Effects of Hyperthyroidism on the Heart

Thyroid hormones have a significant cellular and hemodynamic effect, playing an important role on cardiac function and structure. On the basis of the understanding of the cellular mechanisms of action of thyroid hormones on the heart and cardiovascular system, we can explain the changes in cardiac output, cardiac contractility, arterial pressure, vascular resistance and rhythm disorders, that results from thyroid dysfunction. It is important to know cardiovascular complications in hyperthyroidism, because of their high frequency in clinical presentation and increased mortality and morbidity risk. The importance of the recognition of the effects of thyroid disorders on the heart, comes from various studies, where it is established that the restoration of normal thyroid function is accompanied by cardiovascular hemodynamic improvements. In the present review, we discuss how hyperthyroidism affects cardiovascular system.