title: Evaluation of atrial electromechanical delay and diastolic functions in patients with hyperthyroidism.
abstract: OBJECTIVE
  Hyperthyroidism is a well-known cause of atrial fibrillation (AF) which is associated with increased morbidity and mortality. Atrial electromechanical delay (EMD) is a significant predictor of AF. The aim of this study was to assess the atrial EMD and diastolic functions in subclinical and overt hyperthyroidism by using tissue Doppler imaging (TDI).
  
  
  RESULTS
  The study population consisted of 3 groups: group I (30 healthy subjects), group II (38 patients with subclinical hyperthyroidism), and group III (25 patients with overt hyperthyroidism). Atrial electromechanical coupling was measured with TDI. Standard echocardiographic measurements and parameters of diastolic function were obtained by conventional echocardiography and TDI. Intra- and inter-atrial EMD were significantly prolonged in subclinical and overt hyperthyroidism compared with control group (P = 0.03 and P < 0.001 for intra-atrial EMD; P < 0.001 for inter-atrial EMD). In groups II and III, mitral A velocity (P = 0.005 and P = 0.001) and mitral E-wave deceleration time (P < 0.001 and P = 0.02) were significantly increased, and mitral E/A ratio (P = 0.005 and P = 0.001) was significantly decreased compared with the control group. The lateral mitral Em /Am ratio in group II and group III was significantly lower than controls (P = 0.001). Mitral Em /Am ratio (β = -0.32, P = 0.002) and thyroid stimulating hormone (TSH) level (β = -0.27, P = 0.009) were negatively and independently correlated with inter-atrial EMD.
  
  
  CONCLUSIONS
  This study showed that intra- and inter-atrial electromechanical intervals were prolonged and diastolic function was impaired in both overt and subclinical hyperthyroidism. TSH level and mitral Em /Am ratio were found as independent predictors of atrial EMD.
authors.affiliation: Department of Cardiology, Faculty of Medicine, Kahramanmaras Sutcu Imam University, Kahramanmaras, Turkey.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Sokmen
authors.forename: Gurkan
authors.initials: G
authors.lastname: Acar
authors.forename: Gulizar
authors.initials: G
authors.lastname: Sokmen
authors.forename: Ahmet
authors.initials: A
authors.lastname: Akcay
authors.forename: Murat
authors.initials: M
authors.lastname: Akkoyun
authors.forename: Sedat
authors.initials: S
authors.lastname: Koroglu
authors.forename: Alper Bugra
authors.initials: AB
authors.lastname: Nacar
authors.forename: Mesut
authors.initials: M
authors.lastname: Ozkaya
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000209:etiology; D003971:Diastole; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications*; D008297:Male
keywords: atrial electromechanical delay; hyperthyroidism; tissue Doppler imaging