Patients with SICM have poor prognosis, and the mechanisms underlying its occurrence are related to toxins, cytokines, nitric oxide, complement activation, apoptosis, and disordered energy metabolism [7-9]. We conducted a prospective cohort study and discovered the relationship between MYO and SICM. When patients' MYO levels are higher than 155.25 ng/ml, it indicates a higher likelihood of SICM occurrence. The combined use of MYO, NT-proBNP, and SOFA is even more effective in predicting SICM.
In the study by Yao et al., elevated MYO levels in sepsis patients were also mentioned. MYO is correlated with disease severity and prognosis [4].In this article, MYO can predict the occurrence of SICM, which illustrates the importance of MYO in sepsis. The presence of systemic inflammatory response and inadequate tissue perfusion can lead to mitochondrial dysfunction and direct damage to neuromuscular tissue [10-12]. After fluid resuscitation, ischemia-reperfusion injury may occur. This complex cascade of damage may induce muscle fiber rupture and cell death. At this point, MYO is released into the bloodstream, leading to increased MYO levels [13].
BNP can reflect the status of cardiac load. When the loading conditions shift towards the unfavorable part of the Frank-Starling curve, the rise in BNP can provide indirect information about cardiac function. BNP levels can reflect the condition of myocardial damage, making NT-proBNP an excellent prognostic indicator [14-16]. Our results are consistent with those of Jeong et al., where elevated NT-proBNP is a risk factor for septic cardiomyopathy [17].
The SOFA score has been confirmed as an independent risk factor for the occurrence of SICM, which is consistent with the research findings of Narváez et al. [18]. In this study, we proposed for the first time a combined predictive model incorporating MYO, NT-proBNP, and SOFA scores to predict the onset of SICM. The SOFA score is a tool for comprehensively assessing the function of multiple organ systems, including the respiratory, hematologic, hepatic, cardiovascular, neurological, and renal systems.This indicates that the predictive model we have developed is capable of more fully reflecting the patient's condition.
We employed a prospective cohort study method and utilized propensity PSM to reduce the impact of confounding factors. This method is particularly important in observational studies because it helps to mitigate data bias and the influence of confounding variables, making the comparison between the experimental and control groups more reasonable. In this way, we revealed for the first time the relationship between MYO and septic cardiomyopathy.
However, our study also has some limitations. As a single-center study, the case source is mainly limited to internal medicine patients, which may limit the generalizability of the results. In addition, we used the change in LEVF to define SICM, but the measurement of LEVF may be affected by loading conditions, especially afterload, and therefore may not be a sensitive indicator of the intrinsic contractility of the myocardium [19-21]. Speckle tracking echocardiography (STE) is an emerging echocardiographic technique that can predict cardiovascular outcomes and provide prognostic data independent of LEVF [22-23]. STE, by tracking speckles in myocardial regions, can more accurately reflect left ventricular function and thus may be a more effective tool for assessing SICM.
In future research, we recommend expanding the sample size and adopting multicenter studies to further validate our findings. Moreover, considering the relationship between MYO levels and the prognosis of septic patients [4]. Future studies could include patient outcomes in their considerations to assess the predictive value of MYO for the prognosis of SICM patients. This may involve using advanced techniques such as STE to more accurately assess myocardial function and exploring other potential biomarkers to improve the accuracy of diagnosis and prognosis assessment of SICM. The Global Longitudinal Strain (GLS), derived from STE, is a powerful indicator of left ventricular contractility. It measures the change in length relative to the diastolic period during systole, providing a comprehensive assessment of the left ventricle's performance. GLS represents the average of the peak longitudinal strain values across all left ventricular segments, making it a sensitive and robust parameter for evaluating left ventricular function and detecting subclinical abnormalities[24-26]. With these methods, we can look forward to making greater progress in the prediction and treatment of septic cardiomyopathy.