title: Implications of World Health Organization classification for body mass index on the correlations between common electrocardiographic indexes for left ventricular hypertrophy and left ventricular mass.
abstract: BACKGROUND
  Some electrocardiographic indexes such as Cornell index, Cornell product index, or Sokolow-Lyon index remain to be used in the clinical setting. We assessed the effects of body mass index (BMI) on the correlations between these ECG indexes and left ventricular mass (LVM).
  
  
  METHODS
  One hundred ninety-six outpatients who underwent both ECG and echocardiography on the same day were included in this study. In accordance with the World Health Organization (WHO) classification of BMI, the patients were classified into the four groups: underweight (<18.5 kg/m2, n = 30), normal weight (18.5-24.9 kg/m2, n = 83), overweight (25-29.9 kg/m2, n = 43), and obese (≥30 kg/m2, n = 40).
  
  
  RESULTS
  With increasing WHO classification of BMI, Cornell index (RaVL+SV3), Cornell product index [(RaVL+SV3)RQRS duration], and LVM increased. On the other hand, Sokolow-Lyon index (SV1+RV5) decreased. Cornell index correlated with LVM in normal weight group (r = 0.27, p = 0.015), but did not in the other groups. Cornell product index also correlated with LVM in normal weight group (r = 0.30, p = 0.006), but did not in the other groups. Sokolow-Lyon index correlated with LVM well in normal weight group (r = 0.32, p = 0.004) and better in underweight group (r = 0.61, p = 0.0004). However, no correlations were found in overweight and obese groups.
  
  
  CONCLUSIONS
  Our results suggest that BMI influences the correlations between these ECG indexes and LVM, and should be taken into consideration when assessing LVH.
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kurisu
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ikenaga
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Watanabe
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Tadanao
authors.initials: T
authors.lastname: Higaki
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimonaga
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Ishibashi
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Dohi
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Fukuda
authors.affiliation: a Department of Cardiovascular Medicine , Hiroshima University Graduate School of Biomedical and Health Sciences , Hiroshima , Japan.
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Kihara
mesh_terms: D000368:Aged; D015992:Body Mass Index; D004452:Echocardiography / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D014944:World Health Organization
keywords: Electrocardiogram; obesity; ventricular hypertrophy