Objective To analyze the activity of renin angiotensin system and its correlation with atrial fibrillation(AF) in patients with coronary heart disease and hyperthyroidism. Methods From April 2020 to July 2022, 75 patients with coronary heart disease admitted to the Shanxi Provincial Cardiovascular Hospital were selected as the coronary heart disease group, 75 patients with coronary heart disease combined with hyperthyroidism as the hyperthyroidism group, and 75 healthy subjects in the same period were selected as the healthy control group. The renin angiotensin system activity [plasma renin(PRA), angiotensin converting enzyme(ACE), angiotensin II(AT II), and left atrial diameter(LAD)] of the subjects in each group were compared, Pearson was used to analyze the correlation between the activity of the renin angiotensin system and thyroid stimulating hormone(TSH), serum free triiodothyronine(FT₃), serum free thyroxine(FT₄), and LAD. Multivariate logistic regression was used to analyze the related influencing factors of atrial fibrillation in patients with coronary heart disease and hyperthyroidism. Results The levels of PRA, ACE, AT Ⅱ, and LAD in patients with hyperthyroidism were higher than those in patients with coronary heart disease and healthy controls(P<0.05); The levels of PRA, ACE, AT Ⅱ, and LAD in patients with atrial fibrillation in the coronary heart disease group and hyperthyroidism group were higher than those without atrial fibrillation(P<0.05). The levels of patients with atrial fibrillation in the hyperthyroidism group were higher than those in the coronary heart disease group(P<0.05). The levels of patients without atrial fibrillation in the hyperthyroidism group were higher than those without atrial fibrillation in the coronary heart disease group(P<0.05), Patients with persistent atrial fibrillation were higher than those with paroxysmal atrial fibrillation(t/P=9.647/<0.001, 2.584/0.012, 13.133/<0.001, 3.559/<0.001). Comparison of serum TSH levels in patients with hyperthyroidism<coronary heart disease<healthy control group(F/P=349.626/<0.001), and comparison of serum FT₃ and FT₄ levels in patients with hyperthyroidism>coronary heart disease>healthy control group(F/P=472.196/<0.001, 506.342/<0.001). Pearson correlation analysis showed that PRA was positively correlated with TSH, while AT Ⅱ and ACE were negatively correlated with TSH(r=0.769,-0.792,-0.803,P<0.001); ACE was positively correlated with FT₃ and FT₄(r=0.718, 0.680,P<0.001); PRA, ACE, AT Ⅱ were positively correlated with LAD(r=0.795, 0.790, 0.751,P<0.001); Logistic regression analysis showed that low TSH, high FT₃, high FT₄, high PRA, high ACE, and high AT Ⅱ were risk factors for atrial fibrillation in patients with coronary heart disease and hyperthyroidism [OR(95%CI)=9.080(1.694 to 48.671), 10.103(1.582 to 64.519), 10.200(1.805 to 57.643), 12.730(1.947 to 83.226), 15.123(3.684 to 62.081), 9.667(1.032 to 90.557)]. Conclusion The levels of PRA, ACE, AT Ⅱ, and LAD in patients with coronary heart disease and hyperthyroidism are abnormally elevated, and are closely related to atrial fibrillation. The activity of the renin angiotensin system is associated with TSH, FT₃,FT₄, and LAD, and are all independent risk factors for atrial fibrillation in patients with coronary heart disease and hyperthyroidism.

Coronary artery disease;                    Hyperthyroidism;                    Atrial fibrillation;                    Renin-angiotensin system;