Endocrine Abstracts

Introduction: The objective of this study was to investigate left atrial mechanical function (LAMF) and to associate these measurements with diastolic function in subclinical (SHT) and overt hypothyroidism (OHT).

Methods: Twenty-six newly diagnosed patients with SHT (20F, 6M, mean age 42.2±12.5 years), 21 patients with OHT (17F, mean age 40.2±8.5 years) and 28 healthy volunteers (control group, 21F, 42.4±11.2 years) were enrolled in this study. Standart M-mode measurements, mitral Doppler flow analysis, tissue Doppler parameters at lateral, septal and right ventricular annulus. Diastolic functions with both conventional and tissue Doppler method were measured. Left atrial maximal volume, minimal volume and volume at atrial systole measured using the disc method. Parameters reflecting left atrial mechanical function were measured.

Results: Active emtptying volume (AEV) and active emptying fraction (AEF) were found to be significantly increased in the OHT and SHT group compared to controls. Passive emptying volume and passive emptying fraction were lower in the OHT and SHT group compared to controls but did not reach statistically significance. Conduit volume was significantly lower in the OHT and SHT group compared to controls. The E/A ratio were significantly lower in the SHT and OHT groups compared to the controls. The lateral and septal E/Em were significantly higher, septal Em/Am was significantly lower in the OHT and SHT group compared to the controls. A correlation analysis revealed that the E/A ratio was negatively correlated with LAAEV and LAAEF (r=−0.28; P=0.02, r=−0.29; P=0.012 respectively). The E/Em ratio measured at the septal annulus was positively correlated with AEV and AEF (r=0.24; P=0.04, r=34; P=0.003 respectively). There was a negative correlation between the septal Em/Am ratio and AEF (r=−0.26; P=0.03).

Conclusion: LAMF are impaired in patients with thyroid dysfunction. We consider that impairment of LAMF is primarily caused by seconder to impairment of left ventricular diastolic functions.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.