title: Subclinical hypothyroidism and left ventricular mechanics: a three-dimensional speckle tracking study.
abstract: BACKGROUND
  Subclinical hypothyroidism (SHT) is associated with left ventricular (LV) remodeling. The LV mechanics has not been previously assessed by two- and three-dimensional (2DE and 3DE) speckle tracking imaging in the SHT patients.
  
  
  OBJECTIVE
  The objective of the study was to investigate LV mechanics by 2DE and 3DE speckle tracking in the SHT patients and evaluate the influence of levothyroxine therapy on LV remodeling.
  
  
  METHODS
  We conducted a prospective study. All SHT patients received levothyroxine therapy and were followed up for 1 year after the euthyroid state had been achieved.
  
  
  METHODS
  The study was performed at a university hospital.
  
  
  METHODS
  We included 54 untreated women with SHT and 40 healthy control women who were of similar age.
  
  
  METHODS
  The 2DE strain and strain rates, 3DE volumes, 3DE strain, and thyroid hormones levels were assessed.
  
  
  RESULTS
  The 2DE LV longitudinal and circumferential strain and systolic and early diastolic strain rates were significantly decreased in the SHT patients before therapy in comparison with the controls or the SHT patients after therapy. The 3DE LV cardiac output and ejection fraction were significantly reduced in the SHT patients at baseline compared with the controls or patients after 1 year of treatment. The 3DE LV longitudinal and radial strains were significantly lower in the SHT group before treatment in comparison with the controls or patients after therapy, whereas the 3DE LV circumferential and area strains gradually increased from untreated SHT patients, among the treated SHT patients, to the controls.
  
  
  CONCLUSIONS
  SHT significantly affects LV deformation assessed by 2DE and 3DE speckle tracking. The improvement of LV mechanics after 1 year of levothyroxine treatment is significant but incomplete.
authors.affiliation: Departments of Cardiology (M.T., V.C.) and Endocrinology (S.I., N.K., Z.C.), University Clinical Hospital Center "Dr Dragisa Misovic," Heroja Milana Tepica 1, and Faculty of Medicine (N.K., Z.C., V.C.), Doktora Subotica 6, 11000 Belgrade, Serbia.
authors.forename: Marijana
authors.initials: M
authors.lastname: Tadic
authors.forename: Sanja
authors.initials: S
authors.lastname: Ilic
authors.forename: Nada
authors.initials: N
authors.lastname: Kostic
authors.forename: Zorica
authors.initials: Z
authors.lastname: Caparevic
authors.forename: Vera
authors.initials: V
authors.lastname: Celic
mesh_terms: D000328:Adult; D058070:Asymptomatic Diseases; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D019560:Echocardiography, Three-Dimensional / Q000379:methods; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D007037:Hypothyroidism / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology*; D008875:Middle Aged; D013318:Stroke Volume / Q000502:physiology; D013960:Thyroid Function Tests; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000453:epidemiology; D016277:Ventricular Function, Left