Hyperthyroidism can cause patients to have a rapid heartbeat. Hyperthyroidism, known as hyperthyroidism, is an autoimmune abnormality or other factors that increase the secretion of total thyroxine T4 and T3 synthesis in the body, resulting in an increase in the body’s metabolic rate and increased sympathetic excitability, which is manifested in the cardiovascular system as a rapid heartbeat. In addition, patients with hyperthyroidism may also develop adverse conditions such as hyperthyroid heart disease and heart failure. If left untreated, hyperthyroidism can lead to damage to the cardiovascular system, and a prolonged untreated rapid heartbeat can easily induce atrial fibrillation, leading to thrombosis. Blood clots that travel and embolize to the pulmonary arteries can lead to sudden pulmonary embolism or even death. A rapid heartbeat is the body’s warning to hyperthyroidism patients, who should actively control their condition. Usually patients with hyperthyroidism can be treated with oral anti-thyroid medications or surgery. For rapid heartbeat, the drug propranolol, which inhibits sympathetic excitation, can be used to help control the rapid heartbeat. In the case of severe arrhythmias, systematic treatment under the supervision of a cardiovascular physician is required.