Evaluation of Thyroid Profile as a Predictor of Poor Prognosis in Acute Coronary Syndrome Patients – A Study of 120 Cases

Open Access

Abstract

Background: Thyroid hormones have significant cardiovascular effects, and alterations in thyroid function are frequently observed in critically ill patients, including those with acute coronary syndrome (ACS). Low triiodothyronine (T3) syndrome and subclinical thyroid dysfunction have been associated with adverse cardiovascular outcomes. This study aimed to evaluate the role of thyroid profile as a predictor of poor prognosis in patients presenting with ACS. Objectives: To assess the prevalence of thyroid function abnormalities in ACS patients and determine their association with short-term in‑hospital outcomes. Methods & Materials: This prospective observational study included 120 consecutive patients diagnosed with ACS. Thyroid profile (TSH, free T3, free T4) was measured within 24 hours of admission. Patients were followed during hospital stay for major adverse cardiac events (MACE) including mortality, cardiogenic shock, heart failure, arrhythmias, and recurrent ischemia. Statistical analysis was performed to assess associations between thyroid abnormalities and outcomes. Results: Thyroid dysfunction was detected in 46.7% of patients, with low T3 syndrome being the most common abnormality (31.7%). Patients with abnormal thyroid profiles had significantly higher rates of in‑hospital MACE (p < 0.05), including mortality and heart failure. Low T3 levels were independently associated with poor prognosis. Conclusion: Abnormal thyroid profile, particularly low T3 syndrome, is common in ACS patients and is associated with worse in‑hospital outcomes. Thyroid hormone assessment may serve as a useful prognostic marker in ACS.