title: Complete right bundle branch block and QRS-T discordance can be the initial clue to detect S-ICD ineligibility.
abstract: BACKGROUND
  In order to minimize inappropriate shocks of subcutaneous implantable cardioverter-defibrillators (S-ICD), it is important to recognize who is suitable for S-ICD indication. This study aimed to clarify what types of cardiac disease are likely to fulfill the S-ICD screening criteria and ineligible factors for S-ICD in the standard 12-lead electrocardiogram (ECG).
  
  
  METHODS
  A total of 348 patients with heart disease were enrolled. They were assessed by supine and standing ECG recording to simulate the 3 S-ICD sensing vectors and standard 12-lead ECG, simultaneously. Clinical and ECG characteristics were analyzed to compare the patients who are eligible and ineligible with S-ICD screening ECG indication.
  
  
  RESULTS
  The mean age of study patients was 49±21 years and 244 (70%) were men. Nineteen percent of patients were unsuitable for S-ICD. There was no significant difference in ineligibility for S-ICD among cardiac diseases (p=0.48). Univariate analysis showed complete right bundle branch block (CRBBB), QRS-T discordance in lead II, and QRS-T discordance in 3 leads (I, II, and aVF) were more frequent in patients who were ineligible for S-ICD than in the eligible group. Multivariate regression analysis showed CRBBB and QRS-T discordance in 3 leads were independent predictors for ineligibility of S-ICD.
  
  
  CONCLUSIONS
  There are no differences in eligibility of S-ICD among types of cardiac diseases. CRBBB and QRS-T discordance were independent predictors for ineligibility.
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. Electronic address: motomitachibana@yahoo.co.jp.
authors.forename: Motomi
authors.initials: M
authors.lastname: Tachibana
authors.affiliation: Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nishii
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Morimoto
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kawada
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Miyoshi
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Sugiyama
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Nakagawa
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Watanabe
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Morita
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
mesh_terms: D000328:Adult; D000368:Aged; D017147:Defibrillators, Implantable / Q000009:adverse effects; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors
keywords: Implantable cardioverter-defibrillator; Sudden cardiac death; Ventricular arrhythmia