Objective: Studies investigating systolic and diastolic left ventricle function in subclinical hypothyroidism (ScH) have shown controversial results. As myocardium is a target organ of thyroid hormone action, the aim of the study was to assess the left ventricular systolic and diastolic function in ScH.
Methods: Fifty-four patients with newly diagnosed ScH and 30 euthyroid controls, patients of the University Clinic of the Endocrinology, Diabetes, and Metabolic Disorders Clinic were enrolled. Transthoracic echocardiography, using M-mode, two-dimensional (2D), pulsed, continuous and color-Doppler, and advanced echocardiographic modalities Tissue Doppler and two-dimensional speckle tracking was performed in all subjects.
Results: Although normal echocardiographic values of all measured parameters, SCH patients were significantly different from their matched controls: the ratio between E/A was statistically significantly lower (1,26±0,36 vs. 1,03±0,29, p<0,01), the ratio between Е/е’ sep. was statistically significantly higher (6,04±1,64 vs. 7,62±2,29, p<0,01), MPI was statistically significantly higher (0,43±0,07 vs. 0,47±0,08, p<0,05), GLS had statistically significantly lower negative value (-20,9±1,7 vs. -19,55±2,3%, p<0,001), and S/TDI was statistically significantly lower (0,092±0,011 vs. 0,077±0,013, p<0,01). TSH negatively correlated with EF (r=-0,15, p<0,05), E/A(r=-0,14, p<0,05), GLS (r=-0,26, p<0,001), S/TDI (r=-0,22, p<0,01), and positively correlated with E/e 'sep. (r=0,14, p<0,05).
Conclusion: Subclinical hypothyroidism contributes to changes in certain parameters involved in the assessment of global and longitudinal systolic and diastolic left ventricular function compared to healthy individuals.
