Objective:To retrospectively summarize the clinical characteristics and treatment of 49 patients with hyperthyroid cardiopath and to explore the diagnosis and treatment methods of hyperthyroid cardiopathy.Methods:A total of 49 patients with hyperthyroid cardiopath(HC group) who were successfully treated and followed up in the Department of Endocrinology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, from January 2016 to December 2021 were collected, and 85 cases of Graves′ disease without heart disease were collected as the control group(GD group). The medical history, laboratory tests, and echocardiographic parameters of the two groups were compared. Differences in thyroid and cardiac indicators before and after treatment in the HC group were summarized, along with the dosage of β-receptor blockers used in treating different types of conditions(atrial fibrillation and heart failure.Results:Patients in the HC group were older and had a longer duration of hyperthyroidism than those in the GD group( P<0.001, P=0.002). There were no significant differences in thyroid hormone levels between the two groups except for reverse triiodothyronine(rT 3). Age and rT 3 were independent risk factors of hyperthyroid cardiopathy. rT 3 level was linearly positively correlated with brain natriuretic peptide, systolic pulmonary artery pressure, left artrium diamete (LAD) and left ventricular end-systolic diameter(LVDs; r=0.352, P<0.001; r=0.392, P=0.019; r=0.202, P=0.029; r=0.242, P=0.028). In patients of HC group, free triiodothyronine(FT 3) level returned to normal range after 2.87(1.63, 5.53) months of treatment with radioiodine(41/49) or antithyroid drugs(8/49), while brain natriuretic peptide, LAD, LVDs, and systolic pulmonary artery pressure declined after 5.00(1.25, 8.00) months of treatment. Non-selective β-receptor blockers were used for both hyperthyroid heart failure and atrial fibrillation, and there was no statistically significant difference in dosage[(86.52±47.83)mg vs(88.67±47.19)mg, P>0.05]. Conclusions:rT 3 may be a biomarker of hyperthyroid cardiopath and indicate the severity of hyperthyroidism. β-receptor blockers are crucial in treating patients with hyperthyroidism who develop atrial fibrillation and heart failure.