title: Predictors of electrical storm in patients with idiopathic dilated cardiomyopathy--how to stratify the risk of electrical storm.
abstract: BACKGROUND
  Electrical storm (ES) is a serious problem in patients with an implantable cardioverter defibrillator (ICD). However, insufficient reports have indicated the predictors of ES in ICD patients with idiopathic dilated cardiomyopathy (DCM). The purpose of this study was to clarify the predictors of ES for risk stratification in DCM patients with an ICD.
  
  
  RESULTS
  Of 446 ICD patients, 53 DCM patients were included in this study. During a mean follow-up of 55+/-36 months, ES (> or =3 times appropriate ICD therapy within 24 h) occurred in 18/53 (34%) patients. According to multivariate Cox proportional hazard regression analysis, a duration of the terminal low amplitude signals of <40 microV (LAS40) (HR 1.4/10 ms increase, 95% confidence interval (CI) 1.1-2.1; P=0.0049) or root mean square voltage of the last 40 ms of the QRS complex (RMS40) (HR 0.88/1 microV, 95%CI 0.77-0.96; P=0.001) on the signal averaged electrocardiogram, and a history of atrial fibrillation (AF) before ICD implantation (HR 2.3, 95%CI 1.2-5.0; P=0.013) were independently associated with an increased risk of ES.
  
  
  CONCLUSIONS
  Our data indicated that a longer LAS40, lower RMS40 and history of AF before ICD implantation could strongly predict ES, and the combination of those parameters could effectively stratify the risk of ES in DCM patients.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, National Cardiovascular Center, Suita, Japan.
authors.forename: Masateru
authors.initials: M
authors.lastname: Takigawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Noda
authors.forename: Takashi
authors.initials: T
authors.lastname: Kurita
authors.forename: Naohiko
authors.initials: N
authors.lastname: Aihara
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yamada
authors.forename: Hideo
authors.initials: H
authors.lastname: Okamura
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Satomi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Suyama
authors.forename: Wataru
authors.initials: W
authors.lastname: Shimizu
authors.forename: Shiro
authors.initials: S
authors.lastname: Kamakura
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000628:therapy; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D018570:Risk Assessment