Advances in the Study of Thyroid Hormones and Atrial Fibrillation

Abstract

Atrial fibrillation (AF) is a common cardiac arrhythmia characterized by irregular, rapid and ineffective contractions of the atrial rhythm. The relationship between thyroid hormones and AF has been of interest because past studies have identified that thyroid hormones play an important role in the cardiovascular system and that there is a strong link between abnormal thyroid function and AF. Hyperthyroidism is often accompanied by symptoms of arrhythmia such as increased heart rate and arrhythmia, whereas hypothyroidism patients may exhibit abnormalities such as slowed heart rate and enlarged atria. Thyroid hormones are involved in the onset and development of AF through several pathways. First, thyroid hormone may affect the electrophysiological properties of cardiomyocytes, altering the excitability and repolarization process of atrial cells. Second, thyroid hormones may also affect the structure and function of the atria, leading to atrial enlargement and fibrosis, thereby increasing susceptibility to AF. In addition, thyroid hormones may alter the maintenance and regression of AF by affecting the autonomic regulation of the cardiovascular system. This suggests that thyroid hormones play a key role in the pathophysiologic mechanisms of AF. In recent years, an increasing number of studies have focused on the relationship between thyroid hormones and AF and have attempted to reveal their specific mechanisms of action. Some studies have suggested that modulation of thyroid function may be a new strategy for the treatment of atrial fibrillation. In this article, we present a review of the latest research progress on thyroid hormones and atrial fibrillation.