Effect of Thyroid Dysfunction on Left Ventricular Performance Using Different Echo-Doppler Modalities

Background Thyroid dysfunction (Thy.D) is one of the commonest endocrinological disorders that increase cardiovascular morbidity and mortality. Echocardiography is a useful, noninvasive, easily accessible, and affordable tool for detection of early cardiovascular changes in patients with thyroid disorders. Aim To assess the effect of Thy.D on left ventricular (LV) performance using different echo-Doppler modalities. Patients and methods This study included 60 individuals, divided into three groups: GI: 20 patients (hypothyroidism), GII: 20 patients (hyperthyroidism), and 20 healthy individuals as controls (GIII). All participants underwent history taking, clinical examination, thyroid profile (free triiodothyronine, free tetraiodothyronine, and thyroid-stimulating hormone), conventional echocardiography, tissue Doppler imaging (TDI) velocities averaged from four annular sites (Av-Sa, Av-Ea, and Av-Aa), TDI-derived strain, and two-dimensional-global longitudinal strain (2D-GLS). Results Despite LV systolic function being preserved in all studied groups, there was a statistically significant reduction in GI and GII compared with GIII (CL), with more reduction in GI (P<0.05). There was a significantly higher Tei-index in patients with Thy.D (P<0.05) by conventional Doppler, with more increase in GI by TDI (P=0.0001). There is a significant lower TDI-strain parameters in both patient groups compared with CL (P<0.01), and regarding 2D-GLS of the LV, there was significant lower LV-GLS in GI and GII, with more significant reduction in GI (P<0.01 and <0.05 respectively). There was a significant increase in E/Ea in both patient groups in comparison with CL, with more increase in GI (P=0.0003 in GI and 0.01 in GII). Conclusion Thyroid disorders have a significant effect on LV systolic and diastolic functions. TDI (velocities and strain) and 2D-GLS are useful indices for detection of LV functions in patients with Thy.D.