January 2026, Volume 4, Issue 1

Author

Sreena Sreedhar, Satarla Narendra, Pulkit Jindal, Deepak Sha K, Nithin C and Navpreet Kaur Batth

Abstract

Background: Non-thyroidal illness (NTI), also termed sick euthyroid syndrome (SES), represents transient alterations in thyroid hormone levels that occur during acute or critical illness. Typically, serum thyroid-stimulating hormone (TSH) remains within the normal range, while triiodothyronine (T3), thyroxine (T4), and reverse T3 (rT3) show characteristic fluctuations. Thyroid hormones play a crucial role in maintaining myocardial contractility, hence affecting cardiac function and overall prognosis of the patient. Aim: To estimate prevalence of sick euthyroid syndrome in patients admitted with acute heart failure and to assess its prognostic significance. Discussion: Morbidity of heart failure was assessed as a need for prolonged hospital stay and re-hospitalization as previous literature review showed that it was increased among low T3 subjects. However, such an association was not seen in our study. Conclusion: The prevalence of Sick euthyroid syndrome was found to be 22.3%. The mortality rate as well as re-hospitalization rate among our study subjects was very low, however statistical data showed a slightly more prolonged hospital stay among sick euthyroid subjects. Thyroid function assessment and its treatment whenever indicated is of paramount importance especially among heart failure subjects.