Incidence and Predictors of Myocardial Injury After Noncardiac Surgery: A Retrospective Cohort Analysis from a Tertiary Center

INTRODUCTION: Myocardial injury after noncardiac surgery (MINS) is a prevalent yet often underdiagnosed perioperative complication, primarily characterized by elevated cardiac troponin levels in the absence of ischemic symptoms. MINS is associated with increased short- and long-term morbidity and mortality, making its detection and prevention clinically important. This study aimed to determine the incidence of MINS and to identify perioperative risk factors contributing to its development, as well as to evaluate its impact on early postoperative mortality.
METHODS: This retrospective cohort study included 418 adult patients who underwent noncardiac surgery between January 2024 and May 2025 at a tertiary care center and were admitted to the postoperative intensive care unit. High-sensitivity troponin I levels were measured at 1, 24, and 48 hours postoperatively. MINS was defined as troponin elevation above 17 ng/L in females and 35 ng/L in males. Demographic data, surgical characteristics, comorbidities, and clinical outcomes were analyzed. Logistic regression was used to identify independent predictors of MINS and mortality.
RESULTS: MINS occurred in 28.5% of patients. Significant associations were found between MINS and male gender (OR=1.61; 95% CI: 1.03–2.53), type of surgery (p=0.034), and surgical urgency, with emergency surgeries showing a paradoxically lower MINS incidence (OR=0.51; 95% CI: 0.33–0.81). The presence of MINS was associated with a significantly higher postoperative mortality rate (18.5% vs. 4%; p<0.001). Independent predictors of mortality included emergency surgery (OR=8.39), prolonged ICU stay (OR=1.12 per day), and lower BMI (p=0.02).
DISCUSSION AND CONCLUSION: MINS is a common and clinically significant condition in the postoperative setting, associated with increased mortality and prolonged ICU stays. Routine troponin monitoring in high-risk surgical patients may facilitate early detection and targeted management. Proactive perioperative strategies are essential to reduce the incidence and impact of MINS.