Justification of Increasing the Blood Flow Velocity in the Arteries of the Thyroid Gland in Autoimmune Thyroiditis as a Reflection of Endothelial Changes Due to Inflammatory Status

Objective: The aim of the research was to determine the dependence of the blood flow velocity in the thyroid arteries in patients with Autoimmune Thyroiditis (AIT) on the presence of atherosclerotic carotid disease and the level of systemic blood pressure. Methods: The research involved 20 patients with AIT in euthyroid state, 30 patients AIT in euthyroid state with stable Coronary Heart Disease (CHD), 30 patients with stable CHD and 30 healthy individuals. Participants of the research were examined using ultrasound of carotid arteries and inferior thyroid arteries. Parameters of blood flow velocity were compared with the level of systemic blood pressure. Results: In AIT peak systolic velocity and resistance index in the inferior thyroid arteries were significantly higher than in healthy individuals and patients with CHD (p<0.05). In patients with CHD velocity parameters in carotid arteries were high, unlike in the healthy individuals and patients with AIT (p<0.05). In patients with AIT without CHD the atherosclerotic changes of carotid arteries were not found. Increased systemic blood pressure was noticed in all patients with CHD without significant differences between groups. Conclusion: The value of peak systolic velocity and resistance index of inferior thyroid arteries in autoimmune thyroiditis are noticed even with euthyroidism and do not depend on systemic blood pressure and atherosclerosis of carotid arteries. Increasing the thyroid arterial blood flow velocity parameters should be considered as sign of an active inflammatory period AIT, where advanced fibrosis is not present.