RESUMO
Purpose To assess the left ventricular global systolic function changes using three-dimensional speckle tracking imaging (3D-STI) in female patients with subclinical hypothyroidism (SHT) undergoing L-thyroxine treatment. Materials and Methods Thirty-eight female patients with SHT and 40 healthy female volunteers of the same age (control group) were selected, all the SHT patients received L-thyroxine therapy and were followed for 1 year after euthyroid status was achieved; all the participants underwent blood biochemical examinations, complete conventional echocardiographic and 3D-STI examinations, left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVEDs), interventricular septal depth (IVSd), left ventricular posterior wall depth (LVPWd), left atrial diameter (LAD), diastolic mitral flow spectrum of A peak, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular ejection fraction (LVEF) of the two groups were compared, and the correlation of parameters of three dimensional left ventricular global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), global area strain (GAS), and thyroid stimulating hormone (TSH) with each parameter was analyzed. Results IVSd and LVPWd in the study group were higher than those of the control group (t=3.30 and 3.64, P<0.05). Compared with the control group, GLS, GCS, GRS and GAS of left ventricular of SHT patients in the study group were significantly lower (t=8.60, 11.95, 9.78 and 5.92, P<0.05) before treatment. GLS, GCS, GRS and GAS of SHT patients improved after L-thyroxine therapy, and the difference was statistically significant (t=6.91, 9.41, 6.46 and 4.31, P<0.05).TSH level was negatively correlated with E/A ratio and E (r= - 0.39 and - 0.42, P<0.05), and also negatively correlated with GLS, GCS, GRS and GAS (r= - 0.38, - 0.56, - 0.33 and - 0.41, P<0.05). Conclusion Left ventricular global systolic function changes of SHT patients before and after L-thyroxine treatment can be evaluated properly using 3D-STI.