Introduction: Myocardial injury after non-cardiac surgery (MINS) is a prevalent complication. It is caused by both cardiac and noncardiac pathophysiological mechanisms. Previous studies have identified pentraxin-3 (PTX-3) and suppression of tumourigenicity 2 (ST2) as potential biomarkers associated with myocardial injury. This study is designed to evaluate the role of PTX-3 and ST2 in Methods: This prospective observational cohort study involved patients who were deemed to be at moderate to high-risk of undergoing non-cardiac surgery. In patients with normal preoperative hs-cTnT levels, MINS was defined as a pattern of increase and/ or decrease, in high-sensitivity cardiac troponin T (hs-cTnT) levels at 24 and 72 hours postoperatively. Patients without a significant change in hs-cTnT levels pre- and postoperatively were considered MINS-negative. Preoperative PTX-3 and ST2 biomarker levels were compared between MINS-positive and MINS-negative groups. Results: The study population comprised 340 patients, of whom 79 (23.24%) were classified as MINS-positive and 261 (76.76%) as MINS-negative. PTX-3 levels were significantly higher in the MINS-positive group than in the MINS-negative group (0.24 +/- 0.11 vs. 0.021 +/- 0.06, p=0.007). There was no significant difference in the level of ST2 between the two groups of patients. Conclusion: Elevated PTX-3 levels in the MINS-positive group suggest that this biomarker may serve as a valuable predictor of myocardial injury.