title: Impact of chronic use of cibenzoline on left ventricular pressure gradient and left ventricular remodeling in patients with hypertrophic obstructive cardiomyopathy.
abstract: BACKGROUND
  Cibenzoline, a class Ia antiarrhythmic drug, is useful for reducing the left ventricular pressure gradient (LVPG) in patients with hypertrophic obstructive cardiomyopathy (HOCM). However, chronic effects of cibenzoline on LVPG and left ventricular (LV) remodeling are unknown.
  
  
  METHODS
  Forty-one patients with HOCM participated in this study. Echocardiographic, electrocardiographic, and brain natriuretic peptide (BNP) data collected before and after cibenzoline treatment were compared. From the relation between LVPG and plasma concentration of cibenzoline, an efficacious plasma concentration of cibenzoline was estimated.
  
  
  RESULTS
  The mean follow-up period was 74.2±47.1 months. The LVPG decreased from 104.8±62.6mmHg to 27.6±30.5mmHg (p<0.0001). The LV end-diastolic dimension increased from 42.8±5.8mm to 46.2±5.4mm (p<0.0001), but neither LV end-systolic dimension nor LV fractional shortening changed significantly. The left atrial dimension decreased from 40.0±4.7mm to 36.2±5.1mm (p<0.0001). The E-wave velocity/A-wave velocity ratio increased, early diastolic annular velocity (Ea) increased, and E/Ea ratio decreased. The interventricular septal wall thickness, LV posterior wall thickness, the Sokolow-Lyon index, and the depth of negative T wave decreased. The heart rate-corrected QT interval was shortened. Plasma BNP level decreased from 418.8±423.7pg/ml to 213.7±154.1pg/ml (p<0.02). The safe and efficacious plasma concentration of cibenzoline was between 300ng/mL and 1500ng/mL.
  
  
  CONCLUSIONS
  Long-term treatment with cibenzoline attenuated LVPG, improved LV diastolic dysfunction, and induced LV hypertrophy regression in patients with HOCM without causing serious complications.
authors.affiliation: Division of Cardiology, Uwajima City Hospital, Uwajima, Ehime, Japan. Electronic address: mhamada@uwajima-mh.jp.
authors.forename: Mareomi
authors.initials: M
authors.lastname: Hamada
authors.affiliation: Division of Cardiology, Uwajima City Hospital, Uwajima, Ehime, Japan.
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Ikeda
authors.affiliation: Division of Cardiology, Uwajima City Hospital, Uwajima, Ehime, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Ohshima
authors.affiliation: Division of Cardiology, Uwajima City Hospital, Uwajima, Ehime, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Division of Physiological Laboratory, Uwajima City Hospital, Uwajima, Ehime, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Kubota
authors.affiliation: Division of Cardiology, Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Toon-city, Ehime, Japan.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Ogimoto
authors.affiliation: Clinical Nursing, Ehime University Graduate School of Medicine, Toon-city, Ehime, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Shigematsu
mesh_terms: D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects*; D002312:Cardiomyopathy, Hypertrophic / Q000188:drug therapy* / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000188:drug therapy / Q000209:etiology; D007093:Imidazoles / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000032:analysis; D013995:Time; D016277:Ventricular Function, Left / Q000187:drug effects; D017725:Ventricular Pressure / Q000187:drug effects*; D020257:Ventricular Remodeling / Q000187:drug effects*
chemical_list: D000889:Anti-Arrhythmia Agents; D007093:Imidazoles; D020097:Natriuretic Peptide, Brain; C032151:cifenline
keywords: Antiarrhythmic agent; Hypertrophic cardiomyopathy; Left ventricular diastolic function; Left ventricular hypertrophy; Left ventricular pressure gradient