Beyond the initial impact: troponin patterns frequently reveal delayed cardiac injury in polytrauma patients

Abstract Background Cardiac troponin serves as a biomarker for diagnosing myocardial contusion following blunt chest trauma and for differentiating between types of myocardial infarction. However, its interpretation in polytrauma remains challenging due to overlapping pathophysiological mechanisms. This study aims to improve troponin-based cardiac risk stratification to more accurately identify high-risk patients and enhance prognostic assessment. Methods This prospectively performed study included polytraumatized patients (ISS ≥ 16) admitted to a German Level 1 trauma center between January 2024 and July 2025. For each patient, six blood samples collected over ten days were analyzed for Troponin T (TnT) and NT-proBNP; and two transthoracic echocardiograms (24 h and 48 h) and ECGs were evaluated by a cardiologist. Data were correlated with clinical records, trauma-dependent and -independent cardiac risk factors, including the cardiovascular risk score (SCORE2). Results Seventy-seven patients were included (mean age 52 years; 73% male; mean ISS 29). TnT was elevated in 44% at admission and in 73% after 24 h. 13% of the patients were diagnosed with a cardiac contusion. TnT elevation was associated with age ≥ 40 years, higher SCORE2, thoracic injuries, ISS ≥ 25, preclinical arrhythmias, catecholamine therapy, and surgery at admission. Two distinct TnT patterns were found: Group 1 (44%)—elevation already at admission, mirrored the overall risk profile but showed more persistent elevation in patients ≥ 60 years, with very high SCORE2 or catecholamine therapy and was especially linked to sternal fractures. Group 2 (26%)—delayed TnT rise after 24 h, associated with thoracic trauma, ISS ≥ 25, surgery and catecholamine therapy. Complications, including new-onset arrhythmias and higher mortality, occurred in both groups. Conclusion Cardiac involvement in polytrauma is multifactorial and often underrecognized. TnT elevation was associated with higher age, high SCORE2, severe injury, thoracic trauma, arrhythmias, and resuscitation, with a distinct subgroup showing delayed elevation after 24 h. This delayed phenotype is clinically relevant, as most of these patients had thoracic trauma and underwent early surgery, aligning with recommendations for perioperative screening for myocardial infarction. Our findings emphasize routine peri-traumatic and peri-operative troponin measurement and highlight the value of TTE and continuous ECG for detecting evolving cardiac dysfunction. Systematic follow-up is needed to assess long-term outcomes and refine cardiac risk stratification in this vulnerable population.