Application of TTR tetramer in preparation of product for diagnosing ejection fraction retention type heart failure

Abstract

The invention relates to the technical field of medical detection, in particular to application of a TTR tetramer in preparation of a product for diagnosing ejection fraction retention type heart failure. Experiments prove that in heart failure patients, TTR tetramers in HFpEF patients are obviously higher than those in non-HFpEF patients, and it is prompted that the TTR tetramers are related to HFpEF. According to the present invention, the diagnosis model and the kit using the TTR tetramer as the biomarker have good sensitivity and good specificity, can achieve the diagnosis or the auxiliary diagnosis, the treatment guidance and the prognosis of the HFpEF, and can improve the identification of different heart failure types such as the HFpEF and the non-HFpEF.

Description

Technical Field

[0001] The present invention relates to the technical field of medical detection, and particularly relates to the application of TTR tetramer in the preparation of products for diagnosing heart failure with preserved ejection fraction (HFpEF). Background Art

[0002] Heart failure (HF) is a complex clinical syndrome, the severe and terminal stage of all cardiovascular diseases, and also the main cause of death in cardiovascular diseases. According to the different left ventricular ejection fractions (LVEF) and the changes after treatment, it is divided into heart failure with reduced ejection fraction (HFrEF, LVEF < 40%), heart failure with mildly reduced ejection fraction (HFmrEF, LVEF is 40% - 49%), and heart failure with preserved ejection fraction (HFpEF, LVEF ≥ 50%). Among them, the proportion of HFpEF patients is as high as more than 50%. At the same time, the prevalence of HFpEF is between 1% and 3%, and it is expected that with the extension of human life expectancy, the improvement of diagnostic awareness, and the increase in the number of patients with obesity, diabetes, hypertension, and atrial fibrillation, the number of HFpEF patients will further increase, which is one of the main causes threatening human health and increasing the medical burden.

[0003] However, since the ejection fraction of HFpEF patients is normal and the symptoms and signs of heart failure are often non-specific, clinicians have certain difficulties in diagnosing HFpEF, and there is no clear and effective treatment plan and diagnostic criteria. At present, the main assessment methods for suspected HFpEF patients mainly include H 2The FPEF score and the European Society of Cardiology's HFA-PEFF scoring process combine clinical features and parameters to distinguish HFpEF from non-cardiogenic dyspnea. However, patients with a low score cannot be completely excluded from having HFpEF. According to the 2016 definition of the European Society of Cardiology, the diagnosis of HFpEF can be considered from the following four aspects: 1) The presence of symptoms and / or signs of heart failure (which may not be present in patients in the early stage of heart failure or after diuretic treatment); 2) Preserved ejection fraction (LVEF ≥ 50%); 3) Elevated natriuretic peptide levels (BNP ≥ 35 pg / mL and / or NT-proBNP ≥ 125 pg / mL) (BNP or NT-proBNP may be normal in some HFpEF patients); 4) The presence of at least one of the following: (i) Related structural heart disease (left ventricular hypertrophy and / or left atrial enlargement); (ii) Objective evidence of left ventricular diastolic dysfunction. These diagnoses usually require evidence obtained through objective examinations such as imaging (stress echocardiogram) and invasive hemodynamic methods (pulmonary capillary wedge pressure (PCWP) or left ventricular end-diastolic pressure (LVEDP)). However, these diagnostic methods are cumbersome, and their accuracy and specificity may be limited by patient body size and operator experience, easily leading to missed diagnoses and misdiagnoses. Based on this, the present invention aims to discover a non-invasive and specific blood biomarker that helps in the diagnosis, auxiliary diagnosis, treatment guidance, and prognosis judgment of HFpEF, and reduces the mortality rate of HFpEF patients.

[0004] Prealbumin (PAB), also known as transthyretin (TTR), is a serum protein synthesized by hepatocytes and rapidly transported. Its physiological function is mainly to bind and transport thyroid hormones and retinol in plasma and cerebrospinal fluid. It has a molecular weight of approximately 55 kDa and is composed of four identical monomers. Due to gene mutations or aging, the stability of the tetramer decreases, decomposing into dimers and monomers, with a half-life of 1.9 days in plasma. TTR is a negative acute-phase protein and plays an important role in physiological processes such as the body's stress response, clearance of necrotic substances, and tissue repair. In the past, it was mainly used clinically to evaluate inflammatory responses, liver function damage, and malnutrition. In recent years, a large number of studies have revealed a close association between TTR and many cardiovascular diseases, showing unique value in assessing the severity and prognosis of diseases such as heart failure and coronary heart disease, and can be used as a practical and easily obtainable indicator in clinical cardiology work to guide the diagnosis and treatment process. However, there is currently no relevant report on the relationship between the content level of TTR tetramer and HFpEF. Summary of the Invention

[0005] To solve the problems existing in the prior art, the object of the present invention is to provide an application of TTR tetramer in the preparation of a product for diagnosing heart failure with preserved ejection fraction, and the product can achieve the diagnosis or auxiliary diagnosis of HFpEF, which is beneficial to the treatment guidance and prognosis judgment of HFpEF.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In the first aspect, the present invention provides an application of TTR tetramer in the preparation of a product for diagnosing heart failure with preserved ejection fraction.

[0008] In one embodiment, the application includes determining whether a patient has heart failure with preserved ejection fraction by detecting the content level of TTR tetramer in a patient sample.

[0009] In one embodiment, the product includes one or more of reagents, reagent kits, and chips.

[0010] In a preferred embodiment, the usage mode of the product is:

[0011] Taking the content level of TTR tetramer in a patient sample as a variable and substituting it into the HFpEF patient diagnosis model, and the model is:

[0012] Logit(P) = (-8.267) + 2.837 × [content level of TTR tetramer].

[0013] In a more preferred embodiment, the determination criterion of the model is: when Logit(P) ≥ 0.51, it is diagnosed as HFpEF; when Logit(P) < 0.51, it is diagnosed as non-HFpEF.

[0014] In a preferred embodiment, the reagent kit is an ultra-high performance liquid chromatography reagent kit.

[0015] In a preferred embodiment, the sample is patient serum or plasma.

[0016] In a preferred embodiment, the reagent kit further includes calibrators, quality control products, diluents, etc.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] The content level of TTR tetramer in patients with HFpEF is significantly higher than that in patients without HFpEF; at the same time, the diagnostic model established using TTR tetramer has good sensitivity and specificity and high consistency in the validation population; more particularly, without the need for imaging or invasive hemodynamic examinations, therefore, it can be used as a biomarker for the diagnosis and prognostic monitoring of patients with HFpEF, and at the same time provide new ideas for the treatment strategies of patients. Brief Description of the Drawings

[0019] Figure 1 It shows the difference in the content levels of TTR tetramer in the sera of non-heart failure patients, HFpEF patients, and non-HFpEF patients in Example 1;

[0020] Figure 2 It shows the ROC curve analysis of the diagnostic model for HFpEF patients among heart failure patients in Example 2.

[0021] Figure 3 It shows the difference in the content levels of TTR tetramer in the sera of HFpEF patients and non-HFpEF patients in Example 3. Detailed Description of the Invention

[0022] The invention object, technical solution, and beneficial effects of the present invention will be further described in detail below. It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the claimed invention. Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0023] The product for detecting TTR tetramer as a biomarker is a kit in the following examples. The kit contains reagents for detecting TTR tetramer. At the same time, the kit is an ultra-high performance liquid chromatography kit, and the control samples of the kit are from non-heart failure patients and non-HFpEF patients, and the samples are sera or plasmas. Based on the common general knowledge familiar to those skilled in the art, this product can be other products that can achieve the same prediction effect in medicine.

[0024] Example 1: Analysis of the Difference in the Content Levels of TTR Tetramer in the Sera of Non-Heart Failure, Non-HFpEF, and HFpEF Patients

[0025] Experimental Subjects: Serum samples of patients clinically diagnosed with non-heart failure in the Fourth Affiliated Hospital of Harbin Medical University and patients clinically diagnosed with heart failure in the First Affiliated Hospital of Jinzhou Medical University and the First Affiliated Hospital of Dalian Medical University were collected. This study was approved by the ethics committees of each hospital, and all enrolled patients had signed informed consent forms.

[0026] Experimental grouping: 30 non-heart failure patients were enrolled, including 21 males and 9 females, with an average age of 67.0 years. Among all the enrolled heart failure patients, 25 were non-HFpEF and 30 were HFpEF; in the non-HFpEF group, there were 20 males and 5 females, with an average age of 63.8 years; in the HFpEF group, there were 17 males and 13 females, with an average age of 61.8 years.

[0027] Diagnostic criteria for HFpEF:

[0028] (1) Presence of heart failure symptoms and / or signs

[0029] (2) LVEF ≥ 50%, and meeting at least one of the following conditions:

[0030] Elevated natriuretic peptide level a

[0031] Or, E / e' ≥ 15 measured by echocardiogram

[0032] a: Need to meet one of the following situations:

[0033] ① Sinus rhythm: BNP ≥ 35 pg / ml or NT-proBNP ≥ 125 pg / ml;

[0034] ② Atrial fibrillation: BNP ≥ 105 pg / ml or NT-proBNP ≥ 365 pg / ml

[0035] Inclusion criteria:

[0036] (1) Aged 18 years or older;

[0037] (2) Suspected heart failure patients;

[0038] (3) Meeting the relevant diagnostic criteria.

[0039] Exclusion criteria:

[0040] (1) Unstable vital signs, expected survival less than 1 year;

[0041] (2) Taking any drugs that affect myocardial repolarization (quinidine, amiodarone, sotalol, digitalis, etc.) within 2 weeks;

[0042] (3) Patients with cardiac pacemakers or ICD implants;

[0043] (4) Severe valvular heart disease, pericarditis, congenital heart disease;

[0044] (5) Acute myocardial infarction occurred within 2 weeks;

[0045] (6) Heart failure patients secondary to acute coronary syndrome, severe myocarditis or pericarditis, active endocarditis, etc.

[0046] (7) Patients with chronic heart failure caused by other systemic diseases (such as hematological diseases: chronic anemic heart disease, endocrine and metabolic diseases, hyperthyroid cardiomyopathy, etc.);

[0047] (8) Patients with severe diseases in other systems, such as malignant tumors, liver cirrhosis, renal insufficiency, infectious diseases, connective tissue diseases, endocrine diseases, autoimmune diseases, hemorrhagic diseases, multiple organ failure, etc.;

[0048] (9) Those with electrolyte disorders: low potassium, low calcium, low magnesium, etc.;

[0049] (10) Those with unmeasurable QT interval and poor echocardiogram display;

[0050] (11) Pregnant and lactating patients;

[0051] (12) Cognitive and behavioral ability disorders; mental diseases.

[0052] Grouping criteria:

[0053] Non-heart failure group: Suspected heart failure, does not meet the heart failure diagnosis criteria;

[0054] Non-HFpEF group: Meets the heart failure diagnosis, does not meet the HFpEF diagnosis criteria;

[0055] HFpEF group: Meets the heart failure and HFpEF diagnosis criteria.

[0056] Experimental method: Use a TTR tetramer detection kit (ultra-high performance liquid chromatography method) to detect the content level of TTR tetramer in serum samples.

[0057] Experimental results: The results are as Figure 1 shown. It can be seen from the figure that compared with non-heart failure patients, the content level of TTR tetramer in the blood of heart failure patients (including HFpEF patients and non-HFpEF patients) is significantly reduced (p = 0.012, p < 0.001); among heart failure patients, the content level of TTR tetramer in HFpEF patients is significantly higher than that in non-HFpEF patients (p < 0.001), and the differences between groups are statistically significant.

[0058] Example 2: Establishment of a diagnostic model for HFpEF patients

[0059] In order to diagnose or assist in the diagnosis of HFpEF and monitor the treatment effect, a diagnostic model was established. Using SPSS software, binary logistic regression was performed on TTR tetramer, and the content level of TTR tetramer and a constant were included in the final model, and the model equation was determined as:

[0060] Logit(P) = (-8.267) + 2.837 × [TTR tetramer content level].

[0061] The cut-off value for the model diagnosis result to evaluate HFpEF is 0.51. When Logit(P) ≥ 0.51, it is diagnosed as HFpEF; when Logit(P) < 0.51, it is diagnosed as non-HFpEF.

[0062] The sensitivity, specificity, and diagnostic efficacy of the diagnostic model were evaluated using the Receiver Operating Characteristic (ROC) curve. The area under the ROC curve of the established model was 0.927, as Figure 2 shown.

[0063] Example 3: Verification of the HFpEF patient diagnostic model

[0064] Based on the same criteria as the discovery cohort, 30 patients diagnosed with HFpEF and 30 patients diagnosed with non-HFpEF were re-screened at the First Affiliated Hospital of Dalian Medical University as the validation cohort (all enrolled patients had signed informed consent forms). The content level of TTR tetramer in the serum samples was detected using a TTR tetramer detection kit (ultra-high performance liquid chromatography). The content level of TTR tetramer in the validation sample serum was significantly higher in HFpEF patients than in non-HFpEF patients (p < 0.001), as Figure 3 . The diagnostic model established in Example 2 was used to predict HFpEF in the patients of the validation cohort, and the content level of TTR tetramer in the validation sample was substituted for calculation. Patients with the actual status of HFpEF were the "true positive group", and patients with the actual status of non-HFpEF were the "true negative group". Sensitivity is the "true positive rate", which is the probability of correctly diagnosing HFpEF patients; specificity is the "true negative rate", which is the probability of correctly diagnosing non-HFpEF patients. According to the fourfold table calculation (Table 1), the actual predicted sensitivity of this model for the HFpEF validation cohort patients was 93.3%, and the specificity was 96.7%.

[0065] Table 1: Verification of the diagnostic efficacy of the diagnostic model

[0066]

[0067] It should be noted that the above embodiments only describe the technical solutions and technical features of the present application specifically and clearly. For those skilled in the art, the solutions or features that belong to the prior art or common general knowledge are not described in detail in the above embodiments.

[0068] In addition, the technical solution of the present application is not limited to the above embodiments. Those skilled in the art should take the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation manners that can be understood by those skilled in the art.

Claims

1. Use of a TTR tetramer in the preparation of a product for diagnosing heart failure with preserved ejection fraction.

2. The use according to claim 1, characterized in that The application includes determining whether the patient suffers from heart failure with preserved ejection fraction by detecting the level of TTR tetramer in a patient sample.

3. The use according to claim 1, characterized in that The product includes one or more of a reagent, a kit and a chip.

4. The use according to any one of claims 1 to 3, characterized in that: The product is used in the following ways: The content level of TTR tetramer in the patient sample is used as a variable and substituted into the HFpEF patient diagnostic model, the model is: Logit(P)=(-8.267)+2.837×[TTR tetramer content level].

5. The use according to claim 4, characterized in that The judgment criteria of the model are: when Logit (P) ≥ 0.51, it is diagnosed as HFpEF; when Logit (P) < 0.51, it is diagnosed as non-HFpEF.

6. The use according to claim 3, characterized in that The kit is an ultra-high performance liquid chromatography kit.

7. The use according to claim 4, characterized in that The sample is serum or plasma of a patient.

8. The use according to claim 3 or 6, characterized in that: The kit also includes calibrators, quality control products, diluents, etc.

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