title: Relationship between left ventricular mass and heart sympathetic activity in male obese subjects.
abstract: BACKGROUND
  Pathogenesis of left ventricular hypertrophy (LVH) is multifactorial, but evidence that the sympathetic system is involved in progression of cardiovascular structural alterations in hypertension is substantial. However, the relationship between heart sympathetic activity and left ventricular mass in normotensive obese subjects has not been studied.
  
  
  METHODS
  We studied 103 male normotensive subjects (53 obese and 50 non-obese). Left ventricular mass (LVM), heart sympathetic activity by 60 min electrocardiograph (EKG) monitoring, leptin, insulin, lipid profile, and blood pressure were measured.
  
  
  RESULTS
  Obese subjects showed higher LVM (p=0.0002), low frequency/high frequency ratio (LF/HF) (p=0.004), systolic and diastolic blood pressure (p <0.00001 for both), insulin (p=0.00001), and leptin levels (p <0.00001) than non-obese subjects. In contrast, standard deviation (SD) of all rate-rhythm (R-R) intervals (SDNN) (p=0.0002) and total power (TP) (p=0.03) were lower in obese than in non-obese subjects. In multiple regression analysis for factors associated with LVM, body mass index (BMI) (R=0.24), systolic blood pressure (R=0.22), and LF/HF (R=0.21) were the only factors included in the model (R2=0.32, p <0.0001).
  
  
  CONCLUSIONS
  LVM is increased in normotensive obese subjects and correlates with systolic blood pressure and heart sympathetic activity.
authors.affiliation: Unidad de Investigación en Epidemiología Clínica, Instituto Mexicano del Seguro Social, Delegación Guanajuato, León, Guanajuato, Mexico.
authors.forename: Norma
authors.initials: N
authors.lastname: Amador
authors.forename: José
authors.initials: J
authors.lastname: de Jesús Encarnación
authors.forename: Leticia
authors.initials: L
authors.lastname: Rodríguez
authors.forename: Adolfo
authors.initials: A
authors.lastname: Tello
authors.forename: Manuel
authors.initials: M
authors.lastname: López
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: Guízar
mesh_terms: D000328:Adult; D001794:Blood Pressure; D004452:Echocardiography; D004562:Electrocardiography; D006321:Heart / Q000294:innervation*; D006801:Humans; D017379:Hypertrophy, Left Ventricular; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D009765:Obesity / Q000473:pathology* / Q000503:physiopathology*; D013223:Statistics as Topic; D013564:Sympathetic Nervous System / Q000502:physiology*