To explore the diagnostic value of ultrasonocardiography (UCG) combined with serum cardiac troponin I (cTnI) and N-terminal brain natriuretic peptide precursor (NT-proBNP) in myocardial injury after multiple injuries.

A total of 160 patients with multiple injuries who were admitted to the Emergency Department of Wujin People′s Hospital in Changzhou City from May 2023 to August 2025 were enrolled, including 84 cases with myocardial injury and 76 cases without myocardial injury. According to the degree of myocardial injury, they were divided into mild injury (n=39), moderate injury (n=25) and severe injury (n=20). Compared left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), and serum cTnI and NT-proBNP levels between patients with and without myocardial injury, as well as among patients with different degrees of myocardial injury after multiple injuries, the Pearson correlation analysis was used to analyze the correlation between LVEDD, LVESD and LVEF and serum cTnI and NT-proBNP. The diagnostic efficacy of single indicator and combined detection for myocardial injury after multiple injuries was evaluated by receiver operator characteristic (ROC) curve.

The LVEDD, LVESD, cTnI, and NT-proBNP levels in the group with myocardial injury were (52.85±4.12)mm, (41.58±5.23)mm, (1.25±0.26)μg/L, and (1 856.32±185.47)ng/L, respectively, which were higher than those in the group without myocardial injury [(43.25±4.61)mm, (35.12±4.35)mm, (0.04±0.01)μg/L, and (97.56±10.82)ng/L]. The LVEF [(45.23±4.65)%] was lower than that in group without myocardial injury [(55.68±4.21)%] (t=13.910, 8.444, 40.532, 82.517, 14.845, all P<0.01). In patients with multiple injuries, LVEDD and LVESD were positively correlated with cTnI (r=0.472, 0.460), and both were positively correlated with NT-proBNP (r=0.394, 0.401). LVEF was negatively correlated with cTnI and NT-proBNP (r=-0.498, -0.385). The LVEDD, LVESD, cTnI, and NT-proBNP in the severe myocardial injury group after multiple injuries were significantly higher and the LVEF was significantly lower than those in the moderate and mild group. The moderate group also had higher LVEDD, LVESD, cTnI, and NT-proBNP and lower LVEF than those in the mild group (all P<0.05). ROC curve analysis showed that among the single indicator, the diagnostic efficacy of cTnI was the best (AUC=0.830), the AUC of the combined detection indicators was 0.956, respectively greater than those of the individual indicator.

Patients with myocardial injury after multiple injuries exhibit structural and functiond cardiac abnormalities and elevated serum markers, and the trend of indicator changes is consistent with the degree of injury. UCG combined with serum cTnI and NT-proBNP detection can significantly improve the diagnostic efficiency of myocardial injury after multiple injuries.