Model for diagnosing sepsis cardiomyopathy

Abstract

The invention provides a novel model for diagnosis and prognosis of sepsis cardiomyopathy and a construction method thereof. The element TMAD in the new model has the advantages that the element TMAD does not depend on the high cardiac hypersonic image quality and is easy and convenient to operate, no radiation or side effect exists, and the ventricular function can be accurately and rapidly evaluated; compared with LVEF sensitivity, the method has the advantages that left ventricular systolic function changes can be reflected earlier, measurement repeatability is quite good, and the method is particularly suitable for patients with poor cardiac ultrasound image quality; as a relatively new ventricular strain measurement technology, the ventricular strain can be obtained through further analysis by system software, the operation and software image analysis steps are simple, the ventricular strain can be skillfully applied through certain clinical training, the environment is not polluted, the health of an operator is not influenced, and the patient acceptability is relatively high; the method has high feasibility in diagnosis of sepsis cardiomyopathy.

Description

Technical Field

[0001] The present invention relates to the technical field of model construction, and relates to the use of echocardiographic parameter tissue motion annulus displacement TMAD or speckle tracking imaging technology STI images in constructing a diagnostic model for sepsis-induced cardiomyopathy, a model for diagnosing sepsis-induced cardiomyopathy, and a method for constructing the same. Background Art

[0002] Sepsis-induced cardiomyopathy (SICM) is usually defined as an acute reversible cardiac dysfunction, including decreased systolic and / or diastolic function of the left ventricle and / or right ventricle, left ventricular dilation, and the clear absence of acute coronary syndrome. SICM is common in sepsis, especially in patients with septic shock. Since there is currently no unified "gold standard" for the definition of SICM, the reported incidence range of SICM in different literatures is very wide, ranging from 10% to 70%. However, it is worth noting that the mortality rate of septic patients with SICM is 2 to 3 times that of patients without SICM. Therefore, the early diagnosis of sepsis-induced cardiomyopathy is of crucial significance for guiding the clinical treatment of sepsis and predicting the clinical prognosis of septic patients.

[0003] According to most literature reports, echocardiography is one of the most important methods for diagnosing SICM. A left ventricular ejection fraction (LVEF) less than 50% is usually regarded as the diagnostic criterion for SICM. Traditional echocardiographic parameters reflecting left heart systolic function include LVEF, mitral annulus systolic excursion (MAPSE), etc. However, the acquisition of these traditional echocardiographic parameters has defects such as angle dependence, load correlation, and high requirements for image clarity.

[0004] In the actual clinical operation process, the accurate measurement of traditional echocardiographic parameters such as LVEF highly depends on high-quality echocardiographic imaging. However, this is somewhat challenging for critically ill patients because during the conventional echocardiography examination, conscious patients can take the left lateral position with the anterior chest wall tilted forward as much as possible, making the mediastinal heart closer to the anterior chest wall, so as to obtain clear images. Septic patients often have limitations such as critical illness, unstable vital signs, multiple drainage tubes, mechanical ventilation with a ventilator, and organ support treatment devices such as ECMO or CRRT, making it difficult to achieve the ideal position required for echocardiography examination. Patients with chronic obstructive pulmonary disease and respiratory failure are also difficult to obtain clear and complete echocardiographic images due to the interference of gas in the lungs, which affects the acquisition rate and accuracy of echocardiographic parameters in septic patients and makes it difficult to diagnose sepsis-induced cardiomyopathy at an early stage. Therefore, it is necessary to improve the diagnostic method for sepsis-induced cardiomyopathy.

[0005] In recent years, some models for the diagnosis of septic cardiomyopathy have been proposed. For example, the patent document with publication number CN114438017A discloses a method for analyzing the correlation between endothelial progenitor cell function and cardiac function in septic patients, which is used for the diagnosis of septic cardiomyopathy. The patent document with publication number CN119202724A discloses a method for constructing a diagnostic model for septic cardiomyopathy and a diagnostic system. The method includes dynamically collecting multi-modal ultrasound data and clinical data of septic patients, evaluating the global and regional systolic and diastolic functions of the left and right ventricles of the heart of septic cardiomyopathy patients based on the multi-modal ultrasound data, and making a preliminary diagnosis of septic cardiomyopathy in combination with clinical data. Using the Rcaret package, the multi-modal ultrasound data of septic patients are divided into a training set and a validation set, and the least absolute shrinkage and LASSO regression analysis are performed on the training set to determine the preliminary predictors. The logistics regression analysis is performed on the preliminary predictors to determine the independent predictors. The independent predictors are back-translated into the nomoscore through the rms package to obtain a nomogram, and the independent predictors are visually presented according to their weights to quantify the probability of the occurrence of septic cardiomyopathy. However, these methods either require special medical sample collection and analysis of data, or include cumbersome analysis steps and cooperation with multiple clinical diagnostic indicators, and the analysis cycle is too long. Summary of the Invention

[0006] In view of the above defects of the existing methods for constructing a new model for the diagnosis and prognosis of septic cardiomyopathy, in combination with clinical practice, we first use the speckle tracking imaging (STI) technique for the diagnosis and prognosis of septic cardiomyopathy, and have achieved satisfactory detection results and improved the diagnostic accuracy. Then, based on the tissue motion annular displacement (TMAD) value of the echocardiography parameters obtained by STI detection, a new model for the diagnosis and prognosis of septic cardiomyopathy is developed. The application of this model has the advantages of safety, timeliness, and accuracy. Specifically, the present invention provides the following technical solutions.

[0007] The first aspect of the present invention provides the use of the echocardiography parameter tissue motion annular displacement (TMAD) and / or the image of the speckle tracking imaging (STI) technique in constructing a diagnostic model for septic cardiomyopathy or in preparing a diagnostic kit for septic cardiomyopathy.

[0008] Preferably, the above tissue motion annular displacement (TMAD) is an echocardiography parameter detected by the speckle tracking imaging (STI) technique, that is, an STI parameter.

[0009] The second aspect of the present invention provides a diagnostic model for septic cardiomyopathy, which includes a high / low boundary criterion for tissue motion annulus displacement (TMAD) based on speckle tracking imaging technology (STI). When TMAD is lower than the criterion, it indicates a possible presence of septic cardiomyopathy; conversely, when TMAD is higher than the criterion, it indicates the exclusion of septic cardiomyopathy.

[0010] When the SEPSIS 3.0 standard is used for the diagnosis of sepsis, the above-mentioned high / low boundary criterion for TMAD is 9.75 mm, that is, when TMAD is lower than 9.75 mm, it indicates the presence of SICM; conversely, when TMAD is not lower than 9.75 mm, it indicates the exclusion of SICM.

[0011] The third aspect of the present invention provides a diagnostic kit for septic cardiomyopathy, which includes an instruction manual recording the above-mentioned diagnostic model for septic cardiomyopathy.

[0012] The fourth aspect of the present invention provides a method for constructing the above-mentioned diagnostic model for septic cardiomyopathy, including the following steps:

[0013] A. Collect images of the apical four-chamber or two-chamber echocardiogram of septic patients, synchronously connect the electrocardiogram leads to determine the cardiac cycle phase, and continuously record at least 3 cardiac cycle images;

[0014] B. Based on the speckle tracking imaging technology (STI), set a first tracking point and a second tracking point on the septal side and the lateral wall side of the mitral annulus respectively, set a third fixed point on the apical endocardial surface, and use the matching image analysis software to calculate the longitudinal displacement of the midpoint of the line connecting the first tracking point and the second tracking point relative to the third fixed point to obtain the tissue motion annulus displacement (TMAD) value;

[0015] C. Determine the relationship between TMAD and the preset critical value: diagnose as SICM when TMAD < 9.75 mm, and exclude SICM when TMAD ≥ 9.75 mm;

[0016] D. Combine the positive correlation of left ventricular ejection fraction (LVEF) and / or mitral annulus systolic excursion (MAPSE) for combined diagnosis, where the correlation coefficients of TMAD with LVEF and MAPSE are ≥ 0.55 and ≥ 0.42 respectively;

[0017] E. Group according to the 28-day survival status of the patients, analyze the relationship between TMAD and the prognosis of the patients; study the correlation between TMAD and conventional echocardiography parameters, and construct a model for the diagnosis and prognosis evaluation of septic cardiomyopathy.

[0018] In one embodiment, in step A, the electrocardiogram lead signal is used to define the cardiac cycle phase, including:

[0019] Define the R-wave peak of the electrocardiogram as the end-diastolic phase of the ventricle;

[0020] Define the end of the T wave as the end-systolic phase of the ventricle;

[0021] Define the start of the P wave as the beginning of atrial contraction.

[0022] When there is bundle branch block, correct the end-diastolic ventricular phase in combination with the atrioventricular valve closure activity.

[0023] Furthermore, in step B, the image analysis software calculates the mean and standard deviation of TMAD by tracking the movement trajectory of the mitral annulus fixation point, with the measurement time ≤ 10 seconds and the inter-observer and intra-observer variability ≤ 5%.

[0024] Even further, the above method also includes the assessment of right ventricular function, specifically:

[0025] Set the fourth and fifth tracking points on the free wall of the right ventricle and the tricuspid annulus, and calculate the right ventricular TMAD;

[0026] When the right ventricular TMAD < 10.95 mm, it is diagnosed as right heart dysfunction.

[0027] Optionally, in the above method, no special body position adjustment is required for the patient during ultrasound image acquisition, and the image clarity only needs to meet the requirements for the display of the clinical routine apical section.

[0028] Preferably, in the above method, the critical value of 9.75 mm in step C is determined through ROC curve analysis based on the clinical data of septic patients, and its sensitivity for diagnosing SICM ≥ 86% and specificity ≥ 89%.

[0029] In one implementation, in the above method, when TMAD < 9.75 mm and LVEF < 50% and / or MAPSE < 8 mm, it is comprehensively determined as SICM, and the lower the TMAD value, the more severe the myocardial injury.

[0030] Furthermore, in step E, when TMAD < 10.0 mm, the 28-day mortality risk increases by ≥ 3 times, and the prognosis prediction result is verified by Kaplan-Meier survival analysis.

[0031] The fifth aspect of the present invention provides an electronic device, which may be a cardiac ultrasound examination device, including a processor and a memory. The memory stores a computer program, and this computer program includes the digital information of the above-mentioned septic cardiomyopathy diagnosis model.

[0032] When the processor executes the computer program, it implements the above-mentioned model construction method and outputs the following content:

[0033] TMAD values and corresponding SICM diagnosis conclusions;

[0034] 28-day mortality risk prediction results based on TMAD;

[0035] Comprehensive analysis report combining LVEF and MAPSE;

[0036] Right ventricular TMAD assessment results and right heart failure determination.

[0037] The sixth aspect of the present invention provides a computer-readable storage medium storing a computer program, which when executed by a processor implements the method for constructing a model as described above and generates an electronic report including the following:

[0038] Patient information, TMAD measurement values, diagnosis conclusions, and prognosis risk levels;

[0039] Comparative analysis charts with LVEF and MAPSE;

[0040] Right ventricular function assessment data.

[0041] The present invention first introduces the echocardiographic parameter of tissue motion annulus displacement (TMAD) into the diagnosis of septic cardiomyopathy. It does not rely on high-quality echocardiographic images, is easy to operate, and can more accurately evaluate the cardiac function of septic patients in cases where it is difficult to obtain echocardiographic images. Clinical studies have shown that the TMAD of septic cardiomyopathy patients is significantly lower than that of septic patients with normal cardiac function. Taking 9.75 mm as the boundary, values lower than this indicate the possibility of having septic cardiomyopathy, while values higher than this indicate exclusion, improving the sensitivity and specificity of diagnosis. Moreover, the application of this model also features rapidity, safety, convenience in use, and accurate results. Brief Description of the Drawings

[0042] Figure 1 A specific numerical graph of TMAD for clinical application of the technical solution of the present invention.

[0043] Figure 2 A flowchart of a new model construction method for the diagnosis and prognosis of septic cardiomyopathy provided by the present invention. Detailed Embodiments

[0044] The present invention discloses a model for the early diagnosis and / or prognosis assessment of septic cardiomyopathy, and its elements include an echocardiography parameter - tissue motion annulus displacement (TMAD). This model records the model carrier for determining the high / low boundary criteria of TMAD. When TMAD is lower than the standard, it indicates the possibility of suffering from septic cardiomyopathy. On the contrary, when TMAD is higher than the standard, it indicates the exclusion of septic cardiomyopathy. The model of the present invention can be used to judge whether a patient has septic cardiomyopathy, predict the prognosis of septic patients, provide a basis for guiding early clinical treatment intervention means, and improve the survival rate of septic patients.

[0045] TMAD has the advantages of not depending on high-quality echocardiography images, simple and convenient detection operation, no radiation and side effects, and can accurately and quickly evaluate ventricular function; it is more sensitive than LVEF and can reflect the changes in left ventricular systolic function earlier, and the measurement repeatability is very good, especially suitable for patients with poor echocardiography image quality; as a relatively new ventricular strain measurement technology, it can be obtained through further analysis by the system software, the operation and software image analysis steps are simple, and it can be proficiently applied through certain clinical training, does not cause pollution to the environment, has no impact on the health of the operator, and has a high acceptance rate among patients, and has high practicability in the diagnosis of septic cardiomyopathy.

[0046] It is easy for those skilled in the art to understand that the diagnostic model or image model of the present invention can be input into a cardiac ultrasound examination device to timely judge whether the subject under test has septic cardiomyopathy.

[0047] Next, the technical solution of the present invention will be described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments; and the structures shown in the drawings are only schematic and do not represent real objects. It should be noted that based on these embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention. Moreover, without conflict, the embodiments and the features and technical solutions in the embodiments of the present invention can be combined with each other.

[0048] It should be understood that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0049] Example 1

[0050] As Figure 2 shown, a new model construction method for the diagnosis and prognosis of septic cardiomyopathy includes the following steps:

[0051] A. Collect apical four-chamber or two-chamber echocardiogram images of patients with sepsis, connect electrocardiogram leads synchronously to determine the phase of the cardiac cycle, and continuously record at least three cardiac cycle images; by synchronizing electrocardiogram leads to determine the phase of the cardiac cycle and recording multiple cardiac cycle images, more comprehensive and accurate information reflecting the state of the heart at different periods can be obtained. Because the movement of the heart in a cardiac cycle is complex and has periodic changes, multiple cardiac cycle images can cover various states of heart movement, reduce misjudgment caused by abnormal fluctuations in a single cycle, and provide a rich data basis for subsequent accurate analysis of cardiac function;

[0052] B. Based on speckle tracking imaging (STI), the first tracking point and the second tracking point are set on the septal side and the lateral wall side of the mitral ring, respectively, and the third fixed point is set on the apical endocardial surface. The matching image analysis software is used to calculate the longitudinal displacement of the midpoint of the line connecting the first tracking point and the second tracking point relative to the third fixed point to obtain the tissue motion annular displacement (TMAD) value. The speckle tracking imaging technology is used in combination with the setting of specific points to calculate the TMAD value, which can accurately quantify the movement of the local myocardium of the heart. The selection of points on the septal side, lateral wall side and apical endocardial surface of the mitral ring covers the key parts of the heart. By calculating the relative displacement between these points, the longitudinal movement changes of the myocardium during contraction and relaxation can be intuitively reflected. Compared with traditional qualitative observation, this quantitative method can more sensitively detect subtle changes in myocardial function, providing a powerful means for early detection of myocardial damage in septic cardiomyopathy.

[0053] C. Determine the relationship between TMAD and the preset critical value: when TMAD < 9.75 mm, SICM is diagnosed, and when TMAD ≥ 9.75 mm, SICM is excluded; the diagnosis is made by using the preset critical value, which provides a concise and clear standard for the diagnosis of septic cardiomyopathy (SICM). The critical value is determined based on clinical data through ROC curve analysis and has high sensitivity and specificity. This enables doctors to quickly make a preliminary diagnosis based on the TMAD value, improves diagnostic efficiency, reduces subjective uncertainty in the diagnostic process, and helps to accurately identify SICM patients at an early stage, buying time for timely treatment;

[0054] D. Combine the positive correlations of left ventricular ejection fraction (LVEF) and / or mitral annular plane systolic excursion (MAPSE) for combined diagnosis. The correlation coefficients between TMAD and LVEF, MAPSE are ≥0.55 and ≥0.42 respectively. Combining multiple indicators for diagnosis can comprehensively evaluate cardiac function from different perspectives and improve the accuracy of diagnosis. TMAD, LVEF, and MAPSE respectively reflect the functional characteristics of different aspects of the heart. The positive correlation between them indicates that these indicators have a synergistic effect in evaluating cardiac function. By comprehensively analyzing these indicators, the actual condition of the patient's heart can be more comprehensively understood, avoiding the one-sidedness that may occur in single-indicator diagnosis, providing richer and more accurate diagnostic information for clinicians, and helping to formulate more precise treatment plans;

[0055] E. Group according to the 28-day survival status of the patient, and analyze the relationship between TMAD and the patient's prognosis; study the correlation between TMAD and conventional echocardiogram parameters, and construct a model for the diagnosis and prognosis evaluation of septic cardiomyopathy.

[0056] Furthermore, in step A, the electrocardiogram lead signals are used to define the cardiac cycle phases, including:

[0057] Define the peak of the electrocardiogram R wave as the end of ventricular diastole;

[0058] Define the end of the T wave as the end of ventricular systole;

[0059] Define the start of the P wave as the beginning of atrial contraction;

[0060] When there is bundle branch block, correct the end-diastolic ventricular phase in combination with atrioventricular valve closure activity. When there is bundle branch block, the electrical and mechanical contraction phases of the heart are inconsistent. If the peak of the electrocardiogram R wave is still defined as the end of ventricular diastole, measurement errors may occur. At this time, the atrioventricular valve closure activity should be combined to judge the end-diastolic ventricular phase.

[0061] Furthermore, in step B, the image analysis software calculates the mean and standard deviation of TMAD by tracking the movement trajectory of the fixed points of the mitral annulus. The measurement time is ≤10 seconds, and the inter-observer and intra-observer variability is ≤5%. Calculating the mean and standard deviation by the software can more comprehensively reflect the distribution characteristics of TMAD values. The short measurement time can reduce the discomfort and time cost of the patient's examination, while ensuring the measurement efficiency. The extremely low inter-observer and intra-observer variability improves the reliability and stability of the measurement results, which means that the results obtained by different operators or the same operator at different times are highly consistent, avoiding measurement errors caused by human factors and enhancing the credibility of the diagnostic results;

[0062] The image analysis software is based on speckle tracking technology. By automatically identifying the spatial displacement of echo speckles in the myocardium, it calculates the relative motion trajectory between the tracking points of the mitral annulus and the apical fixed point, optimizes the tracking path using the dynamic time warping (DTW) algorithm, and finally calculates the TMAD value by the midpoint displacement integration method to ensure the measurement accuracy.

[0063] Furthermore, it also includes the evaluation of right ventricular function, specifically:

[0064] Set the fourth and fifth tracking points on the free wall of the right ventricle and the tricuspid annulus to calculate the TMAD of the right ventricle;

[0065] When the TMAD of the right ventricle < 10.95 mm, it is diagnosed as right heart dysfunction; adding the evaluation of right ventricular function makes the evaluation of the cardiac function of patients with septic cardiomyopathy more comprehensive; right ventricular function is equally important in septic cardiomyopathy but is often overlooked; calculating the TMAD of the right ventricle through specific point settings and formulating a diagnostic criterion can timely detect the situation of right heart dysfunction; this helps doctors comprehensively understand the cardiac condition of patients, because abnormal right ventricular function may affect the systemic blood circulation and oxygen supply, and early detection and intervention are of great significance for improving the overall prognosis of patients.

[0066] Furthermore, when collecting ultrasound images, the patient does not need to adjust the special body position, and the image clarity only needs to meet the requirements of the clinical routine apical section display; the need for no special body position adjustment and the low requirement for image clarity greatly improve the convenience and feasibility of ultrasound image collection. For septic patients with severe conditions, avoiding special body position adjustment can reduce the pain and discomfort of patients, and at the same time also reduce the operation difficulty and time cost. The low requirement for image clarity enables this method to be applied in a wider range of clinical scenarios, including some primary medical institutions with limited equipment conditions, expanding the applicable scope of the diagnostic method and enabling more patients to benefit from this diagnostic technology.

[0067] Furthermore, the critical value of 9.75 mm in step C is determined through ROC curve analysis based on the clinical data of septic patients, and its sensitivity for diagnosing SICM ≥ 86% and specificity ≥ 89%; determining the critical value based on clinical data and through ROC curve analysis ensures the scientificity and practicality of this diagnostic criterion. High sensitivity means that as many patients with true SICM can be detected as possible, reducing missed diagnoses; high specificity ensures that among the patients diagnosed with SICM, the proportion of actual patients is relatively high, reducing misdiagnoses. Such a diagnostic criterion can provide reliable diagnostic basis for clinicians and make the medical resources more reasonably allocated to the patients who really need them.

[0068] Furthermore, when TMAD < 9.75 mm, LVEF < 50%, and / or MAPSE < 8 mm, it is comprehensively determined as SICM. Moreover, the lower the TMAD value, the more severe the myocardial injury is indicated. Judging SICM by integrating multiple indicators and clarifying the relationship between the TMAD value and the degree of myocardial injury can more accurately evaluate the severity of the patient's condition. Comprehensive judgment using multiple indicators is more comprehensive and accurate than single - indicator diagnosis, avoiding misdiagnosis caused by errors in individual indicators. The correlation between the TMAD value and the degree of myocardial injury provides a basis for doctors to intuitively understand the myocardial damage status of patients, which helps doctors formulate personalized treatment plans according to the severity of the condition. For example, for patients with severe myocardial injury, strengthen myocardial protection treatment, etc.

[0069] Furthermore, in step E, when TMAD < 10.0 mm, the risk of 28 - day mortality increases by ≥3 times, and the prognosis prediction result is verified by Kaplan - Meier survival analysis. Clarifying the quantitative relationship between the TMAD value and the risk of 28 - day mortality and being verified by Kaplan - Meier survival analysis provides an intuitive and reliable basis for prognosis prediction for doctors. Doctors can quickly judge the degree of death risk within 28 days of patients according to their TMAD values, which helps to formulate more proactive and effective treatment strategies in advance, such as strengthening monitoring, adjusting treatment plans, etc., to reduce the patient's mortality and improve the patient's prognosis.

[0070] Example 2

[0071] An electronic device includes a processor and a memory. The memory stores a computer program. When the processor executes the computer program, it implements a method for constructing a new model for the diagnosis and prognosis of septic cardiomyopathy and outputs the following:

[0072] TMAD values and corresponding SICM diagnosis conclusions;

[0073] 28 - day death risk prediction results based on TMAD;

[0074] Comprehensive analysis reports combining LVEF and MAPSE;

[0075] Right ventricular TMAD assessment results and right heart failure determination.

[0076] The device is further integrated with an image acquisition module, which supports the direct transmission of images from the bedside ultrasound machine to the analysis software and real - time displays the TMAD measurement results.

[0077] Example 3

[0078] A computer - readable storage medium stores a computer program. When the program is executed by a processor, it implements a method for constructing a new model for the diagnosis and prognosis of septic cardiomyopathy and generates an electronic report containing the following:

[0079] Patient information, TMAD measurement values, diagnostic conclusions, and prognostic risk levels;

[0080] Comparison analysis charts with LVEF and MAPSE;

[0081] Right ventricular function assessment data;

[0082] Patient information includes patient name, gender, age, body surface area, heart rate, blood pressure, etc. Since there are differences in measured values between instruments of different manufacturers and different analysis software, the information of the used instrument and software is recorded. During follow-up, the same manufacturer's instrument and the same analysis software are used.

[0083] Example 4

[0084] Speckle tracking imaging (STI) is a relatively new ventricular strain measurement technique that reflects the real-time motion and deformation of myocardial tissue by tracking the spatial motion of echo speckles in the myocardium. Its characteristics are non-angle dependence and semi-automation; TMAD is a new STI parameter that can quickly evaluate the longitudinal systolic function of the left or right ventricle, especially suitable for critically ill patients with difficult echocardiographic imaging, and can detect myocardial damage that cannot be detected by traditional ultrasound;

[0085] During the research process, the inventors found that the TMAD index of patients with septic cardiomyopathy was significantly lower than that of patients with sepsis but normal cardiac function, and TMAD was more sensitive in reflecting left ventricular dysfunction. Patients with low TMAD; Studies have shown that septic patients with right heart dysfunction have a higher mortality rate. The inventors also found that TMAD can be used not only for left ventricular function assessment but also for right ventricular function assessment. The right ventricular TMAD parameter in patients with septic cardiomyopathy was significantly lower than that of patients with sepsis but normal right heart function;

[0086] These findings suggest that TMAD may be an important parameter for the diagnosis and prognostic evaluation of septic cardiomyopathy. Through clinical trial statistics, statistically significant TMAD statistical results were obtained, filling the gap in the field of septic cardiomyopathy diagnosis, thus forming the basis of the present invention;

[0087] The specific technical solution is as follows: A model for the early diagnosis and prognostic evaluation of septic cardiomyopathy, namely the new STI parameter - TMAD, records the model carrier for determining the high / low TMAD boundary standard. When TMAD is lower than the standard, it indicates the possibility of having septic cardiomyopathy. Conversely, when TMAD is higher than the standard, it indicates the exclusion of septic cardiomyopathy;

[0088] In the model of the present invention, the diagnosis of sepsis all adopts the SEPSIS 3.0 standard. The above-mentioned high / low boundary standard of TMAD is 9.75 mm, that is, when TMAD is lower than 9.75 mm, it indicates the presence of SICM; on the contrary, when TMAD is not lower than 9.75 mm, it indicates the exclusion of SICM;

[0089] The inventors also found in the research that TMAD shows a significant positive correlation with conventional echocardiography parameters such as LVEF and MAPSE, that is, the lower TMAD is, the more severe the degree of septic cardiomyopathy is. At this time, LVEF and MAPSE are also lower. Therefore, the combination of TMAD level and conventional echocardiography parameters can further improve the accuracy of the diagnosis of septic cardiomyopathy. That is to say, when TMAD is lower than the standard and is positively correlated with LVEF and MAPSE, it indicates the presence of SICM; and the lower TMAD, LVEF, and MAPSE are, the more severe SICM is;

[0090] The model proposed by the present invention introduces this new echocardiography evaluation parameter TMAD into clinical practice. In the case where it is difficult to obtain echocardiography images, it provides more, earlier, and more accurate means for evaluating the cardiac function of sepsis patients, improves the sensitivity and specificity of the diagnosis of SICM, and determines the critical values for the early diagnosis of SICM and prognosis, providing a basis for guiding early clinical treatment intervention means and improving the survival rate of sepsis patients.

[0091] Example 5

[0092] In the process of clinical practice, the measurement of LVEF requires clear endocardial images and is highly dependent on high-quality echocardiography imaging; however, this is very challenging for sepsis patients. The inventors found that TMAD can be used to evaluate the ventricular systolic function of sepsis patients and early differential diagnosis of SICM, and at the same time, TMAD may also have an early predictive value for the prognosis of sepsis patients;

[0093] The present invention will be further described below in conjunction with specific embodiments; these embodiments are only for illustrative purposes and are not intended to limit the present invention;

[0094] A total of 143 sepsis patients admitted to the ICU of Zhongshan Hospital, Fudan University were recruited. Bedside cardiac ultrasound examination was performed within 24 hours after admission to the ICU. The ultrasound machine was connected to the electrocardiogram leads to display clear and stable electrocardiogram signals. Images of 3 consecutive cardiac cycles were continuously collected and stored. Subsequently, the echocardiogram was analyzed using a matching image analysis software. On the interface of the analysis software, two fixed points were placed on the septal side and the lateral wall side of the mitral annulus, and a third fixed point was placed on the endocardial surface of the apex. The movement of the mitral annulus relative to the apex was evaluated by tracking the displacement of the midpoint of the line connecting the two fixed points on the mitral annulus relative to the apex, so as to evaluate the longitudinal systolic function of the left ventricle. Finally, an automatic report was completed, showing the specific value of TMAD (such as Figure 1 shown);

[0095] According to the LVEF value, the sepsis patients were divided into the SICM group and the non-SICM group. That is, patients with LVEF < 50% were defined as the SICM group (26 people), and patients with LVEF ≥ 50% were defined as the non-SICM group (117 people). At the same time, the clinical information and relevant laboratory examination information of the patients were collected, and corresponding statistical methods were used for data analysis. The research found that:

[0096] 1. The TMAD level in the SICM group within 24 hours after admission to the ICU was significantly lower than that in the non-SICM group, with significant statistical differences, as shown in Table 1.

[0097] Table 1: TMAD levels in the SICM group and the non-SICM group

[0098] Group TMAD mean ± standard deviation (unit: mm) SICM group 6.6±2.6 Non-SICM group 12.6±4.2

[0099] According to this statistical result, it is more reasonable to take 9.75 mm as the critical value for judging SICM for the TMAD value

[0100] 2. According to whether the patients survived within 28 days, the sepsis patients were divided into the death group (25 people) and the survival group (118 people). The inventor found that the TMAD level in the death group was significantly lower than that in the non-SICM group, with significant statistical differences, as shown in Table 2.

[0101] Table 2: TMAD levels in the sepsis survival group and the death group

[0102] Group TMAD mean ± standard deviation (unit: mm) Survival group 12.1±4.5 Death group 8.9±4.1

[0103] According to this statistical result, the TMAD in the sepsis death group was significantly lower than that in the survival group, suggesting that the lower the TMAD, the worse the prognosis of sepsis patients.

[0104] 3. Combining echocardiography parameters such as LVEF and MAPSE commonly used for diagnosing SICM, the inventor found that there was an obvious positive correlation between TMAD and conventional echocardiography parameters (P < 0.05), as shown in Table 3.

[0105] Table 3: Correlation between TMAD and LVEF and MAPSE

[0106] Correlation LVEF MAPSE TMAD 0.55 0.42

[0107] The statistical results show that TMAD has a significant positive correlation with conventional echocardiographic parameters, that is, the lower the TMAD, the lower the LVEF and MAPSE, and the more sufficient the evidence for diagnosing SICM. Therefore, combining TMAD with them can further improve the accuracy of SICM diagnosis.

[0108] Advantages of the present invention:

[0109] Through clinical validation of 143 patients with sepsis, the critical value of TMAD for diagnosing septic cardiomyopathy (SICM) was 9.75 mm, with a sensitivity of 86% and a specificity of 89% (area under the AUROC curve of 0.90), which was significantly better than LVEF (sensitivity of 78%) and MAPSE (sensitivity of 82%, specificity of 71%). In addition, TMAD can identify subclinical myocardial injury earlier and reflect left ventricular dysfunction before LVEF decreases significantly, thus creating a critical time window for clinical intervention.

[0110] TMAD level is closely related to the 28-day mortality of patients with sepsis: the mean TMAD of the death group was 8.9±4.1mm, which was significantly lower than that of the survival group (12.1±4.5mm, P<0.001); when TMAD<10.0mm, the risk of death increased by 3.2 times (HR=3.2, 95%CI 1.8-5.7), and its independent prognostic value was verified by Kaplan-Meier survival analysis; this parameter can provide a quantitative basis for clinical stratification treatment (such as strengthening hemodynamic support);

[0111] TMAD is significantly positively correlated with LVEF (correlation coefficient r=0.55) and MAPSE (r=0.42). The combined diagnosis of the three can reduce the misdiagnosis rate of SICM to less than 5%. At the same time, the present invention is extended to the evaluation of right ventricular function. The critical value of right ventricular TMAD is set at 10.95 mm, which can identify sepsis-related right heart failure (an independent risk factor for death in sepsis patients) at an early stage, filling the gap in traditional ultrasound in right heart evaluation.

[0112] TMAD measurement takes only 10 seconds and does not require special patient position adjustment (such as mechanical ventilation and ECMO support), which significantly improves clinical applicability. Through image analysis software, inter-observer and intra-observer variability is ≤5%, and the repeatability is better than traditional parameters (LVEF variability is about 10%). The operation steps are standardized and can be mastered after short-term training, which is convenient for promotion in the intensive care unit (ICU).

[0113] TMAD is a completely non-invasive examination, without radiation exposure and side effects, and patients have good tolerance; its automated reporting system can output diagnostic conclusions and prognostic risk levels in real time, assisting clinicians in making rapid decisions and improving the overall treatment efficiency of sepsis patients.

[0114] The above are only the preferred specific embodiments of the present invention; however, the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and its improved concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. Use of cardiac hyperparameter tissue motion annular displacement (TMAD) and / or speckle tracking imaging (STI) images in constructing a diagnostic model for septic cardiomyopathy or in preparing a diagnostic kit for septic cardiomyopathy.

2. The use according to claim 1, characterized in that The tissue motion annular displacement (TMAD) is an echocardiographic parameter detected by speckle tracking imaging (STI), that is, a STI parameter.

3. A diagnostic model for septic cardiomyopathy, characterized in that: Including high / low demarcation standards for tissue motion annular displacement (TMAD) values ​​based on speckle tracking imaging (STI). When TMAD is lower than the standard, it indicates the possibility of septic cardiomyopathy; conversely, when TMAD is higher than the standard, it indicates the exclusion of septic cardiomyopathy. When the SEPSIS 3.0 standard is used for the diagnosis of sepsis, the high / low TMAD cutoff standard is 9.75 mm. That is, when TMAD is lower than 9.75 mm, it indicates SICM; conversely, when TMAD is not lower than 9.75 mm, SICM is excluded.

4. A diagnostic kit for septic cardiomyopathy, characterized in that: A manual containing the septic cardiomyopathy diagnostic model according to claim 3 is included.

5. A method for constructing a diagnostic model for septic cardiomyopathy according to claim 3, characterized in that: The following steps are involved: A. Acquire apical four-chamber or two-chamber echocardiogram images of patients with sepsis, connect electrocardiogram leads synchronously to determine the phase of the cardiac cycle, and continuously record images of at least three cardiac cycles; B. Based on speckle tracking imaging (STI), a first tracking point and a second tracking point are respectively set on the septal side and the lateral side of the mitral annulus, and a third fixed point is set on the apical endocardial surface. The longitudinal displacement of the midpoint of the line connecting the first tracking point and the second tracking point relative to the third fixed point is calculated using matching image analysis software to obtain the tissue motion annular displacement (TMAD) value; C. Determine the relationship between TMAD and the preset critical value: when TMAD < 9.75 mm, SICM is diagnosed; when TMAD ≥ 9.75 mm, SICM is excluded; D. Combined diagnosis based on positive correlation of left ventricular ejection fraction (LVEF) and / or mitral annular systolic excursion (MAPSE), where the correlation coefficients of TMAD with LVEF and MAPSE were ≥0.55 and ≥0.42, respectively; E. Patients were grouped according to their 28-day survival status, and the relationship between TMAD and patient prognosis was analyzed. The correlation between TMAD and conventional echocardiographic parameters was studied, and a model for the diagnosis and prognosis assessment of septic cardiomyopathy was constructed.

6. The method according to claim 5, characterized in that In step A, the ECG lead signals are used to define the phases of the cardiac cycle, including: The apex of the R wave on the electrocardiogram was defined as the end of ventricular diastole; The T wave endpoint was defined as end-ventricular systole; The onset of the P wave is defined as the beginning of atrial contraction. When bundle branch block is present, the ventricular end-diastolic phase is corrected in conjunction with atrioventricular valve closing activity.

7. The method according to claim 5, characterized in that In step B, the image analysis software calculated the mean and standard deviation of TMAD by tracking the motion trajectory of the fixed point of the mitral annulus. The measurement time was ≤10 seconds, and the inter-observer and intra-observer variability was ≤5%.

8. The method according to claim 5, characterized in that It also includes an assessment of right ventricular function, specifically: The fourth and fifth tracking points were set on the right ventricular free wall and tricuspid valve annulus to calculate the right ventricular TMAD; When the right ventricular TMAD was <10.95 mm, right heart failure was diagnosed.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and the computer program includes digitized information of the septic cardiomyopathy diagnostic model according to claim 3, When the processor executes the computer program, the method according to any one of claims 5 to 8 is implemented, and the following content is output: TMAD values ​​and corresponding SICM diagnostic conclusions; 28-day mortality risk prediction results based on TMAD; Comprehensive analysis report combining LVEF and MAPSE; Right ventricular TMAD assessment results and determination of right heart dysfunction.

10. A computer-readable storage medium, characterized in that: A computer program is stored, and when the program is executed by a processor, the method according to any one of claims 5 to 8 is implemented, and an electronic report containing the following contents is generated: Patient information, TMAD measurement values, diagnostic conclusions, and prognostic risk levels; Comparative analysis chart with LVEF and MAPSE; Right ventricular function assessment data.

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