Heart problems caused by hyperthyroidism mainly include the following. First, in the early stages of hyperthyroidism, patients may experience palpitations, tachycardia, panic attacks and hand tremors, which are associated with elevated levels of thyroid hormones in the blood and excitation of heart muscle cells. Therefore, in the early stage of hyperthyroidism, the patient will have obvious arrhythmia, with sinus tachycardia being the most common. Second, a long history of hyperthyroidism can make arrhythmias that have already occurred irreversible, such as prolonged sinus tachycardia, which may progress to atrial fibrillation, and some atrial fibrillation is permanently irreversible. Complications associated with atrial fibrillation can occur next. And then perennial hyperthyroidism can lead to impairment of cardiac function, or heart failure.