Anzai, Satoshi Yasuda, Yoshihiro Miyamoto, Shiro Kamakura, Kengo Kusano, Hisao Ogawa, Minoru Horie, Wataru Shimizu

Journal, date & volume: Heart Rhythm, 2015 Mar , 12, 596-603

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/25496985

Abstract
Andersen-Tawil syndrome (ATS) is an autosomal dominant genetic or sporadic disorder characterized by ventricular arrhythmias (VAs), periodic paralyses, and dysmorphic features. The optimal pharmacological treatment of VAs in patients with ATS remains unknown.We evaluated the efficacy and safety of flecainide for VAs in patients with ATS with KCNJ2 mutations.Ten ATS probands (7 females; mean age 27 ± 11 years) were enrolled from 6 institutions. All of them had bidirectional VAs in spite of treatment with β-blockers (n = 6), but none of them had either aborted cardiac arrest or family history of sudden cardiac death. Twenty-four-hour Holter recording and treadmill exercise test (TMT) were performed before (baseline) and after oral flecainide therapy (150 ± 46 mg/d).Twenty-four-hour Holter recordings demonstrated that oral flecainide treatment significantly reduced the total number of VAs (from 38,407 ± 19,956 to 11,196 ± 14,773 per day; P = .003) and the number of the longest ventricular salvos (23 ± 19 to 5 ± 5; P = .01). At baseline, TMT induced nonsustained ventricular tachycardia (n = 7) or couplets of premature ventricular complex (n = 2); treatment with flecainide completely (n = 7) or partially (n = 2) suppressed these exercise-induced VAs (P = .008). In contrast, the QRS duration, QT interval, and U-wave amplitude of the electrocardiogram were not altered by flecainide therapy. During a mean follow-up of 23 ± 11 months, no patients developed syncope or cardiac arrest after oral flecainide treatment.This multicenter study suggests that oral flecainide therapy is an effective and safe means of suppressing VAs in patients with ATS with KCNJ2 mutations, though the U-wave amplitude remained unchanged by flecainide.