Endocrine Abstracts

Introduction: Serum thyroid hormone levels have been described in several systemic non-thyroideal illnesses, among them acute heart diseases. The aim of this study was to investigate the relationship between thyroid functions and widespread of ACS, and to evaluate the potential changes in thyroid hormone profile in acute coronary syndromes (ACS) at the time of diagnosis and compare them between two groups, based on therapeutic implications and distinct prognoses: unstable angina/ non-ST-segment elevation acute myocardial infarction (UA/NSTEMI) and ST-segment elevation acute myocardial infarction (STEMI).

Material and method: Ninety-four patients admitted to the coronary care unit of our center were evaluated. Patients were excluded if they were known to have thyroid function test abnormalities. Coronary artery angiogram was performed in all patients. Significant stenosis was defined as the internal diameter decreased by more than 50%. Groups were re-grouped according to the number of significantly stenotic vessels into normal, 1-vessel, 2-vessel, and 3-vessel diseased groups. Thyroid functions were evaluated in groups.

Results: There were 67 patients with UA/NSTEMI (46 men, 21 women, and the mean age 60.3±11.3 years), and 27 patients with STEMI (13 men, 14 women, and the mean age 64.0±13.0 years) included. Thyroid hormone levels (thyroid-stimulating hormone (TSH), free triiodothyronine (fT₃), free thyroxine (fT₄)) were compared in UA/NSTEMI and STEMI groups on admission. There were no significant differences between two groups for fT₃, fT₄ and TSH levels (P>0.05). Also, thyroid functions were not associated with the widespread of coronary artery disease according to coronary angiography (P>0.05).

Conclusion: Thyroid function tests are altered in patients with ACS. The changes are characterized by euthyroid sick syndrome. However, our results show that the thyroid functions are not different between UA/NSTEMI and STEMI groups. Also thyroid functions in acute stage are not seems to be associated with the widespread of coronary artery disease.